Penelitian tentang struktur komunitas hidrofita di Situ Agathis Kampus Universitas Indonesia Depok, Jawa Barat telah dilakukan pada bulan Juni--Juli 2011. Penelitian bertujuan untuk mengetahui struktur komunitas hidrofita yang meliputi keanekaragaman, dominansi, frekuensi, kerapatan, dan nilai penting di Situ Agathis. Analisis vegetasi tumbuhan dilakukan dengan metode purposive random sampling pada daerah inlet, midlet, dan outlet. Sampel tumbuhan yang diperoleh diidentifikasi menggunakan buku identifikasi tumbuhan air. Hasil penelitian menunjukkan terdapat 14 jenis hidrofita di Situ Agathis. Hasil penelitian juga menunjukkan bahwa keanekaragaman jenis hidrofita di Situ Agathis tergolong ?sedang? dan penyebaran jenis cukup merata; akan tetapi kesamaan jenis ?kurang sama? antara daerah inlet, midlet, dan outlet perairan. Jenis Eichhornia crassipes merupakan tumbuhan yang mendominasi dan memiliki nilai penting tertinggi di perairan Situ Agathis.

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A research regarding the community structure of hydrophyte in Lake Agathis at the University of Indonesia (UI) Campus Depok, West Java, has been conducted from June--July 2011. The research was aim to understand the community structure of hydrophyte, which include biodiversity, dominance, frequency, density, and importance values in Lake Agathis. The vegetation analysis for all area of study were done using the purposive random sampling method. The plant samples that were collected were then identified based on the morphological character using the hydrophyte identification book. Fourteen plant species were found in Lake Agathis. The result shows that the hydrophyte biodiversity in Lake Agathis was in a ?medium- abundant? category, the species dispersal was in an ?evenly enough? category, however the diversity of the inlet, midlet, and outlet area were ?dissimilar?. Eicchornia crassipes was the dominance species which also has the highest importance value in Lake Agathis.