ANALISIS KESUBURAN PERAIRAN BERDASARKAN BAHAN ORGANIK TOTAL, NITRAT, FOSFAT DAN KLOROFIL-a DI SUNGAI JAJAR KABUPATEN DEMAK - Wijayanto, Adhitya; Purnomo, Pujiono Wahyu; Suryanti, - (Management of Aquatic Resources Journal (MAQUARES), 2015)
Perkembangan pemanfaatan lahan pada kawasan dan lingkungan perairan sungai dapat memberikan pengaruh terhadap penurunan kualitas perairan yang dicirikan dengan penurunan kesuburan perairan. Kesuburan suatu perairan dipengaruhi oleh sediaan materi bahan organik, unsur hara (nitrat dan fosfat), dan klorofil-a, serta variabel fisika kimia perairan. Penelitian dilakukan pada bulan Desember 2014 – Januari 2015 di Sungai Jajar, yang bertujuan untuk mengetahui kandungan Bahan Organik, NO3, PO4, dan klorofil-a di beberapa wilayah Sungai Jajar dan mengetahui keterkaitan antara bahan organik total dengan nitrat dan fosfat serta nitrat dan fosfat dengan klorofil-a untuk melihat tingkat kesuburannya. Metode  yang digunakan adalah metode deskriptif dengan teknik purposive random sampling. Hasil penelitian menunjukkan bahwa kesuburan perairan berdasarkan kandungan nitrat tergolong dalam kesuburan rendah (oligotrofik) hingga sedang (mesotrofik). Berdasarkan kandungan fosfatnya tergolong dalam kategori subur (eutrofik). Berdasarkan kandungan klorofil-a kesuburan perairan Sungai Jajar tergolong kesuburan yang rendah (oligotrofik). Keterkaitan antara klorofil-a dengan nitrat dan fosfat di perairan Sungai Jajar secara parsial lebih kuat hubungan antara fosfat terhadap klorofil-a. Nitrat tidak menunjukkan hubungan yang kuat terhadap klorofil-a. Berdasarkan analisa statistik regresi linier berganda, secara keseluruhan nitrat dan fosfat mempunyai korelasi dan hubungan linier positif atau memberikan pengaruh terhadap kandungan klorofil-a. As the development of land use in the area and the river water environment can influence mainly the alleged decline of the quality of water that is characterized by a decrease in aquatic fertility. The fertility of a aquatic area is also affected by the total organic matter, hara unsure (nitrate and phosphate), and chlorophyll-a, as well as the variable of aquatic physics and chemist. This research was done on December 2014-January 2015 in River Jajar, which is aimed to identify the relationship between Total Organis Matter NO3, PO4, and Chlorophyll-a in some areas approaching flow Jajar River estuary and determine the link between nitrate and phosphate with a total organic matter and chlorophyll -a with nitrate and phosphate to see the level of fertility.. This research used the descriptive method  using purposive sampling. The results showed that the fertility waters by nitrate content belonging to the low fertility (oligotrophic) to moderate (mesotrophic). Based on the phosphate content of classified in the category fertile (eutrophic). Based on the content of chlorophyll-a fertility Jajar river waters classified as low fertility (oligotrophic).The linkage between chlorophyll-a by nitrate and phosphate in the waters of the Jajar River partially stronger relationship between phosphate to chlorophyll-a. Nitrates did not showed a strong relationship to the chlorophyll-a. Based on statistical analysis of multiple linear regression, together nitrates and phosphates have a positive correlation and linear relationship or have influence on the content of chlorophyll-a.