Variation of DOC, nutrients and chlorophyll a contents in shrimp ponds of Minjiang River Estuary

In order to reveal the spatiotemporal dynamic changes of DOC, nutrients, chlorophyll a and their eco-chemical metrological characteristics of land-based shrimp ponds in the Minjiang River Estuary, Fujian Province, from May to October 2018, we have analyzed the water temperature, pH, salinity, dissolved oxygen. The soluble organic carbon (DOC), soluble inorganic nitrogen (DIN), PO₄ ³⁻-P and chlorophyll a mass concentration were 5.73−16.79 mg·L⁻¹, 0.04−1.80 mg·L⁻¹, 0.03−0.16 mg·L⁻¹ and 15.02−443.08 μg·L⁻¹, respectively, all with obvious characteristics of spatio-temporal changes. The concentrations of DOC, nutrients and chlorophyll a were affected by the water environment parameters, human activities and cultured organisms. The water nutrient composition of carbon, nitrogen and phosphorus was similar with that of plants and soil, showing carbon surplus and nitrogen limitation. In summary, In the process of aquaculture, it is very important to strengthen the monitoring of the dynamic changes of nutrients and chlorophyll a in shrimp ponds, and artificially adjust the ratio of carbon, nitrogen and phosphorus, so as to prevent eutrophication of shrimp pond and promote the green and sustainable production of ecosystem of shrimp ponds.