KUALITI AIR SUNGAI BERDASARKAN ANALISIS KIMIA DAN KEPELBAGAIAN ALGA NOR AZMAN BIN KASAN UNIVERSITI TEKNOLOGI MALAYSIA

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KUALITI AIR SUNGAI BERDASARKAN ANALISIS KIMIA DAN KEPELBAGAIAN ALGA NOR AZMAN BIN KASAN UNIVERSITI TEKNOLOGI MALAYSIA

KUALITI AIR SUNGAI BERDASARKAN ANALISIS KIMIA DAN KEPELBAGAIAN ALGA NOR AZMAN BIN KASAN Tesis ini dikemukakan sebagai memenuhi syarat penganugerahan ijazah Sarjana Kejuruteraan (Alam Sekitar) Fakulti Kejuruteraan Awam Universiti Teknologi Malaysia JUN 2006

iii Dedikasi Khas buat bonda yang disayangi, Pengorbananmu adalah pembakar semangatku untuk terus berjuang, Buat abang-abang dan adik yang diingati, Kejayaanku bakal menebus maruah keluarga, Buat teman-teman seperjuangan, Kalian mempunyai keistimewaan tersendiri, Terima kasih atas segalanya, dan, Teristimewa buat Baiyurah Bte Mohamed Esa, Segala dorongan dan semangat darimu amatlah kuhargai, Semoga hubungan yang terjalin direstui Allah S.W.T dan kekal buat selamanya.

iv PENGHARGAAN Alhamdullilah, setinggi-tinggi kesyukuran dipanjatkan ke hadrat Allah S.W.T kerana dengan limpah rahmat dan kurnia-nya dapatlah saya menghasilkan tesis bagi program ijazah Sarjana Kejuruteraan (Alam Sekitar). Ucapan jutaan terima kasih ditujukan khas buat kedua-dua pembimbing saya iaitu Dr. Johan Bin Sohaili dan Prof Madya Dr. Zaharah Bte Ibrahim di atas segala tunjuk ajar, nasihat serta komitmen tinggi yang telah diberikan. Ucapan penghargaan juga ditujukan kepada pihak Research Management Centre (RMC), Universiti Teknologi Malaysia yang telah membiayai kajian ini melalui no. vot 75081. Tidak dilupakan kepada Prof. Dr. Phang Siew Moi dan Dr. Chu Wan Loy yang merupakan pakar terhadap pengenalpastian spesis-spesis alga di Makmal Institut Sains Biologi, Universiti Malaya, Kuala Lumpur. Jutaan penghargaan ditujukan kepada warga JPS, Pontian terutamanya Ir. Azman Bin Yahya, Ir. Zaiton Bte Abdul Hamid dan En. Satar Bin Jofri yang telah membekalkan data taburan hujan di sepanjang kawasan kajian. Penghargaan juga ditujukan kepada juruteknik-juruteknik yang bertugas di Makmal JKAS, FKA yang telah membantu saya ketika menjalankan persampelan serta analisis di makmal terutamanya En. Azlan Abd Aziz, En. Zulkurnain, En. Yusoff, En. Ramlee Ismail, En. Ramli Aris dan En. Muzafar Nor. Tidak dilupakan kepada rakan-rakan seperjuangan yang banyak membantu serta mendorong perjalanan penyelidikan ini. Terima kasih atas segalanya. Akhir sekali, ucapan terima kasih dan setinggi-tinggi penghargaan kepada semua ahli keluarga serta semua yang terlibat secara langsung atau tidak langsung dalam menjayakan projek sarjana ini. Semoga jasa-jasa kalian mendapat keberkatan daripada Ilahi.

v ABSTRAK Sungai Pontian Kecil digunakan oleh penduduk di sekitar Daerah Pontian untuk menjalankan aktiviti harian mereka seperti sumber bekalan air pengairan, perikanan dan rekreasi. Kajian terhadap Sungai Pontian Kecil dijalankan pada bulan tidak hujan dan bulan hujan. Tahap pencemaran air ditentukan berdasarkan Indeks Kualiti Air (WQI) dan Indeks Diversiti Shannon-Weiner (H ). Perkaitan antara kedua-dua indeks tersebut ditentunilaikan. Aktiviti gunatanah yang menyumbang terhadap kemerosotan kualiti air sungai termasuklah pembuangan air sisa kumbahan, aktiviti pertanian dan aktiviti penempatan di sepanjang koridor sungai. Analisis kimia air sungai dilakukan bagi memperoleh nilai WQI. Di samping itu, nilai H diperoleh berdasarkan pengklasifikasian alga. Keputusan mendapati terdapat perkaitan antara WQI dan H di mana kualiti air di hulu adalah Kelas II ketika bulan tidak hujan dengan nilai masing-masing 75 dan 3.08, manakala pada bulan hujan nilai WQI dan H masing-masing adalah 85 dan 2.90, menunjukkan kualiti air bersih pada kedua-dua bulan berkenaan. Sebaliknya, kualiti air di hilir adalah Kelas IV dengan nilai masing-masing 38 dan 1.42 pada bulan tidak hujan, manakala pada bulan hujan nilai masing-masing adalah 35 dan 1.20, menunjukkan pencemaran kualiti air. Kehadiran kelas alga Bacillariophyceae dan Chlorophyceae yang banyak menunjukkan kualiti air yang bersih, manakala kehadiran kelas Euglenophyceae dan Cyanophyceae pula menunjukkan pencemaran. Didapati Navicula sp. adalah spesis alga yang dominan pada kedua-dua bulan tidak hujan dan bulan hujan. Kiraan sel alga di hulu adalah tinggi iaitu masing-masing 8870 sel/ml dan 7828 sel/ml berbanding di hilir dengan jumlah spesis masing-masing adalah 1138 sel/ml dan 353 sel/ml pada kedua-dua bulan. Kesimpulannya, pencemaran kualiti air mempengaruhi populasi alga di dalam sungai di mana populasi alga adalah tinggi pada kualiti air yang bersih.

vi ABSTRACT Sungai Pontian Kecil is used by villagers around Pontian District for their daily activities such as water supply for irrigation, fisheries and recreation. Study on Sungai Pontian Kecil was conducted during non-raining and raining months. The level of water pollution was determined based on Water Quality Index (WQI) and Shannon-Weiner Index (H ). The relationship between both indexes was evaluated. The land use activities that contributed to the decline of water quality of the river include discharge of wastewater, agricultural activities and settlements along the river corridor. Chemical analysis of the river water was used to determine WQI value. Besides that, H value was based on the classification of algae. Results showed that there is a relationship between WQI and H where water quality at the upstream is Class II during non-raining month with 75 and 3.08 respectively, while during raining month the WQI and H were 85 and 2.90 respectively, indicating clean water quality during both months. On the other hands, water quality at the downstream is Class IV with 38 and 1.42 respectively during non-raining month, while 35 and 1.20 respectively during raining month, indicating polluted water quality. The presence of large amount of Bacillariophyceae and Chlorophyceae classes indicated clean water quality, while the presence of Euglenophyceae and Cyanophyceae classes indicated pollution. It was found that Navicula sp. was the dominant algae species during both non-raining and raining months. Algae cell calculation at the upstream was high with 8870 cell/ml and 7828 cell/ml respectively compared to the downstream with 1138 cell/ml and 353 cell/ml respectively during both months. As a conclusion, polluted water quality influences algae populations in the river where algae populations are high at clean water quality.