在伊比利亚半岛使用250米的MODIS EVI2数据分析了长期的时空地表表现学模式
Jose A Caparros-Santiago1, Victor Rodriguez-Galiano1
1Department of Physical Geography and Regional Geographic Analysis, Universidad de Sevilla, 41004 Seville, Spain.
The Science of the total environment
|September 23, 2024
概括
这项研究使用卫星数据在21年内绘制了伊比利亚半岛陆地表面现象的地图. 结果显示生长季节开始和结束的区域差异,使用更高分辨率图像进行潜在的改进.
科学领域:
- 生态与环境科学 生态与环境科学
- 遥感 遥感 遥感 遥感
- 气候变化的影响 气候变化的影响
背景情况:
- 伊比利亚半岛的生态系统极易受到全球变暖的影响,影响其服务.
- 这些生态系统中的季节变化和陆地表面现象学 (LSP) 仍未得到充分研究.
- 了解现象变化对于预测生态系统对气候变化的反应至关重要.
研究的目的:
- 描述2001-2021年伊比利亚半岛的陆地表面现象学 (LSP) 模式.
- 分析三个关键的现象:季节开始 (SOS),季节结束 (EOS) 和季节长度 (LOS).
- 为了比较卫星衍生的现象测量与现场的人类现象观测.
主要方法:
- 利用了21年来MOD09Q1 (250m分辨率) 的8天复合EVI2 (双带增强植被指数) 数据.
- 为伊比利亚的生态系统计算了SOS,EOS和LOS.
- 采用皮尔森的相关性,p值和绝对差异来评估表观-表相一致性.
主要成果:
- 通常在阿尔卑斯山和大西洋地区观察到较晚的SOS和EOS日期;SOS在3月至4月,EOS在10月至12月.
- 自然植被类型表现出类似的现象学动态,在地中海草原,草原和灌木中出现更早的现象学日期.
- 在大西洋植被中发现了SOS和叶子展开之间强烈的相关性,但在地中海落叶类型中发现的相关性较弱;EOS的一致性不清楚.
结论:
- 陆地表面现象学在伊比利亚生物地理区域和植被类型之间有很大差异.
- 卫星衍生的表观通常与现场观测一致,特别是在大西洋植被中的春季表相.
- 建议采用更高空间分辨率的卫星数据,以提高EOS和秋季现象相的一致性,特别是在异质的地中海生态系统中.
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