Long-Term Changes in Nutrients and Phytoplankton Response in Lake Dianshan, a Shallow Temperate Lake in China

ABSTRACT

In an effort to understand algal blooms in Dianshan Lake, a shallow temperate lake in China, we analyzed more than 20 years of nutrient data (total nitrogen [TN] and total phosphorus [TP]) and lake responses (chlorophyll a. [chl a], transparency, and algal composition). We found that 1) the trophic state of Dianshan Lake transitioned from eutrophic to hypereutrophic in 1999–2000, and nutrient accumulation has accelerated since then; 2) TP was the primary limiting factor for algal biomass, with the regression coefficients of TP and chl a varying with different trophic states; and 3) TN may limit cyanobacterial growth in autumn.