Komposisi Dan Kelimpahan Fitoplankton Di Laguna Segara Anakan, Cilacap

Abstract

Segara Anakan merupakan laguna yang terletak di selatan Pulau Jawa tepatnya di perbatasan antara Jawa Barat dengan Jawa Tengah. Kawasan Segara Anakan merupakan tempat bertemunya sungai besar, sehingga mengalami perubahan penurunan kualitas perairan berupa penyempitan dan pedangkalan akibat proses sedimentasi yang tinggi. Hal ini dikhawatirkan dapat mengakibatkan menurunnya kualitas perairan yang dapat mengganggu pertumbuhan fitoplankton di perairan. Fitoplankton merupakan parameter biologi yang dapat dijadikan bioindikator untuk mengevaluasi kualitas dan tingkat kesuburan suatu perairan. Kondisi tentang lingkungan perairan diperkirakan berubah sepanjang waktu, maka perlu penelitian fitoplankton, untuk mengetahui tingkat kesuburan perairannya. Tujuan dari penelitian ini adalah untuk mengetahui komposisi dan kelimpahan fitoplankton di Laguna Segara Anakan, Cilacap. Penelitian ini menggunakan metode deskriptif eksploratif dengan pengambilan data menggunakan purposive sampling method. Hasil menunjukkan ditemukan 34 genera yaitu Kelas Bacillariophyceae (21 genera), Kelas Cyanophyceae (4 genera), Dinophyceae (6 genera), Chlorophyceae (2 genera), dan Euglenophyceae (1 genus). Kelimpahan fitoplankton berkisar antara 12.945,8-38.194,1 sel/liter. Indeks Keanekaragaman termasuk kategori sedang dengan nilai berkisar 1,60 - 2,32. Indeks keseragaman termasuk kategori sedang hingga tinggi, dengan nilai berkisar 0,59 - 0,81. Indeks dominansi berkisar antara 0,18 - 0,44. menunjukkan bahwa tidak ada genus yang mendominasi. Segara Anakan is a lagoon located in the south of Java Island precisely on the border between West Java and Central Java. Segara Anakan area is the place where the big river meets. Water quality decrease because of narrowing the lagoon due to the high sedimentation process. This may affect the presence of phytoplankton in the water. The quality and the fertility level of aquatic can be evaluated through the phytoplankton existence since phytoplankton is used as a biological indicator for the marine environment. The condition of the aquatic environment is expected to change over time, so it is necessary to study phytoplankton. The purpose of this research is to know about the composition and abundance of phytoplankton in Segara Anakan Lagoon, Cilacap. This research used the descriptive explorative method by data sampling using purposive sampling method. The study showed 34 genera of Bacillariophyceae (21 genera), Cyanophyceae (4 genera), Dinophyceae (6 genera), Chlorophyceae (2 genera), and Euglenophyceae (1 genus). The abundance of phytoplankton ranging from 12.945,8-38.194,1 cells/liter. The Diversity Index is a medium category with values ranging from 1.60 to 2.32. The evenness index is moderate to high, with values ranging from 0.59 to 0.81. The Dominant index ranges from 0.18 to 0.44. The value indicates the category of no dominating genus.

The Correlation Between Plankton Abundance And Water Quality in Donan River

“…The highest abundance is station 9 with abundance 6,406 ind L -1 , while station 8 with the smallest abundance with value is 524 ind L -1 . Plankton abundance in Donan river is relatively low compared to Wiyarsih (2019) research which has abundance 29,888 ind L -1 (Table 2).…”

“…The results of the research showed that Donan river had 15 plankton genera divided into 10 genus of phytoplankton and 5 genera of zooplankton. Wiyarsih et al, (2019) has argument that the condition of estuary is very influential for plankton abundance especially potential of nitrates and phosphates as main factor to support phytoplankton growth. Sihombing & Aryawati (2013) also notes potential of nutrients such as nitrates and phosphates in the waters have high correlation with abundance of phytoplankton and zooplankton.…”

Abundance and Diversity of Diatom Class Bacillariophyceae as Bioindictaor of Pollution in the Waters of Tanjung Luar Fish Landing Based

“…Indeks dominansi tersebut menandakan bahwa tidak ada spesies Bacillariophyceae yang mendominasi perairan PPI Tanjung Luar (Odum, 1993dalam Purnamaningtyas et al, 2019. Hal serupa yang dilaporkan oleh Wiyarsih et al, (2019) 3 Ph 7 7 7 7 7 7 4 DO (mg/l) 6 6,2 7 6,8 6,8 6,56…”

The dynamics of the plankton community on Lake Siombak, a tropical tidal lake in North Sumatra, Indonesia

“…Various plankton studies have been carried out in lake waters, both natural and artificial lakes, such as Lake Pondok Lapan (Muhtadi et al 2015), Lake Toba (Rahman et al 2016), Lake Ebony (Pratiwi et al 2018a), Lake Matano (Sulawesty 2019), Lake Maninjau (Sulastri et al 2019). Some research on estuarine and mangrove waters has been widely carried out and reported, such as the Mahakam Delta, East Kalimantan (Effendi et al 2016), Belawan Estuary (Dimenta et al 2018), Segara Anakan, Central Java (Dewi et al 2019;Wiyarsih et al 2019); including bay and coastal waters, such as in Gorontalo Bay (Kadim et al 2018), Sunda Strait (Takarina et al 2019), Banten Bay, Lampung and Jakarta (Sidabutar et al 2016;Damar et al 2020). However, no research has been reported on the dynamics of plankton in tidal lakes in Indonesia.…”