北京市主城区高分辨率的城市水碳通量模拟研究  

High-resolution modeling of urban water and carbon fluxes in the main urban area of Beijing,China

作　　者：邵薇薇[1] 邵蕊 倪广恒[2] 王义成[1] 杨志勇[1] 刘家宏[1] SHAO Weiwei;SHAO Rui;NI Guangheng;WANG Yicheng;YANG Zhiyong;LIU Jiahong(State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100038,China;State Key Laboratory of Hydroscience and Engineering,Department of Hydraulic Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]中国水利水电科学研究院流域水循环模拟与调控国家重点实验室,北京100038 [2]清华大学水利水电工程系水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《水利学报》2024年第5期516-527,共12页Journal of Hydraulic Engineering

基　　金：北京市自然科学基金项目(8222036);国家自然科学基金项目(51979285,U2240223);国家重点实验室自主研究课题(SKL2022TS11);水利部重大科技项目(SKS-2022126);中国水利水电科学研究院基本科研业务费专项(WR110145B0042023)。

摘　　要：城市化通过影响地表蒸散发(ET)过程改变了区域水热平衡等水文和生态过程,进而改变了陆地生态系统的结构与功能。为科学评估城市水碳过程,基于哨兵二号卫星数据的植被信息,估算了2016—2021年逐月北京市主城区10 m×10 m空间分辨率的植被指数,进一步结合PT-JPLim四源蒸散发模型、InVEST模型以及解析型生态系统水分利用效率(WUE)模型,模拟了2016—2021年北京市主城区10 m×10 m空间分辨率的蒸散发、蒸散发分量(植被蒸腾E t、土壤蒸发E b、截留蒸发E i和不透水面蒸发E u)、总初级生产力(GPP)、碳储量以及WUE的月值,并分析了其相关关系。植被指数较大值集中在西部山区,其次为北京市的公园区域,归一化植被指数NDVI最大值为0.65。主城区多年平均蒸散发量为497 mm,ET随着叶面积植被指数LAI和增强植被指数EVI的增加而增加。2016—2021年期间,NDVI、LAI和EVI分别以每年0.0048、0.016 m^(2)·m-2和0.0047的速度增加。区域平均E t为141.51 mm,E i为50.77 mm,E b为272 mm,不透水面上的E u ET为18.2%。碳储量较高的区域主要分布在西部山区,该区域海拔相对较高,植被覆盖率较高,总碳储量密度高值超过5 t hm^(2)。研究区GPP的平均值为2.7 g·m^(-2)·d^(-1),多年平均WUE为0.63 g·mm^(-1)。WUE和E t ET呈显著负相关(R=-0.44,p<0.001),WUE随GPP的增加呈现显著的上升趋势。精细化的城市水碳模拟能够为海绵城市的建设和评估提供理论基础,对“双碳”目标的实现具有重要意义。Urbanization alters hydrological and ecological processes,such as regional water-heat balance,by affecting surface evapotranspiration(ET)processes,which in turn changes the structure and function of terrestrial ecosystems.To scientifically assess the urban water-carbon process,this study estimated the monthly vegetation index at 10 m×10 m spatial resolution in the main urban area of Beijing from^(2)016 to 2021 based on the vegetation information from Sentinel-2 data,and further combined with the PT-JPLim model,the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs),and the analytical WUE(Water Use Efficiency)model to simulate the monthly ET,ET partitioning(transpiration E t,soil evaporation E b,interception evaporation E i,and impervious surface evaporation E u),gross primary productivity(GPP),carbon storage,and ecosystem WUE for the main urban area of Beijing at a spatial resolution of 10 m×10 m.Larger values of vegetation index were concentrated in the western mountainous areas,and the park areas of Beijing also presented larger NDVI(Normalized Differnce Vegetation Index)with a maximum value of 0.65.The annual mean ET in the main urban area of Beijing is 497 mm,with the highest ET in the western mountainous area,exceeding 1000 mm.ET increases with the increase of LAI(Leaf Area Index)and EVI(Enhanced Vegetation Index).Increases in NDVI,LAI,and EVI were observed at a rate of 0.0048,0.016 m^(2)·m-2,and 0.0047 per year,respectively,from^(2)016 to 2021.The regional average E t was 141.51 mm,E i was 50.77 mm,and E b was 272 mm.E u was distributed only on impervious surfaces of building sites,and E u ET on impervious surfaces was 18.2%.The areas with higher carbon storage were mainly distributed in the western mountains,which had relatively high elevation,high vegetation cover,and high values of total carbon storage density exceeding 5 t hm^(2).The mean value of GPP in the study area was 2.7 g·m^(-2)·d^(-1),and the annual mean WUE was 0.63 g·mm^(-1).There was a significant negative correlation betwe

关 键 词：城市化 生态系统 蒸散发 北京市 水分利用效率 

分 类 号：P339[天文地球—水文科学]