Research Of Measuring Trees Factor Method By Remote Sensing

Forest resources survey and monitoring is the foundation of forest management and operation, which can provide a strong basis for forest resources sustainable development depends on identify and implement good quality of forest resources. After half a century development, China’s forest resources survey and monitoring has formed a more comprehensive forest inventory system, according with China’s national conditions and forestry developments. At present, directions of the forestry workers is to obtain the forest resources using the advanced scientific, besides, to monitor forest variation situation changes more comprehensive, objective information for forest management.This study attempts to change the traditional methods of forest resources survey, respectively using close-range photogrammetry, aerial photography and remote sensing measurement techniques to obtain forest management information, which based on reducing labor intensity and improving forest information achieve efficiency, made the forest resources survey automatic, intelligent, modern and scientific Provide the best basis for the realization of a "digital forest" and lay the cornerstone for the digital healthy forest system.1. This study is based on the close-range photogrammetry theory and technology, respectively using an ordinary digital camera and a3D digital camera to take pictures for the plant, combined with terrestrial photogrammetry theory and methods for solving its DBH plant stumpage value:Using digital images measurements and proportional to DBH solver, estimation accuracy achieved87.65%.Establishing the relationship between the image of coordinates and the type of the object in three-dimensional space coordinates of the single tree to calculate the value of the picture through diameter at breast height by classical collinearity equation, estimation accuracy was88.87%. Using the function of the3D digital camera to get a group image pair at the same time, as to adopt the way of horizontal straight photography, the photos taken at the same time as the calculating DBH was ineffective, but for the use of3d camera will provide an idea to solve the parameters of trees.2.Collected various measurement factors of the tree at first and estimated the plant scale of tree height, crown width and the stand scale average height, average Stand Crown, crown density, which is based on the methodology theory and aerial photogrammetry of forest resource survey. Establishment the air volume model used the stand factors. Then the method of the aerial photography acquired factor of tree measuring model, to estimate individual tree diameter at breast height, finally, to verify the accuracy of each model, comparison of progress, the tree height, diameter at breast height estimation model to calculate the optimal precision.3. Biomass estimated through satellite remote sensing technique using resources three satellite images and Landsat TM images. Not only the spectroscopic, vegetation and terrain factor as inversion biomass factor, but also added texture factor involved in inversion, at the same time, each pixel value used the average center pixel (3×3scale), as the center pixel value. Finally, through multiple linear regression, achieved the biological optimal forest model, and estimated the forest biomass and biomass distribution map of Beijing city.Research and measurement of three different scale factor of tree, from local to overall, to research the forest investigation factor of forest in different space within the scope of the collection has important practical significance to the management of forest resource. The main technology that proposed in this paper is to change the traditional forest resource survey time-consuming, laborious, improve the level of survey data, reduce the important field survey labor intensity and production cost of forest resources.