Abstract：
This paper analyzed the long-term variations in nutrients in Liaodong Bay and their potential influencing factors based on historical data from 1978 to 2019. Under the influence of both human activities and natural changes, the concentration of DIN increased approximately 4-fold from the end of the 1990s to the mid-2010s, while DIP and DSi concentrations decreased from the beginning to the end of the 1980s and have since increased again. Asynchronous changes in nutrient levels have led to changes in the nutrient composition, which has caused a series of ecological effects. The total phytoplankton abundance decreased from the 1980s to the end of the 1990s and then increased again. Additionally, the phytoplankton composition shifted from a diatom-dominated to a dinoflagellate-dominated system, and the dominant species of zooplankton changed. Harmful algal blooms (HABs) rarely occurred before the 1980s but have frequently occurred since the end of the 1990s.
摘要：
基于1978-2019年的历史数据,分析了辽东湾地区养分的长期变化及其潜在影响因素。在人类活动和自然变化的影响下，从1990年代末到2010年代中期，DIN的浓度增加了大约4倍，而DIP和DSi浓度从20世纪80年代初到末下降，此后再次增加。营养水平的异步变化导致了营养成分的变化，造成了一系列的生态效应。从1980年代到1990年代末，浮游植物的总丰度下降，然后再次增加。此外,浮游植物组成从硅藻为主转变为鞭毛藻为主的系统，浮游动物的优势种发生了变化。有害藻华（HAB）在1980年代之前很少发生，但自1990年代末以来经常发生。
