TM卫星影像图在新林林业局森林资源二类复查中的应用

对ＴＭ卫星影像图在新林林业局森林资源二类复查中的使用效果进行了分析。表明应用ＴＭ卫星影像图进行目视判读森林土地类型具有较高的准确率，在与旧航片结合使用时可提高小班区划质量。     

TM影像图在森林资源二类调查中的应用

ＴＭ影像图应用于森林资源二类调查，是林业勘察技术的一项新的内容。我院在１９９４年对巴林、南木林业局进行二类调查时，在调查地区试用了陆地卫星ＴＭ图像，采取全面试验重点研究的方法，全面采用旧航片与ＴＭ影像图相结合的调绘方法，并根据调查地区的林分特点，分别选取了６个小流域进行ＴＭ影像图在二类调查中应用的重点研究，取得了一定的经验。１９９５年在进行五岔沟林业局森林资源二类调查中，也采用了类似上述的调绘方法。通过实践证明，此种调查方法应用效果较好。     

用航片和样地双重抽样法提高森林蓄积量估测精度

本文就充分利用航空影像来提高蓄积量估测精度问题进行了研究,并采用双重分层抽样方法对航片样地的效率、样地布设形式及大小给予了评价,特别是引入了非成图抽样方法,使双重抽样更显得方便和高效。     

航片在森林经理调查中的运用

该文介绍了航片的产生、特点及应用范围,以及如何利用航片的高分辨率、影像清晰细致等特点辅助进行森林经理调查,对提高森林经理调查的调查精度和调查效率进行了详细的介绍。     

基于大比例尺航片的针叶树种冠幅的提取

基于凉水国家级自然保护区2009年拍摄的1：2000航空像片和同期森林资源二类调查的固定样地数据,采用子像元分类方法分别提取出红松、落叶松和云冷杉的专题影像图。在此基础上,将栅格专题影像图转换为矢量图形,采用目视解译的方法提取上层针叶林的树冠信息。通过将针叶树冠形似为圆形提取出各树种的冠幅,用固定样地实测数据进行对比分析和精度评价,并建立航片上提取冠幅与实测冠幅之间的一元线性回归模型。结果表明：红松、落叶松和云冷杉冠幅的提取精度分别达到83．50％、84．35％和82．26％,其预测精度分别达到83．60％、81．46％和83．57％。     

基于RS和GIS的森林资源类型三维地形显示与分析

本文以安徽省东至县梅城林场为研究对象,在遥感(RS)与地理信息系统(GIS)的支持下,运用遥感软件Erdas9.0对2011年同期的LandsatETM+遥感影像进行分类,形成森林资源类型影像分类图;以ArcGIS9.3为数据加工平台,对林场1∶10000地形图等高线进行矢量化,生成数字高程模型(DEM)。在ArcGIS软件环境下,将森林资源类型影像分类图和DEM融合,实现森林资源类型三维地形显示,在此基础上,进一步对森林资源的分布和海拔因子关联性进行了分析。     

SPOT5遥感影像在林业二类调查中的应用

采用ERDAS IMAGINE图像处理软件,对青海省互助县境内的北山林场的SPOT5遥感影像进行处理,包括原始数据导入、正射纠正、影像融合、波段组合、影像增强等处理过程以及数字正射影像图(DOM)的制作。探讨SPOT5遥感影像在林业二类调查中的应用处理方法及SPOT5影像的应用前景。经现地验证,以SPOT5遥感卫星影像为底图,通过人机交互目视解译方法区划判读小班能满足林业二类调查的需要,该影像数据能作为1∶10000专题图制作的基础数据。     

卫片与航片联合判读的森林调查方法

<正> 卫片与航片联合判读的森林调查方法,集中了卫星像片与航空像片以及地形图三方面的优点,为森林调查闯出了一条新路。该方法首先利用卫片所显示的各种地类的影像,配合航空像片或过去的调查图,在卫星像片上区划出各种地类界线,作为我们要调查地区的基本图。这样节省了大量的外业调绘工作。其次,     

利用1:14000航摄象片测制1:2000象片平面图的技术

随着我国林业建设的发展,航测成图的任务越来越重,尤其近几年来随着林业调查规划工作的发展,林业规划所需要的大比例尺地形图和象片图日益增多,采用大平板仪和其他仪器的作业,已难以满足要求。如何利用已有1:14000比例尺航摄资料测制大比例尺地形图和象片图就成为急待解决的课题。我队于1979年4月在汪清局和有关林场进行了利用1:14000航摄象片测制1:2000比例尺象片平面图的试验工作,取得了予期的效果现将试验情况总结如下:     

1∶1万地形图分幅及新旧图幅号转换方法

该文介绍了1∶1万比例尺地形图的新旧分幅标准,新旧图幅号的转换方法以及新旧图幅号与经纬度之间的转换公式,有利于采用新分幅标准数据的推广,为辽宁省林业生产中地形图、航片的综合利用带来方便.     

基于数字图像处理的桉树叶面积分析

本文以桉树叶为材料,以Sigmascan和Photoshop软件为例,详细介绍了基于数字图像处理法分析叶面积过程,与现行的常规方法测量结果进行了比较,结果表明数字图像处理法操作简捷、测定结果精确、且省时省力;进一步对不同影响因子(像素、图像处理和选择阈值)对数字图像法测定值影响进行了分析讨论,为树木叶面积测量以及叶片图像处理集成软件的开发提供参考。     

基于遥感技术的退耕还林监测研究——以甘肃省清水县为例

利用1∶5万地形图的DRG(数字栅格图),采用二次多项式法和双线性内插法;对TM图像进行几何校正处理。以TM432为最佳波段组合。在ERDAS遥感数字图像处理系统支持下,对清水县1997年和2008年两期的归一化差异植被指数(NDVI)进行了统计计算,并获得了其植被指数分布图、植被指数差值图及统计表。结果表明:2008年的植被指数相对1979年有了很大程度的提高,植被指数大于0以上的面积增加了13.4%。全县60%土地的NDVI值都有不同程度的增加。     

伞滑刃线虫交合刺形态图像的规范化和定位算法

应用数字图像处理与分析技术中的最小外接矩形算法和镜像变换算法,用Visual c 作为开发工具,通过编程实现计算机对伞滑刃属线虫交合刺形态图像鉴定规范化和定位的智能化。输入伞滑刃属66个有效种的交合刺形态图像运行程序,均获得正确的定位结果。     

Clear-cut Detection in Boreal Forest Aided by Remote Sensing

The study compares the applicability of different remote sensing data and digital change detection methods in detecting clear-cut areas in boreal forest. The methods selected for comparisons are simple and straightforward and thus applicable in practical forestry. The data tested were from Landsat satellite imagery and high-altitude panchromatic aerial orthophotographs. The change detection was based on image differencing. Three different approaches were tested: (1) pixel-by-pixel differencing and segmentation; (2) pixel block-level differencing and thresholding; and (3) presegmentation and unsupervised classification. The study shows that the methods and data sources used are accurate enough for operational detection of clear-cut areas. The study suggests that predelineated segments or pixel blocks should be used for image differencing to decrease the number of misinterpreted small areas. For the same reason the use of a digital forest mask is crucial in operational applications.     

原木端面图像检尺直径识别的一种算法

论述了应用计算机图像处理和识别技术来识别不规则圆形类目标的问题,以成捆原木端面图像为实例,提出一种原木端面检尺直径识别的算法。     

Effect of settings of digital fisheye photography to estimate relative illuminance within forest under low light conditions

In order to evaluate the effects of settings of digital fisheye photography on estimates of relative illuminance (RI) within a forest under low light conditions, we assessed the effectiveness of some estimators, i.e., canopy openness (CO), sky factor (SF), and diffuse transmittance (DIF). The estimates were calculated from digital hemispherical photographs taken with two different exposure settings, i.e., the reference exposure setting and the auto-exposure setting. We also presented a new estimator (%Exposure), which does not require image analysis, and compared it with other estimators calculated from a digital hemispherical photograph using image analysis. The CO, SF, and DIF calculated from digital hemispherical photographs taken with auto-exposure setting were not significantly correlated with RI. However, those calculated from digital hemispherical photographs taken with reference exposure settings were significantly correlated with RI. On the other hand, %Exposure showed a slightly higher correlation with RI compared with the other estimators.     

Determination of the spatial distribution of trees from digital aerial photographs

This study examined the possibilities of using computerized digital aerial photograph interpretation in determining the spatial distribution of trees. The material of the study included eight mapped stands in the municipality of Hyytiälä (61°50′N and 24°18′E), in southern Finland. The aerial photographs used were taken in June 1995 at a scale of 1:5000. Two approaches for determining the spatial pattern of trees were used. Firstly, in the point-process based approach used in this study, the individual trees in the digital aerial photograph were segmented by a robust segmentation method, based on recognition of the pattern of tree crowns with sub-pixel accuracy. Secondly, the crown coverage was determined by region growing segmentation combined with active surface representation. The significance of the differences in the means of image coverage pattern indices between the various spatial distribution categories was tested with one-way variance analysis. Because the process misclassified clustered spatial patterns as regular patterns, and regular patterns as random patterns, the usability of digital aerial photographs seems to be limited for the point-process based determination of the spatial pattern of trees if the scale is 1:5000 or less. When image coverage pattern indices were applied, the differences in the means of the spatial distribution categories proved not to be clearly statistically significant due to the great variation within classes. However, interpretation of crown coverage could have applications in practical forestry due to the low resolution requirements for the images used.     

Measurement and Calculation Methods of a Stem Image Information

The paper shows a study on 2-D stem image information collected by a digital camera. Information on a single stem is obtained through calculations after the application of the direct linear transformation model of close-range photogrammetry and binocular stereo vision technology, so that the calculating problem between stem image information and its 2-D coordinate can be solved. Furthermore, the 2-D processing methodology for measuring tree image information simplifies calculating equations and increases calculating speed. Although computer stereo vision techniques for collecting parameters of a single stem shape are comparative, complicated, and expensive, research indicates the efficiently and feasibility of close-range photogrammetry for stem image information. Translated from the Journal of Beijing Forestry University, 2005, 27(1) (in Chinese)     

0.5M分辨率航摄数字影像数据在森林资源规划设计调查中的应用

以0.5 M分辨率航摄数字影像数据为基础,结合以往调查设计及经营资料,对森林资源规划设计调查小班的部分因子进行判读,探讨高分辨率航摄数字影像数据在森林资源规划设计调查中的应用,结果表明:利用0.5M分辨率航摄数字影像数据进行小班因子判读,可以作为小班因子调查的辅助手段,并可显著提高小班调查质量及效率。     

森林面积方法研究

本文通过对遥感图像的处理和光谱特征信息的分析,应用ETM 影像数据和地面调查数据,研究了遥感数据处理技术在植被信息提取中的应用,尝试对高山峡谷区的森林资源调查提出较为完善的计算机图像处理技术和自动分类方法。对道孚县台站林场和麻孜林场地类的分类结果表明:运用TM453波段融合能够达到较好的图像增强效果;运用无监督分类方法提取森林面积能达到较高的分类精度;NDVI比RVI更能突出植被信息和消除山体阴影的影响。