A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings...A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings and the allelopathy between the two tree species. Four concentrations (100 g. kg i, 50 g. kg^-1, 25 g. kg^-1 and 12.5 g. kg^-1) were prepared for each kind of extracts. Result showed that the water extracts with low and moderate concentrations accelerated the growth of collar diameter and increased biomass and root/shoot ratio of walnut seedlings. The water extracts from branches and barks with low and moderate concentrations accelerated the height growth of the seedlings, while those from leaves and roots slightly decreased the height growth of seedlings. The fact that application of water extracts of larch improved the growth of Manchurian walnut attributes possibly to the allelopathy between the two tree species.展开更多
In a tropical wet montane evergreen forest in the southern peninsular India, the estimated stocking of dead wood is 90 ± 3 stems·ha-1 and the total dead wood volume is 70.7 m3·ha-1. When the logs (downe...In a tropical wet montane evergreen forest in the southern peninsular India, the estimated stocking of dead wood is 90 ± 3 stems·ha-1 and the total dead wood volume is 70.7 m3·ha-1. When the logs (downed dead trees more than 10.1 cm in diameter) constitute about 80% of the total deadwood stocking and volume, the rest is by snags (sound and rotting standing dead trees). Since the shola forest trees are characterized by their short stature with low to medium girth, about 89% of the total number of deadwood is of the size ranging from 10.1 cm to 40.0 cm in diameter. The estimated standing dead wood/standing live tree ratio is 0.16 indicating that the forest represents an old stand. Variations observed between logs and snags to change from a given decay class to the higher decay classes in two year period could be attributed to the facts that the logs would be in contact with soil for a relatively longer time and in turn would be in more contact with microorganisms and other decomposing agents.展开更多
Rupa Lake is small advancing eutrophic lake covering about 115 ha of the Lekhnath Municipality in Kaski district of western Nepal. The environment around the lake has been improved over a period of 10 years. Conservat...Rupa Lake is small advancing eutrophic lake covering about 115 ha of the Lekhnath Municipality in Kaski district of western Nepal. The environment around the lake has been improved over a period of 10 years. Conservation practices were initiated by communities including the Rupa Lake Restoration and Fishery Cooperative (RLRFC). As a result, an abundance of non-timber Forest Products (NTFP) has increased considerably. At present, 49 NTFP are available in the lake basin. Some households (HH) i.e 10% has additional income from NTFP. It is an indirect source of food security for local people. They sell NTFP products to generate income. A few households have already started farming of NTFPs. Availability of fodder and fuel wood from community forest has significantly contributed to the livelihoods of people where as wild edible fruits and vegetables have become supplementary for food security. There is yearly food security for 57% of HH with 22% having surplus food. 5% of HH has food security for less than three months where as 19% HHs have food security for more than six months. However, livelihood and nutritional security have improved by fish farming in lake. This lake is most important for the local environment and also helps eco-tourism. The study found that 92% observed the climate change in the form of a rise in temperature (〉 70% HHs); unpredictable rainfall (〉 75% HHs); shifting rainfall (〉 60% HHs); phonological changes (〉 50%). It showed that the lake supports the restoration of natural water capacity, maintain local climate and sound environment by better natural resource management for an environment friendly ecosystem.展开更多
Based on forest inventory data (FID) at sublot level,we estimated the carbon sequestration in forest vegetation of Beijing,China in 2009.In this study,the carbon sequestration in forest vegetation at sublot level was ...Based on forest inventory data (FID) at sublot level,we estimated the carbon sequestration in forest vegetation of Beijing,China in 2009.In this study,the carbon sequestration in forest vegetation at sublot level was calculated based on net biomass production (ΔB) which was estimated with biomass of each sublot and function relationships between ΔB and biomass.The biomass of forested land was calculated with biomass expansion factors (BEFs) method,while those of shrub land and other forest land types were estimated with biomass,coverage and height of referred shrubs and shrub coverage and height of each sublot.As one of special forested land types,the biomass of economic tree land was calculated with biomass per tree and tree number.The variation of carbon sequestration in forest vegetation with altitude,species and stand age was also investigated in this study.The results indicate that the carbon sequestration in forest vegetation in Beijing is 4.12 × 106 tC/yr,with the average rate of 3.94 tC/(ha·yr).About 56.91% of the total carbon sequestration in forest vegetation is supported by the forest in the plain with an altitude of < 60 m and the low mountainous areas with an altitude from 400 m to 800 m.The carbon sequestration rate in forest vegetation is the highest in the plain area with an altitude of < 60 m and decreased significantly in the transitional area from the low plain to the low mountainous area with an altitude ranging from 200 m to 400 m due to intensive human disturbance.The carbon sequestration of Populus spp.forest and Quercus spp.forest are relatively higher than those of other plant species,accounting for 25.33% of the total.The carbon sequestration in vegetation by the forest of < 40 years amounts to 45.38% of the total.The carbon sequestration rate in forest vegetation peaks at the stand age of 30–40 years.Therefore,it would be crucial for enhancing the capability of carbon sequestration in forest vegetation to protect the forest in Beijing,to limit human disturbance in the transitional area from the plain to the low mountain area,and to foster the newly established open forest.展开更多
The phytogeographical system for vegetation classification splits the vegetation in first level types: forest and grasslands. The forest type can be recognized in tropical rain forest and seasonal depending on the en...The phytogeographical system for vegetation classification splits the vegetation in first level types: forest and grasslands. The forest type can be recognized in tropical rain forest and seasonal depending on the environmental conditions. This determines the occurrence of deciduous species in big or small quantity. And the grasslands are Savannah in majority. This work proposed probabilistic methods to classify these vegetation types based on priori occurrence of species. The test was carded out with forest inventory data using ten vegetation fragments in farm of Embrapa and Cascata's park in Sete Lagoas city, Minas Gerais, Brazil. The distribution of species with occurrence in different types was adapted to set theory and Bayes theorem. In this way, it is possible to calculate belonging of species on vegetation types. The results were compared with usual classification. The main contribution of probabilistic methods was to increase the information to classify tree and shrub vegetation inventoried. It is especially recommended for transition regions between vegetation types.展开更多
This paper examines human impact on stands and individual trees of Pinus yunnanensis growing near the small mountain villages of Pianshui and Yangjuan in southwestern Sichuan Province,China.In an effort to assess whet...This paper examines human impact on stands and individual trees of Pinus yunnanensis growing near the small mountain villages of Pianshui and Yangjuan in southwestern Sichuan Province,China.In an effort to assess whether use of these forests was sustainable,we examined the effects of human use in two ways.First,we directly measured the effect of cutting branches,for fuel and fodder,on tree growth.We hypothesized that branch cutting would negatively impact tree growth.We established 12 plots on four hills and compared 14 pairs of trees,one tree in each pair with an apparently full crown and the other with a considerable portion of the crown removed.Second,we assessed stand and tree properties over a 500 m elevation gradient above the villages where we hypothesized that as elevation increases,stand and tree properties should show fewer human impacts.Although extensive branch cutting reduced the live crown,tree height and diameter,compensatory processes likely enabled trees to recover and to add basal area increments(BAIs) similar to those added by trees with full crowns.Trees and stands close to villages showed less growth and lower basal areas,respectively,than stands and trees at intermediate or distant elevations from villages.Areas relatively close to the villages showed considerable effects of human-related disturbances such as branch cutting,grazing,tree and shrub removal,losses of litter,and human and animal trails.Such areas had increased soil erosion and often loss of the ‘A' horizon.Stands close to villages had younger trees,lower stand basal areas,smaller basal area increments,and more stumps.Our results suggest an increasingly vulnerable interface between occupants of these two villages and their surrounding forests.展开更多
Many conflicts are reported in small islands mainly in Eastern region of Indonesia and it is needed to conflict resolution in the forest sector. The research has been conducted on forest conflict in the small island o...Many conflicts are reported in small islands mainly in Eastern region of Indonesia and it is needed to conflict resolution in the forest sector. The research has been conducted on forest conflict in the small island of Yamdena. The aims of the research were: (1) to determine the customary rights of indigenous peoples to the forest area that was claimed as theirs according to the applicable rules and regulations; (2) to study the causes of conflict between indigenous peoples and the logging company; (3) to analyze the policy in the forest resources management on the customary land. This research is qualitative and uses a case study methodology. Data collection methods used include semi-structured interviews, participant observation and focus group discussion (FGD). The results showed that indigenous peoples whose livelihood is highly dependent on the forest were most threatened because of forest exploitation of their traditional land by the logging company. Handling of the conflict potential in the forest resources management in Yamdena island was approached through use of traditional laws, involving all the relevant parties to the conflict. The forest management either by indigenous peoples or the logging company is no longer focused on the timber harvesting but more on conservation aspects.展开更多
The research method in this paper is based on the standard of American Society for Testing andMaterials (ASTM). Planing and sanding are selected to study the machining properties of E. urophylla × E.grandis plant...The research method in this paper is based on the standard of American Society for Testing andMaterials (ASTM). Planing and sanding are selected to study the machining properties of E. urophylla × E.grandis plantation wood. Moreover, the reasons for machining defects are analyzed. The results show E.urophylla × E. grandis planted in south China is a good species with a great potential for solid woodutilization.展开更多
The shortfall of timber resource in China constantly keeps about 150 million m3, which mainly relies on import to fill in the gap. However, Russia, the key timber supply state of China, has encouraged the development ...The shortfall of timber resource in China constantly keeps about 150 million m3, which mainly relies on import to fill in the gap. However, Russia, the key timber supply state of China, has encouraged the development of its national intensive timber processing and therefore the Russian Far East Region started to gradually restrict log export. To this end, this paper analyzes the situation of forest industry and timber production in Russian Far East and discusses the current status and existing problems in timber trade between Russian Far East and China. At the end, the paper presents policy recommendation for future timber trade between Russian Far East and China and views their forestry cooperation prospect.展开更多
Based on the forest resources, supply and demand for timber as well as the demand tendency of timber in China, this article studies how to achieve the balance of supply and demand by self-support and indicates that de...Based on the forest resources, supply and demand for timber as well as the demand tendency of timber in China, this article studies how to achieve the balance of supply and demand by self-support and indicates that developing fast growing forest plantations to get more timber, using timber and forest resources efficiently and economically, enlarging resources of raw materials, exploring and using bio- mass resources for bio-based composites are efficient ways to fill the gap between supply and demand for timber and timber products in China.展开更多
基金This paper was supported by National Natural Science Foundation of China (No. 30400341) and Heilongjiang Provincial Science Foundation (No. C0320)Acknowledgement I thank Dr. YAN Xiu-feng for his help and guidance.
文摘A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings and the allelopathy between the two tree species. Four concentrations (100 g. kg i, 50 g. kg^-1, 25 g. kg^-1 and 12.5 g. kg^-1) were prepared for each kind of extracts. Result showed that the water extracts with low and moderate concentrations accelerated the growth of collar diameter and increased biomass and root/shoot ratio of walnut seedlings. The water extracts from branches and barks with low and moderate concentrations accelerated the height growth of the seedlings, while those from leaves and roots slightly decreased the height growth of seedlings. The fact that application of water extracts of larch improved the growth of Manchurian walnut attributes possibly to the allelopathy between the two tree species.
文摘In a tropical wet montane evergreen forest in the southern peninsular India, the estimated stocking of dead wood is 90 ± 3 stems·ha-1 and the total dead wood volume is 70.7 m3·ha-1. When the logs (downed dead trees more than 10.1 cm in diameter) constitute about 80% of the total deadwood stocking and volume, the rest is by snags (sound and rotting standing dead trees). Since the shola forest trees are characterized by their short stature with low to medium girth, about 89% of the total number of deadwood is of the size ranging from 10.1 cm to 40.0 cm in diameter. The estimated standing dead wood/standing live tree ratio is 0.16 indicating that the forest represents an old stand. Variations observed between logs and snags to change from a given decay class to the higher decay classes in two year period could be attributed to the facts that the logs would be in contact with soil for a relatively longer time and in turn would be in more contact with microorganisms and other decomposing agents.
文摘Rupa Lake is small advancing eutrophic lake covering about 115 ha of the Lekhnath Municipality in Kaski district of western Nepal. The environment around the lake has been improved over a period of 10 years. Conservation practices were initiated by communities including the Rupa Lake Restoration and Fishery Cooperative (RLRFC). As a result, an abundance of non-timber Forest Products (NTFP) has increased considerably. At present, 49 NTFP are available in the lake basin. Some households (HH) i.e 10% has additional income from NTFP. It is an indirect source of food security for local people. They sell NTFP products to generate income. A few households have already started farming of NTFPs. Availability of fodder and fuel wood from community forest has significantly contributed to the livelihoods of people where as wild edible fruits and vegetables have become supplementary for food security. There is yearly food security for 57% of HH with 22% having surplus food. 5% of HH has food security for less than three months where as 19% HHs have food security for more than six months. However, livelihood and nutritional security have improved by fish farming in lake. This lake is most important for the local environment and also helps eco-tourism. The study found that 92% observed the climate change in the form of a rise in temperature (〉 70% HHs); unpredictable rainfall (〉 75% HHs); shifting rainfall (〉 60% HHs); phonological changes (〉 50%). It showed that the lake supports the restoration of natural water capacity, maintain local climate and sound environment by better natural resource management for an environment friendly ecosystem.
基金Under the auspices of National Natural Science Foundation of China (No.30770410,31070384)Autonomous Planned Innovation Project of Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences (No.200905010)
文摘Based on forest inventory data (FID) at sublot level,we estimated the carbon sequestration in forest vegetation of Beijing,China in 2009.In this study,the carbon sequestration in forest vegetation at sublot level was calculated based on net biomass production (ΔB) which was estimated with biomass of each sublot and function relationships between ΔB and biomass.The biomass of forested land was calculated with biomass expansion factors (BEFs) method,while those of shrub land and other forest land types were estimated with biomass,coverage and height of referred shrubs and shrub coverage and height of each sublot.As one of special forested land types,the biomass of economic tree land was calculated with biomass per tree and tree number.The variation of carbon sequestration in forest vegetation with altitude,species and stand age was also investigated in this study.The results indicate that the carbon sequestration in forest vegetation in Beijing is 4.12 × 106 tC/yr,with the average rate of 3.94 tC/(ha·yr).About 56.91% of the total carbon sequestration in forest vegetation is supported by the forest in the plain with an altitude of < 60 m and the low mountainous areas with an altitude from 400 m to 800 m.The carbon sequestration rate in forest vegetation is the highest in the plain area with an altitude of < 60 m and decreased significantly in the transitional area from the low plain to the low mountainous area with an altitude ranging from 200 m to 400 m due to intensive human disturbance.The carbon sequestration of Populus spp.forest and Quercus spp.forest are relatively higher than those of other plant species,accounting for 25.33% of the total.The carbon sequestration in vegetation by the forest of < 40 years amounts to 45.38% of the total.The carbon sequestration rate in forest vegetation peaks at the stand age of 30–40 years.Therefore,it would be crucial for enhancing the capability of carbon sequestration in forest vegetation to protect the forest in Beijing,to limit human disturbance in the transitional area from the plain to the low mountain area,and to foster the newly established open forest.
文摘The phytogeographical system for vegetation classification splits the vegetation in first level types: forest and grasslands. The forest type can be recognized in tropical rain forest and seasonal depending on the environmental conditions. This determines the occurrence of deciduous species in big or small quantity. And the grasslands are Savannah in majority. This work proposed probabilistic methods to classify these vegetation types based on priori occurrence of species. The test was carded out with forest inventory data using ten vegetation fragments in farm of Embrapa and Cascata's park in Sete Lagoas city, Minas Gerais, Brazil. The distribution of species with occurrence in different types was adapted to set theory and Bayes theorem. In this way, it is possible to calculate belonging of species on vegetation types. The results were compared with usual classification. The main contribution of probabilistic methods was to increase the information to classify tree and shrub vegetation inventoried. It is especially recommended for transition regions between vegetation types.
基金Financial support was provided by an Asian Studies Grant to Harrell, NSF - IGERT 0333408the School of Environmental and Forest SciencesUniversity of Washington, Seattle, WA, USA
文摘This paper examines human impact on stands and individual trees of Pinus yunnanensis growing near the small mountain villages of Pianshui and Yangjuan in southwestern Sichuan Province,China.In an effort to assess whether use of these forests was sustainable,we examined the effects of human use in two ways.First,we directly measured the effect of cutting branches,for fuel and fodder,on tree growth.We hypothesized that branch cutting would negatively impact tree growth.We established 12 plots on four hills and compared 14 pairs of trees,one tree in each pair with an apparently full crown and the other with a considerable portion of the crown removed.Second,we assessed stand and tree properties over a 500 m elevation gradient above the villages where we hypothesized that as elevation increases,stand and tree properties should show fewer human impacts.Although extensive branch cutting reduced the live crown,tree height and diameter,compensatory processes likely enabled trees to recover and to add basal area increments(BAIs) similar to those added by trees with full crowns.Trees and stands close to villages showed less growth and lower basal areas,respectively,than stands and trees at intermediate or distant elevations from villages.Areas relatively close to the villages showed considerable effects of human-related disturbances such as branch cutting,grazing,tree and shrub removal,losses of litter,and human and animal trails.Such areas had increased soil erosion and often loss of the ‘A' horizon.Stands close to villages had younger trees,lower stand basal areas,smaller basal area increments,and more stumps.Our results suggest an increasingly vulnerable interface between occupants of these two villages and their surrounding forests.
文摘Many conflicts are reported in small islands mainly in Eastern region of Indonesia and it is needed to conflict resolution in the forest sector. The research has been conducted on forest conflict in the small island of Yamdena. The aims of the research were: (1) to determine the customary rights of indigenous peoples to the forest area that was claimed as theirs according to the applicable rules and regulations; (2) to study the causes of conflict between indigenous peoples and the logging company; (3) to analyze the policy in the forest resources management on the customary land. This research is qualitative and uses a case study methodology. Data collection methods used include semi-structured interviews, participant observation and focus group discussion (FGD). The results showed that indigenous peoples whose livelihood is highly dependent on the forest were most threatened because of forest exploitation of their traditional land by the logging company. Handling of the conflict potential in the forest resources management in Yamdena island was approached through use of traditional laws, involving all the relevant parties to the conflict. The forest management either by indigenous peoples or the logging company is no longer focused on the timber harvesting but more on conservation aspects.
基金the National Basic Research Program of China(973 Program):Ecosystem Services and Ecological Safety of the Major Terrestrial Ecosystems of China(grant number:2009CB421106)National Natural Science Foundation of China(grant number:30670374)the EU 6th Framework Programme for Research,Technological Development and Demonstration,Priority 1.1.6.3 Global Change and Ecosystems(European Commission,DG Research,contract 003874[GPCE])
文摘The research method in this paper is based on the standard of American Society for Testing andMaterials (ASTM). Planing and sanding are selected to study the machining properties of E. urophylla × E.grandis plantation wood. Moreover, the reasons for machining defects are analyzed. The results show E.urophylla × E. grandis planted in south China is a good species with a great potential for solid woodutilization.
基金Supported by National Key Basic Research Plan of China (Grant No.2005CB724801)
文摘The shortfall of timber resource in China constantly keeps about 150 million m3, which mainly relies on import to fill in the gap. However, Russia, the key timber supply state of China, has encouraged the development of its national intensive timber processing and therefore the Russian Far East Region started to gradually restrict log export. To this end, this paper analyzes the situation of forest industry and timber production in Russian Far East and discusses the current status and existing problems in timber trade between Russian Far East and China. At the end, the paper presents policy recommendation for future timber trade between Russian Far East and China and views their forestry cooperation prospect.
文摘Based on the forest resources, supply and demand for timber as well as the demand tendency of timber in China, this article studies how to achieve the balance of supply and demand by self-support and indicates that developing fast growing forest plantations to get more timber, using timber and forest resources efficiently and economically, enlarging resources of raw materials, exploring and using bio- mass resources for bio-based composites are efficient ways to fill the gap between supply and demand for timber and timber products in China.