From wetlands to wetlandscapes: Remote sensing calibration of process‐based hydrological models in heterogeneous landscapes
From wetlands to wetlandscapes: Remote sensing calibration of process‐based hydrological models in heterogeneous landscapes
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DOI：
10.1002/hyp.14739
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发表时间：
2022-10
影响因子：
3.2
通讯作者：
Connor Mullen;L. Bertassello;P. Rao;M. Müller
中科院分区：
文献类型：
--
作者：
Connor Mullen;L. Bertassello;P. Rao;M. Müller
湿地是维持一系列重要生态系统服务的景观的重要组成部分。了解湿地丰富的景观--或称湿地景观--将如何在气候变化和越来越多的人为侵蚀下演变是当务之急。湿地景观具有高度的异质性，从单个仪表化湿地中推广当地建模见解以表征景观规模的动态特征一直是一个普遍的挑战。我们研究了使用卫星图像中的水域范围信息来校准基于景观尺度过程的水文模型的可能性。对北达科他州草原坑坑区(PPR)和德克萨斯州普拉亚湖(TPL)湿地景观的应用揭示了两个重要的权衡。首先，现场监测提供了关于任意湿地子集的准确水域范围信息，而卫星图像捕捉到了景观尺度的水文动态，但在水探测方面遇到了持续的挑战。卫星图像是在监测稀少和空间不均匀的地貌(如PPR)中进行模型校准的优越数据来源，在这些地貌中，监测湿地的采样不确定性超过了遥感的水探测不确定性。这两个数据源对于更同质的景观(如TPL)是等效的。第二个权衡涉及卫星图像的空间分辨率和时间覆盖率。在这方面，陆地卫星7号捕获的20年双周图像提供了对湿地景观生态水文特征的动态性质的前所未有的洞察，例如其集合人口能力的季节性和年际变化。在PPR中，这些动态的幅度远远超过陆地卫星由于与较新的图像相比空间分辨率较低而无法捕捉到生态上重要的连通性细节所带来的偏差。
Wetlands are vital components of landscapes that sustain a range of important ecosystem services. Understanding how wetland‐rich landscapes—or wetlandscapes—will evolve under a changing climate and increasing anthropogenic encroachment is urgent. Wetlandscapes are highly heterogeneous, and scaling local modelling insights from individual instrumented wetlands to characterize landscape‐scale dynamics has been a pervasive challenge. We investigate the potential to use water extent information from satellite imagery to calibrate landscape‐scale process‐based hydrological models. Applications to wetlandscapes in the Prairie Pothole Region (PPR) in North Dakota and the Texas Playa Lakes (TPL) shed light on two important trade‐offs. First, in‐situ monitoring provides accurate water extent information on an arbitrary subset of wetlands, whereas satellite imagery captures landscape‐scale hydrological dynamics but suffers persistent water‐detection challenges. Satellite imagery is a superior source of data for model calibration in sparsely monitored and spatially heterogeneous landscapes like the PPR, where the sampling uncertainty of monitored wetlands exceeds the water detection uncertainty of remote sensing. The two data sources are equivalent for more homogeneous landscapes like the TPL. The second tradeoff concerns the spatial resolution and temporal coverage of satellite imagery. In that regard, the 20 years of bi‐weekly images captured by Landsat 7 provides unprecedented insights into the dynamic nature of the ecohydrological characteristics of wetlandscapes, such as seasonal and inter‐annual changes of their metapopulation capacity. In the PPR, the amplitude of these dynamics far exceeds the bias introduced by Landsat's inability to capture ecologically important connectivity details due to its coarse spatial resolution compared to more recent imagery.