Abstract
To reach 21th century, the protection of ecological environments and conservation of natural forests are the current trend on the earth. Therefore, the ban of natural forest cut is still a continuing tendency. Under the circumstance, it is role important that sustainable and intensive management of man-made forests through a breeding desired trees and a series of alternative silvicultural tending strategies and accommodating forest certification principles. Forests have the characteristics of renewable resources. Through appropriate management and tending practices, high productivity and carbon sequestration in forests can be achieved. However, afforestation was largely focused on establishment of monoculture plantation in the past. And for lack of thinning practices and stand density management, these plantations were faced with deterioration and soil erosion problems. Thinning operations can effectively control stand density and promote the volume growth and quality of timber. In addition, they will also impact forest biodiversity, ecosystem function and structure, soil and water conservation, landscape, and even social economy of local communities, etc. While the forest certification system is currently being actively developed in Taiwan, forest operations should take into account the benefits and soundness of various aspects rather than simply consider the cost and efficiency. Therefore, this project aims to explore the impacts of different thinning strategies on the sustainable management of plantations and to accommodate operating techniques to forest certification principles. This project aims to study the above important practical issues to provide scientific bases for the forest management sectors. On the other hand, unmanned aerial system(UAS) has the merits of easy-operating, high mobility, economics and safety . The technology of aerial photo can provide instant high image resolution photo data of forest stand, and the distribution of forest resource. On the aspect of terrain change, the UAS can also provide sub-meter level digital surface model(DSM). This study try to apply above technique to collect instant data of forest land and stand. The mathematical model will be established by considering the costs of forest road construction and maintenance, logging and transportation. The optimizing forest road density will to calculated for bamboo tree and plain area. The results can be reference for machinery application and forest management.