PEMBENTUKAN BUMI DAN PROSES-PROSES GEOMORFOLOGI

GEOMORFOLOGI
Geomorfologi adalah sebuah studi ilmiah terhadap permukaan Bumi dan poses yang terjadi terhadapnya. Secara luas, berhubungan dengan landform (bentuk lahan) tererosi dari batuan yang keras, namun bentuk konstruksinya dibentuk oleh runtuhan batuan, dan terkadang oleh perolaku organisme di tempat mereka hidup. “Surface” (permukaan) jangan diartikan secara sempit; harus termasuk juga bagian kulit bumi yang paling jauh. Kenampakan subsurface terutama di daerah batugamping sangat penting dimana sistem gua terbentuk dan merupakan bagian yang integral dari geomorfologi.
Pengaruh dari erosi oleh: air, angin, dan es, berkolaborasi dengan latitude, ketinggian dan posisi relatif terhadap air laiut. Dapat dikatakan bahwa tiap daerah dengan iklim tertentu juga memiliki karakteristik pemandangan sendiri sebagai hasil dari erosi yang bekerja yang berbeda terhadap struktur geologi yang ada.
Torehan air terhadap lapisan batugamping yang keras dapat berupa aliran sungai yang permanen dan periodik, dapat juga merupakan alur drainase yang melewati bagian-bagian yang lemah. Sehingga membentuk cekungan-cekungan pada bagian yag tererosi dan meninggalkan bagian yang lebih tinggi yang susah tererosi. Ukuran dari cekungan dan tinggian ini bisa beberapa centimeter sampai beberapa kilometer.
 Morfologi Makro
Dibawah ini adalah beberapa bentuk morfologi permukaan karst dalam ukuran meter sampai kilometer:
1) Swallow hole : Lokasi dimana aliran permukaan seluruhnya atau sebagian mulai menjadi aliran bawah permukaan yang terdapat pada batugamping. Swallow hole yang terdapat pada polje sering disebut ponor. (Marjorie M. Sweeting, 1972). Pengertian ini dipergunakan untuk menandai tempat dimana aliran air menghilang menuju bawah tanah.
2) Sink hole : disebut juga doline, yaitu bentukan negatif yang dengan bentuk depresi atau mangkuk dengan diameter kecil sampai 1000 m lebih. (William B. White, 1988)
3) Vertical shaft : pada bentuk ideal, merupakan silinder dengan dinding vertikal merombak perlapisan melawan inclinasi perlapisan. (William B. White, 1988)
4) Collapse : runtuhan
5) Cockpit : bentuk lembah yang ada di dalam cone karst daerah tropik yang lembab. Kontur cockpit tidak melingkar seperti pada doline tetapi seperti bentuk bintang dengan sisi-sisi yang identik, yang menunjukkan bahwa formasi cone merupakan faktor penentunya. (Alfred Bogli, 1978)
6) Polje : depresi aksentip daerah karst, tertutup semua sisi, sebagian terdiri dari lantai yang rata, dengan batas-batas terjal di beberapa bagian dan dengan sudut yang nyata antara dasar/ lantai dengan tepi yang landai atau terjal itu.(Fink, Union Internationale de Speleologie)
7) Uvala : cekungan karst yang luas, dasarnya lebar tidak rata (Cjivic, 1901) : lembah yang memanjang kadang-kadang berkelak-kelok, tetapi pada umumnya dengan dasar yang menyerupai cawan. (Lehman, 1970)
8) Dry valley: terlihat seperti halnya lembah yang lainnya namun tidak ada aliran kecuali kadang-kadang setelah adanya es yang hebat diikuti oleh pencairan es yang cepat. (G.T. Warwick, 1976).
9) Pulau Jawa memiliki kawasan karst yang cukup spesifik yaitu karst Gunung Sewu, dimana bentukan bukit-bukit seperti cawan terbalik (cone hill) dan kerucut (conical hill) begitu sempurna dengan lembah-lembahnya. Bukit merupakan residu erosi dan lembahnya adalah merupakan daerah diaman terjadi erosi aktif dari dulu sampai sekarang. Bagian-bagian depresi atau cekungan merupakan titik terendah dan menghilangnya air permukaan ke bawah permukaan. Erosi memperlebar struktur (lihat geologi gua dan teori terbentuknya gua), kekar, sesar, dan bidang lapisan, dan membentuk gua-gua, baik vertikal maupun horisontal.
10) Gua-gua juga dapat terbentuk karena adanya mata air karst. Mata air (spring) karst ini ada beberapa jenis:
11) Bedding spring, mata air yang terbentuk pada tempat dimana terjadi pelebaran bidang lapisan,
12) Fracture spring, mata air yang terbentuk pada tempat dimana terjadi pelebaran bidang rekahan,
13) Contact spring, mata air yang terbentuk karena adanya kontak antara batu gamping dan batu lain yang impermiabel.
14) Disamping itu secara khusus ada jenis mata air yang berada di bawah permukaan air laut disebut dengan vrulja.

 Morfologi Mikro
Ada kawasan karst dengan sudut dip yang kecil dan permukaannya licin. Area ini dipisah-pisahkan dalam bentuk blok-blok oleh joint terbuka, disebut dengan grike-Bhs. Inggris, atau Kluftkarren-Bhs. Jerman. Bentukan-bentukan minor ini dalam bahasa Jerman memiliki akhiran karren (lapies-Bhs Perancis). Sering permukaan blok itu terpotong menjadi sebuah pola dendritic dari runnel dengan deretan dasar (round) dipisahkan oleh deretan punggungan (ridge) yang mengeringkannya kedalam grike terlebih dahulu. Juga terkadang mereka memiliki profil panjang yang hampir mulus. Bentukan ini disebut Rundkarren. Tipe lain adalah Rillenkarren yang memiliki saluran yang tajam, ujung punggungan dibatasi oleh deretan saluran berbentuk V. Biasanya nampak pada permukaan yag lebih curam daripada rundkarren, dengan saluran sub-paralel dan beberapa cabang. Microrillenkarren merupakan bentuk gabungan tetapi hanya memiliki panjang beberapa centimeter dan lebarnya 10-20 mm. Pseudo karren, memiliki bentuk sama dengan rundkarren dan rinnenkarren. Tetapi hanya terjadi pada granit di daerah tropik yang lembab.

GUA
Torehan air dan es adalah faktor utama yang memperlebar zonal lemah dilapisan batu gamping, sehingga terbentuk gua-gua. Ada banyak teori yang menjelaskan asal muasal terjadinya gua (teori klasik), namun sekarang sudah ada teori yang menjelaskan dan diterima secara umum. Perbedaan teori tersebut dikeluarkan oleh orang yang berasal dari kawasan karst yang berbeda, sesuai dengan karakteristik daerah tersebut. Lihat teori terbaru mengenai proses terlahirnya gua. Lihat juga speleogenesis.
Geomorfologi merupakan suatu studi yang mempelajari asal (terbentuknya) topografi sebagai akibat dari pengikisan (erosi) elemen-elemen utama, serta terbentuknya material-material hasil erosi. Melalui geomorfologi dipelajari cara-cara terjadi, pemerian, dan pengklasifikasian relief bumi. Relief bumi adalah bentuk-bentuk ketidakteraturan secara vertikal (baik dalam ukuran ataupun letak) pada permukaan bumi, yang terbentuk oleh pergerakan-pergerakan pada kerak bumi.
Konsep-konsep dasar dalam geomorfologi banyak diformulasikan oleh W.M. Davis. Davis menyatakan bahwa bentuk permukaan atau bentangan bumi (morphology of landforms) dikontrol oleh tiga faktor utama, yaitu struktur, proses, dan tahapan. Struktur di sini mempunyai arti sebagai struktur-struktur yang diakibatkan karakteristik batuan yang mempengaruhi bentuk permukaan bumi.
Proses-proses yang umum terjadi adalah proses erosional yang dipengaruhi oleh permeabilitas, kelarutan, dan sifat-sifat lainnya dari batuan. Bentuk-bentuk pada muka bumi umumnya melalui tahapan-tahapan mulai dari tahapan muda (youth), dewasa (maturity), tahapan tua (old age).Pada tahapan muda umumnya belum terganggu oleh gaya-gaya destruksional, pada tahap dewasa perkembangan selanjutnya ditunjukkan dengan tumbuhnya sistem drainase dengan jumlah panjang dan kedalamannya yang dapat mengakibatkan bentuk aslinya tidak tampak lagi. Proses selanjutnya membuat topografi lebih mendatar oleh gaya destruktif yang mengikis, meratakan, dan merendahkan permukaan bumi sehingga dekat dengan ketinggian muka air laut (disebut tahapan tua). Rangkaian pembentukan proses (tahapan-tahapan) geomorfologi tersebut menerus dan dapat berulang, dan sering disebut sebagai Siklus Geomorfik.
Selanjutnya dalam mempelajari geomorfologi perlu dipahami istilah-istilah katastrofisme, uniformiaterianisme, dan evolusi.
1. Katastrofisme merupakan pendapat yang menyatakan bahwa gejala-gejala morfologi terjadi secara mendadak, contohnya letusan gunung api.
2. Uniformitarianisme sebaliknya berpendapat bahwa proses pembentukkan morfologi cukup berjalan sangat lambat atau terus menerus, tapi mampu membentuk bentuk-bentuk yang sekarang, bahkan banyak perubahan-perubahan yang terjadi pada masa lalu juga terjadi pada masa sekarang, da seterusnya (James Hutton dan John Playfair, 1802).
3. Evolusi cenderung didefinisikan sebagai proses yang lambat dan dengan perlahan-lahan membentuk dan mengubah menjadi bentukan-bentukan baru.


A. PROSESE-PROSES GEOMETRIK
Proses-proses geomorfik adalah semua perubahan fisik dan kimia yang terjadi akibat proses-proses perubahan muka bumi. Secara umum proses-proses geomorfik tersebut adalah sebagai berikut :
a. Proses-proses epigen (eksogenetik)
1. Degradasi ; pelapukan, perpindahan massa (perpindahan secara gravity), erosi (termasuk transportasi) oleh : aliran air, air tanah, gelombang, arus, tsunami), angin, dan glasier.
2. Aggradasi ; pelapukan, perpindahan massa (perpindahan secara gravity), erosi (termasuk transportasi) oleh : aliran air, air tanah, gelombang, arus, tsunami), angin, dan glasier.
3. Akibat organisme (termasuk manusia)
b. Proses-proseshipogen (endoginetik)
1. Diastrophisme (tektonisme)
2. Vulkanisme
c. Proses-proses ekstraterrestrial, misalnya kawah akibat jatuhnya meteor.

A.1 Proses Gradasional
Istilah gradasi (gradation) awalnya digunakan oleh Chamberin dan Solisbury (1904) yaitu semua proses dimana menjadikan permukaan litosfir menjadi level yang baru. Kemudian gradasi tersebut dibagi menjadi dua proses yaitu degradasi (menghasilkan level yang lebih rendah) dan agradasi (menghasilkan level yang lebih tinggi).
Tiga proses utama yang terjadi pada peristiwa gradasi yaitu :
1. Pelapukan, dapat berupa disentrigasi atau dekomposisi batuan dalam suatu tempat, terjadi di permukaan, dan dapat merombak batuan menjadi klastis. Dalam proses ini belum termasuk transportasi.
2. Perpindahan massa (mass wasting), dapat berupa perpindahan (bulk transfer) suatu massa batuan sebagai akibat dari gaya gravitasi. Kadang-kadang (biasanya)efek dari air mempunyai peranan yang cukup besar, namun belum merupakan suatu media transportasi.
3. Erosi, merupakan suatu tahap lanjut dari perpindahan dan pergerakan masa batuan. Oleh suatu agen (media) pemindah. Secara geologi (kebanyakan) memasukkan erosi sebagai bagian dari proses transportasi.
Secara umum, series (bagian/tahapan) proses gradisional sebagai berikut landslides (dicirikan oleh hadirnya sedikit air, dan perpindahan massa yang besar), earthflow (aliran batuan/tanah), mudflows (aliran berupa lumpur), sheetfloods, slopewash, dan stream (dicirikan oleh jumlah air yang banyak dan perpindahan massa pada ukuran halus dengan slope yang kecil).
A.1.1 Pelapukan Batuan
Pelapukan merupakan suatu proses penghancuran batuan manjadi klastis dan akan tekikis oleh gaya destruktif. Proses pelapukan terjadi oleh banyak proses destruktif, antara lain :
1. Proses fisik dan mekanik (desintegrasi) seperti pemanasan, pendinginan, pembekuan; kerja tumbuh-tumbuhan dan binatang , serta proses-proses desintegrasi mekanik lainnya
2. Proses-proses kimia (dekomposisi) dari berbagai sumber seperti : oksidasi, hidrasi, karbonan, serta pelarutan batuan dan tanah. Proses dekomposisi ini banyak didorong oleh suhu dan kelembaban yang tinggi, serta peranan organisme (tumbuh-tumbuhan dan binatang).
Faktor-faktor yang mempengaruhi pelapukan antara lain :
1. Jenis batuan, yaitu komposisi mineral, tekstur, dan struktur batuan
2. Kondisi iklim dan cuaca, apakah kering atau lembab, dingin atau panas, konstan atau berubah-ubah.
3. Kehadiran dan kelebatan vegetasi
4. Kemiringan medan, pengaruh pancaran matahari, dan curah hujan.
Proses pelapukan berlangsung secara differential weathering (proses pelapukan dengan perbedaan intensitas yang disebabkan oleh perbedaan kekerasan, jenis, dan struktur batuan). Hal tersebut menghasilkan bentuk-bentuk morfologi yang khas seperti :
1. Bongkah-bongkah desintegrasi (terdapat pada batuan masif yang memperlihatkan retakan-retakan atau kekar-kekar),
2. Stone lattice (perbedaan kekerasan lapisan batuan sedimen yang membentuknya), mushroom (berbentuk jamur),
3. Demoiselles (tiang-tiang tanah dengan bongkah-bongkah penutup),
4. Talus (akumulasi material hasil lapukan di kaki tebing terjal),
5. Exfoliation domes (berbentuk bukit dari batuan masif yang homogen, dan mengelupas dalam lapisan-lapisan atau serpihan-serpihan melengkung).

Perubahan Fisika dan Kimia

Kata Kunci: Perubahan Fisika, Perubahan Kimia
Ditulis oleh Ratna dkk pada 12-04-2009
Perubahan yang melibatkan sifat fisika atau kimia.
Sifat Fisika
Sifat yang tidak mengubah sifat kimia suatu materi. Karakteristik fisika bau, kekerasan, titik didih, wujud materi.
Sifat Kimia
Sifat yang mengubah sifat kimia suatu materi. Menerangkan bagaimana suatu materi bereaksi dengan materi yang lain membentuk suatu materi baru.

Ciri-ciri yang mengindikasikan adanya perubahan kimia :
• Perubahan warna
• Perubahan bau
• Pembentukan gas
• Timbulnya cahaya
• Pembentukan endapan baru
• Perubahan pH.
Contoh :
Gula adalah senyawa yang mudah terurai (dekomposisi) dengan pemanasan menjadi senyawa yang lebih sederhana, misalnya karbon hitam (arang), yang tidak dapat terurai lagi baik secara fisika maupun kimia, tetapi dapat berubah struktur dan sifatnya menjadi grafit dan intan.

UNSUR-UNSUR GOLONGAN 16

Sifat kimia khas dari unsur golongan 16 adalah atom-atomnya memerlukan 2 elektron untuk mencapai konfigurasi gas mulia. Golongan 16 biasanya disebut golongan Kalkogen. Kecenderungan yang terjadi akibat bertambah besarnya nomor atom adalah:
1. bertambah besarnya jari-jari atom
2. titik didih dari atas ke bawah semakin besar,
3. titik lebur dari atas ke bawah semakin besar kecuali Unsur Polonium (254),
4. massa jenis dari atas ke bawah semakin besar.
Sifat fisika umum golongan 16
Nama unsure No atom Wujud pada suhu kamar Warna Massa atom konfigurasi
Oksigen 8 Gas Tak berwarna 16 1s2,2s2,2p4
Sulfur 16 Zat padat Kuning 32 (Ne10) 3s2,3p4
Selenium 34 Zat padat Merah atau abu-abu 79 (Ar18) 3d10,4s2,4p4
Tellurium 52 Zat padat Putih keperakan 128 (Kr36) 4d10,5s2,5p4
Polonium 84 Zat padat Kuning kehitaman 210 (Xe54) f14,5d10,6s2,6p4
Ciri fisik golongan 16
Nama unsur Massa jenis (g/cm3) Titik lebur (oC ) Titik didih (oC ) Struktur kristal Bilangan oksidasi
Oksigen 1,14 -218,8 -183 Kubus -2
Sulfur 2,07 119 445 orthorhombik -2,2,4,6
Selenium 4,8 217 685 Hexagonal -2,2,4,6
Tellurium 6,24 450 990 Hexagonal -2, 4,6
Polonium 9,2 254 960 - 2,4
OKSIGEN
Sifat Kimia Oksigen
Oksigen membentuk senyawa dengan semua unsur, kecuali gas-gas mulia ringan. Biasanya oksigen bereaksi dengan logam membentuk ikatan yang bersifat ionik dan bereaksi dengan bukan logam membentuk ikatan yang bersifat kovalen sehingga akan membentuk oksida.



Alotrop
o Dioksigen
Merupakan zat gas yang tidak berbau dan tidak berwarna. Dioksigen beraksi secara langsung dengan semua unsure kecuali gas mulia, sebagian unsure halogen dan beberapa logam tak aktif.
1.Pembuatan dioksigen
Di labolatorium, dapat dibuat dengan:
a. Penguraian suatu peroksida
b. Penguraian panas oksida logam
c. Penguraian panas garam-garam yang mengandung anion kaya oksigen, seperti kalium klorat(V) atau kalium nitrat (V)
d. Dengan elektrolisis
Di industri, dioksida dibuat dengan penyulingan udara cair.yang terdiri dari nitrogen dan oksigen cair.nitrogen cair akan tersuling terlebih dahulu.
2.kegunaan dioksigen
Dioksigen dipakai dalam peralatan oksigen dalam piranti rumah sakit, dalam produksi baja, plastik, dan tekstil, Sebagai penyokong kehidupan pada pesawat terbang, kapal selam, penerbangan luar angkasa, dan penyelaman dan dalam industry kimia organic dan anorganik.
o Trioksigen
Trioksigen merupakan zat berwarna biru muda yang mempunyai bau tidak enak,manis,seperti rumput yang baru di pangkas.trioksigen mengembun membentuk cairan biru pada suhu -112oC dan membeku jadi padat biru hitam pada -192oC. trioksigen merupakan oksidator yang sangat kuat (lebih kuat dari dioksigen) dan membentuk senyawa adisi dengan senyawaan organic yang mempunyai ikatan ganda.
1. Pembuatan trioksigen
Dibuat dengan membiarkan discas listrik bersuhu rendah melalui dioksigen. Discas listrik bersuhu rendah diperlukan untuk mencegah terjadinya peruraian. Pada proses ini terjadi konversi hingga 10% menjadi trioksigen,selanjutnya campuran gas ini dipisahkan melalui penyulingan karena trioksigen mempunyai titik didih yang lebih tinggi dari dioksigen.
2. kegunaan trioksigen
digunakan untuk bakterisida pada botol air minum dan kolam renang, pemutih pada bubr kertas dan tepung.
Oksida
Oksida ialah suatu senyawa biner dengan suatu unsure. Terdapat enam macam oksida, yaitu:
a) Oksida asam
Oksida asam adalah oksida dari unsur nonlogam dan oksida unsur blok d dengan bilangan oksidasi besar.

d) Oksida netral
Oksida ini tidak bereaksi dengan asam maupun basa, misal NO, N2O, dan CO.
e) Oksida campuran
Oksida ini merupakan campuran dari oksida sederhana, misalnya P3O4 merupakan campuran PbO (dua bagian) dan PbO2 (satu bagian).
f) Peroksida dan superperoksida
Oksigen membentuk peroksida H2O2, N2O2 dan BaO2 dengan bilangan oksidasi oksigen –1 serta RbO2, CsO2 dengan bilangan oksidasi oksigen –1/2.

BELERANG
1) Sifat Kimia Belerang
Belerang hanya memerlukan dua elektron lagi untuk mencapai konfigurasi s2p4 dari gas mulia. Jika belerang bereaksi dengan logam maka belerang bertindak sebagai penerima elektron. Belerang mudah bereaksi dengan semua unsur kecuali emas, platinum dan gas mulia. Reaksi-reaksi pada belerang, antara lain seperti berikut:

a. belerang mudah bereaksi dengan logam
contoh: Fe(s) + S (s) FeS( s)
b. dapat bereaksi langsung dengan beberapa unsure non logam misalnya fluorin, klorin, oksigen dan karbon
contoh:2S (s) + C (s) CS2 (l)
c. belerang dioksidasikan oleh asam nitrat pekat dan asam sulfat pekat membentuk sulfide dan sulfit.
d. Bila gas hydrogen dialirkan dalam bentuk gelembung melalui belerang yang meleleh, akan terbentuk hydrogen sulfide.
H2 (g) + S(s) H2S (g)
Alotrop
o siklooktabelerang (S8)
merupakan bentuk yang paling umum dialam dan berwarna kuning jerami.mempunyai susunan zigzag disekitar cincin.pada suhu diatas 95oC membentuk Kristal jarum dan dibawah suhu ini membentuk kristal chunky.
o Sikloheksabelerang (S6)
o Siklododekabelerang (S12)
o
Senyawa
Senyawa yang mengandung belerang antara lain: hidrogen sulfida, sulfida,belerang oksida,, asam sulfat, sulfit, sulfat,hidrogen sulfat,tiosulfat, peroksodisulfat, belerang dan heksafluorida.

Kegunaan belerang
Belerang adalah komponen serbuk mesiu dan digunakan dalam proses vulkanisasi karet alam dan juga berperaan sebagai fungisida. Belerang digunakan besar-besaran dalam pembuatan pupuk fosfat. Belerang digunakan untuk menghasilkan asam sulfat, bahan kimia yang sangat penting untuk agen sulfonasi.
Belerang juga digunakanuntuk pembuatan kertas sulfit dan kertas lainnya, untuk mensterilkan alat pengasap, dan untuk memutihkan buah kering. Belerang merupakan insultor yang baik.


SELENIUM
Selenium adalah suatu unsur Kimia dalam tabel periodik yang memiliki lambang Se dan nomor atom 34. Selenium menunjukkan sifat fotovoltaik, yakni mengubah cahaya menjadi listrik, dan sifat fotokonduktif, yakni menunjukkan penurunan hambatan listrik dengan meningkatnya cahaya dari luar (menjadi penghantar listrik ketika terpapar cahaya dengan energi yang cukup). Sifat-sifat ini membuat selenium sangat berguna dalam produksi fotosel dan exposuremeter untuk tujuan fotografi, seperti sel matahari. Selenium merupakan unsure nomn toksik namun senyawa selenium seperti asam selenida dan yang lainnya bersifat racun.

Selenium diperoleh dari memanggang endapan hasil elektrolisis dengan soda atau asam sulfat, atau dengan meleburkan endapan tersebut dengan soda dan niter (mineral yang mengandung kalium nitrat). Selenium juga ditemukan dalam beberapa mineral yang cukup langka seperti kruksit dan klausthalit
Alotrop

o Selenium kristal heksagonal, yang merupakan jenis paling stabil, berwarna abu-abu metalik
o Selenium amorf berwarna merah (bentuk serbuk) atau hitam (dalam bentuk seperti kaca).
o Selenium kristal monoklinik berwarna merah tua

Kegunaan
Digunakan dalam xerografi untuk memperbanyak salinan dokumen. untuk membuat kaca dan lapisan email gigi yang berwarna rubi. Juga digunakan sebagai tinta fotografi dan sebagai bahan tambahan baja tahan karat.


TELURIUM
Merupakan unsur yang jarang ditemukan dialam, biasanya ditemukan dalam bentuk senyawa telluride dari kalaverit dan logam lain. Telurium dapat didapat dari lumpur anoda yang dihasilkan selama proses pemurnian elektrolisis tembaga panas. Telurium memiliki warna putih keperak-perakan, dan dalam keadaan murninya menunjukkan kilau logam. Cukup rapuh dan bisa dihaluskan dengan mudah. Telurium dan senyawanya kemungkinan beracun dan harus ditangani dengan hati-hati. Hanya boleh terpapar dengan telurium dengan konsentrasi serendah 0.01 mg/m3, atau lebih rendah, dan pada konsentrasi ini telurium memiliki bau khas yang menyerupai bau bawang putih.
Kegunaan
Telurium memperbaiki kemampuan tembaga dan baja tahan karat untuk digunakan dalam permesinan. Penambahan telurium pada timbal dapat mengurangi reaksi korosi oleh asam sulfat pada timbal, dan juga memperbaiki kekuatan dan kekerasannya. Telurium digunakan sebagai komponen utama dalam sumbat peleburan, dan ditambahkan pada besi pelapis pada menara pendingin. Telurium juga digunakan dalam keramik. Bismut telurrida telah digunakan dalam peralatan termoelektrik.


POLONIUM
Polonium adalah suatu unsur Kimia dalam tabel periodik yang memiliki lambang Po dan nomor atom 84.Unsur radioaktif yang langka ini termasuk kelompok metaloidengan Telurium yang memiliki sifat Kimia yang mirip dengan Telurium dan Bismut. Polonium merupakan unsur yang sangat jarang di alam.polonium bisa didapatkan dengan menggunakan tembakan neutron berintensitas tinggi dalam reaktor nuklir. Polonium mudah larut dalam asam encer, tapi hanya sedikit larut dalam basa. Garam polonium dari asam organik terbakar dengan cepat. Dan dapat direduksi menjadi logam oleh halida amina. Polonium merupakan unsure yang bersifat radioaktif dengan titik cair rendah dan merupakan pemancar alpha dengan masa paruh waktu 138.39 hari. Satu milligram memancarkan partikel alfa seperti 5 gram radium.
Energi yang dilepaskan dengan pancarannya sangat besar (140 W/gram), setengah gram polonium mencapai suhu di atas 500oC. selain itu juga menghasilkan sinar gamma dengan kecepatan dosisnya 0.012 Gy/jam. Sejumlah curie (1 curie = 3.7 x 1010Bq) polonium mengeluarkan kilau biru yang disebabkan eksitasi di sekitar gas.
Kegunaan
Polonium untuk digunakan sebagai sumber panas yang ringan sebagai sumber energi termoelektrik pada satelit angkasa.
Polonium dapat dicampur atau dibentuk alloy dengan berilium untuk menghasilkan sumber neutron. Unsur ini telah digunakan dalam peralatan untuk menghilangkan muatan statis dalam pemintalan tekstil dan lain-lain; bagaimanapun, sumber beta termasuk yang paling sering digunakan karena tingkat bahayanya yang lebih rendah. Polonium yang digunakan untuk tujuan ini harus tersegel dan terkontrol, untuk mengurangi bahaya terhadap pengguna karena sangat berbahaya untuk ditangani meski hanya sejumlah milligram atau mikrogram. Diperlukan peralatan khusus dan kontrol yang ketat untuk menanganinya. Kerusakan timbul dari penyerapan energi partikel alfa oleh jaringan makhluk hidup.
.















Peta konsep

Oksigen sifat kimia
Alotrop dioksigen
trioksigen
oksida
kegunaan
Belerang sifat kimia
Alotrop S8, S6, S12
Kegunaan
Unsur Selenium sifat kimia
golongan Alotrop Kristal hexagonal
16 Amorf
Kristal monosiklik kegunaan

Tellurium sifat kimia kegunaan

Polonium sifat kimia
kegunaan

THE EFFECTS OF A DESIGNED STUDENT-CENTERED INSTRUCTION ON INDONESIAN & JAPANESE HIGH SCHOOL STUDENTS’ LEARNING OF ACIDS-BASES AND PERCEPTIONS

Abstract

This study examines the effectiveness of a designed student-centered instruction in improving students’ understanding of acids and bases. The instruction was designed based on constructivist, inquiry and context-based approaches. A triangulation mixed methods design was employed included a quasi-experiment with pretest and posttest. The participats were two classes of senior high school students from Indonesia, chosen as treatment and control groups and a class of grade 10 Super Science High School students from Japan. Analysis of covariance followed by an unpaired sample t-test for mean gain scores were performed to analyze the Indonesian students’ scores on the achievement test and a normalized gain score was calculated for Japanese students’ achievement. A descriptive analysis was performed to analyze the responses on both self-evaluation and open-ended questionnaires. Results of this study indicate that the designed student-centered instruction group significantly outperformed the traditional group in understanding of acids and bases. Analysis of students’ responses on the questionnaires show that most of the students (97%) in the treatment goup were actively involved in the unit, enjoyed working with hands-on activities, and were very interested in participating in the activities. The students also felt their understandings of the concepts have improved. This study was also effective when it was implemented in Super Science High School students in Japan and most of the students (97%) enjoyed the teaching and learning process and most of them (80%) felt that their understandings of the concepts had improved.This study has implications for both Indonesian and Japanese senior high schools.


Key words: designed student-centered instruction, effectiveness, constructivist, inquiry, context-based approach, achievement, perceptions


INTRODUCTION
Results of the Third International Mathematics and Science Study (TIMSS) and the Programme for International Student Assessment (PISA) indicate that Indonesian students’ performance on mathematics and science is relatively poor compared to those of other countries, including Japan (Lemke et al., 2004; Gonzales, 2000). This reality is one of the impetuses of the Indonesian government to reform science education. The essence of the reform program lies in a learning paradigm, educational decentralisation and competence-based curriculum (Sidi, 2008). One of the government’s reform initiatives was to launch a new curriculum in 2006. The new 2006 curriculum suggests that pedagogy implemented in all school levels should be student-centered with an emphasis on creativity, competency, life skills and hands-on experiences (BSNP, 2007). There have been some efforts to realize this curriculum expectation. For example, the educational community and reseachers have introduced a contextual teaching and learning (CTL) approach and an active, creative and enjoyable teaching and learning approach (in the Indonesian language it is called PAKEM) for changing school instruction. Such reform efforts, however, are rare for high school level. Furthermore, traditional instruction for science including chemistry in Indonesian high school level is mainly lecture-based and students occasionally conduct chemistry laboratory activities in a very structured form of inquiry in order to verify what the textbook or instructor has indicated to be the expected result of an experiment. Limitations of learning science, in the absence of inquiry experiences, are well known. When science is presented as a body of knowledge, students are discouraged from developing their own explorations and explanations of observed phenomena (see Trumbull et al., 2005). In this study, an innovative science instruction to fit within the new 2009 chemistry curriculum and to fullfil the curriculum expectation was designed, which explored the concepts of acids and bases. The innovative science instruction, which is called designed student-centered instruction, met the requirements of the existing curriculum and was conducted under all the time and other restrictions imposed by the Indonesian system. This designed student-centered instruction was a teaching-learning sequence oriented toward contemporary approaches suggested by the chemical education research literature. It included the use of hands-on/inquiry-oriented and collaborative activities connected to students’ everyday life materials and environmental issues. According to Wise (1996) any innovative science instruction should be a mixture of teaching strategies and no one strategy is as powerful as utilizing a combined strategies approach. If students are placed in an environment in which they can actively connect the instruction to their interests and present understandings and have an opportunity to experience collaborative scientific inquiry under the guidance of an effective teacher, achievement will be accelerated. Therefore, this study examines whether a designed student-centered instruction was more effective in teaching acids and bases than traditional instruction, and whether this design was also effective when it was implemented for Japanese senior high school students.
THEORETICAL BACKGROUND
Constructivist Approach
Recent research in science education has been dominated by a constructivist perspective of learning. According to this perspective, students do not passively absorb information, but rather, meaningful learning involves the active creation and modification of knowledge structures (Carey, 1985). So, learning is considered as an individual process that involves linking new ideas and experiences with what the learner already knows through interactions with the physical and/or social environment (Liang and Gabel, 2005). Basically, it stresses the thought processes of the learner and assumes that prior knowledge, attitude, motivation, and learning style affect the learning process (Spencer, 1999). Table 1 provides a summary of the differences in emphases between traditional and constructivist learning environments.
Table 1. Elements of emphases in traditional and constructivist learning environments
Traditional Constructivist
Instructional emphasis
Teaching, knowledge reproduction, independent learning, competition.
Learning, knowledge construction, collaboration, reflection
Instructor roles
Expert, source of understanding, lecturer
Collaborator, facilitator, encourager, community builder
Student roles
Passive, listener, consumer of knowledge, note taker
Active, collaborator, constructor of knowledge, self-monitoring
Assessment
Fact retention
Authentic knowledge application, portfolio, projects, performances.
*Modified from Rovai (2004)


Inquiry Approach
Science including chemistry has been characterized as consisting of aspects of content and scientific process (see Bass, Constant & Carin, 2009). Content consists of statements about nature, including natural entities, the theories and concepts used to understand and explain these entities. Process consists of the practice of how science is done by scientist involving the interplay of experiment, prediction, hypothesis generation, and communication of results within a scientific community. Therefore, students in their schools should learn the content as well as experience the process.
A connection of scientific process and learning around the idea of ‘‘inquiry’’ is already well known, and a key component of pedagogical constructivist approaches is incorporated in the idea of ‘‘inquiry learning.’’(Wink, 2006). This means that inquiry instruction supports a constructivist approach to learning science (Bass, Constant & Carin, 2009: p.4). According to NSES (NRC, 1996), scientific inquiry describes the diverse ways in which scientists study the natural world and propose explanations based on the evidence derived from their work. Inquiry also refers to the activities of students in which they develop knowledge and understanding of scientific ideas, as well as an understanding of how scientists study the natural world. Therefore, providing students with authentic opportunities to conduct science inquiry is expected to enhance their abilities to successfully evaluate complex scientific ideas. Conversely, lack of experiences with scientific inquiry restricts the success with which students evaluate scientific knowledge claims (Trumbull et al., 2005).
Learning outcomes associated with inquiry dimensions of science include generating a hypothesis, developing a plan for gathering data, and constructing arguments based on evidence. Through the practice of inquiry, students acquire knowledge in a more meaningful way (Germann, Haskins and Auls, 1996). Students need ample opportunities to practice the science processes within a variety of investigations. Together with appropriate feedback and modeling, students should become more proficient and independent. If teachers and students make connections between the domain-specific contexts of the laboratory such as chemistry and more general contexts, then many students will be able to apply the science processes outside of the classroom (Germann & Aram, 1996).
Context-Based Approach
The notion of context-based approach comes from recent attempts to reform the design of courses in chemical education in order to address a number of inter-related problems (i.e., context here is used as the basis for curriculum design and classroom teaching) (see Driver, 2006; Schwartz, 2006). According to Pearsall (1999) context means “the circumstances that form the setting for an event, statement or idea, and the terms in which it can be fully understood” and “the parts that immediately precede or follow a word or passage and clarify its meaning” A context must provide a coherent structural meaning for something new that is set within a broader perspective. These descriptions are consistent with the function of “the use of contexts” in chemical education in that students should be able to provide meaning to the learning of chemistry and they should experience their learning as relevant to some aspects of their lives and be able to construct coherent “mental maps” of the subject. Bennett (2003 in Gilbert, 2006) has provided evidence from research into context-based curricula, such as pupils’ interest and enjoyment of their science lessons generally increase when they use context-based materials and follow context-based courses; context-based materials help pupils see and appreciate more clearly links between the science they study and their everyday lives; pupils following context-based instruction learn science concepts at least as effectively as those following more traditional instruction.

Designed Student-Centered Instruction Based on Constructivist, Inquiry and Context-based Approaches.
Designed student-centered instruction consists of a number of approaches, including a constructivist approach, a hands-on inquiry approach, a context-based approach, and concept map & interactive-direct approaches. The major approaches used for the design, however, were the constructivist, hands-on inquiry and context-based approaches. Table 2 provides a description of designed student-centered instruction involving the learning activities and and the outcomes in each phase.
Table 2. Learning activities, objectives and outcomes in each phase of a designed student-centered instruction.
Phase Learning activities Learning objectives Outcomes
I Introduction
• Reading a concept map
• Seeing a connection between the concept being learned and students’ daily lives/environment.

• Connect students’ prior knowledge and the concepts being learned
• See interrelationship between concepts and their usefulness
• Students’ logical conceptual framework.
• Meaningful understandings of the concepts.

II Hands-on Inquiry Activity
• Planning and discussing an experiment in a group
• Consulting the experiment plan to the instructor
• Conducting an experiment
and discussing data collected within the group

• generate a hypothesis
• develop a plan for collecting data
• construct an argument based on evidence
• An investigative knowledge
• An argumentation skills
III Class Discussion
• Sharing experimental data with the whole class
• Negotiate knowledge or concept

• New knowledge or concept
IV Application
• Applying new concepts and inquiry skills to a new but similar situation.
• see more clearly the link between concepts and their daily-life
• Meaningful understanding of the concepts


Phase 1. Introduction. Each lesson was initiated by presenting a concept map about acids and bases and by showing some examples of materials around students’ daily lives. A concept map is an instructional tool to present concepts and to show clearly the connections between the concepts. The concept map in this study was used as an advance organizer to help students accomplish meaningful learning and was designed in the light of what a student already knew or didn’t know about a concept (see Berg, 2006). The use of concept maps has been shown to facilitate learning (Hughes and Hay, 2001). In introducing a new subtopic on acids and bases we always began with a concept map. After presenting the concept map, we showed some examples of materials around student’s daily lives such as a lemon and soap, in teaching the lesson of characteristic of acids and bases. This activity was intended to make students aware that there was a connection between what they would learn in the classroom and in their daily lives and also to engage students’ attention and enthusiasm towards learning chemistry.
Phase 2. Hands-on Inquiry Activity. This activity was intended to give students direct experiences of engaging in the scientific process. This study used a fourth level of inquiry according to LeRoy & Lee (2008) in which in the inquiry process, questioning activity was innitiated by the teacher, and planning, implementing, concluding and reporting were carried out by the students. In the lesson of characteristic acids and bases, for example, students were invited to identify whether unknown solutions of A, B, and C were acids, bases or neither acids or bases. Students worked in their small groups cooperatively and discussed their inquiry plan written on their worksheets. They had to formulate the purposes and hypotheses of their investigation, the equipment and chemicals they would use and the steps of their investigation. Before conducting the investigation, students discussed their investigation plan with the facilitator/teacher and then they carried out their plan and discussed the results within their own group before making a report. According to Chiappetta & Koballa (2006), the dynamics of group work can stimulate and sustain inquiry in many situations better than individual work. Students will find a great deal of meaning in chemistry lesson when their knowledge is constructed during productive, small, collaborative group activities. Futhermore, the group work can enhance student problem solving activity as well as concept development (Lumpe, 1995).
Phase 3. Class Discussion. This activity was intended to encourage students to explain their possible solutions or answers with reference to their previous activity. Students had to exchange their ideas with other groups by writing their answers on the blackboard or by making presentations. The teacher, as facilitator guided students’ discussion by asking questions for justification (evidence) and clarification from students and used students’ previous experiences as the basis for explaining concepts.
Phase 4. Application. This activity was meant to encourage students to apply or extend their concepts or skills to a new but similar situation. In the lesson on characteristic of acids and bases, for example, we gave tasks to the students to investigate whether materials around their home could be considered acids or bases. They brought the materials to the classroom and used previous information/skills to ask questions, designed their experiments and found out the answer to their question. We provided guidance for any difficulties students faced when it was needed. In a lesson about the strength of acids and bases, we showed some pictures connected to acid rain and asked them to explain the causes of the environment al damage shown in the pictures. The activities in the application phase related to students’ daily lives and environment issues. Students would see that what they learned in the classrom related to their daily lives and their learning would be meaningful. It is important that students have multiple opportunities to practice using the concepts they have learnt, in order to establish the concepts in their long-term memory (Nuthall, 1999).
Designed student-centered instruction was used to teach the lessons on characteristics and strength of acids and bases, whereas interactive-direct instruction was utilized to teach the lessons on definition, neutralization and pH of acids and bases.
RESEARCH QUESTIONS
This study focuses on an examination of whether chemistry concepts, especially acids and bases, are made visible and meaningful to high school students using designed student-centered instruction. In the context of this study, the following research questions are investigated.
1. Is designed student-centered instruction based on constructivist, hands-on inquiry and context-based approaches, effective in increasing Indonesian students’ learning achievement?
2. What are the Indonesian students’ perceptions about their roles in the group and about the teaching and learning process?
3. Is designed student-centered instruction based on constructivist, hands-on inquiry and context-based approaches, effective in increasing Japanese students’ learning achievement?
This study uses the terms of students’s learning achievement and perception. Students’ learning achievement means the ability of students to answer the achievement test on acids and bases in terms of cognitive aspects. Whereas, according to Pearsall (1999) perception means “a way of regarding, understanding, or interpreting something”. In this study, students’ perception refers to how students regard, understand and interpret their roles in group functioning and their view of the teaching and learning process.


HYPOTHESIS OF THE STUDY
The following null hypothesis was tested at the 0.05 a-level.
Ho = There is no statistically significant difference in students’ achievement on the topic of acids and bases between students taught using designed student-centered instruction and those taught in the traditional teaching method.
METHODOLOGY
Design
This study used a triangulation mixed methods design, in which both quantitative and qualitative data were collected simultaneously, both datasets analyzed separately, the results compared from the analysis of both datasets, and an interpretation made as to whether the results support or contradict each other (Creswell, 2008). This study includes two steps:
1. A quasi-experiment was designed with treatment and control groups and pre-test and post-test design as shown in Table 2. This design was conducted for Indonesian senior high school.
Table 2. Quasi experiment design
Group Pre-test Treatment Post-test
Experiment (E) O1 X O2
Control (C) O1 — O2
*O1 is pretest; O2 is post-test; and X is treatment.
2. The similar designed student-centered instruction was implemented for Japanese senior high schools.
Participants
The participants in this study consisted of Indonesian and Japanese senior high school students. Two classes of grade 11 who majoring in science from a senior high school in Indonesia were chosen as the sample in this study. One class was treated as an experimental group which consisted of 36 students (13 boys, 23 girls), while another class was treated as a control group which consisted of 38 students (13 boys, 25 girls). The students had an average socioeconomic status and achievement level compared to other schools within the country. The traditional teaching-learning process utilizes a direct instruction and a textbook-based approach. Laboratory activities and demonstration are mostly conducted to confirm concepts which have been learned in the classroom and in the form of structured inquiry like “cookbooks”.
The participants from Japan were a class of grade 10 students of a Super Science High School (SSH) in Okayama prefecture, Japan. This students had a chemistry in English class where in this class the chemistry topic is basically delivered in English. The number of students was 35 students ( 22 boys and 13 girls). The students had an average socioeconomic status and achievement level compared to other schools within Japan.
Limitations
The external validity of this study was limited in that the study was conducted only in a high school both in Indonesia and Japan and there was no class for control group for Japanese case. The application of this designed student-centered instruction was restricted by the school schedule and the sub-topics: characteristics, definition, strength of acids and bases, neutralization and pH.
Instruments
There were three research instruments utilized in this study. These instruments were an achievement test, a self-evaluation questionnaire and an open-ended questionnaire which measured students’ understanding of acids and bases, students’ perception of their roles in group functioning and students’ perceptions on the teaching-learning process, respectively.
An Achievement Test of Acids and Bases (ATAB). The ATAB was an open ended test, consisting of twelve short-answer questions on acids and bases. The concepts investigated in the ATAB are presented in Table 3 and the examples of questions can be seen in Electronic Suplementary Materials (ESM) A.
Table 3. Concepts investigated in the ATAB
No Concepts Question no.
1 Characteristics of acids and bases 1, 5 & 8
2 Definition of acids and bases 6 & 10
3 Strength of Acid and Base 2, 9, 12
4 Neutralization 4 & 7
5 pH 3 & 11

A self-evaluation questionnaire. This questionnaire was adapted from Llewellyn (2002), consisted of thirteen statements using Likert-type ratings with four options (usually, often, sometimes, and rarely). The instrument was constructed to quantify students’ perceptions of their roles in their group functioning and their skills in the inquiry process. The self-evaluation questionnaire is a means to collect feedback about how students perceive their individual and group performances and it can provide a window into students’ perceptions about how well they did on the chemistry exploration. A self-evaluation also offers the students the opportunity to reflect on how they might improve their performances if they were to repeat a task for the second time (Llewellyn, 2002). The examples of questions on the self-evaluation instrument are provided in ESM B.
An open-ended questionnaire on perceptions towards the teaching-learning process. To obtain information regarding students’ perceptions towards designed student-centered instruction, an open-ended questionnaire was administered to students in the experimental group at the end of the study. The questionnaire consisted of four questions. Questions no. 1 through no. 3 were intended to gain information about students’ perceptions about the teaching learning process, whereas question no. 4 was intended to gain information on what students’ think are the best ways to teach chemistry. The questions on the questionnaire are provided in ESM C.
The three research instruments were given to three experts for content validity inspection. The questions on the instruments were modified according their comments. To examine internal consistency reliability, Cronbach’s alpha (Fraenkel & Wallen, 2006) was computed for the achievement test (  = 0.789) and for self-evaluation questionnaire ( = 0.785). These reliability values were adequate for use in the study. Inter-rater examination was conducted for the qualitative data from the open-ended questionnaire. The second rater was a graduate student in chemical education research with some previous experience in chemical education. The initial reliability of the classifications of responses, measured as a percentage of agreement, was 95%. All initial disagreements were resolved through discussion.
Treatment
a. Treatment for Indonesian Senior High School Students
The experimental group received the lessons on acids and bases in the chemistry laboratory in which students were treated using designed student-centered instruction as described earlier, whereas the control group received traditional instruction which is relatively more dependent on lecture and textbooks. The duration of the teaching-learning process was two weeks (8 x 45 minutes) in both classes. The students in the experimental group were taught by the researcher, while the students in the control group were taught by a chemistry teacher in the school. Pre-test and post-test were administered to both experimental and control group before and after the treatment. The study was conducted in February 2007.
b. Treatment for Japanese Senior High School Students.
A class of grade 10 of a Super Science High School received the lesson on acids and bases in the chemistry laboratory using designed student-centered instruction which is similar to those implemented in Indonesian senior high school. The lessons was delivered in English by the researcher. The duration of the teaching-learning process was two weeks (8 x 45 minutes). The study was conducted in November 2006.
Data collecting procedures
a. Procedures for Indonesian Senior High School
We administered three research instruments for the Indonesian senior high school students. Before the study began, all students in both control and treatment groups took the achievement test (pretest) on acids and bases and they took the same test (posttest) at the end of the treatment. The achievement test took 40-45 minutes to complete. Students in the treatment group also took the self-evaluation questionnaire and an open-ended questionnaire collected after the study had finished.
b. Procedures for Japanese Senior High School.
We administered two research instruments for the Japanese senior high school students. Before the study began, the students took the achievement test (pretest) on acids and bases and they took the same test (posttest) at the end of the treatment. The achievement test (ATAB in Japanese version) took 40-45 minutes to complete. Students took also the open-ended questionnaire (in Japanese) when the study had finished.
Data Analysis
Quantitative data consisted of pre- and post-test scores, percentages from the self-evaluation responses and the open-ended questionnaire responses about the teaching and learning process. Qualitative data consisted of students’ statements in the open-ended questionnaire. To answer the research question no. 1, we need to examine the effect of the treatment, pre- and post-test scores of the treatment and control groups were analysed statistically (i.e., calculated by SPSS software) using one-way analysis of covariance (ANCOVA) with significance level set at 0.05 with the pretest as covariate and followed by an unpaired sample t-test for mean gain score. To answer the research question no. 2, students’ self-evaluations were analyzed and presented in percentages and students’ perceptions towards the teaching and learning process were presented both in percentage and descriptive form. To answer the research question no. 3, a normalized gain score by Hake (Hake, 2008) was applied for the pre- and posttest scores from Japanese students’ achievement test to roughly measure the effectiveness of designed student-centered instruction. The normalized gain score was used here because the we had only a treatment class and cannot set up a control group. In this study, the Japanese gain score was compared with the Indonesia gain score. The gain score can be calculated by simply the absolute gain divided by the maximum possible gain:





Interpretations: "High-g" instructions as those with () > 0.7;
"Medium-g" instructions as those with 0.7 > () > 0.3;
"Low-g" instructions as those with () < 0.3. RESULTS The central purpose of this study is to design and evaluate designed student-centered instruction which is considered appropriate for the Indonesian high school context. The designed instruction has been described earlier. The following results are discussed. The Effect of Designed Student-Centered Instruction on Students’ Achievement in Chemistry. An analysis of covariance (ANCOVA) was conducted to compare the groups in terms of the posttest scores obtained from the Achievement Test of Acids and Bases (ATAB), using pretest scores as a covariate. A level of 0.05 was used to test for significance between groups. The mean scores and the standard deviations for the ATAB for the treatment and traditional instruction groups are presented in Table 3. Output of Lavene’s test shows that the groups have F= 0.190; df1=1; df2= 72 and p-value = 0.665. A p-value > 0.05, means that the variances of dependent variable are equal across groups.
Table 3. Adjusted ATAB mean scores obtained by students
Group Mean Standard Deviations N
Treatment 44.06 4.548 36
Control 36.63 4.647 38

ANCOVA procedure was used to confirm if the treatment group (T) and control group (C) scores were significantly different. The results are shown in Table 4. The adjusted mean scores in the ANCOVA are shown in Table 5.
As shown in Table 4, the p-value of the pre-test is 0.005 < 0.05 -level. This means that the pre-test makes a statistically significant contribution to the variation of achievement related to acids and bases as measured by posttest. Moreover, ANCOVA results shows F= 46.579 with p-value = 0.000 < 0.05 -level which means that Ho is rejected. Thus the designed student-centered instruction make statistically significant contribution to the achievement on acids and bases measured by posttest. Table 4. One-way ANCOVA of post-test ATAB scores with pre-test score as covariate Sum of square Df Mean square F P-value Pre-test (covariate) 157.933 1 157.933 8.216 0.005 Designed student-centered instruction (treatment) 895.364 1 895.364 46.579 0.000 Error 1364.798 71 19.223 Corrected total 2541.622 73 a. R Squared = 0.463 (Adjusted R Squared = 0.448) Table 5. Adjusted ATAB mean scores obtained by students Group Mean Std. Error 95% Confidence Interval Lower Bound Upper Bound Treatment (T) 43.850a 0.734 42.386 45.314 Control (C) 36.826a 0.714 35.401 38.251 a. Covariates appearing in the model are evaluated at the following values: Pretest = 28. 07. A further comparison was needed to check the mean gain of the students from the pre-test to the post-test for the treatment group and the control group 1 (See Table 6). Table 6. Comparison of the mean scores and mean gain obtained by students in ATAB Overall(N= 74) Treatment group (T) Control group (C) Pre-test mean 28.09 28.83 27.34 Posttest mean 40.34 44.06 36.63 Mean gain 12.3 15.2 9.29 Table 6 shows that the treatment group (T) has a higher mean gain score than the control group (C). A paired sample t-test between mean gain scores of T and C groups indicates a significant difference in mean gains, t = -4.05856, P-value < 0.05. Thus the group taught using the designed student-centered instruction has a higher mean gain score than the control group. The hypothesis that there is no statistically significant difference in chemistry achievement between students taught using designed student-centered instruction and those taught using the traditional teaching method is rejected at the 0.05 -level. Therefore, using the designed student-centered instruction based on the constructivist, inquiry-based, context-based approaches improves students’ performance in chemistry more than when the students are taught in the traditional teaching method. Students’ Self-Evaluation An analysis of quantitative data on the self-evaluation provides some information about students’ perceptions of their roles in their group functioning and their skills in the inquiry process or how well they did on chemistry exploration throughout the series of inquiry-based activities. The results of self-evaluation are presented in ESM B. Data from self-evaluation show that: • Question no. 1, 2, 3 and 8 were dealing with students’ doing experimental activities. The average percentage of students choosing the options were 81% on the option “always” and “often” and 12% on the options “sometimes” and “rare” (M= 3.23, SD= 0.14). We interpret this as meaning that most students felt very confident in dealing with experimental activity, such as: handling a solution properly; making an accurate observation; following their plan and using the equipments and chemicals appropriately; • Question no. 7 and 9 were dealing with students’ use of notebook, textbook and other resources. The average percentages of students choosing the options were 64% on the options “sometimes” and “rare” and 32% on the option “always” and “often” (M= 2.32, SD= 0.18). This means that many students do not rely much on their note/workbook to record observation and measurement and to use their resources to collect information for the experiment; • Question no. 4 to 6 and no. 10 to 13 were dealing with students interaction in the group activities. The average percentage of students choosing the options were 75% on the options “always” and “often” and 21% on options “sometimes” and “rare”. This data means that most of the students were very confident in working in their group activities and in doing presentations. In this case, students felt that they participated in group discussion productively, listened to other group members and respected their ideas, and shared in group work. Furthermore, students felt confident in presenting to share what they had learned with others. They, shared responsibility for the presentations, made good eye contact and projected their voices during presentations. Students Perceptions of the Teaching-Learning Process. An analysis of students’ responses on the open-ended questionnaire provided some information on students’ perceptions about the teaching-learning process in the treatment class. A classifications of students’ responses are presented in ESM C. • In question no. 1, students were asked to give their opinions as to whether the teaching learning process was enjoyable or not. The data show that almost all students (35 students or 97%) said that the teaching learning process was enjoyable. They gave reasons, for example, a lot of practical activities (30%); relate to daily lives (19%); easy to understand (28%); the teaching method was interesting and different from ordinary method (14%). • In question no. 2, students were asked to give their opinion as to whether their understandings about acids and bases had improved. The data show that almost all students (35 students or 97%) said that their understanding about acids and bases had improved. They gave reasons, for example, through practical activity the topic was easy to understand and to remember (39%); through the teaching method students could share ideas/thinking so that the topic was easily understood (41%); teaching method was interesting and made students more active (14%). • In question no. 3, students were asked to give their opinion about what the best way to teach chemistry was so that they could understand chemistry concepts well. The data indicate: 10 students (28%) liked this method/way; 13 students (36%) suggested more experiments and 6 students (16%) liked a step by step of teacher’s explanation. • In question no 4, students were asked to consider the most important concept on acids and bases they just experienced. The data show: 6 students (16%) indicated the strenght of acids and bases; 9 students (25%) preferred identification of daily life materials as acids, bases or neutral; 5 students (14%) prefered pH and concentration and 6 students (16%) said that all concepts were important. The Effect of Designed Student-Centered Instruction on Japanese Students’ Achievement An analysis of the normalized gain score was conducted for pre-and posttest results to roughly measure the effectiveness of designed student-centered instruction. Table 7 shows the gain score results from both Japanese and Indonesian students. Table 7. The normalized gain scores between Indonesian and Japanese students Japanese Indonesian Pre-test 22.77 28.83 Posttest 36.86 44.06 Gain score < g > 0.36 0.46

The data reveals that both Japanese and Indonesian students achieved medium gain scores = 0.36 (ranged between 0.7 > () > 0.3). This means that designed student-centered instruction was effective in improving both Japanese and Indonesian students’ achievement. The Japanese gain score, however, was lower than Indonesian gain score.
An analysis of students’ responses on the open-ended questionnaire provided some information on students’ perceptions about the teaching-learning process in the treatment class. Examples of students’ responses on the questions no 1 and 2 will be presented here.
In question no. 1, students were asked to give their opinions as to whether the teaching learning process was enjoyable or not. The data show that almost all students (34 students or 97%) said that the teaching learning process was enjoyable. They gave reasons which was connected to: communication in English (37%), experiment (20%), knowledge/experiences (23%), daily life materials (11%). The following are examples of students’ responses:
• “English was difficult but chemistry content was easy to understand”.
• “ Chemistry in English was the first time and I learnt many things”.
• “At the beginning English was difficult, but it became enjoyable”.
• “I knew pH values of various solutions in daily life. I became intererested in daily life materials”.
• “Because new knowledge I got and chemistry in english was enjoyable”.
• ”Experiments were enjoyable and BTB colour was beautiful”.
• “Almost all I have learnt but pH information was very detail”.

In question no. 2, students were asked to give their opinion as to whether their understandings about acids and bases had improved. The data show that most students (28 students or 80%) said that their understanding about acids and bases had improved and 7 students (20%) said that their understanding about acids and bases had not improved. Their reasons were varied and they mentioned such as: “new knowledge”, “experiments”, “ good lessons”. The following are examples of students responses:
• “I learnt many things eventhough in a short time”.
• “Various experiments on charachteristic of acids and bases”.
• “ I understood deeper from different view and good reviews”.
• “ I understood deeper because of new experiences”.
• “ Due to all english lesson, some parts are difficult to understand”.
• “ I didn’t understand due to difficulty of the lesson”.


DISCUSSION
This study was conducted to investigate the effectiveness of two methods of teaching acids and bases (i.e., designed student-centered instruction and traditional instruction) for senior high school students. The results of this study indicate that designed student-centered instruction (treatment) group significantly outperformed traditional (control) group in understanding key aspects and concepts involving acids and bases. This design was also effective in improving understanding when it implemented for Japanese senior high school students with a medium gain score, eventhough the Japanese students’ gain score was lower than Indonesian students’ gain score.
Possible reasons for the observed difference between the treatment and the control group might include the value associated with alternative ways of acquiring knowledge in science, particularly inquiry using hands-on/practical and context-based activities. During the implementation of this designed student-centered instruction, students learned through their own actions and reactions by being involved in hands-on/practical activities. Analyses of questionnaire responses in the present study suggested that the majority of students (about 97%) in the designed student-centered instruction were actively involved in the unit, enjoyed working with hands-on activities, and were very interested in participating in the activities. They also felt their understandings of the concepts had improved. Students reasoned that through practical activity (39% of students) or through this teaching method (41% of students), the concepts were easily understood. Futhermore, some students (14%) said that this teaching method was interesting, different with ordinary teaching method and made students more active. Some students (19%) enjoyed the teaching learning process because the activity related to their daily lives so that students might feel that the concepts studied were relevant and meaningful for them. This was supported by other students (25%) who preferred to choose “identification of daily lives materials as acid, base or neutral” as the most important concept they had learned.
In the designed student-centered group students explored new materials and phenomena that raised questions and encouraged them to seek answers. Student explorations involving planning, gathering and analyzing data allowed them to test their alternative hypotheses/prediction. By involving in hands-on activities students were helped to examine the adequacy of their prior conceptions and this forced them to argue about and test those conceptions. This led to disequilibrium when predictions based on their prior beliefs are contradicted and provided the opportunity to construct more appropriate concepts. The designed student-centered instruction allowed the students to have enough time to identify and express their pre-conceptions, examine their usefulness and apply the new concepts and ideas in a context familiar to them. As an illustration, in the lesson on characteristics of acids and bases, after students had constructed the concept of characteristic of acid, base and neutral substances, they had to inquiry and plan an investigation by themselves to examine whether some materials they collected around home could be considered acid, base or neutral. Results of this study showed that most of students (81%) felt very confident in dealing with experimental activity, such as: how to handle a solution properly; to make an accurate observation; to follow their plan and to use the equipments and chemicals appropriately. Students’ prior knowledge and their science process skills each made a significant contribution to their understanding of acid and base concepts. According to Lawson (2001), learning new concepts is not a purely abstract process. Rather, concept acquisition depends upon one’s ability to generate and test ideas or hypotheses and reject those that lead to contradictions. Thus, concept learning can be characterized as ‘constructive’, while new conceptual knowledge depends upon skill in generating and testing ideas. As one gains skill in generating and testing hypotheses, concept constructions become easier. Futhermore Ausubel (1968) claimed, students learned meaningfully by constructing new knowledge on the basis of what they already know. Thus, students existing conceptions have great influence on their further learning. Student outcomes might be improved by creating classroom environments found empirically to be conducive to learning (Fraser, 1994). The result of this present study supports this view.
In the traditional group, however, a concept or a group of related concepts was verbally introduced and explicated in the lecture and/or confirmed in the laboratory activities. Thus, students in the traditional group mainly focused on concepts related to the subject that require less conceptual restructuring.
Possible reasons for the gain score difference between the Japanese and Indonesian students might include the difficulty in communication for the lesson for Japanese students. Chemistry lesson in English was the first experience for Japanese SSH students grade 10. Students should learn English as well as the chemistry content of acids and bases. They had to understand their worksheet in English and do presentation in English. All teaching aid and materials were prepared and delivered to students in English. The students came from various background and had an average socioeconomic status and achievement level compared to other schools within Japan. Eventhough many students (37%) concerned about their English, almost all of them (97%) enjoyed the acids and bases lessons. This was a good aspect to increase students’ motivation and attitudes towards teaching and learning of chemistry. Conversely, for Indonesian students, the acids and bases lessons were delivered in their own language, Indonesian. So, Indonesian students did not have difficulty in communication.
From the results of this study, we concludes that:
1. Designed student-centered instruction based on constructivist, hands-on inquiry and context-based approaches is effective in increasing Indonesian students’ learning achievement. This study indicates that treatment group significantly outperformed the traditional group in understanding the acids and bases concepts.
2. Most of the Indonesian students (97%) in the treatment goup enjoyed working with hands-on activities. They were actively involved and very interested in the activities. They also felt their understandings of the concepts have improved. Students reasoned that through practical activity (39% of students) or this teaching method (41% of students), the concepts were easily understood. Futhermore, some students said that this teaching method was interesting, different with ordinary teaching method and made students more active. They enjoyed because the activity related to their daily lives so that the concepts studied were relevant and meaningful for them. This was supported by some students who chose the identification of daily life materials as acid, base or neutral as the most important concept they had learned. Most of students (81%) felt very confident in dealing with experimental activity.
3. Designed student-centered instruction based on constructivist, hands-on inquiry and context-based approaches is effective in increasing Japanese students’ learning achievement. Japanese students achieved a medium gain score from implementation of designed student-centered instruction. Almost all Japanese students (97%) enjoyed the lessons of acids and bases and most of them (80%) felt that their understandings of the concepts have improved. Some of them found that English as a barrier of their learning but they were getting confident with English.
IMPLICATIONS FOR TEACHING AND LEARNING CHEMISTRY
This student-centered instruction designed using the principles of constructivist, inquiry and context-based approaches may be of particular value to the prospective and inservice science/chemistry teachers, especially in Indonesia. Efforts to increase present & future science teachers’ attitudes toward using inquiry as suggested by the new 2006 curriculum are of particular importance in that they may result in effective science instruction. Although the essencee of inquiry teaching is not always easy to grasp and implementation has proven difficult (Deboer, 2006), the inquiry-based pedagogy designed in this study, underpinned by constructivist and context-based approaches designed in this study has proven its potential to enhance student learning and to motivate the students. Prospective & preservice teachers should understand the variety of ways that inquiry teaching can be used and the range of meanings it can have. This should aid educators in moving towards pedagogies that are effective and motivate students, and that deepen their intellectual engagement with scientific ideas and that give them a better sense of what science is.
For Japanese side, this designed student-centered instruction could be implemented and it might be appropriate for Super Science High School students. Since grade 10 SSH students were benefited from the teaching and learning process in this study, such as: increase students’ achievement, motivate students to engage in the classroom activities and increase their self-confident and skills in English.
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MASYARAKAT MADANI TANTANGAN DAN PELUANG

MASYARAKAT MADANI TANTANGAN DAN PELUANG

MAKALAH
Untuk memenuhi tugas matakuliah
Pendidikan Agama Islam
Yang dibina oleh Ibu Lilik Nur Kholidah
Oleh
Kelompok 3
1. Aan Karuniawan P (100331404567)
2. Ardhi Wiyogo (100331404573)
3. Hasby Alvy Asydiq (100331404586)
4. Yudhistira (100331406389)





JURUSAN KIMIA
FAKULTAS MATEMATIKA DAN ILMU PENGETAHUAN ALAM
UNIVERSITAS NEGERI MALANG
TAHUN 2011

DAFTAR ISI


Halaman Judul i
Daftar Isi ii
BAB I PENDAHULUAN
1.1. Latar Belakang 1
1.2. Topik Bahasan 1-2
1.3. Tujuan Penulisan 2
BAB II PEMBAHASAN
2.1. Defini Masyarakat Madani, Tantangan, dan Peluang 3
2.2. Karakteristik Masyarakat Madani 3-4
2.3. Konsep Masyarakat Madani yang Diterapkan Oleh Nabi Muhammad saw 4-5
2.4. Bentuk Masyarakat Madani di Negara Indonesia dan Negara-Negara Maju 5-7
2.5. Tantangan dan Peluang Dalam Mewujudkan Masyarakt Madani di Indonesia 7-8
2.6. Kendala Dalam Mewujudkan Masyarakat Madani di Indonesia 8
BAB III PENUTUP
3.1. Kesimpulan 9
3.2. Saran 10
DAFTAR PUSTAKA 11





BAB I
PENDAHULUAN

3.1 LATAR BELAKANG
Dewasa ini, istilah masyarakat madani semakin sering dibicarakan. Mula-mula terbatas di kalangan intelektual, misalnya Nurcholish Madjid, Emil Salim, dan Amien Rais. Tetapi perkembangannya menunjukkan istilah masyarakat madani juga disebut-sebut oleh tokoh-tokoh pemerintahan dan politik, misalnya mantan Presiden B.J. habibie, Wiranto, Soesilo bambang Yudoyono dan masih banyak lagi.
Terlahirnya istilah masyarakat madani di Indonesia adalah bermula dari gagasan Dato Anwar Ibrahim, ketika itu tengah menjabat sebagai Menteri keuangan dan Asisten Perdana Menteri Malaysia, ke Indonesia membawa “istilah masyarakat madani” sebagai terjemahan “civil society”. Istilah masyarakat madani pun sebenarnya sangatlah baru, hasil pemikiran Prof. Naquib al-Attas seorang filosof kontemporer dari negeri jiran Malaysia dalam studinya baru-baru ini. Kemudian mendapat legitimasi dari beberapa pakar di Indonesia termasuk seorang Nurcholish Madjid yang telah melakukan rekonstruksi terhadap masyarakat madani dalam sejarah islam pada artikelnya “Menuju Masyarakat Madani”. Sehingga masyarakat madani dalam artian negara menjadi suatu cita-cita bagi negara Indonesia, meskipun sebenarnya pada wilayah-wilayah tertentu, pada tingkat masyarakat kecil, kehidupan yang menyangkut prinsip pokok dari masyarakat madani sudah ada. Sebagai bangsa yang pluralis dan majemuk, model masyarakat madani merupakan tipe ideal suatu mayarakat Indonesia demi terciptanya integritas sosial bahkan integritas nasional.
Sesuai dengan yang dijelaskan di atas, maka penulis mengambil topik yaitu peluang dan tantangan dalam menuju masyarakat madani (civil society), dengan judul “Masyarakat Madani Tantangan dan Peluang”.

3.2 TOPIK BAHASAN
1. Apa yang dimaksud dengan masyarakat madani, tantangan dan peluang ?
2. Bagaiamana karaktesristik masyarakat madani ?
3. Bagaimana konsep masyarakat madani yang diterapkan oleh Nabi Muhammad saw ?
4. Bagaimanakah bentuk masyarakat madani di Negara Indonesia dan Negara maju ?
5. Apa saja tantangan dan peluang dalam mewujudkan masyarakt madani di Indonesia ?
6. Apa saja kendala dalam mewujudkan masyarakat madani di Indonesia ?

3.3 TUJUAN
1. Mengetahui apa yang dimaksud dengan masyarakat madani, tantangan dan peluang.
2. Mengetahui karaktesristik masyarakat madani.
3. Mengetahui konsep masyarakat madani yang diterapkan oleh Nabi Muhammad saw.
4. Menhetahui bentuk masyarakat madani di ocial Indonesia dan negara-negara maju.
5. Mengetahui tantangan dan peluang dalam mewujudkan masyarakt madani di Indonesia.
6. Mengetahui kendala dalam mewujudkan masyarakat madani di Indonesia.

BAB II
PEMBAHASAN

2.1 Defini Masyarakat Madani, Tantangan, dan Peluang
Masyarakat madani sebagai terjemahan dari civil society diperkenalkan pertama kali oleh Anwar Ibrahim (ketika itu Menteri Keuangan dan Timbalan Perdana Menteri Malaysia) dalam ceramah Simposium Nasional dalam rangka Forum Ilmiah pada Festival Istiqlal, 26 September 1995. Istilah itu diterjemahkan dari bahasa Arab mujtamaâ madani, yang diperkenalkan oleh Prof. Naquib Attas, seorang ahli sejarah dan peradaban Islam dari Malaysia, Kata “madani” berarti civil atau civilized (beradab). Sehingga, secara ontologis, masyarakat madani adalah masyarakat yang demokratis yang bertujuan untuk meredam berbagai tuntutan reformasi baik dari dalam maupun luar negeri.
Masyarakat madani adalah sebuah masyarakat demokratis dimana para anggotanya menyadari akan hak-hak dan kewajibannya dalam menyuarakan pendapat dan mewujudkan kepentingan-kepentingannya; dimana pemerintahannya memberikan peluang yang seluas-luasnya bagi kreatifitas warga ocial untuk mewujudkan program-program pembangunan di wilayahnya.
Tantangan mempunyai arti hal atau objek yg menggugah tekad untuk meningkatkan kemampuan mengatasi masalah; rangsangan (untuk bekerja lebih giat dsb).
Peluang mempunyai arti kata ruang gerak, baik yg konkret maupun yg abstrak, yg memberikan kemungkinan bagi suatu kegiatan untuk memanfaatkannya dl usaha mencapai tujuan; kesempatan.
2.2 Karakteristik Masyarakat Madani
Ada beberapa karakteristik dari masyarakat madani, antara lain :
a. Free public sphere (ruang social yang bebas), yaitu masyarakat memiliki akses penuh terhadap setiap kegiatan social, mereka berhak melakukan kegiatan secara merdeka dalam menyampaikan pendapat, berserikat, berkumpul, serta mempublikasikan informasikan kepada social.
b. Demokratisasi, yaitu proses untuk menerapkan prinsip-prinsip demokrasi sehingga muwujudkan masyarakat yang demokratis. Untuk menumbuhkan demokratisasi dibutuhkan kesiapan anggota masyarakat berupa kesadaran pribadi, kesetaraan, dan kemandirian serta kemampuan untuk berperilaku demokratis kepada orang lain dan menerima perlakuan demokratis dari orang lain. Demokratisasi dapat terwujud melalui penegakkan pilar-pilar demokrasi yang meliputi : (1) Lembaga Swadaya Masyarakat (LSM), (2) Pers yang bebas, (3) Supremasi hukum, (4) Perguruan Tinggi, (5) Partai politik
c. Toleransi, yaitu kesediaan individu untuk menerima pandangan-pandangan politik dan sikap social yang berbeda dalam masyarakat, sikap saling menghargai dan menghormati pendapat serta aktivitas yang dilakukan oleh orang/kelompok lain.
d. Pluralisme, yaitu sikap mengakui dan menerima kenyataan mayarakat yang majemuk disertai dengan sikap tulus, bahwa kemajemukan sebagai nilai positif dan merupakan rahmat dari Tuhan Yang Maha Kuasa.
e. Keadilan social (social justice), yaitu keseimbangan dan pembagian yang proporsiaonal antara hak dan kewajiban, serta tanggung jawab individu terhadap lingkungannya.
f. Partisipasi social, yaitu partisipasi masyarakat yang benar-benar bersih dari rekayasa, intimidasi, ataupun intervensi penguasa/pihak lain, sehingga masyarakat memiliki kedewasaan dan kemandirian berpolitik yang bertanggungjawab.
g. Supremasi social, yaitu upaya untuk memberikan jaminan terciptanya keadilan. Keadilan harus diposisikan secara netral, artinya setiap orang memiliki kedudukan dan perlakuan social yang sama tanpa kecuali.
2.3 Konsep Masyarakat Madani yang Diterapkan Oleh Nabi Muhammad saw
Umat Islam telah memperkenalkan konsep peradaban masyarakat madani atau civil society pada masa Nabi Muhammad saw. Rosullullah s.a.w sendiri yang memberikan teladan social pembentukan masyarakat peradaban tersebut. Setelah perjuangan di kota Makkah tidak menunjukkan hasil yang berarti, Allah telah menunjuk sebuah kota kecil, yang selanjutnya kita kenal dengan Madinah untuk dijadikan basis perjuangan menuju masyarakat peradaban yang dicita-citakan. Di kota itu Nabi meletakan dasar-dasar masyarakat madani yakni kebebasan. Untuk meraih kebebasan, khususnya di bidang agama, ekonomi, social dan politik, Nabi diijinkan untuk memperkuat diri dengan membangun kekuatan bersenjata untuk melawan musuh peradaban. Hasil dari proses itu dalam sepuluh tahun, beliau berhasil membangun sebuah tatanan masyarakat yang berkeadilan, terbuka dan demokratis dengan dilandasi ketaqwaan dan ketaatan kepada ajaran Islam. Salah satu yang utama dalam tatanan masyarakat ini adalah pada penekanan pola komunikasi yang menyandarkan diri pada konsep egalitarian pada tataran horizontal dan konsep ketaqwaan pada tatara vertical . Nurcholis Madjid (1999:167-168) menyebut dengan semangat rabbaniyah atau ribbiyah sebagai landasan vertical, sedangkan semangat insyanyah atau basyariah yang melandasi komunikasi horizontal.
Sistem sosial madani ala Nabi s.a.w memiliki ciri unggul, yakni kesetaraan, istiqomah, mengutamakan partisipasi, dan demokratisasi. Esensi ciri unggul tetap relavan dalam konteks waktu dan tempat berbeda, sehingga pada dasarnya prinsip itu layak diterapkan apalagi di Indonesia yang mayoritas berpenduduk muslim tanpa mengusik kepentingan dan keyakinan kelompok minoritas. Mengenai hal yang terakhir ini Nabi s.a.w telah memberi cotoh yang tepat, bagaimana sebaiknya memperlakukan kelompok minoritas ini.
2.4 Bentuk Masyarakat Madani di Negara Indonesia dan Negara-Negara Maju
2.4.1 Negara Indonesia
1. Sebelum Merdeka
Di mulai saat munculnya Budi Utomo ( 1908 ), saat kaum priyayi Jawa membentuk asosiasi social.
2. Sesudah Merdeka
Perjuangan Civil Society di Indonesia pada awal pergerakan kebangsaan dipelopori oleh Syarikat Islam (1912) dan dilanjutkan oleh Soeltan Syahrir pada awal kemerdekaan. Jiwa demokrasi Soeltan Syahrir ternyata harus menghadapi kekuatan represif baik dari rezim Orde Lama di bawah pimpinan Soekarno maupun rezim Orde Baru di bawah pimpinan Soeharto.
Bila kita berpaling pada sejarah kota Ternate, maka mozaik kota hampir selalu merupakan pergelaran seni social yang terbentuk dari berbagai rencana ragam perorangan, masyarakat dan kelembagaan. Semua luluh jadi satu. Keterlibatan aktif segenap pihak termasuk penghuni kota akan membuahkan hasil penampilan kota unik, berpribadi dan mengesahkan sesuai visi dan misi kota ini. Penampilan yang di maksudkan tidak sekedar dalam konotasi keindahan fisual belaka, melainkan menyentuh juga kesejahteraan ekonomi dan keselarasan budayanya sehingga menjadikan Ternate sebagai kota budaya menuju Masyarakat Madani yang memiliki jati diri.
2.4.2 Negara-Negara Maju
1. Jepang
Masyarakat Sipil telah menjadi topik panas di Jepang. Dari surat kabar di negara ini, secara berkala melaporkan perkembangan shimin sanka (partisipasi masyarakat) dan borantia katsudo (kegiatan sukarelawan). Ini mencerminkan kepentingan umum, sejumlah tokoh sipil baik di dalam dan di luar negeri telah mulai melakukan penelitian lebih dekat kepada masyarakat sipil di Jepang. Bahkan, masyarakat Jepang merupakan objek menarik untuk kegiatan belajar mengajar. Yang berbeda dari berbagai negara demokrasi di Barat, meskipun konstitusi menjamin kebebasan berserikat, aktivisme populer secara tradisional telah terikat oleh peraturan pemerintah. Aktivisme sangat terikat oleh peraturan pemerintah sehingga kemungkinan besar terhambatnya perkembangan Civil Society.
2. Amerika Serikat
Pemilihan Presiden Amerika Serikat meninggalkan catatan penting bagi proses demokrasi yang berlangsung di Negeri paman Sam. Hampir seluruh lapisan masyarakat dunia dibawa dalam suatu tontonan menarik tentang berlangsungnya demokrasi ala Amerika. Hampir semua media international, nasional maupun lokal menempatkan proses demokrasi di negara adidaya tersebut sebagai head line. Sangat wajar, karena Amerika merupakan Negara yang menjadi mother of democracy.
Demikian halnya, rakyat Amerika mampu mempertontonkan kedewasaan mereka dalam berpolitik, dimana semua proses demokrasi dapat dilewati secara lebih bermakna tanpa harus diwarnai dengan konflik dan bentrokan pendukung antar kandidat. Masyarakat Amerika telah memberikan pelajaran bagi semua negara yang ingin mewujudkan demokrasi, bahwa demokrasi harus dibangun dengan cara-cara yang elegan dan beradab. Demokrasi tidak akan tumbuh dan berkembang dalam masyarakat, yang karena perbedaan pandangan politik ataupun tidak puas dengan proses politik kemudian mengekspresikan dengan cara-cara kekerasan dan anarkhis. Di sinilah letaknya kekuatan Civil Society dalam masyarakat Amerika yang mampu melihat dan menyikapi proses politik secara lebih cerdas dan bermartabat. Sehingga Barack Obama mampu menjadi jawaban terhadap pluralitas dan individualitas rakyat Amerika, yang selama ini menjadi hambatan dalam terbentuknya Civil Society.

2.5 Tantangan dan Peluang Dalam Mewujudkan Masyarakt Madani di Indonesia
2.5.1 Tantangan
Ada beberapa tantangan dalam mewujudkan masyarakat madani di indonesia, antara lain :
a) Masih rendahnya minat partisipasi warga masyarakat terhadap kehidupan politik Indonesia dan kurangnya rasa nasionalisme yang ditandai dengan kurang rasa peduli masyarakat dengan masalah-masalah yang dihadapi social Indonesia sehingga sulit untuk menerapkan masyarakat yang memiliki akses penuh dalam kegiatan social, melakukan kegiatan secara merdeka dalam menyampaikan pendapat, berserikat dan berkumpul serta menyampaikan informasi kepada social.
b) Masih kurangnya sikap toleransi baik dalam kehidupan bermasyarakat maupun beragama.
c) masih kurangnya kesadaran Individu dalam keseimbangan dan pembagian yang proporsional antara hak dan kewajiban.
2.5.2 Peluang
Ada beberapa peluang dalam mewujudkan masyarakat madani di indonesia, antara lain :
a) Budaya demokrasi, yang mulai tumbuh pada saat masa reformasi.
b) Pewujudkan keadilan sosial bagi seluruh rakyat Indonesia.
2.6 Kendala Dalam Mewujudkan Masyarakat Madani di Indonesia
Ada beberapa yang menjadi kendala dalam mewujudkan masyarakat madani di indonesia, antara lain :
a) Kualitas SDM yang belum memadai karena pendidikan yang belum merata
b) Masih rendahnya pendidikan politik masyarakat
c) Kondisi ekonomi nasional yang belum stabil pasca krisis moneter
d) Tingginya angkatan kerja yang belum terserap karena lapangan kerja yang terbatas
e) Pemutusan Hubungan Kerja (PHK) sepihak dalam jumlah yang besar
f) Kondisi social politik yang belum pulih pasca reformasi.

BAB III
PENUTUP
3.1 Kesimpulan
Berdasarkan pembahasan di atas dapat disimpulkan bahwa masyarakat madani pada prinsipnya yaitu: free public sphere (tuang publik yang bebas), demokratisasi, toleransi, pluralisme, keadilan sosial (social justice), partisipasi sosial, dan suspensi hukum. Perbedaan yang tampak jelas adalah civil society tidak mengaitkan prinsip tatanannya pada agama tertentu. Dengan demokrasi, rakyat boleh berharap bahwa masa depannya ditentukan dari, oleh dan untuk rakyat. Pengertian pemberdayaan masyarakat madani perlu terus ditingkatkan dan mendapat perhatian sungguh-sungguh dari setiap penyelenggara negara. Bahkan untuk menjamin peradaban bangsa di masa depan, wilayah (domain) negara (state), masyarakat (civil society) dan pasar (market) itu sama-sama harus dikembangkan keberdayaanya dalam hubungan yang seimbang.
Sistem social madani ala Nabi s.a.w merupakan teladan yang baik dalam mewujudkan masyarakat madani yang memiliki ciri unggul, yakni kesetaraan, istiqomah, mengutamakan partisipasi, dan demokratisasi. Esensi ciri unggul tetap relavan dalam konteks waktu dan tempat berbeda, sehingga pada dasarnya prinsip itu layak diterapkan apalagi di Indonesia yang mayoritas berpenduduk muslim tanpa mengusik kepentingan dan keyakinan kelompok minoritas.
Negara Indonesia masih sangat tertinggal jauh dengan negara–negara lain seperti Jepang dan Amerika Serikat dalam sistem demokrasi. Titik beratnyaialah demokrasi yang ada di negara maju tersebut dibangun dengan cara-cara yang elegan dan beradab. Demokrasi tidak akan tumbuh dan berkembang dalam masyarakat, yang karena perbedaan pandangan politik ataupun tidak puas dengan proses politik kemudian mengekspresikan dengan cara-cara kekerasan dan anarkhis. Di sinilah letaknya kekuatan Civil Society dalam masyarakat Amerika yang mampu melihat dan menyikapi proses politik secara lebih cerdas dan bermartabat.


3.2 Saran
Masyarakat madani kiranya perlu terus dikembangkan sejalan dengan demokratisasi dalam kehidupan bermasyarakat, berbangsa dan bernegara.Salah satu cara untuk mewujudkan itu adalah dengan demokratisasi pendidikan, yang berguna untuk mempersiapkan anak bangsa agar terbiasa bebas berbicara dan mengeluarkan pendapat secara bertanggung jawab dan turut bertanggung jawab ,serta terbiasa mendengar dengan baik dan menghargai pendapat orang lain, menumbuhkan keberanian moral yang tinggi, terbiasa bergaul dengan sesama, ikut merasa memiliki, sama-sama merasakan suka dan duka dengan masyarakatnya, dan mempelajari kehidupan bermasyarakat. Dengan kata lain, saling menjaga keseimbangan untuk menegakkan hukum yang sehat dan demokrasi. Baik menjadi anggota masyarakat madani maupun perangkat negara hendaknya dapat mewujudkan negara yang menjunjung tinggi demokrasi, yang dapat membentuk Civil Society yang utuh, dan tidak hanya menjadi mimpi bangsa ini.




DAFTAR PUSTAKA

Ahira, Anne, “Budaya Demokrasi Menuju Masyarakat Madani”, http://www.anneahira.com, diakses tanggal 22 maret 2011
Craig Calhoun, “Social Theory of the Politics of Identity”, Blackwell Publihers, USA,1994.
Hanifah, mutia.2009.Tantangan dan Hambatan Penerapan Masyarakat Madani di Indonesia.
http://www.artikata.com, diakses 22 maret 2011
Madjid, Nurcholish, “Menuju Masyarakat Madani”, http://www.fajar.co.id.diakses tanggal 22 maret 2011
Nezar Patria, dan Andi Arief, “Antonio Gramci: Negara dan Hegemoni”, Pustaka Pelajar 1999.
Neera Chandoke, “State and Civil Society: Exploration in Political Theory”. New Delhi dan London: Sage Publication,1955.
Nico Schulte Nordholt, “Menyokong Civil Society dalam era Kegelisahan”, dalam Mengenang Y.B. Mangunwijaya, Sindhunata (eds.).Kanisius, 1999.

EKOSISTEM DAN KOMPONEN PENYUSUNNYA



LAPORAN

Untuk memenuhi tugas matakuliah
Praktikum Biologi Umum
Yang dibina oleh Ibu Balqis Spd. Mpd


oleh

YUDHISTIRA
100331406389
















UNIVERSITAS NEGERI MALANG
FAKULTAS MATEMATIKA DAN ILMU PENGETAHUAN ALAM
JURUSAN KIMIA
Oktober 2010


A. Topik :
Ekosistem Dan Penyusunnya

B. Tujuan :
- Mengidentifikasi komponen biotic dan abiotik ekosistem
- Mengukur kondisi beberapa faktor fisiko-kimia di suatu ekosistem
- Menghitung atau memperkirakan jumlah atau besar populasi komponen biotic di suatu ekosistem
- Memperkirakan/menginterpretasikan interaksi antara komponen biotic di suatu ekosistem.
- Menjelaskan secara tepat pengertian ekosistem.

C. Alat dan Bahan
Alat :
1. Roll meter
2. Temperature tanah
3. Termohigrometer
4. Patok bamboo
5. Kantung plastic
6. Loupe
7. Ph meter
8. Tali raffia
9. Kertas label

Bahan :
1. Sebidang tanah 4x4 m


















D. Cara Kerja

1. Dipilih atau ditentukan suatu lokasi yang akan dijadikan tempat untuk mengamati, menghitung, dan mengukur beberapa komponen ekosistem.
2. Diambil sebidang lokasi sebagai contoh dari suatu ekosistem yang akan dijadikan bahan pengamatan, 4x4 m2 dan dibagi menjadi 4 bagian.
3. Diamati dan diidentifikasi semua komponen ekosistem yang ada. Untuk komponen biotik diidentifikasi jenisnya dan diperkirakan jumlahnya. Jika belum diketahui nama hewan dan tumbuhan yang pasti dapat menggunakan kode dan diambil contohnya, diberi label atau kode untuk diidentifikasi. Untuk komponen abiotik diukur pH, kelembaban, dan suhu.
4. Dilakukan pengamatan secermat mungkin

E. Hasil Pengamatan dan Hasil Analisa Data

Bidang Spesies Jumlah Identifikasi Gambar
Plot 1 Hewan
1. Semut hitam besar




2. Semut hitam kecil




3. Semut merah besar




4. Semut merah kecil






5. Laba-laba





6. Lalat
(Drosophilla )
12





6





7





12







1





1 Berwarna hitam, berkaki 6, mempunyai antena, ukurannya besar



Berwarna hitam, berkaki 6, mempunyai antena, ukurannya kecil



Berwarna merah, berkaki 6, mempunyai antena, ukurannya besar



Berwarna merah, berkaki 6, mempunyai antena, ukurannya besar





Berkaki 8, memiliki bulu halus




Bersayap, mempunyai antena, berkaki 6














Tumbuhan
1. Rumput gajah





2. Rumput teki
( Cyperus compressus )



3. Pepaya


4. Sendok
1500





90





5


2
Menjalar, daun membujur





Daun berjajar peda pangkal batang, daun membujur.



Daun menjari, akar serabut

Daun bulat, batang memanjang


Plot 2 Hewan
1. Semut hitam besar


2. Semut hitam kecil




3. Semut merah besar





4. Semut merah kecil




5. Cacing






6. Jangkrik




7. Belalang
50


90






2






8





2






2




1 Berwarna hitam, berkaki 6, mempunyai antena, ukurannya besar

Berwarna hitam, berkaki 6, mempunyai antena, ukurannya kecil



Berwarna merah, berkaki 6, mempunyai antena, ukurannya besar




Berwarna merah, berkaki 6, mempunyai antena, ukurannya besar



Tubuhnya panjang, kecil, hewan melata





Bersayap, mempunyai antena, berkaki 6



Berkaki enam, mempunyai antena, ukurannya besar















Tumbuhan

1. Rumput gajah





2. Rumput teki
( Cyperus compressus )




3. Rumput knop (Cyperus killyngia endla)

1000





80





17

Menjalar, daun membujur





Daun berjejal pada pangkal batang, daun membujur.



Daun berjejer pada pangkal batang, bunga tersusun dalam bulir











Plot 3 Hewan
1. Semut hitam besar



2. Semut hitam kecil



3. Lalat




4. Kupu-kupu




5. Kumbang



6. Laba-laba




7. Belalang





8. Jangkrik




9. Lalat buah





10. Nyamuk

8




12




2




1




1



3




4





20




1





5 Berwarna hitam, berkaki 6, mempunyai antena, ukurannya besar


Berwarna hitam, berkaki 6, mempunyai antena, ukurannya kecil


Bersayap, mempunyai antena, berkaki 6



Bersayap, berkaki enam, berukuran besar



Bentuk mulut tipe penusuk, berkaki enam


Berkaki 8, memiliki bulu halus



Bersayap, mempunyai antena, berkaki 6




Berkaki enam, mempunyai antena, ukurannya besar


Bersayap, mempunyai antena, berkaki 6




Mulut bertipe penusuk, bersayap, berkaki enam























Tumbuhan
1. Rumput gajah






2. Rumput teki
( Cyperus compressus )



3. Pepaya


4. Rumput belulang (Eleusine indica)

5. Rumput telor ikan (Cyrtococcum acrescens)
1800






100




28


23




13

Menjalar, daun membujur






Daun berjejal pada batang, daun membujur.



Daun menjari, akar serabut

Daun panjang dan membujur



Daun berjejal pada pangkal batang






Plot 4 Hewan
1. Semut hitam besar



2. Semut hitam kecil



3. Semut merah besar



4. Semut merah kecil



5. Laba-laba




6. Belalang 10




6




3




5




2




9 Berwarna hitam, berkaki 6, mempunyai antena, ukurannya besar


Berwarna hitam, berkaki 6, mempunyai antena, ukurannya kecil


Berwarna merah, berkaki 6, mempunyai antena, ukurannya besar


Berwarna merah, berkaki 6, mempunyai antena, ukurannya besar


Berkaki 8, memiliki bulu halus



Berkaki enam, mempunyai antena, ukurannya besar











Tumbuhan
1. Rumput gajah








2. Rumput teki
( Cyperus compressus )



3. Pepaya 1600








25




18 Menjalar, daun membujur








Daun berjejal pada pangkal batang, daun membujur.


Daun menjari, akar serabut









Hasil Pengamatan



Analisa Data
Pada suatu komponen ekosistem terdapat komponen biotik dan abiotik. Komponen biotik berupa tumbuhan, hewan, termasuk manusia, dan mikroorganisme. Komponen abiotik berupa tanah, air, udara, cahaya, dan kondisi fisiko-kimia tanah, air, dan udara ( seperti suhu, pH, kelembaban, kadar gas tertentu).
Dari pengamatan didapatkan :
1. Kelembaban pada termohigrometer menunjukkan angka 33oC
2. pH meter menunjukkan angka 6,8
3. Termometer tanah menunjukkan angka 250C/79oF
Pada setiap plot memiliki komponen ekosistem yang hampir sama dikarenakan komponen abiotik yang dimiliki sama. Jadi kelembapan, pH, dan suhu tanah mempengaruhi komponen biotik didalamnya.










F. Kesimpulan

Ekosistem adalah hubungan antara komponen biotik dan abiotik yang saling membentuk interaksi antara satu dengan yang lain dan membentuk keseimbangan. Dalam ekosistem terdapat komponen biotik dan abiotik. Komponen biotik berupa tumbuhan, hewan, termasuk manusia, dan mikroorganisme. Komponen abiotik berupa tanah, air, udara, cahaya, dan kondisi fisiko-kimia tanah, air, dan udara ( seperti suhu, pH, kelembaban, kadar gas tertentu).



G. Daftar Pustaka

Yakup & Sukman Yenelis, Hj. 2002. Gulma dan Teknik Pengendaliannya. Jakarta: PT Raja Grafindo Persada
Rukmana Rahmat, Ir.H & Saputra Uu Sugandi, B.Sc. 2003. Gulma dan Teknik Pengendalian. Yogyakarta: Kanisius