{"title":"Multi-Scale Influence and Time-Lag Effect Analysis of Precipitation Process on Vegetation Diversity of Grassland in Poyang Lake","authors":"Yuanyuan Ding, Wenbo Chen, Zhuozhao Chen","doi":"10.1002/eco.70088","DOIUrl":null,"url":null,"abstract":"<div>\n \n <p>Precipitation significantly alters the structure and stability of wetland vegetation ecosystems, particularly under increasing global climate change. Analysing the multi-scale mechanism and ecological effects of precipitation on wetland vegetation diversity patterns is crucial for wetland ecological restoration and biodiversity conservation. Based on the analysis of spatiotemporal heterogeneity and variation of the precipitation process, this paper constructed a high spatiotemporal resolution vegetation dynamic dataset of Poyang Lake by integrating multi-source remote sensing data and a machine learning method, and reveals the multi-scale influences and time lag effects of the precipitation process on the vegetation diversity pattern. The results showed as follows: (1) The spatial distribution of precipitation in Poyang Lake was unbalanced, and exhibited an overall increasing trend, with the precipitation intensity index showing non-stationary characteristics relatively. (2) From 2000 to 2020, vegetation diversity exhibited significant spatiotemporal heterogeneity. Increased vegetation landscape dominance was associated with a decrease in diversity and evenness indices, shifting the landscape distribution from balanced to unbalanced. (3) Vegetation diversity exhibited a notable lag in its response to precipitation, with the timing and magnitude of the response varying depending on the precipitation distribution and timescale. At the monthly scale, precipitation exhibited a negative correlation with Shannon diversity index (SHDI), Shannon evenness index (SHEI) and richness index (PT), but a positive correlation with Shannon dominance index (DI). The response intensity of the vegetation diversity pattern to precipitation followed the order: precipitation of month (PM), maximum 5-day precipitation amount (RX5day), and maximum 1-day precipitation amount (RX1day). The response of the vegetation diversity pattern to PM displayed both time-lag and cumulative effects. At the annual scale, annual total wet days precipitation (PRCPTOT) and precipitation frequency indices (R20, R25) significantly influenced the vegetation diversity pattern within the same year. The precipitation intensity index exerted a significant influence on the vegetation diversity pattern primarily with a 3–4 year lag. The influence of the precipitation process on the vegetation diversity pattern has a strong relationship with its instability characteristics. Our findings can offer valuable insights for the conservation and restoration of wetland vegetation diversity, and provide a scientific foundation for the sustainable management of the lake ecosystem.</p>\n </div>","PeriodicalId":55169,"journal":{"name":"Ecohydrology","volume":"18 5","pages":""},"PeriodicalIF":2.1000,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ecohydrology","FirstCategoryId":"93","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/eco.70088","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ECOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Precipitation significantly alters the structure and stability of wetland vegetation ecosystems, particularly under increasing global climate change. Analysing the multi-scale mechanism and ecological effects of precipitation on wetland vegetation diversity patterns is crucial for wetland ecological restoration and biodiversity conservation. Based on the analysis of spatiotemporal heterogeneity and variation of the precipitation process, this paper constructed a high spatiotemporal resolution vegetation dynamic dataset of Poyang Lake by integrating multi-source remote sensing data and a machine learning method, and reveals the multi-scale influences and time lag effects of the precipitation process on the vegetation diversity pattern. The results showed as follows: (1) The spatial distribution of precipitation in Poyang Lake was unbalanced, and exhibited an overall increasing trend, with the precipitation intensity index showing non-stationary characteristics relatively. (2) From 2000 to 2020, vegetation diversity exhibited significant spatiotemporal heterogeneity. Increased vegetation landscape dominance was associated with a decrease in diversity and evenness indices, shifting the landscape distribution from balanced to unbalanced. (3) Vegetation diversity exhibited a notable lag in its response to precipitation, with the timing and magnitude of the response varying depending on the precipitation distribution and timescale. At the monthly scale, precipitation exhibited a negative correlation with Shannon diversity index (SHDI), Shannon evenness index (SHEI) and richness index (PT), but a positive correlation with Shannon dominance index (DI). The response intensity of the vegetation diversity pattern to precipitation followed the order: precipitation of month (PM), maximum 5-day precipitation amount (RX5day), and maximum 1-day precipitation amount (RX1day). The response of the vegetation diversity pattern to PM displayed both time-lag and cumulative effects. At the annual scale, annual total wet days precipitation (PRCPTOT) and precipitation frequency indices (R20, R25) significantly influenced the vegetation diversity pattern within the same year. The precipitation intensity index exerted a significant influence on the vegetation diversity pattern primarily with a 3–4 year lag. The influence of the precipitation process on the vegetation diversity pattern has a strong relationship with its instability characteristics. Our findings can offer valuable insights for the conservation and restoration of wetland vegetation diversity, and provide a scientific foundation for the sustainable management of the lake ecosystem.
期刊介绍:
Ecohydrology is an international journal publishing original scientific and review papers that aim to improve understanding of processes at the interface between ecology and hydrology and associated applications related to environmental management.
Ecohydrology seeks to increase interdisciplinary insights by placing particular emphasis on interactions and associated feedbacks in both space and time between ecological systems and the hydrological cycle. Research contributions are solicited from disciplines focusing on the physical, ecological, biological, biogeochemical, geomorphological, drainage basin, mathematical and methodological aspects of ecohydrology. Research in both terrestrial and aquatic systems is of interest provided it explicitly links ecological systems and the hydrologic cycle; research such as aquatic ecological, channel engineering, or ecological or hydrological modelling is less appropriate for the journal unless it specifically addresses the criteria above. Manuscripts describing individual case studies are of interest in cases where broader insights are discussed beyond site- and species-specific results.