蒙古国冬春季气候非对称变暖及其对植被返青期和春季NDVI的影响  

Asymmetrical warming in winter and spring and its effect on start of growing season and spring NDVI in Mongolia

作　　者：张港栋 包刚[1,2] 黄晓君[1,2] 元志辉 温都日娜[1,2] ZHANG Gangdong;BAO Gang;HUANG Xiaojun;YUAN Zhihui;WEN Durina(College of Geographical Science,Inner Mongolia Normal University,Hohhot 010022,Inner Mongolia,China;Inner Mongolia Key Laboratory of Remote Sensing&Geography Information System,Hohhot 010022,Inner Mongolia,China)

机构地区：[1]内蒙古师范大学地理科学学院,内蒙古呼和浩特010022 [2]内蒙古师范大学内蒙古自治区遥感与地理信息系统重点实验室,内蒙古呼和浩特010022

出　　处：《干旱区地理》2023年第8期1238-1249,共12页Arid Land Geography

基　　金：内蒙古自治区科技计划项目(2021GG0183);内蒙古高校青年科技英才支持计划项目(NJYT22030);内蒙古自治区自然科学基金项目(2021MS04014)资助。

摘　　要：基于2001—2020年NDVI和EVI两种遥感植被指数及蒙古国60个气象站点的气温和降水数据,利用累积植被指数的Logistic曲线曲率极值法和动态阈值法提取蒙古国植被返青期,并结合偏相关分析方法探讨二者与冬春季昼夜气温非对称变化之间的关系。结果表明:(1)近20 a来,最高气温在冬春季的变暖速率分别为0.07℃·a^(-1)、0.15℃·a^(-1)(P<0.05,R^(2)=0.33),最低气温在冬春季的变化速率分别为-0.01℃·a^(-1)、0.04℃·a^(-1),冬春季气温日较差的变化速率分别为0.08℃·a^(-1)、0.11℃·a^(-1)(P<0.05,R^(2)=0.52),存在明显的季节性差异。(2)蒙古国植被返青期对冬春季气候变暖的季节性响应是非对称的,冬季最高气温和气温日较差的影响大,而春季则是最低气温影响大,且均表现为负相关。(3)蒙古国气候变暖对植被NDVI产生的非对称影响主要表现在春季,即春季最高气温和气温日较差对植被NDVI主要表现为负相关,而春季最低气温对植被NDVI主要表现为正相关。研究结果可为进一步了解全球气候变暖背景下植被春季物候及植被后期生长的季节性影响提供重要参考价值。Based on the normalized difference vegetation index(NDVI)and enhanced vegetation index obtained from remote sensing and on temperature and precipitation data from 60 meteorological stations in Mongolia from 2001 to 2020,the logistic curve method and dynamic threshold method of the cumulative vegetation index were used to extract the vegetation green-up period in Mongolia.Partial correlation analysis was used to explore the relationship between the vegetation green-up period and the asymmetric changes in diurnal temperature in winter and spring.The results were as follows:(1)In the past 20 years,the warming rates for highest winter and spring temperatures were 0.07℃·a^(−1) and 0.15℃·a^(−1)(P<0.05,R^(2)=0.33)respectively,while the change rates of the lowest winter and spring temperatures were−0.01℃·a^(−1) and 0.04℃·a^(−1) respectively.The change rate of the winter and spring diurnal temperature ranges were 0.08℃·a^(−1) and 0.11℃·a^(−1)(P<0.05,R^(2)=0.52)respectively,showing clear seasonal differences.(2)The seasonal response of the start of the growing season to winter and spring climate warming is asymmetric,with the highest temperature and diurnal temperature range having a greater impact in winter,while the lowest temperature has a greater impact in spring;both show negative correlations.(3)The asymmetric impact of climate warming on NDVI in Mongolia is mainly manifested in spring.The highest spring temperature and spring diurnal temperature range have a mainly negative correlation with NDVI,while the lowest spring temperature has a mainly positive correlation with NDVI.This study provides an important reference in the study of the seasonal effects of climate warming on vegetation phenology and late-stage growth.

关 键 词：返青期 春季NDVI 非对称变化 气温日较差 蒙古国 

分 类 号：Q948[生物学—植物学] P461[天文地球—大气科学及气象学]