基于RS和GIS的城市化进程中河道时空演变分析——以深圳市布吉河为例

Spatiotemporal change of urban river in urbanization process based on remote sensing and GIS:A case study of the Buji River in Shenzhen City

为研究城市化对城市河道的影响,论文选择处于粤港澳大湾区的典型高度城市化流域布吉河流域为研究区,基于1988—2015年10期Landsat系列遥感影像、2003—2017年9期Google Earth高分辨率遥感影像、2019年深圳市水系图以及1980年以来的河道整治相关文献,应用RS和GIS技术,构建城市河道演变特征参数,探讨了城市化进程中河道时空格局演变规律。结果表明:①1988—2015年布吉河流域土地利用/覆被类型发生剧烈变化,流域城市化率由24.55%增至61.78%,城市化总体上表现出“先快后慢”“下游向上游”“河道两岸向周边”的时空发展特征。伴随着城市化的发展,布吉河整治经历了“整治前―防洪措施―防洪与生态措施―清淤措施”4个阶段。②河道时空格局特征受城市化影响,人口和GDP的发展对河道时空格局的演变具有驱动作用。不同地点不同城市化进程对城市河道影响不同,城市化对布吉河干支流河道影响程度存在差异。③整体上,2003—2017年布吉河地表河道比例、地表河道弯曲系数、河面率分别减少了19.06%、9.63%、1.79%,各参数与城市化均呈负相关;河床硬化率增长了6.47%,与城市化呈正相关。该研究可为中国城市化地区河道保护及防洪减灾提供参考与理论支撑。

To reveal the impact of urbanization on urban river systems,the Buji River Basin,a typical highly urbanized watershed in the Guangdong,Hong Kong and Macao Bay Area,was selected as the study area.Based on Landsat satellite images from 1988 to 2015,Google Earth high-resolution images from 2003 to 2017,the river system data in 2019,as well as literature on the river improvement projects of Shenzhen City since 1980,the characteristic indices of river channel change were constructed to evaluate the spatial and temporal evolution of the river in the process of urbanization using remote sensing data and GIS technology.The study shows that:1)From 1988 to 2015,the land use/land cover types of the Buji River Basin changed dramatically,and the urbanization rate increased from 24.55%to 61.78%.Generally,the urbanization showed the spatial and temporal characteristics of"fast first,then slowed","spreading from downstream to upstream",and"developing along the river then towards the periphery".With the development of urbanization,the improvement of the Buji River has gone through four stages:pre-improvement,flood control measures,flood control and ecological restoration measures,and dredging measures.2)The spatial and temporal evolution of the river was affected by urbanization.The increase of population and GDP has a driving effect on the river channel change.Different urbanization processes in different places have had different impacts on the river system,and urbanization has had different impacts on the main stream and tributaries of the Buji River.3)On the whole,from 2003 to 2017,the proportion of surface channel,bending coefficient of surface channel,and river surface rate of the Buji River decreased by 19.06%,9.63%,and 1.79%,respectively,which were negatively correlated with urbanization level.The river bed hardening rate was positively correlated with urbanization level,with an increase of 6.47%.This study provides a reference and theoretical support for river improvement and flood control and disaster reduction in urbanized areas of China.