基于随机森林的入海污染源对海湾环境容量的影响排序研究

海水水质对海湾生态系统健康具有重要影响，而基于环境容量的入海污染物总量控制是改善海湾水体质量的前提和基础。本研究从分析水质目标约束下污染源对环境容量影响的非线性关系入手，结合随机森林（random forest）分类方法和常规水质模型，对海南省陵水县新村潟湖入海污染源对海湾环境容量的影响进行了研究。结果显示，在渔排养殖、城镇污水和径流注入3类共41个影响潟湖无机氮和活性磷酸盐浓度的主要污染源中，10个污染源对环境容量存在全局性影响；渔排养殖是影响潟湖无机氮环境容量的主要因素；渔排养殖、城镇污水和径流注入污染源对活性磷酸盐环境容量的影响程度差异不大。

Impact ranking of pollution source discharge on the bay environmental capacity based on the random forest algorithm

Marine water quality is of importance to the health of the bay ecosystem. For improving the water quality, the total pollutant discharge control of sea areas based on the environmental capacity is the primary means. In this paper, under the water quality requirements and the nonlinear relationship between pollution sources and environmental capacity, the impact of pollution sources discharging into Xincun lagoon was studied. The combination of random forest algorithm and the conventional water quality model was employed in the analysis process. The results showed that among the 41 pollution sources from three categories, i.e., fishing raft culture, urban sewage and river runoff, 10 pollution sources had an overall impact on inorganic nitrogen and phosphate environmental capacity. Among the three categories, fishing raft culture is the main one affecting the inorganic nitrogen environmental capacity. However, in terms of the phosphate environmental capacity, the impact from three types of pollution sources makes a slight difference.