Hubungan Keanekaragaman Jenis Bivalvia dengan Kadar Timbal (Pb) Air dan Sedimen di Pantai Joko Moersodo Lamongan

Correlation Between Bivalves Species Diversity with Water and Sediment Lead (Pb) Levels at Joko Moersodo Beach Lamongan 

Pantai Joko Moersodo berada di pesisir utara Jawa Timur, tepatnya Kabupaten Lamongan. Pantai Joko Moersodo berdekatan dengan tempat Pangkalan Pendaratan Ikan, permukiman penduduk, dan tambak, serta digunakan sebagai tempat pariwisata, sehingga diduga Pantai Joko Moersodo tercemar logam berat timbal. Bivalvia banyak ditemukan di Pantai Joko Moersodo dan diketahui dapat mengakumulasi logam berat, sehingga digunakan sebagai bioindikator perairan. Tujuan penelitian ini adalah mengidentifikasi dan mendeskripsikan keanekaragaman jenis bivalvia, serta menganalisis hubungan keanekaragaman jenis bivalvia dengan kadar timbal air dan sedimen di Pantai Joko Moersodo. Terdapat 3 stasiun yang terdiri dari tiga sub-stasiun. Pada setiap sub-stasiun ditetapkan plot 5x5 m dan terdapat sub-plot dengan luas 1x1 m sebanyak lima titik. Sampel air diukur dengan parameter fisika-kimia. Pengujian kadar timbal air dan sedimen menggunakan metode Atomic Absorption Spectrophotometry. Data dianalisis dengan uji korelasi Pearson untuk mengetahui hubungan keanekaragaman jenis bivalvia dengan kadar timbal air dan sedimen di Pantai Joko Moersodo. Hasil penelitian menunjukkan bahwa bivalvia yang ditemukan di Pantai Joko Moersodo terdiri dari 7 spesies yang termasuk dalam 6 genus dan 3 famili, indeks keanekaragaman bivalvia termasuk diversitas sedang dengan perairan tercemar sedang, serta hubungan keanekaragaman jenis bivalvia dengan kadar timbal air dan sedimen di Pantai Joko Moersodo menunjukkan hasil yang tidak signifikan. 

Joko Moersodo Beach is on the north coast of East Java, Lamongan Regency to be precise. Joko Moersodo Beach is close to the Fish Landing Base, residential areas, and ponds, and is used as a tourism site, so it is suspected that Joko Moersodo Beach is polluted by the heavy metal lead. Bivalvia are commonly found on Joko Moersodo Beach and are known to accumulate heavy metals, so they are used as aquatic bioindicators. The purpose of this study was to identify and describe the diversity of bivalves, and to analyze the correlation between the diversity of bivalves and the levels of lead in water and sediments at Joko Moersodo Beach. There are 3 stations consisting of three sub-stations. At each sub-station a plot of 5x5 m is determined and there are sub-plots with an area of 1x1 m as many as five points. Water samples were measured with physico-chemical parameters. Testing for lead levels in water and sediments uses the Atomic Absorption Spectrophotometry method. Data were analyzed using the Pearson correlation test to determine the correlation between bivalve species diversity and water and sediment lead content at Joko Moersodo Beach. The results showed that the bivalves found on Joko Moersodo Beach consisted of 7 species belonging to 6 genera and 3 families, the diversity index of bivalves included moderate diversity with moderately polluted waters, and the correlation between bivalve species diversity and water lead levels and sediments on Joko Moersodo Beach showed insignificant results.