Ground Cover Reference Sites Database of Queensland

The Ground Cover Reference Sites Database of nullhas been collected by nullas 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_Qld地被参考站点数据库（Ground Cover Reference Sites Database）由未知机构收集，系澳大利亚地被监测项目的组成部分。该数据集被用于校准、验证并优化由遥感手段生成的植被盖度产品，尤其是基于MODIS与Landsat卫星传感器的相关产品。 本数据集还用于优化Guerschman等人（2009年）基于中分辨率成像光谱仪（MODIS）所生成的全国植被盖度产品。该算法通过对每8天的光谱反射率进行线性解混处理，并合成16天合成数据，从而实现全国尺度下每月区分光合与非光合地被组分的地被识别。 为保障地盖度估算结果的可靠性，研究团队在澳大利亚全境选定的站点开展了野外验证工作，以对该遥感方法的精度进行更全面的校准、验证与核查。地被参考站点数据库包含了野外验证的结果：通过沿样点截线开展观测，共获取300个样点（含农作物的样点为200个）的遥感反演盖度实测数据。 该数据库还包含各类附加观测与测量数据，涵盖景观特征、火灾痕迹、侵蚀痕迹、生物干扰痕迹、生物量估算值、基径面积测量值、土壤特征、优势植被物种，以及站点实拍照片。地被参考站点数据库的采样站点主要集中于牧场的粗放放牧系统，少量分布于混合农业区或集约土地利用区域。 野外验证工作旨在实现站点的广泛空间覆盖，并通过有限的站点重访获取时间序列数据。请通过以下链接获取该数据集：http://aekos.org.au/collection/gov.au/abares/gcrs_Qld