Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China.In order to strengthen forest resource management,this paper an...Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China.In order to strengthen forest resource management,this paper analyzed management-induced changes in forest structure,tree species composition and forest landscape pattern from 1987 to 2000 for Baihe Forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data.The results suggested that the area of Mature,High-Stocking,and Close-Canopy Forests decreased by 31.4%,55.9%and 10.7%respectively;volume of Mixed Forest,the native forest vegetation type,decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature,High-Stocking,Close-Canopy,and Mixed Forests.All the changes in forest structure,species composition,and landscape pattern indicated severe degradations going on with the forests in Baihe Forestry Bureau.Because of the effect of degradation to forest services,restoring forest resources and protecting biodiversity has become urgently important.The strategies of sustainable forest management need to be worked out and implemented.展开更多
By integrating forest inventory data with remotely sensed data,new data layers for factors that affect forest fire potentials were generated for Baihe Forestry Bureau in Jilin Province of China.The principle component...By integrating forest inventory data with remotely sensed data,new data layers for factors that affect forest fire potentials were generated for Baihe Forestry Bureau in Jilin Province of China.The principle component analysis was used to sort out the relationships between forest fire potentials and environmental factors.The classifications of these factors were performed with GIS,generating three maps:a fuel-based fire risk map,a topography-based fire risk map,and an anthropogenic-factor fire risk map.These three maps were then synthesized to generate the final fire risk map.The linear regression method was used to analyze the relationship between an area-weighted value of forest fire risks and the frequency of historical forest fires at each forest farm.The results showed that the most important factor contributing to forest fire ignition was topography,followed by anthropogenic factors.展开更多
基金jointly supported by the Overseas Scholar Foundation of CAS(Grant No.C13HU&C13HK)the National Natural Science Foundation of China(Grant Nos.30470302 and 70373044)China's Ministry of Science and Technology(Grant No.04EFN216600328).
文摘Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China.In order to strengthen forest resource management,this paper analyzed management-induced changes in forest structure,tree species composition and forest landscape pattern from 1987 to 2000 for Baihe Forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data.The results suggested that the area of Mature,High-Stocking,and Close-Canopy Forests decreased by 31.4%,55.9%and 10.7%respectively;volume of Mixed Forest,the native forest vegetation type,decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature,High-Stocking,Close-Canopy,and Mixed Forests.All the changes in forest structure,species composition,and landscape pattern indicated severe degradations going on with the forests in Baihe Forestry Bureau.Because of the effect of degradation to forest services,restoring forest resources and protecting biodiversity has become urgently important.The strategies of sustainable forest management need to be worked out and implemented.
基金jointly supported by the National Natural Science Foundation of China(Grant Nos.70373044 and 30470302)Jilin Yanbian Forestry Group,China's Ministry of Science and Technology(Grant No.04EFN216600328)+1 种基金Liaoning Key Technologies R&D Program(Grant Nos.2004207002 and 2004201003)the Northeast Rejuvenation Program of the Chinese Academy of Sciences.
文摘By integrating forest inventory data with remotely sensed data,new data layers for factors that affect forest fire potentials were generated for Baihe Forestry Bureau in Jilin Province of China.The principle component analysis was used to sort out the relationships between forest fire potentials and environmental factors.The classifications of these factors were performed with GIS,generating three maps:a fuel-based fire risk map,a topography-based fire risk map,and an anthropogenic-factor fire risk map.These three maps were then synthesized to generate the final fire risk map.The linear regression method was used to analyze the relationship between an area-weighted value of forest fire risks and the frequency of historical forest fires at each forest farm.The results showed that the most important factor contributing to forest fire ignition was topography,followed by anthropogenic factors.
