基于Landsat 8 OLI数据的黄土高原植被含水量的估算模型研究  

Vegetation Water Content Retrieved Using Landsat 8 OLI Remote Sensing Data on Loess Plateau

作　　者：沙莎[1] 胡蝶[1] 王丽娟[1] 郭铌[1] 李巧珍 

机构地区：[1]中国气象局兰州干旱气象研究所,甘肃省干旱气候与减灾重点实验室,中国气象局干旱气候与减灾重点实验室,甘肃兰州730020 [2]定西市气象局,甘肃定西743000

出　　处：《遥感技术与应用》2016年第3期558-563,共6页Remote Sensing Technology and Application

基　　金：公益性行业(气象)科研专项项目(GYHY201006023);甘肃省气象局气象科研项目(2015-13);中国气象局兰州干旱气象研究所基本科研业务费(KYYWF201410)共同资助

摘　　要：植被含水量(VWC)能够指示植被的水分状况,对植被生长、火灾、旱灾以及生态环境安全监测等具有重要意义,也是微波遥感估算土壤水分的重要参数之一。光谱指数法是估算植被含水量最常用的方法之一。结合地面观测及Landsat 8OLI传感器遥感影像,对平凉地区的植被含水量进行了遥感估算模型研究,结果表明:(1)平凉地区叶片含水量(FMC)与植被光谱指数没有相关关系,而等效水深(EWT)则与各植被光谱指数具有显著的相关关系(均超过95%显著性水平),其中RVI2与EWT的相关关系最显著且最稳定;(2)利用RVI2对研究区EWT进行遥感估算,其均方根误差(RMSE)为0.183,平均相对误差为8.9%,平均相对误差绝对值为26.4%;(3)研究区内大部分农田的植被含水量为0.6~0.9kg/m^2,少数农田的植被含水量达到1kg/m^2以上,这与实际考查基本一致,基本能够反映研究区内农田EWT的空间变化特征。Vegetation water content（VWC）can indicate moisture condition of vegetation,so it＇s important and meaningful to vegetation growth,fire,drought and ecological safety monitoring,also it is an important parameter for estimating soil moisture by microwave remote sensing.Building a statistical model between VWC and Spectral vegetation index is one of the most common methods to estimate VWC.Fuel Moisture Content（FMC）,Relative Water Content（RWT）and Equivalent Water Thickness（EWT）were three expression for VWC.Taking Pingliang as an example,FMC and EWT were calculated basing on the ground observation,and then EWT was estimated by using Landsat8 OLI remote sensing data in this paper.Results shown that：（1） Fuel Moisture Content（FMC）is not correlated with spectral vegetation indices,while EWT is significant correlated with spectral vegetation indices with more than 95% significant level.Using cross validation concept,an experiment is executed,which shows the relations between RVI2 and EWT is most significant and most stable.（2） EWT was estimated by RVI2,its Root Mean Square Error（RMSE）is 0.183,the average relative error is 8.9%,and the average absolute value of relative error is 26.4%.（3） Most of EWT was 0.6~0.9kg/m^2 on farmland in study area,and a small of it was reaches 1kg/m^2 or more,consistent with the field situation,and can reflect the spatial distribution of EWT.

关 键 词：EWT 比值植被指数 平凉 植被含水量 

分 类 号：TP79[自动化与计算机技术—检测技术与自动化装置]