2017年夏季红沿河附近海域溶解态营养元素时空分布特征

Temporal and Spatial Distributions of Dissolved Nutrients in the Hongyanhe Coastal Area in Summer of 2017

通过2017年7月和8月辽东湾东南部海域两个航次的营养盐的实测数据,对该海域溶解态营养元素的浓度、分布及其主要影响因素进行了分析。结果表明:夏季红沿河附近海域氨氮(NH4-N)是DIN的主要存在形态,DON是溶解总氮(DTN)的主要存在形态。除NH4-N外,8月航次溶解态无机营养元素浓度均高于7月,而溶解态有机营养元素浓度则低于7月。各种形态营养元素浓度最高值均位于近岸区,总体来说,近岸区营养盐的浓度普遍高于离岸区,河口区营养盐浓度高于非河口区。由河流输入和人类活动引起的陆源输入对该海域营养盐浓度的高低和分布有重要的影响。水团的运动和生物活动也是影响该海域营养盐分布的关键因素。按照化学计量限制的评估方法,绝大部分海域属于磷限制性海域。人类活动导致陆源营养盐输入是红沿河附近海域营养盐的主要来源,也是其水体营养结构失衡的关键原因所在。

Based on the survey in the Hongyanhe coastal area in July and August,2017,the distribution characteristics of nutrients and their impact factors were analyzed.The results showed that ammonium(NH 4-N)is the predominant speciation of DIN,and DON is the predominant speciation of dissolved total nitrogen(DTN).Except NH 4-N,the concentration of dissolved inorganic nutrients in August was higher than that in July,while the concentration of dissolved organic nutrients was lower in July.Influenced by the terrestrial input,the concentration of dissolved inorganic nutrients in the coastal area is higher than that of offshore area.The terrestrial input caused by river and human activities plays an important impact on distribution of nutrients.The water mass movement and biological activities are also important factors affecting the distribution of nutrients.According to the assessment method of stoichiometric limits,most of the studied area belong to the phosphorus-restricted.The terrigenous input due to human activities was the major nutrients source and the key factors affecting the imbalance of the nutrients structure.