Ground Cover Reference Sites Database of South Australia

The Ground Cover Reference Sites Database of South Australiahas been collected by Department of Environment, Water and Natural Resources, South Australiaas part of the Ground Cover Monitoring for Australia project. The data is being used to calibrate, validate and improve vegetation fractional cover products derived from remote sensing, in particular the satellite sensors MODIS and Landsat. The data is being used to improve the national fractional vegetation cover product of Guerschman et al. (2009) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS). This algorithm enables national, monthly identification of ground cover separating the photosynthetic and non-photosynthetic components by applying a linear unmixing methodology for spectral reflectance evey 8 days as 16-day composites. For confidence in its ground cover estimates, the results were verified in the field at selected sites across Australia to allow more extensive calibration, validation and verification of accuracy of the remote sensing method. The Ground Cover Reference Sites Database represents the results of the field validation of remotely determined cover measurements by observing cover along point intersects with a total of 300 points (or 200 points with crops). It also has additional observations and measures such as landscape features, fire evidence, erosion evidence, biotic disturbance evidence, biomass estimates, basal area measurements, soil features and dominant vegetation species, as well as site photographs. The Ground Cover Reference Sites Database focuses on sites in extensive grazing systems of the rangelands and, to a lesser extent, in the mixed farming or intensive land use zone. Field validation aims at obtaining a wide spatial coverage of sites, with limited site revisits for temporal coverage. Please use the following URL to access the dataset: http://aekos.org.au/collection/gov.au/abares/gcrs_SA南澳大利亚州地表覆盖参考站点数据库（Ground Cover Reference Sites Database）由南澳大利亚州环境、水与自然资源部（Department of Environment, Water and Natural Resources, South Australia）依托“澳大利亚地表覆盖监测”项目采集构建。本数据集用于校正、验证并优化遥感反演得到的植被分盖度产品，特别是基于中分辨率成像光谱仪（Moderate Resolution Imaging Spectroradiometer，简称MODIS）与Landsat卫星传感器的反演产品。同时，该数据集还用于优化Guerschman等人2009年基于MODIS开发的国家级植被分盖度产品。该算法通过对光谱反射率开展线性光谱分解，以16天合成产品的形式每8天完成一次识别，可在全国尺度上区分地表覆盖的光合与非光合组分，实现月度地表覆盖监测。为保障地表覆盖反演结果的可靠性，研究团队在澳大利亚全境选取典型站点开展野外实地验证，以进一步完善遥感反演方法的精度校准、验证与准确性确认流程。南澳大利亚州地表覆盖参考站点数据库收录了野外实地验证的成果：通过沿样点截线开展覆盖度观测，共设置300个样点（农田区域设置200个样点），获取遥感反演覆盖度的实地验证数据。该数据集还包含额外的观测与测量项，涵盖景观特征、火灾痕迹、侵蚀迹象、生物干扰证据、生物量估算、基断面积测量、土壤特征、优势植被物种，以及站点实拍照片。本数据集的研究站点主要集中在牧场的大规模放牧系统中，少量分布于混合农业区或集约土地利用区域。野外验证的目标是实现站点的广泛空间覆盖，并通过有限的重访次数获取时间序列覆盖数据。请通过以下链接获取该数据集：http://aekos.org.au/collection/gov.au/abares/gcrs_SA