农业工程学报2019，Vol.35Issue(20)：118-124,7.DOI:10.11975/j.issn.1002-6819.2019.20.015
三峡水库典型支流消落带泥沙颗粒态磷复合指纹示踪研究
Fingerprinting particulate phosphorus absorbed by sediments for riparian zone deposits in tributary of Three Gorges Reservoir
摘要
Abstract
Information on deposited sediment and associated particulate phosphorus (PP) is of great importance for development of effective management strategies in the riparian zone of the Three Gorges Reservoir. In this study, a composite fingerprinting approach was used to identify the sources of deposited sediment and associated PP in the riparian zone with different elevations (145-155, >155-165, >165-175 m) along the Ruxi tributary channel. Three potential sediment sources were defined: the topsoil above the 175 m elevation level of the riparian zone, and the suspended sediments transported by both the mainstream of Yangtze River and the upstream Ruxi River. The target deposited sediments were collected at different elevation levels of the riparian zone along the Ruxi River and a total of 18 geochemical properties factors were analyzed for the size fraction of sediment smaller than 63 μm. A commonly used 3-step (range test, KW-H test and DFA analysis) statistical methodology to element selection was applied to select the optimum subset of tracer properties that could best discriminate sources. The relative contribution of the 3 potential sources to the deposited sediment in the riparian zone was estimated using a frequentist-based multivariate mixing model. The relative importance of those sources to the overall PP was then determined by combining the information obtained from deposited sediment sources with information on the P content of those sources. Source apportionment results showed that the suspended sediments transported by both the Yangtze mainstream and the upstream Ruxi tributary represent the dominant sources of PP deposits in the riparian zone, which account for 88.6%-95.4% of the PP input. The corresponding sediment contribution from these 2 sources ranged from 69.7% to 84.2%, which varied between elevation levels. The PP contribution from the Yangtze mainstream was 54.5% for the >165-175 m level. The relative PP contribution from the Ruxi River was the most important during the early wet season, which was 51.6% (145-155 m). In contrast, the PP input from the topsoil above the 175 m level of the riparian zone exhibited to be less important (mean of 8.5%) during the study period. The information on sediment contribution of this source reveals that most of the eroded sediment from the topsoil above the 175 m level was preferentially deposited in the elevation levels of <155-165 m and >165-175 m. The findings of this research highlight the important impacts of impoundment on the riparian zone of the tributaries of the reservoir in terms of sediment accumulation and pollution.关键词
磷/泥沙/元素/消落带/复合指纹技术Key words
phosphorus/ sediments/ elements/ riparian zone/ composite fingerprinting technique分类
化学化工引用本文复制引用
陈太丽,史忠林,王永艳,严冬春,文安邦,陈佳村..三峡水库典型支流消落带泥沙颗粒态磷复合指纹示踪研究[J].农业工程学报,2019,35(20):118-124,7.基金项目
国家重点研发计划"构建源头削减-生物隔离-湿地消纳相结合的高效生态拦截技术体系"(2017YFD0800505) （2017YFD0800505）
国家自然科学基金"三峡库区支流消落带土-水界面磷素迁移过程与通量"(41430750) （41430750）
