资源与生态学报(英文版)
資源與生態學報(英文版)
자원여생태학보(영문판)
JOURNAL OF RESOURCES AND ECOLOGY
2012年
1期
43-49
,共7页
张景华%姜鲁光%封志明%李鹏
張景華%薑魯光%封誌明%李鵬
장경화%강로광%봉지명%리붕
NDVI%EVI%距平植被指数%干旱监测%中国西南地区
NDVI%EVI%距平植被指數%榦旱鑑測%中國西南地區
NDVI%EVI%거평식피지수%간한감측%중국서남지구
NDVI%EVI%Vegetation Index Anomaly%drought monitoring%Southwestern China
2009年9月至2010年3月我国西南地区出现了有气象记录以来最严重的干旱,给当地的自然环境和生产、生活带来严重影响.本文利用多年MODIS/EVI数据求取距平植被指数来反映干旱对西南地区植被的影响.在此基础上,分析了西南地区植被受旱的时空格局及其可能影响因素.结果表明,我国西南地区植被受干旱影响的范围很大,超过地区总面积的50%,植被受旱程度时空差异显著.这种显著的差异除了受降水等气象因素影响外,还与不同植被类型对干旱的响应差异有很大关系.在西南地区三种主要的植被类型中,作物是最易受干旱影响的植被类型,草地次之,林地的抗旱能力最强.此外,植被干旱的空间分布与气象干旱也存在很大的差异,进一步证明了降水以外的其他因素对干旱程度的调节作用.研究证明与气象干旱指数相比,植被指数更能反映干旱的实际情况.但在使用植被指数衡量干旱影响时也要考虑到植被指数本身的局限性.
2009年9月至2010年3月我國西南地區齣現瞭有氣象記錄以來最嚴重的榦旱,給噹地的自然環境和生產、生活帶來嚴重影響.本文利用多年MODIS/EVI數據求取距平植被指數來反映榦旱對西南地區植被的影響.在此基礎上,分析瞭西南地區植被受旱的時空格跼及其可能影響因素.結果錶明,我國西南地區植被受榦旱影響的範圍很大,超過地區總麵積的50%,植被受旱程度時空差異顯著.這種顯著的差異除瞭受降水等氣象因素影響外,還與不同植被類型對榦旱的響應差異有很大關繫.在西南地區三種主要的植被類型中,作物是最易受榦旱影響的植被類型,草地次之,林地的抗旱能力最彊.此外,植被榦旱的空間分佈與氣象榦旱也存在很大的差異,進一步證明瞭降水以外的其他因素對榦旱程度的調節作用.研究證明與氣象榦旱指數相比,植被指數更能反映榦旱的實際情況.但在使用植被指數衡量榦旱影響時也要攷慮到植被指數本身的跼限性.
2009년9월지2010년3월아국서남지구출현료유기상기록이래최엄중적간한,급당지적자연배경화생산、생활대래엄중영향.본문이용다년MODIS/EVI수거구취거평식피지수래반영간한대서남지구식피적영향.재차기출상,분석료서남지구식피수한적시공격국급기가능영향인소.결과표명,아국서남지구식피수간한영향적범위흔대,초과지구총면적적50%,식피수한정도시공차이현저.저충현저적차이제료수강수등기상인소영향외,환여불동식피류형대간한적향응차이유흔대관계.재서남지구삼충주요적식피류형중,작물시최역수간한영향적식피류형,초지차지,임지적항한능력최강.차외,식피간한적공간분포여기상간한야존재흔대적차이,진일보증명료강수이외적기타인소대간한정도적조절작용.연구증명여기상간한지수상비,식피지수경능반영간한적실제정황.단재사용식피지수형량간한영향시야요고필도식피지수본신적국한성.
The severest drought on record occurred in southwestern China from September 2009 until March 2010.In order to measure the impact the drought imposed on vegetation,we developed an evaluation indicator called the Vegetation Index Anomaly (VIA) based on MODIS/EVI.The tempospatial pattern of this impact was analyzed.Given that this impact may be modulated by many factors,the responses of different vegetation types (woodland,grassland and cropland),and the spatial pattern of meteorological drought were also analyzed.Results show that more than 50% of vegetation suffered because of this drought event,but there was significant tempo-spatial variability in the range and intensity of impact.This variability may be caused by many factors.Of the three major vegetation types,cropland was the most sensitive to drought,followed by grassland and then woodland.In addition,meteorological factors (precipitation and air temperature) also played a role; however,obvious differences exist between the spatial distribution pattern of drought-stricken vegetation and that of meteorological drought,which further demonstrates the intervention of other factors besides meteorological factors.So compared to meteorological drought,the vegetation index may be more useful for measuring the actual intensity,duration and impact of drought events.The limitations of vegetation indices are also considered.