Nutrient Limiting Factor for Enabling Algae Growth of Rawapening Lake, Indonesia

Abstract

Two important issues for establishment of nutrient criteria are identifying which nutrient limits algal growth and determining the concentration of that nutrient enabling nuisance growths. The purposes of this research were: 1) to examine the nutrient (TN, TP, ratio of TN/TP) dynamic in Rawapening Lake spatially and temporally, 2) to identify Nutrient Limiting of Algal Growth in Rawapening Lake, and 2) to determine the nutrient criteria for enabling algae growth in Rawapening Lake. The research was conducted using a survey method in 7 sites from February to August 2016. The result showed that spatially Total Nitrogen (TN) and Total Phosphor (TP) in the lake were not evenly distributed and temporally influenced by the inflow. The development of algae biomass in Rawapening Lake determined ratio of TN/TP. Nutrient criteria as follow: oligotrophic was 5.96 -14.39, mesotrophic was 14. 39 -42.15, eutrophic 42.15 -51.65, and hyper-eutrophic > 51.65. These criteria could be used in designing controlling eutrophication problem by arranging nutrient input from both external and internal sources in order to meet those limit. The benefits of research contributes to the development of environmental monitoring methods to assess the trophic status using more appropriate in accordance with the conditions of the tropics region. It also could be used for consideration in policy direction and orientation of land use in catchment areas in relation to water quality of the lake.

Quality of Plankton and Physic-chemical Factors to Support Fisheries and Community Care in Babon River, Semarang, Central Java, Indonesia

“…This can be found in dam water where the current is the lowest, highest in nutrition (highest nitrate concentration), and highest plankton abundance. The high trend nitrate here is consistent with previous research [28]. The highest temperature is measured in Kalikayen village, upstream, due to the shallow water body water (ripple body water).…”

Physico-Chemical and Biological Water Quality of Tuntang Estuary, Demak, Central Java as A Base for Sustainable River Management

“…Therefore, the longshore wind in the Tuntang Estuary affects the coastal morphology (Wirasatriya et al, 2017). This current research differs from previous research focusing on the eutrophication in Rawapepning Lake, whose lot is to the Tuntang River (Soeprobowati et al, 2012;Piranti et al, 2018), or spatial distribution of Pb, Cd, and coliform in Demak (Tjahyono & Suwarno, 2018). The water quality status of the upstream Tuntang River has been studied (Saputro & Siwiendrayanti, 2023).…”

Tumbuhan Air Invasif Berpotensi sebagai Fitoremediator Bahan Organik Total (BOT) di Waduk Darma Kuningan

“…Air limbah dan KJA berpotensi besar penyuplai polutan organik (Prayuda et al, 2017) dari sisa pakan dan metabolisme ikan yang dibudidayakan. Polutan organik meningkatkan laju eutrofikasi (Heriyanto et al, 2018); (Haroon & Abd Ellah, 2021), jika perairan sudah tidak lagi memiliki daya lenting terhadap daya serap nutrient (Piranti et al, 2018). Utrofikasi adalah pengkayaan nutrisi, terutama nitrogen (N) dan fosfat (P) dengan indikator bloomingnya fitoplankton dan tumbuhan air seingga menyebabkan degradasi kualitas air waduk dan mengganggu keseimbangan ekologi (Astuti et al, 2022).…”