Using Remote Sensing to Identify Drivers behind Spatial Patterns in the Bio-physical Properties of a Saltmarsh Pioneer
Using Remote Sensing to Identify Drivers behind Spatial Patterns in the Bio-physical Properties of a Saltmarsh Pioneer
复制标题
利用遥感识别盐沼先驱生物物理特性空间模式背后的驱动因素
作者：
B. Oteman;E. Morris;G. Peralta;T. Bouma;D. Wal
最近，盐沼的空间组织被证明包含有关系统弹性的重要信息。然而，在盐沼中，人们对什么塑造过程调节土壤或植被特性的空间模式仍然知之甚少，而这些特性可以在表面反射信号中检测到。在本案例研究中，我们比较了四种主要塑造过程对表面反射率的影响：洪水持续时间、波浪强迫、竞争和小溪形成。我们将 ProSail 模型应用于一种先锋盐沼物种（大米草），以确定这些过程通过哪些植被和土壤特性影响反射率，并使用叶子和冠层尺度的原位反射率数据以及冠层尺度的卫星数据来确定这种盐沼先锋在春季的生物物理特征的空间模式。我们的研究结果表明，所研究的盐沼先锋区的空间格局主要是由洪水持续时间的影响引起的。洪水持续时间对冠层特性变化的解释是波浪强迫、竞争或溪流影响的三倍多。它特别通过冠层特性影响空间模式，尤其是叶面积指数，而叶子特性似乎对反射率的影响相对较小。
Recently, spatial organization in salt marshes was shown to contain vital information on system resilience. However, in salt marshes, it remains poorly understood what shaping processes regulate spatial patterns in soil or vegetation properties that can be detected in the surface reflectance signal. In this case study we compared the effect on surface reflectance of four major shaping processes: Flooding duration, wave forcing, competition, and creek formation. We applied the ProSail model to a pioneering salt marsh species (Spartina anglica) to identify through which vegetation and soil properties these processes affected reflectance, and used in situ reflectance data at the leaf and canopy scale and satellite data on the canopy scale to identify the spatial patterns in the biophysical characteristics of this salt marsh pioneer in spring. Our results suggest that the spatial patterns in the pioneer zone of the studied salt marsh are mainly caused by the effect of flood duration. Flood duration explained over three times as much of the variation in canopy properties as wave forcing, competition, or creek influence. It particularly affects spatial patterns through canopy properties, especially the leaf area index, while leaf characteristics appear to have a relatively minor effect on reflectance.