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1.
Himalayan mountain system is distinguished globally for a rich biodiversity and for its role in regulating the climate of the South Asia.Traditional crop-livestock mixed farming in the Himalaya is highly dependent on forests for fodder and manure prepared from forest leaf litter and livestock excreta. Apart from sustaining farm production, forests provide a variety of other tangible and intangible benefits, which are critical for sustainable livelihood of not only 115 million mountain people, but also many more people living in the adjoining plains. Extension of agricultural landuse coupled with replacement of traditional staple food crops by cash crops and of multipurpose agroforestry trees by fruit trees are widespread changes. Cultivation of Fagopyrum esculentum,Fagopyrum tataricum, Panicum miliaceum, Setaria italica and Pisum arvense has been almost abandoned. Increasing stress on cash crops is driven by a socio-cultural change from subsistence to market economy facilitated by improvement in accessibility and supply of staple food grains at subsidized price by the government. Farmers have gained substantial economic benefits from cash crops. However, loss of agrobiodiversity implies more risks to local livelihood in the events of downfall in market price/demand of cash crops, termination of supply of staple food grains at subsidized price, pest outbreaks in a cash crop dominated homogeneous landscape and abnormal climate years. Indigenous innovations enabling improvement in farm economy by conserving and/enhancing agrobiodiversity do exist, but are highly localized. The changes in agrobiodiversity are such that soil loss and run-off from the croplands have dramatically increased together with increase in local pressure on forests. As farm productivity is maintained with forest-based inputs, continued depletion of forest resources will result in poor economic returns from agriculture to local people,apart from loss of global benefits from Himalayan forests. Interventions including improvement in traditional manure and management of on-farm trees,participatory development of agroforestry in degraded forest lands and policies favoring economic benefits to local people from non-timber forest products could reduce the risks of decline in agricultural biodiversity and associated threats to livelihoods and Himalayan ecosystems.  相似文献   

2.
Vast grasslands are found in the walnut-fruit forest region of southern Kyrgyzstan,Middle Asia.Located above the worldwide unique walnutfruit forests and used for grazing,they play a pivotal role in the mixed mountain agriculture of local farmers.Accordingly,these pastures are subject to an increasing utilization pressure reflecting the changing political and social conditions in the transformation process from a Soviet republic to an independent state.A first detailed analysis of mountain pasture vegetation in the Ferghana Range answers the following questions:What are the main plant community types among Kyrgyzstan’s mountain pastures? What are the main environmental gradients that shape their species composition? Which phytogeographical distribution types are predominant? How does grazing affect community composition and species richness in these grasslands? Species composition was classified by cluster analysis;underlying environmental gradients were explored using DCA.A dataset of 395 relevés was used for classification,and a subset of 79 relevés was used in a DCA to analyze the correlation between vegetation,environment,and grazing impact.The investigated pastures were classified into four distinctive plant communities.The site factors altitude,heat load,inclination and grazing impact were found to be the major determinants of the vegetation pattern.A significant overlap between floristic composition and structural and spatial properties was shown.The majority of the species pool consisted of Middle Asian endemics and Eurosiberian species.However,disturbance-tolerant species played a significant role with respect to species composition and coverage of the herbaceous layer in vast areas of southern Kyrgyzstan’s mountain pastures.In general,an intense grazing impact is clearly reflected by both species composition and structural variables of plant communities.The highly diverse and unique ecosystem is modified by an increasing utilization pressure.In order to maintain vital processes and functioning of this valuable ecosystem-in both economical and ecological terms-,it is indispensable to adopt appropriate pasture management strategies.  相似文献   

3.
Mangrove forests occur extensively in the tropic areas rich in wildlife and other nonforestry resources and provide a wide array of raw materials for livelihood and production processes and have been a major source of income generation and subsistence for the local people.Exploitation of timber, fuel wood, poles, industrial raw material, and many other non-wood products from the mangrove forests give rise to large scale economic activity and income generation. At present, mangrove forests are facing great peril. Reckless exploitation and swampland reclamation result in their gradual degradation. This article deals with the world‘s mangrove forest resources and their benefit to people ; describes the cmrrent status, points out the main causes of the destruction of these forests, presents proposals for protecting mangrove forests, and discusses international cooperation in protecting the world‘s mangrove forests.  相似文献   

4.
Forest ecosystem services and their values in Beijing   总被引：5，自引：3，他引：2  
As the most important ecosystem in Beijing, the forest supports a lot of ecosystem services to local and around communities, which plays a key role in the maintenance of urban ecological security.However, the valuation on the forest ecosystem services based on regional scale could not provide precise and reasonable values for forestry sector management.In this study, we estimated the magnitudes and economic values of the forest ecosystem services in Beijing at sublot level.The economic value of forest ecosystem services in Beijing was estimated to be 19 339.71×10 6 yuan(RMB) in 2004.Among all the ecosystem services indicators we estimated in this study, only fruit, timber and part of the recreation(which only include the tourism income from the forest parks and scenic areas, but not include that from other forest types) were measured in the social economic system.As estimated in this study, more than 82.19% of the economic value of forest ecosystem services could not be measured in the socio-economic statistical system.The importance of forest ecosystem services in Beijing to human welfare was underestimated by the socio-economic system.Therefore, the policies about the eco-compensation of forest ecosystem services should be established to maintain the sustainable supply of the forest ecosystem services in Beijing.  相似文献   

5.
This study analyzed the causes of forest devastation, the characteristics of forest rehabilitation process, and the success factors of reforestation. And it reviewed the management of rehabilitated forest resources and identified the income sources of mountain villages in South Korea. The devastation of forest starting from the early twentieth century was continued to the 1950＇s. The main causes of deforestation were the illegal cutting of trees for fuel and the slash-and-burning agriculture in forest. The success factors of reforestation were the decrease in the dependence on forest of fuel source, strict administration system and national participation. Sustainable forest management could be made possible through the practical use of social issues like public work project for prevention of landslide damages caused by the thinned logs left in the forest. Also it could be possible by making people realize that the public benefit was obtained from forest and the income sources of mountain villages were supplemented by non-timber forest products and tourism. Food and Agriculture Organization indicated Korea as the country that forestation was succeeded in a very short period. Korea seems to be not ordinary because economic growth was accomplished with rehabilitating natural environment. Korean forestation can become a good prototype of combining environmental rehabilitation and economic development.  相似文献   

6.
Wild mushrooms are recognized as important non-wood forest products in mountainous ecosystems, but their real potential for generating rural economies has not been fully evaluated due to the difficulties in obtaining reliable productivity data, minimizing their true potential as contributor to rural economies. Mushroom yield models based on large data series from Pinus forest ecosystems in the region of Catalonia(Spain), combined with data from the Spanish National Forest Inventory allow us to estimate the potential mushroom productivity by forest ecosystems. The results of 24,500 tons/yr of mushrooms of which 16,300 tons are classified as edible and 7,900 tons are commonly marketed demonstrate the importance of mushroom productions in Catalonian pine forests, mostly located in mountainous areas where the development of agricultural activities is limited. Economic mushroom value is estimated at 48 million € for the edible mushroom and 32 million € for those corresponding to marketable yields, confirming the potential of this non-wood forest product. These production results and corresponding economic values provide a basis for the incorporation of wild mushrooms as significant non-wood forest products in the development of forest policies in mountainous areas.  相似文献   

7.
Community participation in forest resource management in Nepal   总被引：2，自引：1，他引：1  
Livelihood of the people in Nepal hills depends much upon forest resources in addition to farming as forest plays a critical role in the well being of the farming households where access to alternative sources, such as energy for cooking, nutrition for animals, materials for fertilizer and constructing materials for shelter, are limited. Thus, the well being of the people in the hills is directly affected by the management of these forest resources. This issue was addressed in this paper by examining the forest resource management practices and its effect on well being of rural people in two different stages in a village lying in the steep hill of Mahabharat Range in the southern hills of Kathmandu valley, Lalitpur District. The main ethnic/caste groups in the villageare Brahmin/Chhetri (high Hindu caste),Magar/Tamang (Tibeto Burmans) and Kami (occupational caste: cobbler). Currently there are four community forest users groups, with mixed ethnic membership, organized to manage the forest resources. The endowments, weak institutional settings, before 1990 helped the Bhramins, Magars and Tamangs to get access into the private forest endowment, which made them easy to get access to the forest resources, mainly fuel wood, fodder and timber in 1990 and enhanced their well beings. But the socially backward Kami could not get benefit from the institutions that existed during that time and had less chance to enhance their well beings. After the set up of different endowments during late 199os, i.e.,hand over of forest management to users groups in line with the concept of community forest,environment to use the forest resources became better for all the groups, along with the management of the forest. This enhanced the well beings of all the groups in the study village. However, the ability of Kami to use the forest resources to enhance their well beings was still lacking behind. The reason was partially due to the difference in endowments carried over from the endowments before 199o, and partly due to their occupational work and location of their settlements.  相似文献   

8.
Community-based natural resource management in northeast India has a long history. Indigenous knowledge and adaptation are the collective information, with improvement from generation to generation. The expectation is that under community control, local expertise on biodiversity will play a significant role in natural resource management through traditional practices. This paper discusses the characteristics and application of the traditional ecological knowledge of aboriginal peoples in northeast India and its role in natural resource management. Examples are provided in two different eco-cultural landscapes, i.e., Demazong (the Buddhist eco-cultural landscape in Sikkim Himalaya) and the Apatani eco-cultural landscape in Arunachal Pradesh, which illustrate the utility value of traditional ecological knowledge in sustainable natural resource management. Both eco-cultural landscapes are indeed very complex and highly evolved systems with high levels of economic and ecological efficiencies. The paper concludes that traditional ecological knowledge systems and institutions could serve as entry points into the sustainable utilization and management of natural resources. This could be achieved through the exploration of the cultural practices of the local people and integrating useful aspects into the modern natural resource management expertise. With rapidly depleting biodiversity in the developing tropic regions, there is a greater utilization today than ever before of the value of respecting the "Sacred" as a tool towards better conservation of natural resources.  相似文献   

9.
The paper scrutinizes that the changes in any sub-system(i.e.agriculture,livestock and forest) have direct impact on biophysical and social processes in village ecosystem of the central Himalayan region.In view of this,we studied the changes in spatial patterns of agricultural land use and dependency of agroecosystem on forest and animal husbandry over a period of two decades.Based on data analysis it was found that the cultivation of some traditional crops has either been abandoned in the area or declined by 25%-85% due to introduction of cash crops viz.,potato,kidney bean and apple farming with acreage increased up to 51%-72% in the last three decades.Livestock population of different categories has declined drastically by 17%-75%,and has resulted shortage of farmyard manure,deterioration of soil quality and fertility which leads to un-sustainability of agriculture system.The changes in agrobiodiversity have led to the dramatic increase in soil loss and runoff from the croplands together with the increase pressure on forests.The economic evaluation of each crop showed higher monetary benefit from cash crops as compared to traditional crops.Among all the evaluated crops,the monetary output/input ratio was found highest(3.04) for kidney bean and lowest(1.26) for paddy.Changes in land use and management have improved household income but at the cost of forest degradation,less productive animal husbandry and loss of agrodiversity in the region.Therefore,there is an urgent need to bring desirable changes in agricultural policy,research,land use and efficient management of the resources for maintaining sustainability in agro and Himalayan forest ecosystem.  相似文献   

10.
Close-to-nature forest management has been proposed as an effective method for improving the quality of plantation forests. Knowledge of spatial distribution patterns, structure, and succession trajectories in natural forests can provide guidelines for the establishment of close-to-nature forest plantations. Such knowledge is lacking in natural spruce(Picea crassifolia) forests in the Qilian Mountains of China, impeding the establishment of production forests. We conducted a case study in the Qilian Mountains to analyze the relationships between the naturally-formed forest patches and terrain factors, spatial heterogeneity of stand characteristics, and stand structure following harvesting disturbance. Our results suggested that spruce plantations will be effective on the N, NE, and NW slopes, at elevations between 2700 and 3300 m, and on slopes ranging from 15° to 45°. Further, planted forest patches should occupy 64% of the slope area on semi-shady slopes(NE, NW). Spatial patterns in the studied forest exhibited a strong scale-effect, and an area of 0.25 ha could be used as the most efficient plot scale for the management of spruce plantations. Partial logging is an effective method for the conversion of spruce planted forests into nearnatural forests, and the intensity of partial logging can be determined from the negative exponential function relationship between stand density and DBH. Our results provided critical information for the development of spruce plantations and conversion of existing plantations.  相似文献   

11.
IntroductionThe mountain forests of South Kyrgyzstan have a long history of human influence. The political and socio-economic conditions prevailing in the region have changed dramatically several times over the last century and have played animportant role in forest policy, management and use. To highlight the human-environment relationship, I have chosen here to use a political ecology approach as conceptual framework (cf. Bryant & Bailey 1997, Bryant 1998, Blaikie 1999). In this approach,…  相似文献   

12.
Enhancing forest carbon(C) storage is recognized as one of the most economic and green approaches to offsetting anthropogenic CO_2 emissions. However, experimental evidence for C sequestration potential(C_(sp)) in China's forest ecosystems and its spatial patterns remain unclear, although a deep understanding is essential for policy-makers making decisions on reforestation. Here, we surveyed the literature from 2004 to 2014 to obtain C density data on forest ecosystems in China and used mature forests as a reference to explore C_(sp). The results showed that the C densities of vegetation and soil(0–100 cm) in China's forest ecosystems were about 69.23 Mg C/ha and 116.52 Mg C/ha, respectively. In mature forests, the C_(sp) of vegetation and soil are expected to increase to 129.26 Mg C/ha(87.1%) and 154.39 Mg C/ha(32.4%) in the coming decades, respectively. Moreover, the potential increase of C storage in vegetation(10.81 Pg C) is estimated at approximately twice that of soil(5.01 Pg C). Higher C_(sp) may occur in the subtropical humid regions and policy-makers should pay particular attention to the development of new reforestation strategies for these areas. In addition to soil nutrients and environment, climate was an important factor influencing the spatial patterns of C density in forest ecosystems in China. Interestingly, climate influenced the spatial patterns of vegetation and soil C density via different routes, having a positive effect on vegetation C density and a negative effect on soil C density. This estimation of the potential for increasing forest C storage provided new insights into the vital roles of China's forest ecosystems in future C sequestration. More importantly, our findings emphasize that climate constraints on forest C sequestration should be considered in reforestation strategies in China because the effects of climate were the opposite for spatial patterns of C density in vegetation and soil.Enhancing forest carbon(C) storage is recognized as one of the most economic and green approaches to offsetting anthropogenic CO2 emissions. However, experimental evidence for C sequestration potential(Csp) in China's forest ecosystems and its spatial patterns remain unclear, although a deep understanding is essential for policy-makers making decisions on reforestation. Here, we surveyed the literature from 2004 to 2014 to obtain C density data on forest ecosystems in China and used mature forests as a reference to explore Csp. The results showed that the C densities of vegetation and soil(0–100 cm) in China's forest ecosystems were about 69.23 Mg C/ha and 116.52 Mg C/ha, respectively. In mature forests, the Csp of vegetation and soil are expected to increase to 129.26 Mg C/ha(87.1%) and 154.39 Mg C/ha(32.4%) in the coming decades, respectively. Moreover, the potential increase of C storage in vegetation(10.81 Pg C) is estimated at approximately twice that of soil(5.01 Pg C). Higher Csp may occur in the subtropical humid regions and policy-makers should pay particular attention to the development of new reforestation strategies for these areas. In addition to soil nutrients and environment, climate was an important factor influencing the spatial patterns of C density in forest ecosystems in China. Interestingly, climate influenced the spatial patterns of vegetation and soil C density via different routes, having a positive effect on vegetation C density and a negative effect on soil C density. This estimation of the potential for increasing forest C storage provided new insights into the vital roles of China's forest ecosystems in future C sequestration. More importantly, our findings emphasize that climate constraints on forest C sequestration should be considered in reforestation strategies in China because the effects of climate were the opposite for spatial patterns of C density in vegetation and soil.  相似文献   

13.
In order to realize the significance of oak forests for ecology and economy of the Himalayan region,the present study attempts to objectively characterize disturbance intensities and their impacts on compositional features of identified Oak forests, i.e.Banj-oak(Quercus leucotrichophora A.Camus), Tilonj-oak(Q.floribunda Lindley)and Kharsu-oak(Q. semecarpifolia J.E.Smith)in west Himalaya. Amongst studied forests,Q.leucotrichophora and Q. semecarpifolia forests exhibited high sensitivity towards disturbance intensities.In both forests, increasing level of disturbance significantly lowered tree density,dominance and natural recruitment (seedling and sapling density).Q.floribunda forests, however,appeared relatively more resilient to anthropogenic disturbances.Amongst studied oak forests,Q.semecarpifolia forests with overall poor natural regeneration are in a most critically endangered demographic state.However,a slightly improved regeneration(i.e.,seedling density)in moderately disturbed plots is indicative that such plots may be utilized most suitably for in situ revival of these forests.Effect of disturbance intensities on tree population is an important subject for forest ecology and management and the present study highlights a need for adopting different management strategies across disturbance intensities in diverse oak forests of west Himalaya.  相似文献   

14.
Changes in permanent sample plots in the lowland,submontane and montane forests on Mount Cameroon(4,095 m above sea level),an active volcano,are described for 15 years from 1989 to 2004.Throughout the study period,the stocking level of trees with a diameter at breast height(DBH) ≥ 10 cm in the three forests were lower than in pan-tropical stands suggesting a significant impact of volcanic and human-related activities on the vegetation communities on the mountain.Annual mortality rates in the submontane and montane forests were consistent with those reported for comparable altitudinal ranges in the Blue Mountains of Jamaica.The annual mortality rate was higher in the lowland forest than other lowland sites included.Divergence between recruitment and mortality rates was large suggesting that the three vegetation communities have not reached their climax.The seven-year difference in half-life of large trees(with a DBH ≥ 50 cm) in the submontane and montane forests suggests an altitudinal effect on turnover of larger trees that in turn contributes to the frequent small stature of high altitude forests.There was little evidence of an altitudinal effect on species turnover and growth rate.This finding supports generalizations about the zero effect of growth on the stature of high altitude trees.Understanding forest dynamics is crucially important in the management of tropical montane environmentsand in this instance particularly so given the recent creation of the Mount Cameroon National Park.  相似文献   

15.
Sustainable world heritage management represents an approach for managing the resources of a property by integrating environmental, economic, and social issues. It aims to provide sustainable benefits for future generations, while protect the property and minimize the possible adverse social, economic and environmental impacts. Indicators of sustainable development, which summarize information for decision-making, are invaluable to learn the efficiency and effectiveness of property management. Scientists in many fields devised several conceptual models of environmental statistics and indicators, of which, DPSIR (Driving forces – Pressure – State – Impact – Response) is thought to be the best available one in identifying and developing indicators of sustainable development. Based on the DPSIR conceptual model and indicator selection criteria, the present paper proposed a methodology framework for selecting indicators to assess the sustainable development of a natural heritage site. The proposed framework included a multi-level hierarchical structure for various indicators and indexes, a modified DPSIR frame to identify key issues in property management and a set of indicators for evaluating the sustainability in Sichuan Giant Panda Sanctuaries.  相似文献   

16.
Rapid urbanization has led to dramatic changes in urban forest structures and functions, and consequently affects carbon(C) storage in cities. In this study, field surveys were combined with high resolution images to investigate the variability of C storage of urban forests in Changchun, Northeast China. The main objectives of this study were to quantify the C storage of urban forests in Changchun City, Northeast China and understand the effects of forest type and urbanization on C storage of urban forests. The results showed that the mean C density and the total C storage of urban forests in Changchun were 4.41 kg/m2 and 4.74 × 108 kg, respectively. There were significant differences in C density among urban forest types. Landscape and relaxation forest(LF) had the highest C density with 5.41 kg/m2, while production and management forest(PF) had the lowest C density with 1.46 kg/m2. These differences demonstrate that urban forest type is an important factor needed to be considered when the C storage is accurately estimated. Further findings revealed significant differences in different gradients of urbanization, and the mean C density decreased from the first ring(6.99 kg/m2) to the fourth ring(2.87 kg/m2). The total C storage increased from the first ring to the third ring. These results indicate that C storage by urban forests will be significantly changed during the process of urbanization. The results can provide insights for decision-makers and urban planners to better understand the effects of forest type and urbanization on C storage of urban forests in Changchun, and make better management plans for urban forests.  相似文献   

17.
It is widely accepted that global warming, which results from the increase of carbon dioxide(CO2) in the atmosphere, has a negative impact on human beings. Forests are the largest terrestrial ecosystem and play an important role in carbon sequestration. Many studies have documented that a mixed-species forest can sequester more carbon than single species forests, depending on the site conditions. Therefore, uneven-aged mixed-species forest management has been receiving more and more attention. In 2008, an experiment with five silvicultural models for Pinus massoniana(Chinese red pine) plantation, i.e., four transformation treatments(A1-A4) and one control treatment(A5) was conducted in the Experimental Center of Tropical Forestry of Chinese Academy of Forestry in Pingxiang City, in southwestern Guangxi Zhuang Autonomous Region, southern China. The four transformation treatments(A1-A4) enriched Castanopsis hystrix, Manglietia glance, Erythrophleum fordii and Quercus griffithii with differed richness and composition after thinning(removed 70% of trees), while no silvicultural treatment was used in the control treatment A5. In this study, we compared the carbon sequestration capacity of these five silvicultural models based on periodic annual increment and growth rate. Our results indicated that all the transformation treatments performed significantly better in carbon sequestration than the control treatment. A significant difference was also observed amongst the transformation treatments. Moreover, the transformation treatment A1 with enrichment species Castanopsis hystrix(350 trees·ha^-1) and Manglietia glance(350 trees·ha^-1) was determined to be the optimal model for maximum carbon sequestration because of its high tree-level growth rate and high economic value of enriched plantings, which could be popularized in other places. Our results further confirmed that management using mixed-species forests is a better approach to combat climate change than using monoculture forests.  相似文献   

18.
Based on the fractal theory, the spatial structure of China＇s vegetation has been analyzed quantitatively in this paper. Some conclusions are drawn as the following. 1） The relationships between size and frequency of patch area and patch shape index exist objectively for China＇s vegetation. 2） The relationships between perimeter and area exist objectively for China＇s vegetation. 3） The fractal dimension of evergreen needleleaf forests on mountains in subtropical and tropical zones is the largest, while the smallest for deciduous broadleafand evergreen needleleaf mixed forests in temperate zone, reflecting the most complex spatial structure for evergreen needleleaf forests on mountains in subtropical and tropical zones and the simplest for deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone. 4） The fractal dimensions of China＇s vegetation types tend to decrease from thc subtropics to both sides. 5） The stability of spatial structure of deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone is the largest, while the smallest for double-cropping rice, or double-cropping rice and temperate-like grain, and tropical evergreen economic tree plantations and orchards, reflecting the steadiest for deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone and the most unstable for double-cropping rice, or double-cropping rice and temperate-like grain, and tropical evergreen economic tree plantations and orchards in spatial structure. 6） The stability of spatial structure of China＇s vegetation tends to decrease from the temperate zone to both sides, it is significantly pertinent to understand the formation, evolution, dynamics and complexity rule of ecosystem of vegetation.  相似文献   

19.
Red beds cover approximately 9.5% of China, and are home to approximately 144 million people. In total, 83% of these lands are distributed in humid regions making it an important part of research on red bed soil erosion in China in these areas. This paper presents the main types of land degradation in red bed landscapes and the status of current soil erosion in a typical red bed basin, the Nanxiong Basin located in the north of Guangdong Province, China, and establishes the connection between management strategies and regional economic development in humid red bed regions of China. The soil erosive modulus was calculated in the Nanxiong Basin by using RUSLE(The Revised Universal Soil Loss Equation). The results of overlapping analyses demonstrated that appropriate measures, such as the Return Farmland to Forests initiative, should be taken at the junction of central red bed areas and mountainous areas in order to mitigate current soil erosion. Two examples are presented to demonstrate this: the tourism development in Mt. Danxiashan, a noted scenic mountainous area near Nanxiong Basin, and the land degradation mitigation in the Nanxiong Basin. Both examples promote local economic growth while simultaneously protecting the environment. A.stakeholder‘ strategy is pursued at Mt. Danxiashan,which can help residents to understand their positive effects on the environment as well as increase theirincome. The second example, in Nanxiong City,showcases how local farmers became stakeholders by implementing contract responsibility and self-support systems for economic forests and terraced land in the 1980s.  相似文献   

20.
Deforestation and associated ecological disturbances are the issues of global concern.Researchers have investigated a number of driving forces which accelerate the rate of deforestation at local and regional levels.These include poverty,population growth,market demand and prices,political instability,agricultural expansion and changes in property right and ownership regimes.This paper seeks to explore the impacts of population growth,changing tenure system and other socioeconomic factors on the forest cover of Roghani Valley,located in Hindu Raj Mountains,Northern Pakistan.The present study is mainly based on information collected through participatory observation,selfadministered interviews and questionnaire survey.Geographical Information System（GIS） database is also used for mapping and quantification.The results reveal that in the past three to four decades the study area has been subjected to severe deforestation and about half of the forest area has been converted into barren land.Thus,the area under natural forests decreased from 2099 to 1444 hectares in four decades.This large-scale deforestation is attributed to both proximate and under lying causes particularly traditional land tenure system and demographic development.Consequently,forest resources have been degraded and a number of plant species have disappeared from the forests of the study area while several others are in the process of disappearance.  相似文献   

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