<![CDATA[Penelitian ini bertujuan untuk mengetahui komposisi jenis, kelimpahan, indeks dominansi, keanekaragaman fitoplankton Sungai Code, kandungan klorofil-a serta hubungan antara konsentrasi klorofil-a dengan kelimpahan fitoplankton di Sungai Code, Daerah Istimewa Yogyakarta. Penelitian ini merupakan penelitian deskriptif kuantitatif dengan metode purposive sampling dan dilaksanakan pada bulan Januari – Maret 2021. Analisis data dijabarkan secara deskriptif serta dilakukan uji Korelasi Pearson dengan taraf signifikasi 5% atau 0,05 untuk mengetahui hubungan klorofil-a dengan kelimpahan fitoplankton. Hasil penelitian menunjukkan bahwa Komposisi fitoplankton pada Sungai Code terdiri dari 10 kelas, 54 genus, dan 104 spesies. Kelimpahan fitoplankton berkisar antara 375 – 1215 ind/L (Oligotrofik). Indeks dominansi berkisar antara 0,103 – 0,294. Indeks Keanekaragaman berkisar antara 1,860 – 2,680. Nilai klorofil-a berkisar antara 0,236 – 20,255 µg/L. Hasil Uji Korelasi Peearson menujukkan hasil signifikasi sebesar 0,558 yang artinya sig. 0,05 dengan interprestasi yaitu terdapat hubungan korelasi yang tidak signifikan antara konsentrasi klorofil-a dengan kelimpahan fitoplankton di Sungai Code begitupun sebaliknya.Kata kunci: Fitoplankton, klorofil-a, Sungai CodeThe objectives of the research were to determine the composition species, abundance, dominance, diversity of phytoplankton in the River Code, Content of chlorophyll-a and the relationship between chlorophyll-a concentration with distribution of phytoplankton abundance in the River Code, Special Region of Yogyakarta. This research is quantitative descriptive with purposive sampling method. This research was conducted from January – March 2021. The data analysis was described descriptively and pearson correlation test with 5% significance level or 0.05 to determine the relationship of chlorophyll-a with the abundance of phytoplankton. The results showed that Phytoplankton in the River Code consists of 10 classes, 54 genus, and 104 species. Phytoplankton abundance has a range between 375 – 1215 individuals/L. Phytoplankton dominance index has range between 0.103 – 0.294. The Phytoplankton Diversity Index has range between 1,860 – 2,680. The concentration of chlorophyll-a has range between 0.236 – 20.255 g/L.The results of the Pearson correlation analysis showed that there was an insignificant correlation between the concentration of chlorophyll-a and the abundance of phytoplankton in the River Code and vice versa.Keywords: Phytoplankton, chlorophyll-a, The River Code]]>
