Background: Around 2000 plant species occur naturally in Lorestan Province of which 250 species are medicinal and myrtle is one of them. Myrtle is a shrub whose leaves and fruits have medicinal value and thus, if man...Background: Around 2000 plant species occur naturally in Lorestan Province of which 250 species are medicinal and myrtle is one of them. Myrtle is a shrub whose leaves and fruits have medicinal value and thus, if managed and harvested properly, could produce sustained economic benefits. In recent years, however, over half of the myrtle site areas was destroyed, due to inappropriate management and excessive harvesting practices. Thus, coming up with a practical harvesting approach along with identifying those factors damaging the sites, seems to be very crucial. Methods: In our investigation, we calculated the conservation value per hectare of myrtle in the Dooreh forest area in Lorestan Province. Using the Contingent Valuation (CV) and Double Bounded Dichotomous Choice (DBDC) methods, we determined the willingness to pay (VVTP) for myrtle conservation. The VVTP was estimated with a Iogit model for which indices were obtained based on a maximum precision criterion. Results: The results showed that 86.67 per cent of people were willing to pay for the conservation of these myrtle sites. Average monthly WTP per family was calculated as $0.79. The annual conservation value in terms of WTP for the preservation of the myrtle sites in Dooreh was estimated as $102,525. Among the variables of the model presented, education had a positive impact, while the amount proposed for payment and family size had a negative impact on the WTP. Conclusions: Our estimate of the value of myrtle conservation should provide justification for policy makers and decision making bodies of natural resources to implement policies in order to conserve the natural sites of this species more effectively.展开更多
High conservation value forest(HCVF) theory has aroused wide concerns among related forestry sectors in China,but the zoning and identification of HCVF only have been implemented in a few forest management units(FMUs)...High conservation value forest(HCVF) theory has aroused wide concerns among related forestry sectors in China,but the zoning and identification of HCVF only have been implemented in a few forest management units(FMUs). As there is no quantitative indicator for identifying and zoning HCVF in China,most FMUs are unable to have an exact zoning result. This paper introduced the concepts of HCVF and ecological forest,and compared their similarities and differences in terms of identification criteria,zoning methods and application scope. With four Chinese FMUs as case studies,some suggestions were proposed for establishing a zoning scheme of HCVF so as to promote the development of HCVF in China.展开更多
By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were ...By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were respectively calculated.The tree species structure and the coverage degree of every kind of forest vegetation were investigated,and the characteristics of forest vegetation were analyzed.The results showed that the soil conservation amount of forest in Fuxian Lake basin was 137.50×106 t/a,and the soil conservation value was 622.30×106 yuan/a.Moreover,the water source conservation value was 506.84×106 yuan/a.展开更多
In general, coastal habitat conditions are extremely harsh, with the ecological equilibrium inextric- ably related to the plant community. Understanding the natural vegetation features of a coastal zone with little hu...In general, coastal habitat conditions are extremely harsh, with the ecological equilibrium inextric- ably related to the plant community. Understanding the natural vegetation features of a coastal zone with little human disturbance could provide a reference for future vegetation restoration and ecosystem maintenance ser- vices. In this study, the vegetation patterns of Wangzi Shell Ridge Island in the Yellow River Delta were investigated. A total of 35 taxa of vascular plants were documented, representing 15 families and 33 genera (of which most were mono-specific). Surveys identified only one to eight taxa in each plot. From sea to land, the vegetation showed a typical zonal distribution pattern. There was a correlation between the landform and important factors that influenced the plants including soil factors and distance from the sea. Thus, the taxa distribution and vegetation had a significant correlation with landform. The dune crest, backdune and interdune lowlands were areas with weak storm surges and were the important locations for the taxa to be become established. Plants along the high-tide line formed important defenses from large waves and high winds. The significant protection provided a suitable living environment for many organisms with high medicinal value. Special attention and protection could be provided to this area by reducing the use of the beach road and enclosing the complete section from sea to land with a protective fence. In addition, vegetation protection and restoration on Shell Ridge Island would aid in the formulation and implementation of reintroduction strate- gies for similar vegetation in similar habitats.展开更多
We propose a numerical solution to incorporate in the simulation of a system of conservation laws boundary conditions that come from a microscopic modeling in the small mean free path regime.The typical example we dis...We propose a numerical solution to incorporate in the simulation of a system of conservation laws boundary conditions that come from a microscopic modeling in the small mean free path regime.The typical example we discuss is the derivation of the Euler system from the BGK equation.The boundary condition relies on the analysis of boundary layers formation that accounts from the fact that the incoming kinetic flux might be far from the thermodynamic equilibrium.展开更多
文摘Background: Around 2000 plant species occur naturally in Lorestan Province of which 250 species are medicinal and myrtle is one of them. Myrtle is a shrub whose leaves and fruits have medicinal value and thus, if managed and harvested properly, could produce sustained economic benefits. In recent years, however, over half of the myrtle site areas was destroyed, due to inappropriate management and excessive harvesting practices. Thus, coming up with a practical harvesting approach along with identifying those factors damaging the sites, seems to be very crucial. Methods: In our investigation, we calculated the conservation value per hectare of myrtle in the Dooreh forest area in Lorestan Province. Using the Contingent Valuation (CV) and Double Bounded Dichotomous Choice (DBDC) methods, we determined the willingness to pay (VVTP) for myrtle conservation. The VVTP was estimated with a Iogit model for which indices were obtained based on a maximum precision criterion. Results: The results showed that 86.67 per cent of people were willing to pay for the conservation of these myrtle sites. Average monthly WTP per family was calculated as $0.79. The annual conservation value in terms of WTP for the preservation of the myrtle sites in Dooreh was estimated as $102,525. Among the variables of the model presented, education had a positive impact, while the amount proposed for payment and family size had a negative impact on the WTP. Conclusions: Our estimate of the value of myrtle conservation should provide justification for policy makers and decision making bodies of natural resources to implement policies in order to conserve the natural sites of this species more effectively.
基金Sponsored by Forest Certifi cation Key Technology and Certifi cation Mode Introduction-"948"Project of the State Forestry Administration
文摘High conservation value forest(HCVF) theory has aroused wide concerns among related forestry sectors in China,but the zoning and identification of HCVF only have been implemented in a few forest management units(FMUs). As there is no quantitative indicator for identifying and zoning HCVF in China,most FMUs are unable to have an exact zoning result. This paper introduced the concepts of HCVF and ecological forest,and compared their similarities and differences in terms of identification criteria,zoning methods and application scope. With four Chinese FMUs as case studies,some suggestions were proposed for establishing a zoning scheme of HCVF so as to promote the development of HCVF in China.
基金Supported by Yuxi Forest Resource Planning Design Investigation Project in Yunnan Province
文摘By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were respectively calculated.The tree species structure and the coverage degree of every kind of forest vegetation were investigated,and the characteristics of forest vegetation were analyzed.The results showed that the soil conservation amount of forest in Fuxian Lake basin was 137.50×106 t/a,and the soil conservation value was 622.30×106 yuan/a.Moreover,the water source conservation value was 506.84×106 yuan/a.
文摘In general, coastal habitat conditions are extremely harsh, with the ecological equilibrium inextric- ably related to the plant community. Understanding the natural vegetation features of a coastal zone with little human disturbance could provide a reference for future vegetation restoration and ecosystem maintenance ser- vices. In this study, the vegetation patterns of Wangzi Shell Ridge Island in the Yellow River Delta were investigated. A total of 35 taxa of vascular plants were documented, representing 15 families and 33 genera (of which most were mono-specific). Surveys identified only one to eight taxa in each plot. From sea to land, the vegetation showed a typical zonal distribution pattern. There was a correlation between the landform and important factors that influenced the plants including soil factors and distance from the sea. Thus, the taxa distribution and vegetation had a significant correlation with landform. The dune crest, backdune and interdune lowlands were areas with weak storm surges and were the important locations for the taxa to be become established. Plants along the high-tide line formed important defenses from large waves and high winds. The significant protection provided a suitable living environment for many organisms with high medicinal value. Special attention and protection could be provided to this area by reducing the use of the beach road and enclosing the complete section from sea to land with a protective fence. In addition, vegetation protection and restoration on Shell Ridge Island would aid in the formulation and implementation of reintroduction strate- gies for similar vegetation in similar habitats.
基金This work is supported by Thales Alenia Space.We are gratefully indebted to J.-F.Coulombel,F.GolseK.Aoki for many useful advices concerning this work and for their kind encouragements。
文摘We propose a numerical solution to incorporate in the simulation of a system of conservation laws boundary conditions that come from a microscopic modeling in the small mean free path regime.The typical example we discuss is the derivation of the Euler system from the BGK equation.The boundary condition relies on the analysis of boundary layers formation that accounts from the fact that the incoming kinetic flux might be far from the thermodynamic equilibrium.