Cross-Site: Spatio-temporal Dynamics of Canopy and Soil Moisture: Linking Synthetic Aperture Radar Image Phenomenology with Ecosystem Processes

土壤水分是许多生态和生物物理过程的关键控制因子。虽然有多种技术可用于对土壤湿度进行点估计，但空间广泛的调查在后勤上可能很困难，并且充满了插值问题。土壤湿度遥感提供了详尽的空间采样的可能性。微波传感器（主动式和被动式）在土壤湿度测量中的有效性已经得到了很好的研究。然而，很少有研究集中在自然景观的雷达图像模式。然而，显然需要评估合成孔径雷达（SAR）在陆地表面过程的常规环境监测方面的潜力。随着星载SAR平台的数据越来越容易获得，对植被景观的环境监测将在今后十年中增加。该项目涉及使用来自欧洲、加拿大和日本轨道平台的SAR数据，以解决冠层和土壤湿度的变化及其生态后果。这些数据增强了目前在两个美国国家科学基金会长期生态研究（LTER）地点的调查，一个是堪萨斯州东北部的康扎草原研究自然区，另一个是新墨西哥州中部的塞维利亚国家野生动物保护区。两个LTER站点都位于生态过渡带（过渡带）内，土壤湿度是植物生产力和物种组成的主要决定因素。主要产品是特定地点的土壤湿度和冠层变化时序图。然后，这些数据将用于将遥感和地面实况数据与生态过程联系起来。

Soil moisture is a key controlling factor for numerous ecological and biophysical processes. While diverse techniques are available to make point estimates of soil moisture, spatially extensive surveys can be logistically difficult and fraught with problems of interpolation. Remote sensing of soil moisture offers the possibility of exhaustive spatial sampling. The efficacy of microwave sensors (both active and passive) in measuring soil moisture is well-studied. However, little research has focused on patterns of radar imagery of natural landscapes. Yet, there is a distinct need to assess the potential of Synthetic Aperture Radar (SAR) for routine environmental monitoring of land surface processes. Environmental monitoring of vegetated landscapes will increase during the next decade as data from spaceborne SAR platforms become more readily available. The project involves the use of SAR data from the European, Canadian, and Japanese orbital platforms to address the variation in canopy and soil moisture and its ecological consequences. These data augment current investigatio ns at two NSF Long Term Ecological Research (LTER) sites, Konza prairie Research Natural Area in the northeast Kansas and Sevilleta National Wildlife Refuge in central New Mexico. Both LTER sites are located within ecological transitional zones (ecotones) in which soil moisture is a major determinant of plant productivity and species composition. The primary products are site-specific time series of soil moisture and canopy change maps. These data will then be used to link remote sensing and groundtruth data with ecological processes.