彭冲涧小流域蒸发散变化及其影响因素分析  

Evapotranspiration Variation and Its Drivinging Factors in Pengchongjian Small Watershed,Jiangxi,China

作　　者：盛菲 刘士余[1,2] 时建国 卢静媛 杨敏 李俊 SHENG Fei;LIU Shiyu;SHI Jianguo;LU Jingyuan;YANG Min;LI Jun(College of Land Resources and Environment,Jiangxi Agricultural University,Nanchang 330045,China;Key Laboratory of Poyang Lake Watershed Agricultural Resources and Ecology of Jiangxi Province,Nanchang 330045,China;Jiangxi Bureau of Hydrology,Nanchang 330000,China)

机构地区：[1]江西农业大学国土资源与环境学院,江西南昌330045 [2]江西省鄱阳湖流域农业资源与生态重点实验室,江西南昌330045 [3]江西省水文局,江西南昌330000

出　　处：《江西农业大学学报》2021年第1期223-234,共12页Acta Agriculturae Universitatis Jiangxiensis

基　　金：国家自然科学基金项目(31960331)。

摘　　要：【目的】蒸发散是森林流域水量平衡的重要组成部分,深入探究流域蒸发散的变化特征及影响因素,对流域水资源的合理配置具有重要意义。【方法】以南方红壤区的彭冲涧小流域为研究对象,基于1983—2014年的气象、水文观测资料,运用Mann-Kendall检验法、小波分析等探讨了1983—2014年蒸发散及其影响因素的变化特征,利用累积距平法将蒸发散时间序列划分为1983—2003年和2004—2014年2个时段,并通过灰色关联度分析得到了1983—2014年、1983—2003年、2004—2014年3个时段的年尺度上和1983—2014年的季节尺度上降雨量、气温、风速、NDVI、饱和水汽压差、潜在蒸发散和日照时数这7个因素对蒸发散影响的排序。【结果】(1)1983—2014年流域降雨量和径流深在季节和年尺度上变化趋势均不显著,降雨量仅在冬季呈上升趋势,而径流深在季节、年尺度上均呈下降趋势。(2)蒸发散仅在春季呈显著上升趋势,并在2003年发生突变,突变后蒸发散的年内分配更为均匀;年蒸发散主要存在3~7年、9~15年、18~26年这3种时间尺度的周期变化,其变化的4个主周期依次为4,6,25,12年。(3)年尺度上,蒸发散的影响因素气温、NDVI、饱和水汽压差、日照时数均呈上升趋势,而风速、潜在蒸发散呈下降趋势;除NDVI的变化趋势显著、潜在蒸发散不显著外,其它因素的变化均为极显著。季节尺度上,气温、NDVI、饱和水汽压差、日照时数均呈上升趋势,风速呈下降趋势,潜在蒸发散仅在春季呈上升趋势;除气温、日照时数在夏季和冬季,潜在蒸发散在4个季节,风速在春季和夏季,NDVI在冬季的变化趋势不显著外,上述6个因素在其它季节均表现为显著或极显著变化。(4)年尺度上,1983—2014年和1983—2003年蒸发散影响因素的灰色关联度均为风速最大,而2004—2014年蒸发散与NDVI的关联度最大;季节尺度上,1983—2014年春、夏季排序[Objective]Evapotranspiration(ET)is an important component of water budget,especially in forest watersheds.Unraveling the variation in ET and the factors influencing ET in forest watersheds is of great significance for rational allocation of water resources.[Method]In this study,the ET in a small watershed of Pengchongjian,located in a red soil region of Southern China was investigated.Based on the local hydrometeoro⁃logical data of 1983—2014,the variation characteristics of ET and its influencing factors we explored by using Mann-Kendall test and wavelet analysis,and the ET time series was divided into two periods(1983—2003,2004—2014)by cumulative anomaly method.Then seven factors potentially influencing ET were ranked,includ⁃ing precipitation,temperature,wind speed,normalized difference vegetation index(NDVI),vapor pressure defi⁃cit,potential ET and sunshine hours,on annual(1983—2003,2004—2014,and 1983—2014)and seasonal(1983—2014)scales by using grey relational analysis.[Result]The results showed that the trend of precipita⁃tion and runoff depth were not significant on the seasonal and annual scales from 1983 to 2014,and precipita⁃tion only increased in winter,while runoff depth decreased on seasonal and annual scales.The ET only showed a significant increasing trend in spring,and had a change-point in 2003.After the abrupt change,the intra-annu⁃al distribution was more uniform.Periodic variation in ET was evident on three main time scales(3-7,9-15,and 18-26 years),and the first to the fourth principal periods of ET variation occurred at 4,6,25,and 12 years.On the annual scale,the influencing factors of ET,such as temperature,NDVI,vapor pressure deficit and sunshine hours,showed an upward trend,while wind speed and potential ET showed a downward trend.Except for the sig⁃nificant trend of NDVI and insignificant trend of potential ET,the variation of other factors were extremely sig⁃nificant.On the seasonal scale,temperature,NDVI,vapor pressure deficit and sunshine hours showed an in

关 键 词：蒸发散 影响因素 灰色关联度 彭冲涧小流域 

分 类 号：S715[农业科学—林学]