搜索结果: 1-15 共查到“知识库 森林统计学”相关记录32条 . 查询时间(0.558 秒)
成都市森林植被碳储量及空间分布格局
成都市 碳储量 碳密度 空间分布
2021/7/7
为了探明成都市森林植被碳储量和碳密度的数量特征及空间分布规律,以成都市2017年森林资源规划设计调查成果为数据源,运用生物量转换因子法估算生物量,实测和选取植被含碳率,基于小班尺度估算成都市的森林植被碳储量和碳密度,并运用ARCGIS10.5软件进行空间分布格局分析。结果显示:(1)全市森林植被总碳储量为1.3369×107t,平均碳密度为11.71t/hm2,其中林分碳储量占78.50%,是全市...
基于Sentinel-1A微波遥感数据的森林蓄积量估测
Sentinel-1A 森林蓄积量 微波遥感数据 纹理特征 随机森林法 偏最小二乘法 估测
2021/7/13
Sentinel-1A作为开源的集微波和光学数据一体的卫星数据源,给森林资源调查和监测提供了重要的数据源。为了探索Sentinel-1A数据在森林资源调查中的可用性,以Sentinel-1A为遥感数据源,结合地面样地森林蓄积量调查数据,采用随机森林法和偏最小二乘法两种模型对云南省普洱市思茅区的森林蓄积量进行预测以及遥感反演。通过对遥感影像进行一系列预处理,提取微波遥感数据VV和VH极化下的后向散射...
以贵州赤水竹浆原料林为例,采用正态分布、威布尔分布和柯西分布3种分布模型对撑绿竹、慈竹、黄竹和绵竹的直径分布进行模拟;采用幂函数模型对4个竹种其径阶与平均质量的关系进行拟合。结果表明,对于直径分布的平均模拟精度,正态分布模型为78.88%~91.61%、威布尔分布模型为82.07%~92.92%、柯西分布模型为66.60%~75.47%,其中,威布尔分布模型的模拟效果最好;对于径阶与质量的关系,幂...
我国第九次森林资源清查中的资源动态研究
全国森林资源清查 森林总量 森林结构 增长潜力
2021/7/12
为了总结第九次全国森林资源清查(2014—2018年)的主要结果,并将其运用于我国林业发展的相关分析和政策的制定,本研究结合第八次全国森林资源清查(2009—2013年)结果,分别从森林总量和森林结构两类指标进行对比分析研究。结果表明:较上一次清查,本调查期,全国森林总量呈增长趋势。森林面积增加了6%,森林覆盖率增加了1.33%,森林蓄积增加了16%,全国森林结构进一步优化。森林面积中,国有林和集...
国家储备林研究进展及其林分质量精准评价研究
森林质量精准提升 国家储备林制度 评价指标体系 多功能森林
2021/7/12
本文通过文献分析的方法,回顾了我国国家储备林制度确立的进程,综述了国家储备林相关研究进展,围绕国家储备林大径材培育和珍贵用材储备的建设生产目标,提出了国家储备林森林质量精准评价方法体系的初步思路,以期提高国家储备林现有林改培及长期可持续经营的精准度和科学性。
森林植被和降水量是区域生态环境中的两个重要地理要素,森林植被覆盖率变化在一定程度上影响区域降水量。以广西金城江区、贵州七星关区、湖南零陵区3个区域为研究对象,采用遥感技术基于地理空间数据云Landsat4-5TM、Landsat8OLI_TIRS卫星数字资料,提取3区1988-2017年的森林覆盖率,并从中国气象数据网获取相应年份的年降水量、雨季降水量等数据,使用SPSS17.0进行了森林植被覆盖...
DETECTION OF LANDSLIDES WITH SAR POLARYMETRY: CASE STUDY OF SOUTH-EASTERN COLOMBIA
Backscattering Coefficient Dispersion Mechanism Landslides Polarimetry SAR (PolSAR) Entropy – Alpha Parameter Classification Principal Component Analysis
2018/4/18
SAR polarimetry (PolSAR) is a method that can be used to investigate landslides. Polarimetric scattering power decomposition allows to separate the total power received by the SAR antenna, which is di...
RAPID MAPPING OF FORESTED LANDSLIDE FROM ULTRA-HIGH RESOLUTION UNMANNED AERIAL VEHICLE DATA
UAV landslide object-based image analysis Bartı n Black Sea Region rapid mapping
2018/4/18
The Black Sea Region is one of the most landslide prone area due to the high slope gradients, heavy rainfall and highly weathered hillslope material conditions in Turkey. The landslide occurrences in ...
在杉木、松树、桉树、一般阔叶树人工林中分别设置25-31块共110块30m伊30m样地(分为9个10m伊10m样方)进行每木调查,每块样地分别组合为100m2、200m2、300m2、400m2、600m2和900m26个不同面积的样地,分析了不同样地面积的林分平均直径、平均高、优势高、每公顷断面积、每公顷株数(N)、每公顷蓄积量(M)的变化情况。结果表明,各个优势树种中,不同面积大小样地的軍D、...
Development of models for forest variable estimation from airborne laser scanning data using an area-based approach at a plot level
Python Fusion forest inventory linear regression Norway spruce
2016/4/6
Airborne laser scanning (ALS) is increasingly used in the forestry over time, especially in a forest inventory process. A great potential of ALS lies in providing quick high precision data acquisition...
Evaluation of three methods for estimating the Weibull distribution parameters of Chinese pine (Pinus tabulaeformis )
Weibull distribution diameter distribution parameter estimation
2015/3/12
Weibull distribution was used to fit tree diameter data collected from 86 sample plots located in Chinese pine stand in Beijing. To estimate the Weibull distribution parameters, three methods [namely ...
The applicability of the Pipe Model Theory in trees of Scots pine of Poland
Scots pine Pipe Model Theory sapwood tree crowns profile theory biometric traits
2015/3/12
In order to test the application importance of the Pipe Model Theory and to develop models for the share of sapwood in tree stems, a total of 114 Scots pines (Pinus sylvestris L.) were felled within t...
Some methodological aspects of the National Forest Inventory and Monitoring in Slovakia
tree heights tree volume deadwood volume biometrical models Slovak forestry
2015/3/12
The work presents the conceptual information about the National Forest Inventory and Monitoring in Slovakia. It introduces some methodological approaches to the field data collection (determination of...
Selected properties of European beech (Fagus sylvatica L.)
beech wood ring width density swelling
2015/3/12
The paper deals with the variability of tree-ring width, with the density and swelling (volumetric swelling and swelling in individual anatomical directions) of wood from two different locations. Furt...
Effect of negative factors on the use of oak and beech for decorative veneers
veneer qualitative yield cutting
2015/1/29
The paper summarizes results of an institutional research aimed at the analysis of relationships between the quality of decorative veneers of oak and beech and negative factors decreasing the use of v...