气候变化与人类活动对鄱阳湖水文情势的影响研究

Impacts of climate change and human activities on hydrological regime of Poyang Lake

进入21世纪以来,受气候变化与人类活动因素叠加影响,鄱阳湖退水时间提前、枯水期延长、水位降低等问题频发,呈现出常态化、趋势化特征,给鄱阳湖湖区生产生活带来巨大挑战。运用趋势检验及突变检验的方法分析鄱阳湖湖区1989~2020年5个水文站(星子、棠荫、康山、都昌和湖口)年均水位的变化趋势;耦合可细化人类活动影响的PCR-GLOBWB(PCRaster Global Water Balance)模型与可预测时间序列的LSTM长短期记忆神经网络模型,结合IHA/RVA法,量化气候变化与人类活动对鄱阳湖的影响。结果表明:受人类活动影响,鄱阳湖水位呈现下降趋势,在2003年鄱阳湖水位发生显著变异,同时,鄱阳湖水位整体改变度由低度改变上升到中度改变。以星子站为例,人类活动是鄱阳湖水文情势变化的主要驱动因素,贡献率达110.62%,气候变化对其贡献率仅为-10.62%。研究成果可为鄱阳湖的水资源科学管理调控提供依据。

Since the beginning of the 21st century,Poyang Lake has been confronted with a series of challenges resulting from the combined effects of climate change and human activities.These challenges include early water withdrawal time,dry season duration extension,and falling water levels.The observed phenomena exhibit a normalization and trending characteristics,posing significant challenges to the production and life in the Poyang Lake area.To analyze the trends in annual average water level at five hydrological stations in Poyang Lake area from 1989 to 2020,namely Xingzi,Tangyin,Kangshan,Duchang,and Hukou Station,we employed trend and mutation tests.Additionally,we quantified the impacts of climate change and human activities on Poyang Lake by utilizing the PCR-GLOBWB(PCRaster Global Water Balance) model,which captures the refined impact of human activities,and the LSTM(long short-term memory) neural network model which is suitable for time series prediction.These models were integrated with the IHA/RVA method.The results indicated that the water level of Poyang Lake showed a downward trend due to human activities.Notably,a significant change occurred in 2003.At the same time,the overall change degree of Poyang Lake water level increased from low change to moderate change.Taking Xingzi Station as an example,human activities were the main driving factors for the change in the hydrological regime of Poyang Lake,with a contribution rate of 110.62%.In contrast,the contribution rate of climate change was only-10.62%.The research results can provide a basis for the scientific management and regulation of water resources in Poyang Lake.