Change trend and attribution analysis of leaf area index in the East African Plateau from 1982 to 2020

Ying Yong Sheng Tai Xue Bao. 2024 Sep 18;35(9):2561-2570. doi: 10.13287/j.1001-9332.202409.021.

Abstract

The ecosystems on the East African Plateau are crucial for maintaining the biodiversity, water resource balance, and ecological equilibrium of the African continent. However, the spatiotemporal variations of vegetation and the driving factors remain unclear. We analyzed leaf area index (LAI) change trends in the East African Plateau based on the GIMMS LAI4g dataset and further conducted attribution analysis combining temperature and precipitation data, as well as 10 Dynamic Global Vegetation Models (DGVMs) in TRNEDY v9. The results showed that LAI of the East African Plateau had a modest change trend from 1982 to 1999 (2.5×10-3 m2·m-2·a-1), but significantly increased from 2000 to 2020 (5.2×10-3 m2·m-2·a-1), which was 2.1 times faster than that during 1982-1999. Temperature and precipitation had weak correlations with LAI from 1982 to 1999, but showed significant correlations from 2000 to 2020. The DGVMs demonstrated consistent attribution results, with temperature and precipitation contributing significantly more to the LAI variations from 2000 to 2020 compared to the period from 1982 to 1999. The results highlighted the key role of climate change in driving vegetation greening on the East African Plateau during 2000-2020, which could provide important evidence for ecological conservation and sustainable development strategies in the region.

东非高原的生态系统对于维持非洲大陆的生物多样性、水资源平衡和生态平衡至关重要,然而该地区植被的时空变化及其驱动因素尚不清楚。本研究基于GIMMS LAI4g数据集检测东非高原的叶面积指数(LAI)的变化趋势,并结合气温和降水数据、TRNEDY v9中10个动态植被模型(DGVM)数据进行归因分析。结果表明: 东非高原的LAI在1982—1999年间变化趋势平缓(2.5×10-3 m2·m-2·a-1),而在2000—2020年显著上升(5.2×10-3 m2·m-2·a-1),是1982—1999年间的2.1倍;气温和降水的变化在1982—1999年间与LAI的相关性较弱,在2000—2020年间与LAI变化显著相关;不同DGVM显示出一致的归因结果,表现为气温和降水的变化对2000—2020年间LAI趋势的贡献明显高于1982—1999年间。研究表明了2000—2020年间气候变化在推动东非高原植被显著变绿中的关键作用,可为该地区的生态保护和可持续发展策略提供重要依据。.

Keywords: East African Plateau; climate change; leaf area index; vegetation change.

MeSH terms

  • Africa, Eastern
  • Altitude
  • Climate Change*
  • Conservation of Natural Resources / trends
  • Ecosystem*
  • Plant Leaves* / growth & development
  • Rain
  • Temperature