引用本文: | 顾洋,张平究,秦风约,蔡永久,王晓龙.流域景观格局演变对河流水质的影响——以巢湖流域南淝河为例.湖泊科学,2024,36(6):1769-1781. DOI:10.18307/2024.0624 |
| Gu Yang,Zhang Pingjiu,Qin Fengyue,Cai Yongjiu,Wang Xiaolong.Impact of the evolution of watershed landscape pattern on river water quality—The example of the Nanfei River, Lake Chaohu Basin. J. Lake Sci.2024,36(6):1769-1781. DOI:10.18307/2024.0624 |
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摘要: |
景观格局由景观组成、地理特征和景观配置等方面共同组成,流域景观格局演变是河流水质时空变化的重要驱动因素。为探讨景观格局演变对城市地区典型河流水质的定量影响与作用机制,本研究基于巢湖流域南淝河2013年与2023年水质数据和土地利用数据,采用单因素ANOVA检验、层次聚类法探究水质时空变化,通过Bioenv分析、VPA分析等多元统计方法探究在不同时空尺度下景观格局中的各个部分对水质综合营养状态指数(TLI)的解释率以及影响TLI的关键因子。结果表明:2023年南淝河水质优于2013年,总氮、总磷和TLI在2013年显著高于2023年,但不同年份水质的季节差异并不一致。不同时期的调查结果均发现,非汛期景观格局对TLI的解释率高于汛期,1000 m河岸带缓冲区和子流域尺度下景观格局对TLI影响较大。景观组成、地理特征对TLI的独立解释率大于景观配置;景观配置对TLI的影响主要集中在与景观组成、地理特征的联合作用中。在景观组成中,建设用地面积占比、园地面积占比与TLI呈显著正相关,水域面积占比与TLI呈显著负相关。在地理特征中,面积高程积分、地形湿度指数与TLI呈显著负相关。研究认为,未来南淝河流域要限制“源”景观的无序扩张,不可忽视地理特征对河流水质的优化作用,并从景观配置中的“复杂度、破碎度和连通性”等方面着手对城市进行合理规划以辅助改善水质。 |
关键词: 景观格局演变 水质 综合营养状态指数 非点源污染 南淝河 巢湖流域 |
DOI:10.18307/2024.0624 |
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基金项目:国家自然科学基金项目(41971147)、巢湖流域山水林田湖草监测体系建设项目(调查评估部分)(2022BFAWZ02436)和江西省“双千计划”长期项目(JXSQ2023101034)联合资助。 |
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Impact of the evolution of watershed landscape pattern on river water quality—The example of the Nanfei River, Lake Chaohu Basin |
Gu Yang1,2, Zhang Pingjiu2, Qin Fengyue1, Cai Yongjiu1, Wang Xiaolong1
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1.Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China;2.School of Geography and Tourism, Anhui Normal University, Wuhu 241002, P. R. China
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Abstract: |
Landscape pattern consists of landscape composition, geographic features, and landscape configuration. The evolution of landscape pattern in watersheds plays a pivotal role in shaping spatial and temporal variations in river water quality. In order to quantitatively explore the impact and mechanism of landscape pattern evolution on water quality of typical rivers in the plains river network area, this study was based on the water quality data and land use data of the Nanfei River, Lake Chaohu Basin in 2013 and 2023 and used the one-way ANOVA test and hierarchical clustering method to analyze the spatiotemporal changes of water quality. Multivariate statistical methods such as the Bioenv analysis and the VPA analysis were utilized to examine the interpretation rate of various components of landscape pattern on the comprehensive trophic level index (TLI) of water quality and identify the key factors influencing TLI at different spatiotemporal scales. The results showed that the water quality of the Nanfei River in 2023 was better than that in 2013, and total nitrogen (TN), total phosphorus (TP), and TLI were significantly higher in 2013 than in 2023, but the seasonal differences in water quality were not consistent across years. The results of the survey in different periods showed that the landscape pattern in the non-flood season explained the TLI more than the flood season, and the landscape pattern at the 1000m buffer and sub-basin scales had a greater influence on the TLI. The independent explanation rate of landscape composition and geographic features on TLI was higher than that of landscape configuration; the influence of landscape configuration on TLI mainly concentrated in its joint effect with landscape composition and geographic features. In landscape composition, the proportion of building and garden plot area was significantly positively correlated with TLI, while the proportion of water area was significantly negatively correlated with TLI. Among the geographic features, the area hypsometric integral (HI) and topographic wetness index (TWI) were significantly negatively correlated with TLI. The study concluded that in the future, the restoration of Nanfei River Basin should limit the uncontrolled expansion of the “source” landscape, and should not ignore the optimization of geographic features on the water quality of the river. The landscape configuration of the “complexity, fragmentation, and connectivity” and other aspects of the rational planning of the city will be important to assist in the improvement of water quality. |
Key words: Landscape pattern evolution water quality integrated trophic level index nonpoint source pollution Nanfei River Lake Chaohu Basin |