地理学报 ›› 2021, Vol. 76 ›› Issue (5): 1231-1244.doi: 10.11821/dlxb202105014

• 气候变化与地表过程 • 上一篇    下一篇

2000—2015年中蒙俄经济走廊东段冻土时空变化及植被响应

刘侦海1(), 王绍强1,2,3, 陈斌2()   

  1. 1.中国地质大学(武汉)地理与信息工程学院,武汉 430074
    2.中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室,北京 100101
    3.中国科学院大学资源与环境学院,北京 100049
  • 收稿日期:2020-08-09 修回日期:2021-04-18 出版日期:2021-05-25 发布日期:2021-07-25
  • 通讯作者: 陈斌(1981-), 男, 福建福州人, 助理研究员, 主要从事生态系统生态学相关研究。E-mail: chenbin@igsnrr.ac.cn
  • 作者简介:刘侦海(1996-), 男, 山东菏泽人, 硕士生, 主要从事生态系统变化与生态模拟相关研究。E-mail: lzhzlw@cug.edu.cn
  • 基金资助:
    中国科学院战略性先导科技专项资助(XDA20030203);中国地质大学(武汉)科研启动基金资助项目(162301192642)

Spatial and temporal variations of frozen ground and its vegetation response in the eastern segment of China-Mongolia-Russia economic corridor from 2000 to 2015

LIU Zhenhai1(), WANG Shaoqiang1,2,3, CHEN Bin2()   

  1. 1. School of Geography and Information Engineering, China University of Geosciences, Wuhan 430074, China
    2. Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
    3. College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2020-08-09 Revised:2021-04-18 Published:2021-05-25 Online:2021-07-25
  • Supported by:
    The Science and Technology Strategic Pilot of the Chinese Academy of Sciences(XDA20030203);Scientific Research Foundation of China University of Geosciences(162301192642)

摘要:

中蒙俄经济走廊东段位于欧亚大陆多年冻土区东南缘及森林线南界接近区,冻土及生态环境脆弱。本文基于MERRA-Land陆面模式离线运行产品分析了中蒙俄经济走廊东段2000—2015年间冻土冻融的时空变化模式,以及冻土变化对返青期和全年不同阶段植被生长状态的影响。研究表明:2000—2015年间研究区多年冻土及季节冻土均持续退化,时间上主要表现为冻土提前解冻、延迟冻结;空间上主要表现为多年冻土南界的多年冻土退化和季节冻土下限抬升,及连续多年冻土南界的活动层加厚。解冻始日是森林地区植被返青的主控要素,林下冻土解冻对土壤含水量的增加及沼泽湿地的隔热蓄水功能影响了森林地区植被的生长。但随着多年冻土南界森林及林下泥炭地演替为草甸和农田,多年冻土退化,进一步促进林下沼泽湿地的消失。探讨冻土退化与生态环境之间的协同关系,有助于识别气候变暖和人类活动叠加影响下的冻土退化脆弱区以及生态环境敏感区。

关键词: 中蒙俄经济走廊东段, 冻土退化, 植被生长, 灰色关联分析

Abstract:

The eastern segment of the China-Mongolia-Russia economic corridor is situated in the overlap region of the southeast margin of Eurasia permafrost region and the southern border of the tree line, where fragile frozen ground and ecosystems have been maintained. In this study, we analyzed the spatiotemporal distribution and annual change of frozen ground, leaf area index (LAI), and the vegetation green-up data in the eastern China-Mongolia-Russia economic corridor from 2000 to 2015 based on the MERRA-Land data product, GLOBMAP LAI, and MODIS EVI dataset. The main controlling environmental factors of the green-up date and the status of vegetation growth in the different periods over a year were calculated by grey correlation analysis, and then the response of vegetation growth in typical areas to the freezing-thawing changes of the frozen ground was analyzed. Some conclusions can be drawn as follows. (1) In the past 16 years, permafrost and seasonal frost in the eastern China-Mongolia-Russia economic corridor was persistently and significantly degraded, which was mainly reflected by the early thawing and delayed freezing of the frozen ground in time, and manifested as the disappearance of permafrost and the uplift of the lower limit of seasonal frost in the southern isolated permafrost, and the thickening of the active layer in the southern continuous permafrost in space. (2) In about 48% of forest areas, the onset day of frozen ground melting is the main factor affecting the start of vegetation greening season. The growth situation of vegetation in forest areas is altered by the soil water from thawing frozen ground and the hydrothermal mechanisms of peatland. (3) With the transition from forest and peatland to meadow or farmland, the frozen ground degrades and in turn further facilitates the fade of peatland. Exploring the synergetic relationship between the degradation of frozen ground and the ecological environment is helpful to identify the vulnerable regions of degrading frozen ground and the sensitive regions of the ecological environment under the influence of climate warming and human activities.

Key words: eastern China-Mongolia-Russia economic corridor, ground freeze-thawing process, vegetation growth, gray correlation analysis