Scholarlink

<p>Land Surface Phenology (LSP)—the satellite-derived characterization of seasonal vegetation dynamics—is shifting under climate change across local to global scales. Yet fine-scale, ecoregion-level LSP assessments remain absent for Nepal despite its heterogeneous topography and high vulnerability to climate change. We analyzed trends of four LSP metrics: start of season (SOS), end of season (EOS), length of season (LOS), and peak of season (POS) across Nepal’s nine ecoregions using 24 years (2001–2024) of MODIS EVI data (~ 250&#xa0;m) and evaluated the topographic and climatic drivers of the observed trends. SOS advanced in temperate, subtropical, and tropical ecoregions (5.63–12.24% of pixels) but delayed in alpine and subalpine ecoregions (~ 4% of pixels). EOS delayed across eight of nine ecoregions (4.41–6.50% of pixels), LOS increased in eight ecoregions (4.69–18.18% of pixels), and POS increased universally (6.92–37.49% of pixels), with the strongest trends in lower-elevation ecoregions. Elevation exerted the dominant topographic control on LSP trends in alpine and subalpine zones by mediating thermal and snow dynamics. Conversely, slope-driven moisture redistribution dominated in subtropical and tropical zones, while temperate ecoregions showed mixed topographic control. Climatic driver analysis identified moisture availability as a key constraint, expressed through pre-monsoon evaporative demand and soil moisture limitation at lower elevations, and through snowmelt-controlled water access in alpine zones. In high-elevation ecoregions, regional climate-phenology correlations were largely overridden by local topography. These findings demonstrate that fine-scale, topography-aware analytical frameworks are essential for interpreting heterogeneous LSP responses in topographically complex mountain landscapes.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Topographic and climatic drivers of elevation-dependent land surface phenology shifts across Nepal’s ecoregions

  • 期刊论文

  • 发表日期：

    2026年4月30日

查看全文
  • Jeevan Prakash Katel,
  • Uttam Babu Shrestha,
  • Suraj Joshi

摘要

Land Surface Phenology (LSP)—the satellite-derived characterization of seasonal vegetation dynamics—is shifting under climate change across local to global scales. Yet fine-scale, ecoregion-level LSP assessments remain absent for Nepal despite its heterogeneous topography and high vulnerability to climate change. We analyzed trends of four LSP metrics: start of season (SOS), end of season (EOS), length of season (LOS), and peak of season (POS) across Nepal’s nine ecoregions using 24 years (2001–2024) of MODIS EVI data (~ 250 m) and evaluated the topographic and climatic drivers of the observed trends. SOS advanced in temperate, subtropical, and tropical ecoregions (5.63–12.24% of pixels) but delayed in alpine and subalpine ecoregions (~ 4% of pixels). EOS delayed across eight of nine ecoregions (4.41–6.50% of pixels), LOS increased in eight ecoregions (4.69–18.18% of pixels), and POS increased universally (6.92–37.49% of pixels), with the strongest trends in lower-elevation ecoregions. Elevation exerted the dominant topographic control on LSP trends in alpine and subalpine zones by mediating thermal and snow dynamics. Conversely, slope-driven moisture redistribution dominated in subtropical and tropical zones, while temperate ecoregions showed mixed topographic control. Climatic driver analysis identified moisture availability as a key constraint, expressed through pre-monsoon evaporative demand and soil moisture limitation at lower elevations, and through snowmelt-controlled water access in alpine zones. In high-elevation ecoregions, regional climate-phenology correlations were largely overridden by local topography. These findings demonstrate that fine-scale, topography-aware analytical frameworks are essential for interpreting heterogeneous LSP responses in topographically complex mountain landscapes.