• 关键词：污染负荷  时空变化特征  多元统计法  沱江流域

• 基金项目：四川省科技计划重点研发项目（No.2019YFS0057）；国家自然科学基金（No.41601088）

• 肖宇婷
• 西南科技大学环境与资源学院, 绵阳 621010

• 谌书
• 西南科技大学环境与资源学院, 绵阳 621010

• 樊敏
• 西南科技大学环境与资源学院, 绵阳 621010

• 摘要：选取沱江流域为研究区域，采用排污系数法对2007、2017年沱江流域28个区县的总磷（TP）、总氮（TN）、氨氮（NH₃-N）和化学需氧量（COD）的污染负荷进行估算，并使用相关分析、主成分分析、聚类分析和空间分析法揭示流域污染负荷时空变化与社会经济因素及土地利用方式的相互作用关系.结果表明：①4种污染负荷在时间尺度上呈整体增加趋势，空间尺度上呈高度异质性.其中，COD污染负荷增长量和增长率最大，分别为87556.54 t、24.16%.上游龙泉驿区COD、NH₃-N污染负荷增加量最大，分别为7988.15、469.83 t，而TN和TP增加量最大的区域出现在下游的龙马潭区和泸县，分别为1556.08、181.93 t.②污染负荷与农业经济社会指标相关性较强，COD、NH₃-N、TN和TP污染负荷与非农业人口数量的相关系数分别由2007年的0.460、0.218、0.226和0.184变为2017年的0.953、0.938、0.881和0.871，且农业用地和建设用地大面积分布的地区污染更加严重.③4种污染负荷的污染源聚类结果均发生变化，这与其他污染源类型向城镇污染源类型转变相关，发生转变的区县多数集中在农业用地和建设用地大面积分布的区域，且这些区域城镇化率或二、三产业占生产总值比的变化量均较大，如中游的乐至县、雁江区、东兴区等.聚类未发生变化的区县对应的土地利用类型主要为林地和草地，其城镇化率或二、三产业占生产总值比的变化量均较小，如下游的自流井区和中游的内江市市中区等.对沱江流域污染负荷时空变化特征的探讨可为该流域污染物总量调控和环境健康发展提供理论依据和数据支撑.

• Abstract：With the economic development and population growth, the water pollution turns more serious in recent years. Therefore, it is necessary to quantify the pollution load discharge for watershed management and planning. In this study, the Tuojiang River Basin was selected as the study site. Firstly, we evaluated the main pollution loads (including chemical oxygen demand (COD), ammonia (NH₃-N), total nitrogen (TN) and total phosphorus (TP)) located in 28 counties or districts of Tuojiang River Basin during the period of 2007—2017 based on the emission coefficient method. Secondly, we revealed the relationships between spatiotemporal variation of pollution loads and socio-economic driving factors as well as the land use patterns by multivariate statistical analysis methods (containing correlation analysis, principal component analysis, cluster analysis) and spatial analysis technologies. The results showed that: ①overall increasing trends were observed for all four kinds of pollution loads during 2007—2017 period with highly heterogeneous spatial variation. Compared to other three pollution loads, the magnitude and rate of COD pollution load increment were the largest with the value of 87556.54 t and 24.16% accordingly,. The highest increment of COD and NH₃-N pollution loads were located at Longquanyi district with the values of 7988.15 t and 469.83 t, respectively. While for the TN and TP pollution loads, the highest increment were found at Longmatan and Lu counties with the values of 1556.08 t and 181.93 t, respectively. ②The correlation coefficients of COD, NH₃-N, TN and TP pollution loads against the non-agricultural population raised from 0.460, 0.218, 0.226, 0.184 in 2007 to 0.953, 0.938, 0.881 and 0.871 in 2017, respectively. Among all land uses, the agricultural and construction lands contributed to the most serious pollution. ③The clustering results of pollution sources for all pollution loads changed to some extent which mainly related to the transformation towards urban pollution sources. In general, counties with main land use type of agricultural and construction land were often subjected to the changed clustering categories. In addition, the variation of urbanization rate or the ratio of secondary and tertiary industries to GDP were usually quite large in those areas (such as Lezhi, Yanjiang and Dongxing in the middle reaches). In contrast, non-changed clustering categories were observed in the regions with more woodland and grassland areas (for example, Ziliujing in the lower reaches and central of Neijiang in the middle reaches, etc). Similarly, the variation of urbanization rate or the secondary and tertiary industries to GDP in these areas were also lower. In summary, this paper revealed the temporal and spatial characteristics of pollution loads originated from different pollution sources in Tuojiang River Basin. The proposed research framework and related results could provide theoretical basis and data support for the total pollution control and the sustainable development of the environment in the watershed.

• Key words：pollution load  temporal and spatial variation characteristics  multivariate statistical method  Tuojiang River Basin

• 
  摘要点击次数： 501 全文下载次数： 538