摘要
为探讨MOD16和BESS两种蒸散产品在干旱半干旱地区的适用性,从区域尺度、逐像元尺度和不同植被类型等层面对两种蒸散进行了对比。结果表明,MOD16估算的宁夏近15a平均蒸散为264. 23mm,略高于BESS估算的259. 39mm,二者均略低于该地区的年平均降水量;空间上,MOD16在中部干旱带低估了蒸散,而在南部丘陵山区高估了蒸散;两种蒸散在像元尺度达到了极显著正相关,相关系数在0. 87-0. 95之间(P <0. 01);两种模型对不同植被类型地表蒸散的估算一致,均为林地蒸散最高,农田蒸散次之,草地蒸散最低;两种蒸散在年尺度上和年降水量序列具有较为一致的波动特征;总体来看,两种遥感蒸散产品在干旱半干旱地区的适用性较一致,均能反映出不同植被类型和地理单元的蒸散差异特征,但因模型机理不同又表现出各自的特点。
In order to explore the applicability of MOD16 and BESS in arid and semi-arid regions,the two evapotranspiration products were compared from the perspective of the region scale,pixel-by-pixel scale and types of vegetation.The results showed that the average ET of Ningxia province in the past 15 years estimated by MOD16 is 264.23 mm,which is slightly higher than the 259.39 mm evaluated by BESS.These two kinds of ET are less than the annual average precipitation of Ningxia province at the same time.From the perspective of spatial characteristics,MOD16 underestimates ET in the central arid zone and overestimates ET in the hilly southern area.The MOD16 and BESS ET have a significantly positive correlation in pixel scale,the correlation coefficient is between 0.87 and 0.95( P < 0.01).The estimated results of these two models for surface ET of different vegetation types are consistent with each other.The strongest ET appears in forest that followed by farmland,and the weakest appears in grassland.Both ET products have the same characteristics of fluctuation in annual scale with series of precipitation.In general,the applicability of these two kinds of remote sensing ET products in arid and semi-arid regions is more consistent,which can reflect the characteristics of ET of different vegetation types and separate geographical units.However,these two kinds of remote sensing ET products showed different characteristics due to different mechanism models.
作者
宫菲
杜灵通
刘可
朱玉果
丹杨
王乐
郑琪琪
GONG Fei;DU Lingtong;LIU Ke;ZHU Yuguo;DAN Yang;WANG Le;ZHENG Qiqi(Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China,Ningxia University ,Yinchuan 750021, China;Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China of Ministry of Education,Ningxia University, Yinchuan 750021,China;School of Agricuhure,Ningxia University ,Yinchuan 750021,China)
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2019年第1期197-202,共6页
Journal of Arid Land Resources and Environment
基金
宁夏自然科学基金(NZ16010)
国家自然科学基金(41661003)
宁夏高等学校一流学科建设(生态学)项目(NXYLXK2017B06)
中国科学院"西部之光"人才培养引进计划(XAB2017AW01)资助
关键词
蒸散
干旱半干旱地区
MODIS
气象因子
evapotranspiration
arid and semi-arid areas
MODIS
accuracy assessment
meteorological factors