1990-2021年环塔里木盆地植被覆盖度(FVC)时空数据集

A dataset of temporal-spatial FVC in the Ring Tarim Basin from 1990 to 2021

塔里木盆地是生态极端脆弱区,更是人为扰动剧烈区,荒漠化问题尤为突出。植被覆盖度能够很好地反映地表植被的繁茂程度,是荒漠化监测的一个重要指标。开展区域植被覆盖度监测是掌握荒漠化动态变化,全面分析荒漠化成因等方面研究的基础。研究基于GEE遥感云平台,以1990–2021年LANDSAT卫星植被生长季(4–10月)影像为数据源,获取了环塔里木盆地1990–2021年间7期植被覆盖度数据集。研究通过采用0.5%置信度截取NDVI的上下阈值,获得纯植被覆盖像元和纯土壤覆盖像元的NDVI值,来消除年际间气候差异对植被覆盖度计算的影响,保证各年度植被覆盖度计算的一致性。数据集使用109块无人机正射样地,经过预处理及植被指数法加大津算法得到的FVC值作为验证样本。数据集精度为R^(2)=0.79、线性表达式为y=0.8126x-0.0267。本数据集可为荒漠化变化、驱动机制等方面的研究提供数据支撑。

The Tarim Basin is an area with extremely fragile ecology and severe desertification subject to the ravages of human activities.As an important index of desertification monitoring,vegetation coverage can well reflect the luxuriant degree of surface vegetation.The monitoring of regional vegetation coverage is the basis of mastering the dynamic change of desertification and analyzing the causes of desertification.Using LANDSAT vegetation growth season(April-October)images from 1990 to 2021 as data sources,we obtained seven vegetation coverage data sets from 1990 to 2021 in the Ring Tarim Basin based on GEE remote sensing cloud platform.We intercepted the upper and lower thresholds of NDVI by adopting 0.5%confidence level to get the NDVI values of pure vegetation cover pixels and pure soil cover pixels,so as to remove the effect of the interannual climate differences on vegetation coverage calculation,and ensure the consistency in the calculation of vegetation coverage for each year.The observation work was carried out in 109 UAV orthorectified sample plots.In the following of data pre-processing,we obtained FVC values as validation samples by using a combined algorithm(vegetation index method and Otsu algorithm).The precision of the dataset is R^(2)=0.79 and the linear expression is y=0.8126x-0.0267.This dataset can provide data support for the research of desertification change and driving mechanism.