干旱区研究 ›› 2024, Vol. 41 ›› Issue (1): 147-156.doi: 10.13866/j.azr.2024.01.14

• 生态与环境 • 上一篇    下一篇

1990—2020年黄土高原典型县域植被覆盖变化及影响因素

赵雨琪(),魏天兴()   

  1. 北京林业大学水土保持学院,水土保持国家林业局重点实验室,林业生态工程教育部工程研究中心,山西吉县森林生态系统国家野外科学观测研究站,北京 100083
  • 收稿日期:2023-07-05 修回日期:2023-08-21 出版日期:2024-01-15 发布日期:2024-01-24
  • 通讯作者: 魏天兴. E-mail: weitx@bjfu.edu.cn
  • 作者简介:赵雨琪(1999-),女,硕士研究生,主要从事生态环境地理研究. E-mail: zyq0837@bjfu.edu.cn
  • 基金资助:
    “十四五”国家重点研发计划(2022YFF1300401)

Changes in vegetation cover and influencing factors in typical counties of the Loess Plateau from 1990 to 2020

ZHAO Yuqi(),WEI Tianxing()   

  1. School of Soil and Water Conservation, Key Laboratory of State Forestry and Glassland Administration on Soil and Water Conservation, Engineering Research Center of Forestry Ecological Engineering of Ministry of Education, Jixian National Forest Ecosystem Observation and Research Station, Chinese National Ecosystem Research Network, Beijing Forestry University, Beijing 100083, China
  • Received:2023-07-05 Revised:2023-08-21 Online:2024-01-15 Published:2024-01-24

摘要:

为探究吉县近30 a植被动态演变规律及其影响因素,本研究基于Landsat影像,结合气象、土地利用、夜间灯光等数据,采用趋势分析、偏相关分析、随机森林、残差分析等方法探究吉县植被覆盖度时空变化特征及气候和人为因素对植被变化的影响。结果显示:(1)1990—2020年研究区植被覆盖度(FVC)整体呈显著上升趋势,FVC年均增长速率约为0.49%,植被质量明显改善。(2)吉县FVC具有明显的“低值-高值”交错分布的空间特征。1990—2020年FVC显著增加区占51%,FVC显著减少区占7%。(3)气候因素对部分FVC高值区和建筑区植被生长起抑制作用,对其余地区植被覆盖起促进作用。将人类活动作为全域影响因素考虑时气候和人类活动对植被动态的贡献率分别为53.43%、46.57%,将其作为局域变量时相对贡献率减少至13.07%。人类活动在特定地区如吉县中部和东部是植被退化的重要影响因素,西侧和南部的植被恢复也与之相关。研究结果可为区域生态修复工作进一步开展提供科学依据。

关键词: 植被覆盖度, Google Earth Engine, 气候变化, 人类活动, 黄土高原

Abstract:

To explore the dynamic evolution of vegetation and its influencing factors in Ji County during the last 30 years, this study used Landsat images, along with meteorological, land use, and night light data. This study adopted trend, partial correlation, random forest, and residual analysis methods to explore the temporal and spatial variation-related characteristics in vegetation coverage and the influence of the climate and human factors on the vegetation changes in the County. (1) FVC in the study area demonstrated a significant upward trend from 1990 to 2020, with an annual growth rate of 0.49%, and the vegetation quality was distinctly higher. (2) The low and high rates of FVC had an obvious staggered spatial distribution. The proportion of areas with a marked enhancement in FVC was 51%, and a remarkable reduction in FVC was 7%. (3) Temperature and precipitation inhibited vegetation growth in the FVC high-value and built-up areas, but promoted vegetation cover in others. The contribution rates of climate change and human activities to vegetation dynamics were 53.43% and 46.57%, respectively, and were considered global influencing factors. When used as local variables, the relative contribution rates were reduced to 13.07%. Human activity was an essential factor affecting vegetation degradation in certain areas, such as the central and eastern parts of Jixian County, and the vegetation restoration in the west and south. This study can provide a scientific basis for the follow-up work of regional ecological restoration.

Key words: fractional vegetation cover, Google Earth Engine, climate change, human activity, Loess Plateau