Estimating oak forest parameters in the western mountains of Iran using satellite-based vegetation i

来源 :林业研究(英文版) | 被引量 : 0次 | 上传用户:sddxfg
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Remote sensing is an important tool for studying and modeling forest stands.Vegetation indices obtained from Landsat-8 remotely sensed data were used to estimate the forest parameters in the west mountains of Iran.Thirtyfour sample points were selected on the map of Bayangan County,Kermanshah province,Iran.At each point,a cluster of five rectangular plots of 8100 m2 and 200 m apart was established.Some clusters were primarily sampled to determine the variance of the forest parameters.The coefficient of variation was used as a criterion for sample allocation.Stand density,canopy cover and basal area per hectare were calculated for each plot.Vegetation indices were extracted from the Landsat-8 images for each plot.Simple linear and nonlinear regressions were conducted to develop the models.The models were validated using an independent data set.Stability of model parameters was statistically evaluated.The results showed that Normalized difference vegetation index (NDVI) and Transformed normalized difference vegetation index (TNDVI) followed by Simple ratio vegetation index (SRVI) were the best predictors,explaining up to 91% of the variations with high precision.For NDVI,Soil adjusted vegetation index 2 (SAVI2) and SRVI,the cubic model was more appropriate than the linear model for predicting the forest parameters.For this model,the R-square value increased while NRMSE decreased significantly.For Infrared percentage vegetation index (IPVI),the quadratic model was better,but,for other vegetation indices,nonlinear models were not superior to linear ones.Finally,it can be concluded that Landsat-8 imagery is suitable for predicting forest parameters in the oak forests of west Iran.Of course,large plots must be selected,and pre-classification is necessary to gain accurate and precise estimations.
其他文献
利用收集到的近几年位于安徽地区郯庐地震带发生地震情况的材料,对地震级数、地震频率进行了研究,结果表明了地震灾害呈现频度高、范围广等特征.虽然多数地区的地震级数不高,
利用高通量测序技术解析河南某浓香型白酒企业35年窖龄窖泥原核微生物群落多样性及其在窖壁上层、中层、下层和窖底窖泥中的分布.厚壁菌门(71.1%)和拟杆菌门(16.3%)为供试窖泥
政府采购是指各级政府及行政事业单位为了开展日常政务活动及为了公众提供公共服务的需要,在财政的监督下,利用财政资金,以法定的方式及程序购买货物、工程及服务的行为。政府采购制度包括采购的管理、过程、程序和政策等,是国家财政的重要组成部分,它对于政府日常工作的正常进行、公共服务设施的建设及特定的社会经济政策目标的实现具有重要的意义。镇一级政府采购由于起步晚,在一定程度上发展比较滞后。镇一级政府作为我国最
To characterize the effects of plantation densities on the growth characteristics (diameter at breast level,tree height and volume) and the common wood properti