2015—2017年江西南昌军山湖水体营养状态演变特征

Evolution Characteristics of Trophic Status in Junshan Lake in Nanchang Jiangxi Province From 2015 to 2017

本文比较了各种水体富营养化评价方法的优劣,选用综合营养状态指数法评价了2015—2017年江西省南昌市军山湖水质和水体营养状况,结合Arcgis中"创建渔网"和"反距离权重"工具生成了军山湖综合营养指数空间分布图。结果表明:(1)军山湖水质逐年恶化,2015、2016和2017年综合营养指数变化范围分别为24.34~31.75、25.17~35.62和26.43~46.20,2015年军山湖水体营养状态以贫营养为主,至2017年以中营养为主,综合营养指数值中处于中营养等级的水面积占比由2015年的47.5%升至2017年的78.3%;(2)水产养殖在湖泊的营养等级上升中贡献较大,养殖区域水体的综合营养指数偏高;(3)军山湖南半部分水体综合营养指数值比北半部分水体高,转化为轻度富营养等级风险较大;(4)使用Arcgis中"创建渔网"和适宜的插值工具可一定程度上提高富营养化评价结果的精度。本研究结果可为军山湖水资源调度及管理提供参考。

The comprehensive nutritional status index method was used to evaluate the water trophic status and spatial diagram of the water quality in Junshan Lake from 2015 to 2017 by Arcgis software based on comparison of advantages and disadvantages of various evaluation methods for water eutrophication.It was found that the quality in Junshan Lake was deteriorated year by year,primarily oligotrophic in 2015,and medium trophic in 2017.The proportion of water in the mid-trophic level of the comprehensive nutrition index was increased from 47.5%in 2015 to 78.3%in 2017.There was high comprehensive nutrient index in water bodies in aquaculture areas,and higher comprehensive nutrient index in south part of Junshan Lake than that in north part.The findings indicate that"create fishing nets"and"interpolatio"tools in Arcgis can improve the accuracy of eutrophication evaluation.