【摘 要】
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Tidal creeks are the main channels of land-sea ecosystem interactions,and their high dynamics are an important factor affecting the hydrological connectivity of tidal flats.Taking the Yellow River Delta as the research area,we selected remote sensing imag
【机 构】
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College of Resource Environment and Tourism,Capital Normal University,Beijing 100048,China;MCA Key L
论文部分内容阅读
Tidal creeks are the main channels of land-sea ecosystem interactions,and their high dynamics are an important factor affecting the hydrological connectivity of tidal flats.Taking the Yellow River Delta as the research area,we selected remote sensing images ob-tained during five periods from 1998 to 2018 as the data sources.Based on the spatial anal-ysis function in GIS,the typical morphological characteristics of tidal creeks,such as the level,length,density,curvature,bifurcation ratio,and overmarsh path length(OPL),were extracted to characterize the degree of development of the tidal creeks in the Yellow River Delta wet-lands.The spatio-temporal evolution of the tidal creeks was studied,and the development process and the characteristics of the tidal creeks during the different stages of development were investigated.The results revealed that(1)The number,density,and bifurcation ratio of tidal creeks exhibit an increasing trend,but the growth of the trend is slowing.The number of tidal creeks increased by 44.9%from the initial stage of the Yellow River diversion to the late stage of the wetland restoration,but it only increased by 26.2%from the late stage of the wetland restoration to the slow expansion of the Spartina alterniflora.(2)The curvature of the tidal creeks on the landward side is greater than that on the seaward side.(3)The develop-ment degree of tidal creek has spatial heterogenetiy,which is Area Ⅲ>Area Ⅱ>Area Ⅰ.(4)The drainage efficiency is significantly correlated with the tidal creak density and bifurcation ratio.Based on the analysis of the various morphological parameters and the drainage effi-ciency,it was found that after the rapid change in the tidal creek system in the early stage,the tidal creeks entered a state of slow change,and the development state of the tidal creeks tends to be in dynamic balance.The results of this study are expected to provide scientific support for the sustainable development and utilization of coastal tidal flats.
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