植物生态学报 ›› 2023, Vol. 47 ›› Issue (10): 1375-1385.DOI: 10.17521/cjpe.2022.0474

• 研究论文 • 上一篇    下一篇

亚洲旱区草地NDVI对气候变化的响应及滞后效应

缪丽娟1,*(), 张宇阳1, 揣小伟2, 包刚3, 何昱1, 朱敬雯4   

  1. 1南京信息工程大学地理科学学院, 南京 210044
    2南京大学地理与海洋科学学院, 南京 210023
    3内蒙古师范大学地理科学学院, 呼和浩特 010010
    4南京信息工程大学长望学院, 南京 210044
  • 收稿日期:2022-11-23 接受日期:2023-04-06 出版日期:2023-10-20 发布日期:2023-05-08
  • 通讯作者: * E-mail: miaolijuan1111@gmail.com
  • 基金资助:
    国家自然科学基金(42101295);江苏省自然科学基金(BK20210657);江苏省高等学校自然科学研究项目(21KJB170003);国家重点研发计划(2019YFC1510200)

Effects of climatic factors and their time-lag on grassland NDVI in Asian drylands

MIAO Li-Juan1,*(), ZHANG Yu-Yang1, CHUAI Xiao-Wei2, BAO Gang3, HE Yu1, ZHU Jing-Wen4   

  1. 1School of Geographical Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China
    2School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
    3College of Geographical Science, Inner Mongolia Normal University, Hohhot 010010, China
    4Changwang School of Honors, Nanjing University of Information Science and Technology, Nanjing 210044, China
  • Received:2022-11-23 Accepted:2023-04-06 Online:2023-10-20 Published:2023-05-08
  • Supported by:
    National Natural Science Foundation of China(42101295);Natural Science Foundation of Jiangsu Province(BK20210657);Natural Science Research Project for Higher Education Institutions in Jiangsu Province(21KJB170003);National Key R&D Program of China(2019YFC1510200)

摘要:

随着全球变暖和人类活动加剧, 全球干旱区进一步扩张。干旱区植被生态系统的脆弱性和敏感性增强。因此, 探究干旱区植被长势对气候变化的响应机制及滞后效应成为了当前研究的热点。该研究基于中分辨率成像光谱仪(MODIS)提供的归一化植被指数(NDVI)资料、英国东英格利亚大学气候研究所提供的逐月网格化CRU TS4.05气候资料和干旱指数资料、ERA5 (ECMWF全球气候的第五代大气再分析资料)提供的太阳辐射资料和欧洲航天局全球基本气候变化监测项目提供的土壤水分资料, 借助于窗口交叉相关法和线性回归法, 探究了2001-2020年亚洲旱区草地NDVI对气候变化的响应及滞后效应。研究发现: 1)草地NDVI对当月平均气温和降水总量的响应最为强烈, 对太阳辐射和土壤水分则存在显著的滞后响应。具体表现为草地NDVI对太阳辐射和土壤水分的响应存在1个月的滞后; 2)草地NDVI与各气候要素响应的滞后时间在空间分布上较不均匀, 在亚洲旱区的东部和西部存在明显差异; 3)草地NDVI与自矫正帕默尔干旱指数间不存在显著的滞后效应; 4)海拔在一定程度上影响了亚洲旱区草地NDVI与各要素的响应关系。

关键词: 草地, 影响要素, 归一化植被指数, 滞后效应, 亚洲旱区

Abstract:

Aims Along with intensified climatic warming and human activities, global arid areas have expanded in an unprecedented rate during the past decades. Dryland ecosystems have witnessed increased vulnerability and sensitivity to climate change. Exploring the time lag effect of climate change on dryland vegetation growth is becoming an important research highlight in current global change related studies.

Methods In this study, we synthesized the normalized difference vegetation index (NDVI) from Moderate- resolution Imaging Spectroradiometer (MODIS), the monthly gridded CRU TS4.05 (Climatic Research Unit Time-Series version 4.05) climate and drought information developed by the University of East Anglia, solar radiation information from ERA5 (ECMWF’s Fifth Generation Atmospheric Reanalysis of the Global Climate) and soil moisture information from the European Space Agency (ESA) Climate Change Initiative program (CCI). These data were designed to investigate the effects of climatic factors and their time-lag on grassland NDVI in Asian grasslands from 2001 to 2020. This analysis was conducted based on the window cross-correlation and one-dimensional linear regression.

Important findings Our study revealed that: 1) The grassland NDVI responded strongly to average temperature and total precipitation when there was no lag, but expressed a lag response to solar radiation and soil moisture (1-month). 2) The spatial distributions of the lag response of grassland NDVI to climate change were nonuniform, with significant differences observed between the western and eastern Asian grasslands. 3) We did not detect any apparent time-lag effects on interactions between grassland NDVI and self-calibrating Palmer Drought Index. 4) We argue that altitude could partly modulate the response of grassland NDVI to climatic variables in the grassland of Asian drylands.

Key words: grassland, influencing determinant, normalized difference vegetation index (NDVI), lag effect, Asian drylands