摘要
森林生态系统是陆地生态系统中的重要组成部分,其中的地上生物量(AGB,Aboveground B iom ass)在全球气候变化和碳循环研究中起着重要的作用。本文利用ETM+遥感影像,首先建立了实测叶面积指数(LAI,LeafArea Index)与实测生物量数据的回归关系,基于遥感叶面积指数图像得到初步地上生物量空间分布图;同时在短波植被指数(SWVI,ShortW ave Vegetation Index)与实测树龄之间建立了回归关系,在此基础上得到了树龄空间分布图。然后通过将植被指数(VI,Vegetation Index),LAI,树龄等变量针对不同的树种类型进行逐步回归,得到了较好的回归模型,并结合土地利用/土地覆盖估算了贵州省黎平县的地上生物量,绘制了其空间分布图。统计结果显示:总体森林生态系统的AGB与LAI和RSR(Reduced S imp le Ratio)之间有一定的相关关系(R2=0.895);杉木林的AGB与LAI和归一化植被指数(NDVI,Norm alized D ifference Vegetation Index)之间有较强的相关性(R2=0.93);针叶树种的LAI与年龄是AGB较好的估算因子(R2=0.937);阔叶林的AGB与年龄有一定的相关性(R2=0.792);混交林的AGB与LAI和SR(S imp le Ratio)有较强的相关性(R2=0.931)。结果表明,将树龄和土地覆盖/土地利用类型的信息加入到地上生物量估算模型的建立中,是一种改善利用多光谱遥感估算精度的较好的方法。结合土地覆盖/土地利用类型的高分辨率的树龄空间分布图,可为森林生态系统的可持续发展和管理提供科学的论据。
The forest ecosystem is the important component in the terrestrial ecosystem and plays an important role in global change study. Aboveground biomass （AGB） of forest ecosystem is an important factor in global carbon cycle studies. This paper uses the ETM^＋ image in combination with the field measurement data to estimate the aboveground biomass. After getting the various vegetation indexes, we get the LAI （ Leaf Area Index）, and then build the correlation between the LAI and field biomass data to get the initial biomass map. In addition, a shortwave infrared based vegetation index （SWVI） was calculated to get the forest age spatial distribution map, then, by incorporating the stand age and forest category information into the new regression model to get the final biomass map. We found that the AGB estimation for overall was related to the LAI and SR （Simple Ratio） （R^2 = 0. 895） , and for Chinese fir has a good correlation with the LAI and NDVI（ R^2 = 0. 93 ）. The LAI and AGE are good predictors for the aboveground biomass of Conifer（ R^2 = 0. 937 ） ; for the Broadleaf and Masson pine mix forest, the age is correlated to the AGB（R^2 =0. 792） ; for the Broadleaf and Chinese Fir mix forest, the AGB was strongly related to the LAI and SR（R^2 = 0. 931）. The result shows that combining the stand age and forest categories information into the AGB estimation is a better way to improve the accuracy of aboveground biomass estimation with the optical remote sensing, the high-resolution forest stand age and aboveground biomass spatial distribution map can provide basic and effective information for the forest sustainable development and management.
出处
《遥感学报》
EI
CSCD
北大核心
2006年第6期932-940,共9页
NATIONAL REMOTE SENSING BULLETIN
关键词
树龄
地上生物量
遥感
植被指数
stand age
aboveground biomass
remote sensing
vegetation index
作者简介
郑光（1982-），男，硕士研究生，毕业于南京林业大学。现就读于南京大学地图学与地理信息系统专业。研究方向为植被生态遥感、全球变化及碳循环。E-mail：njuzg@yahoo．com．cn。
