摘要
【目的】阐明2000—2020年银川市地表蒸散量变化及其主要影响因素,为以水定市、以水定林提供理论依据。【方法】基于MODIS蒸散产品MOD16,气温、降水量和归一化植被指数(NDVI),运用slope线性趋势、相关分析等方法,并采用MOD16A3数据进行作物缺水指数的计算,对银川市2000—2020年蒸散量时空变化特征、不同土地利用类型蒸散量差异及其影响因素进行分析。【结果】(1)2000—2020年银川市蒸散量在201.2~344.2 mm之间,多年均值为273.4 mm;在空间分布上,整体上呈围绕建成区的中部区域较高,西部贺兰山区域和东部区域较低的分布特征。(2)2000—2020年银川市蒸散量呈增加趋势,倾向率为5.093 mm/a,蒸散量增加的区域面积占比最高,为88.30%,可见银川市大部分区域蒸散量变化趋势是增加的,显著增加的区域主要分布在围绕建成区的部分中部区域。蒸散量减少的区域面积占比为2.44%,年蒸散量基本不变的区域面积占比为9.26%。(3)与2000年相比,2020年的耕地、林地、草地、灌木地、湿地、水体、人造地表、裸地的相对变化率为−6.73%、0.33%、−8.34%、−14.87%、21.95%、9.05%、230.45%、−2.08%。银川市蒸散量空间分布受土地利用类型影响显著,多年平均蒸散量由大到小依次为耕地(322.9 mm)、水体(268.5 mm)、人造地表(256.9 mm)、林地(240.0 mm)、湿地(220.3 mm)、灌木地(216.7 mm)、草地(201.9 mm)、裸地(196.4 mm)。(4)对银川市2000—2020年蒸散量与气温、降水量、NDVI(2000—2019年)的相关分析表明,银川市蒸散量与气温、降水量和NDVI均呈显著正相关。【结论】2000—2020年,气温、降水量、NDVI都是影响银川市年均蒸散量上升的驱动因素,其中NDVI是最主要影响因子。本研究以期为银川市水资源的合理高效利用,银川市生态需水量研究和生态环境规划提供理论支撑。
[Objective]This paper aims to elucidate the change of surface evapotranspiration and its main influencing factors in Yinchuan City of northwestern China in 2000−2020,and provide theoretical basis for determining cities and forests based on water.[Method]Based on MODIS evpotranspiration product MOD16,temperature,precipitation,normalized vegetation index(NDVI),slope linear trend and correlation analysis methods were used to calculate crop water stress index by MOD16A3 data.The spatio-temporal variation characteristics of evapotranspiration in Yinchuan City from 2000 to 2020,the difference of evapotranspiration in different land use types and its influencing factors were analyzed.[Result](1)From 2000 to 2020,evapotranspiration in Yinchuan City ranged from 201.2 to 344.2 mm,with an annual average of 273.4 mm.In terms of spatial distribution,the central region around the built-up area was higher,while the western Helan Mountain region and the eastern region were lower.(2)From 2000 to 2020,the evapotranspiration in Yinchuan City showed an increasing trend,with a tendency rate of 5.093 mm/year,and the area with increasing evapotranspiration accounted for the highest proportion(88.30%).It can be seen that the changing trend of evapotranspiration in most regions of Yinchuan City was increasing,and the significant increase area was mainly distributed in the central area around the built-up area.The area of evapotranspiration decreased was 2.44%,and the area of annual evapotranspiration basically remained unchanged was 9.26%.(3)Compared with 2000,the relative change rates of cultivated land,woodland,grassland,shrub land,wetland,water body,artificial surface and bare land in 2020 were−6.73%,0.33%,−8.34%,−14.87%,21.95%,9.05%,230.45%and−2.08%,respectively.The spatial distribution of evapotranspiration in Yinchuan City was significantly affected by land use type.The average evapotranspiration was cultivated land(322.9 mm),water body(268.5 mm),artificial surface(256.9 mm),forest land(240 mm),wetland(220.3 mm),shrub land(216.7 mm),grassland(201.9 mm)and bare land(196.4 mm)in descending order.(4)The correlation analysis of evapotranspiration with temperature,precipitation and NDVI(2000−2019)in Yinchuan City from 2000 to 2020 showed that evapotranspiration was significantly positively correlated with temperature,precipitation and NDVI.[Conclusion]It can be seen that from 2000 to 2020,temperature,precipitation and NDVI are all driving factors affecting the increase of annual evapotranspiration in Yinchuan City,and NDVI is the most important factor.This study is expected to provide theoretical support for the rational and efficient utilization of water resources in Yinchuan City and better research on ecological water demand and ecological environment planning in Yinchuan City of northwestern China.
作者
宋硕
赵婉凝
李少然
王亚飞
岳天泽
贾黎明
刘虎
Song Shuo;Zhao Wanning;Li Shaoran;Wang Yafei;Yue Tianze;Jia Liming;Liu Hu(Key Laboratory of Forest Cultivation and Protection of Ministry of Education,Beijing Forestry University,Beijing 100083,China;Experimental Teaching Center of Forestry,Beijing Forestry University,Beijing 100083,China;Zhongshan Park,Yinchuan 750000,Ningxia,China)
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2024年第7期18-26,共9页
Journal of Beijing Forestry University
基金
宁夏回族自治区重点研发计划(2019BFG02024)。
