1996—2020年长江口九段沙湿地植被覆盖对潮沟演变规律的影响  

Effect of fractional vegetation cover on the evolution of tidal creeks of the Jiuduansha shoal in Yangtze River Estuary (China) during 1996—2020

作　　者：劳聪聪 辛沛 左寅 程海峰 LAO Congcong;XIN Pei;ZUO Yin;CHENG Haifeng(State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China;Key Laboratory of Estuarine and Coastal Project,Ministry of Transport,Shanghai Estuarine and Coastal Science Research Center,Shanghai 201201,China)

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [2]上海河口海岸科学研究中心河口海岸交通行业重点实验室,上海201201

出　　处：《水科学进展》2022年第1期15-26,共12页Advances in Water Science

基　　金：国家自然科学基金资助项目(U2040204);江苏省杰出青年基金资助项目(BK20200020)。

摘　　要：长江口九段沙湿地是国家级自然保护区,认识植被覆盖与潮沟网络间的关系对保护九段沙湿地意义重大。基于长时序Landsat和HJ-1A多光谱图像,提取并分析长江口九段沙湿地潮沟和植被覆盖度数据。结果表明:①1996—2020年间,潮沟总长度以每年11.71 km速度增加,植被覆盖面积以每年4.79 km^(2)速度增加,至2020年潮沟等级最高为四级;②历年潮沟分布特征变化与高植被覆盖度区域密切相关;③各级别潮沟中,一级潮沟对潮沟网络的平均归槽水流长度影响最大,而不同植被覆盖参数中,植被覆盖面积影响最大;④平均归槽水流长度与植被覆盖面积符合指数函数关系,随着植被覆盖面积的增大,平均归槽水流长度逐渐减小,即潮沟网络排水效率增大。The Jiuduansha shoal(JDS,in Yangtze River Estuary,China)is a national nature reserve.Understanding the relationship between fractional vegetation coverage and tidal creeks is significant to the JDS protection.In this study,the distribution of tidal creeks and fractional vegetation coverage in JDS were extracted and analyzed based on long-time series Landsat and HJ-1A multispectral images during 1996—2020.The results indicate that the total length of tidal creeks increased by 11.71 km/a during 1996—2020.The vegetation coverage increased by 4.79 km^(2)/a.In 2020,the highest order of tidal creeks was fourth.The distributions of tidal creeks were closely related to high vegetation coverage areas.Among the different orders of tidal creeks,those at the first order significantly affect the overmarsh path length(L_(OP)).Among the different vegetation coverage parameters,the impact of the vegetation coverage area on the L_(OP) was most remarkable.The relationship between the L_(OP) and vegetation coverage area satisfied an exponential function.As the vegetation coverage area increased,the L_(OP) gradually decreased.The drainage efficiency of the creek network increased.

关 键 词：潮沟 演变规律 植被覆盖度 排水效率 九段沙湿地 长江口 

分 类 号：TV122[水利工程—水文学及水资源]