摘要
【目的】基于遥感数据从区域尺度探究四川省干旱特征及其对气候因子的响应,以期揭示四川省干旱变化的动态特征和未来干旱变化的潜在机制。【方法】基于GEE(Google Earth Engine)平台提供的2001—2022年MODIS数据产品提取温度植被干旱指数(Temperature vegetation dryness index,TVDI)和蒸散发(Evapotranspiration,ET),并辅以Sen’s斜率、Hurst指数和相关分析法探究四川省2001—2022年干旱、ET时空变化特征及其对气候变化的响应。【结果】(1)22年间四川省干旱总体为川西北高原干旱程度弱于成都平原、川东盆地平原和川西南山地地区,全省以不显著减轻趋势为主。春、夏季干旱程度最小,以不显著减轻趋势为主,秋、冬两季旱情较为严重,均呈增加趋势。(2)ET总体为川西北高原小于成都平原和川东盆地平原,与TVDI的空间分布规律存在一致性。四季ET均以增加趋势为主,春季增加速率最大,冬季最小。未来一段时间内TVDI和ET可能均会出现大面积的增加趋势,但ET的持续性小于TVDI。(3)TVDI与年均降水在海拔较高的川西北高原、金沙江河谷和成都平原东部以负相关为主,与年均气温以正相关为主,与日最低气温最小值、日最低气温最大值、日最高气温最小值和最大1日降雨量以正相关为主,与日最高气温最大值和最大5日降雨量以负相关为主。ET与年均降水、年均气温、日最低气温最小值、日最高气温最小值以正相关为主,与日最低气温最大值在川西北高原表现为负相关,在川西南的攀枝花市、成都平原和川东盆地平原地区以正相关为主,与日最高气温最大值、最大1日降雨量和最大5日降雨量以负相关为主,存在显著的空间差异。【结论】四川省干旱和蒸散发时空动态存在显著的时空差异,未来均有增加趋势,且均受到气候因子(特别是极端气候)影响较大。
[Objective]The paper aimed to investigate the characteristics of drought in Sichuan province and its response to climatic factors from a regional perspective using remote sensing data,in order to reveal the dynamic characteristics of drought changes and the potential mechanisms of future drought changes in Sichuan province.[Method]The study utilized the MODIS data products available on the Google Earth Engine(GEE)platform from 2001 to 2022 to extract the Temperature Vegetation Dryness Index(TVDI)and Evapotranspiration(ET).The Sen's slope,the Hurst exponent and correlation analysis were employed to investigate the spatiotemporal variation characteristics of drought and ET in Sichuan province from 2001 to 2022,as well as their responses to climate change.[Result](i)Over the 22 years,the overall drought severity in Sichuan province was weaker in the northwestern highlands than in the Chengdu plain,eastern Sichuan basin and southwestern mountainous regions.The overall trend across the province showed no significant reduction in drought severity.The least drought severity occurred in spring and summer,which also exhibited no significant reduction trends,while autumn and winter experienced more severe drought conditions,both showing an increasing trend.(ii)ET was generally lower in the northwestern highlands compared to the Chengdu plain and eastern Sichuan basin,aligning with the spatial distribution pattern of TVDI.ET showed an increasing trend in all seasons,with the greatest increase in spring and the least in winter.In the future,both drought and ET were likely to exhibi a widespread increasing trend,though the persistence of ET was less than that of TVDI.(iii)TVDI primarily showed a negative correlation with annual precipitation at higher elevations in the northwestern highlands,Jinsha river valley,and eastern Chengdu plain,and a positive correlation with annual temperature.It also had positive correlations with minimum and maximum daily low temperatures,maximum daily high temperatures and the maximum oneday rainfall,while showing negative correlations with the maximum daily high temperature and maximum five-day rainfall.ET was mainly positively correlated with annual precipitation,annual temperature,minimum daily low temperatures and minimum daily high temperatures.In the northwestern highlands,it was negatively correlated with maximum daily low temperatures,but positively correlated in Panzhihua city in southwestern Sichuan,Chengdu plain and eastern Sichuan basin.ET exhibited negative correlations with maximum daily high temperatures,maximum one-day rainfall and maximum five-day rainfall,with significant spatial variations.[Conclusion]The spatiotemporal dynamics of drought and evapotranspiration in Sichuan province shows significant temporal and spatial differences,with both expected to increase in the future,heavily influenced by climate factors(especially extreme climate events).
作者
杨文民
曹琛
陈响
YANG Wen-min;CAO Chen;CHEN Xiang(School of Architecture and Engineering,Puyang Vocational and Technical College,Puyang,Henan 457000,China;College of Construction Engineering,Jilin University,Changchun 130012,China;Puyang Hydrological and Water Resources Monitoring and Reporting Center,Puyang,Henan 457000,China)
出处
《西南农业学报》
北大核心
2025年第6期1346-1356,共11页
Southwest China Journal of Agricultural Sciences
基金
国家自然科学基金项目(41807227)。
关键词
干旱指数
蒸散发
气候
四川省
TVDI
Evaporating
Climate
Sichuan province
