Impacts of Climate Change and Non-Point-Source Pollution on Water Quality and Algal Blooms in the Shoalhaven River Estuary, NSW, Australia
Impacts of Climate Change and Non-Point-Source Pollution on Water Quality and Algal Blooms in the Shoalhaven River Estuary, NSW, Australia
复制标题
气候变化和非点源污染对澳大利亚新南威尔士州肖尔黑文河口水质和藻华的影响
作者：
L. Wan;Xiao Hua Wang;W. Peirson
本研究量化了气候变化和营养盐污染的一些潜在影响，以确定研究区域水质变化和藻类水华的最重要因素。三个变量，空气温度和径流，代表气候变化，和营养径流，在8个假设的情况下，以确定其对水质和藻类水华的影响，校准和验证的水质模型12K。通过溶解氧、总氮和磷的浓度来评估水质。藻类水华是通过浮游植物浓度来确定的。气温每升高2 °C，水温平均升高3%，浮游植物浓度平均升高4.79%，溶解氧浓度平均降低0.48%。预测流量的减少不仅使上述现象更加显着，但也显着增加了总氮，总磷和浮游植物的浓度与相同的污染输入。在气候变化下，河口水质问题的最大原因是降雨量减少导致的径流量减少。通过调控非点源污染物排放浓度，可以改善水质。通过减少养分径流，总氮和磷浓度也降低，导致溶解氧浓度显着增加。这项研究强调了受气候变化影响的河口水质管理的最重要因素。
This study quantifies some of the potential impacts of climate change and nutrient pollution to identify the most important factors on water quality changes and algal blooms in the study region. Three variables, air temperature and streamflow, representing climate change, and nutrient runoff, were varied in eight hypothetical scenarios to determine their impact on water quality and algal blooms by the calibrated and validated water quality model QUAL2K. Water quality was assessed by the concentrations of dissolved oxygen, total nitrogen, and phosphorus. Algal blooms were identified by phytoplankton concentration. An increase in air temperature of up to 2 °C resulted in an average increase of 3% in water temperature and 4.79% in phytoplankton concentration, and an average decrease of 0.48% in dissolved-oxygen concentration. Projected decreases in streamflow not only made the above phenomenon more significant but also significantly increased the concentration of total nitrogen, total phosphorus, and phytoplankton with the same pollution inputs. Under climate change, the biggest cause of concern for estuarine water quality is reduced streamflow due to decreases in rainfall. Water quality improvement is possible by regulating the concentration of non-point-source pollution discharge. By reducing nutrient runoff, the total nitrogen and phosphorus concentrations were also reduced, resulting in a significant increase in the dissolved oxygen concentration. This study highlights the most significant factors for managing water quality in estuaries subject to climate change.