摘要
随着气候变化与人类活动的加剧,中国干旱频繁发生且影响不断加剧,探索干旱对植被生长的影响对研究生态系统如何应对干旱具有重要意义。基于中国1982—2015年改进帕尔默干旱指数(scPDSI)与归一化植被指数(NDVI)数据,分析植被对干旱的响应规律及敏感性。结果表明:1)在中国西北地区、内蒙古地区、东部地区及青藏高原南部地区,短滞时(1-3月)scPDSI与NDVI的相关性较大(Rmax>0.4),南方湿润地区降水充沛,植被对干旱的响应不敏感(Rmax<0.3),其生长主要受能量因素控制;2)年均水分盈亏量、降水量、日照时数和气温对植被与干旱的关系影响较大,其中年均水分盈亏量是主要控制因子;3)不同植被类型对干旱的敏感性有较大差异,敏感排序为草地>林地>耕地。研究结果可为中国不同区域干旱对植被生长影响评估提供科学依据。
Drought is a natural hazard caused by long-term precipitation deficiency and high evaporation resulted from high temperature, which is among the most common disasters around the world. In recent decades, with the intensification of climate change and human activities, drought occurrence is becoming more frequent in China, causing negative impacts on agricultural production, ecological environment and social economy. Therefore, it is significant to explore the impact of drought on vegetation for agricultural production and healthy development of ecological systems. In this paper, the response and sensitivity of vegetation to drought in different climatic zones in China were analyzed, and the effects of different climatic factors, including water balance(precipitation-potential evapotranspiration), annual precipitation, mean temperature and sunshine hours, on the relationship between different vegetation types including forestland, grassland and cultivated land and drought were explored, so as to reveal the response mechanism of ecological vegetation to drought from a macro perspective. Using the self-calibrating Palmer drought severity index(scPDSI) and normalized difference vegetation index(NDVI) data for the period of 1982-2015, the response rule and sensitivity of different types of vegetation to drought were analyzed by applying time-delay correlation method, and the influence of various climate factors on the relationship between vegetation and drought was analyzed by applying linear regression method. The results of the research showed that in northwest China, Inner Mongolia, north China plain and southern Qinghai-Tibet plateau, the correlation of shorter lag time scPDSI(1-3 months) and NDVI was close(Rmax>0.4), which indicated that vegetation growth was more sensitive to drought in these regions and that vegetation biomass were influenced mainly by the spatiotemporal characteristics of the water availability. In the humid areas of south China, including the middle and lower reaches of the Yangtze River and
作者
张更喜
粟晓玲
郝丽娜
吴海江
Zhang Gengxi;Su Xiaoling;Hao Lina;Wu Haijiang(College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,China;Key Laboratory for Agricultural Soil and Water Engineering in Arid Area of Ministry of Education,Northwest A&F University,Yangling 712100,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2019年第20期145-151,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(51879222)
