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1.
Biomass plays a vital role in the energy supply of many developing countries. It is the major energy source for the rural population of Nepal, where 70 % of the total energy is derived from woody plant biomass in the form of fuelwood. The main aim of this study is to describe the fuelwood consumption pattern and the role of community forests and trees on private farmland in biomass supply to rural households in Nepal. The study investigates whether demography and socioeconomic attributes of households affect fuelwood consumption. A household survey was conducted, along with measurements of fuelwood mass for six community forest user groups in Dolakha district of Nepal. Average daily household fuelwood consumption was estimated to be 8.4 kg, giving a mean annual consumption of 3060 kg per household. Per capita fuelwood consumption per day was found to be 1.7 kg. Total fuelwood consumption of households is significantly correlated with household size, ownership of cultivated irrigated terraces and number of livestock per household, and negatively significantly correlated with ownership of cultivated rain-fed terraces. Fuelwood consumption varies significantly between seasons. Among various sources of biomass energy, fuelwood from community forests contributes 23 % and trees on private farmland contribute 12 %. The rest is provided from other biomass sources, including the remains of fodder collected from private farmland vegetation, wood previously used for fences and trellises in private farmland, crop residues, and purchased fuelwood.  相似文献   

2.
One of the features of the forest dwellers in the Zagros region of Iran is their dependence on non-timber forest products (NTFPs). These products can play an important role in the livelihood of households located in the forest. The present study aims to determine the most important sources of forest dwellers’ incomes in the northern Zagros in terms of three income groups (lower, middle, and higher), to assess how changes in income are related to types of NTFPs harvested, and to investigate the most significant socio-economic factors determining absolute and relative household revenue from NTFPs. Income in higher- and middle-income groups come predominantly from border trade between Iran and Iraq, comprising 50 and 44 % of relative income, respectively. The main source of income for the lower-income group is remittance and government interest (such as cash subsidies), comprising 31 % of total household annual income. The relative income from NTFPs depends on the income group, varying between 10 and 21 %. Relative income from NTFPs (such as oak acorns, firewood, Gazoo, and Mazooj) for lower-income households is significantly higher than in middle- and higher-income households (p < 0.05). Feed used for grazing livestock in the forest is the most important type of NTFPs in this area, and its benefit in the higher-income group is significantly higher than that for groups with middle and lower income. A similar result is achieved for tree fodder. Relative income from the NTFPs is positively related to number of household members and negatively related to the average education of adult members of the household, the relative income from border trade, and the relative income from agriculture. Our results support our hypothesis that if there is access to other sources of income for forest dwellers, their dependence on forests would be reduced.  相似文献   

3.
We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability: economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types, tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas (especially in settlement and agricultural areas), forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches.  相似文献   

4.
The present study was conducted on the Van Gujjar tribe inhabiting a sub-Himalayan tract in the North Western Himalayas of Uttarakhand State,India.The Van Gujjars have been practicing transmigration over hundreds of years.They migrate each year with their households and livestock between summer and winter pastures.A few years ago with the announcement of the establishment of the Rajaji National Park,the tribe has been forced out of the forest area and rehabilitated outside the park,which has affected their lifestyle.The newly established rehabilitation colony in the Gandikhata area of Haridwar District of Uttarakhand State was taken as a case study.The aims of the present study were to understand and evaluate the socio-economic status of the Van Gujjars in their newly established rehabilitation colony,the utilization pattern of forest resources by the tribe and their relative preference for selective trees for various uses.A total of 176 households were interviewed (giving equal weight to all economic classes and family every size) by using pre-structured questionnaires.The education level was very low (12.9%) and the average income per household was recorded as Rs.36000 (approximately $ 803) per year.The major source of income was dairy production (80.6%) followed by labor employment (13.9%),NTFPs (4.2%) and agricultural production (1.4%).More than 90% of fuel wood and fodder is extracted from the forest.The average fuel wood and fodder consumptions per household per day were recorded as 25.86 and 21.58 kg,respectively.A total of 35 species of cultivated plants and 89 species of wild plants were found to be utilized as food sources.Selectively 25 wild tree species are well known as being used by the Van Gujjars as fodder,fuel wood,agricultural implements,household articles,dye,medicine,fiber and other products.According to their utility value,the most preferred and useful tree species is Ougeinia oojeinensis,followed by Terminalia alata,Bombax ceiba,Shorea robusta and Dalbergia sissoo.  相似文献   

5.
黑龙江省是我国最大的国有林区之一,由于多年来的不合理采伐,已使森林可采资源枯竭,大力发展非林替代产业,建立以非林替代产业为经济格局将成为林区经济发展的必然趋势.  相似文献   

6.
江汉平原杨树林下土壤肥力因子的关联性研究   总被引:1,自引:0,他引:1  
通过对土壤酶活性、土壤微生物数量和土壤养分的分析,研究江汉平原上游10个县(市)杨树林下土壤肥力因子之间时空变化及其相互关系。结果表明:无论是林下相对于林外,还是生长季相对于落叶季,细菌数量与磷酸酶活性、真菌数量与蛋白酶活性总是正相关;而在杨树的生长季节,土壤AA含量与各类微生物数量均呈正相关;土壤NO3--N、有效Ca含量与各类微生物数量均呈负相关;Mg/K与真菌数量显著正相关;土壤NO3--N含量与有效B含量呈极显著正相关;有效Ca含量与有效Mg含量呈显著正相关,与Mg/K呈极显著正相关。  相似文献   

7.
Most Nepalese rural households adopt diversified strategies of income generation and use products directly collected from forests. To analyse the influence of livelihood strategy on forest product utilisation, a survey of 336 rural households in lowland Nepal was conducted. Four livelihood strategies were identified by means of a Principal Component Analysis based on income variables, followed by hierarchical cluster analysis. Two livelihood strategies are assigned to on-farm activities and two to off-farm activities. The off-farm based strategies were found to result in higher household incomes. To test for differences across the livelihood strategies, additional socio-demographic variables, physical assets and location information have been analysed using ANOVA. The forest product utilisation behaviour of the households differs significantly between livelihood strategies. The households adopting a subsistence-based strategy collect the most forest products while achieving the lowest total income. However, a general influence of the total household income on the forest utilisation intensity is not confirmed. Households receiving remittances from abroad achieve the highest incomes but still collect forest products. The group of most forest-dependent households is mainly characterised by living near the forest and far from city centres with commodity and labour markets, and by having low education and a young head of household. The households relying mainly on private business income have the lowest forest product utilisation and are characterised by the highest education, proximity to markets and greatest area of agricultural land.  相似文献   

8.
Forest pasturing of livestock in Norway: effects on spruce regeneration   总被引:1,自引:0,他引:1  
Forest pasturing of free-roaming livestock is a common practice in many parts of the world, but knowledge on how it affects tree regeneration in boreal forests is lacking. We mapped tree density, livestock site use and accumulated damage to young trees of commercial interest(Norway spruce, Picea abies L. Karst.) on 56 clearcuts inside and outside a fenced forest area used for livestock pasturing in Ringsaker, Norway. Inside the fence 56±1.8% of spruce trees were damaged compared to 37±3.4% outside. Proportion of damaged spruce trees was positively related to cattle use of the clearcut, but not so for sheep. On the most intensively used clearcuts, four out of five trees were damaged. The density of deciduous trees was five times lower inside compared to outside of the fence(varying with plant species). While livestock grazing may reduce resource competition in favour of spruce, the current animal density clearly is impeding forest regeneration in the study area.  相似文献   

9.
We analyse the relationships between the main Cervidae [moose (Alces alces), red deer (Cervus elaphus) and roe deer (Capreolus capreolus)] species and a complex of environmental factors in an extensive fragmented landscape of Central Lithuania. The highest determining positive influence on moose density was the proportions of wet forest sites. In forest complexes with fewer proportions of wet sites, the most important factor was the total forest area. The proportion of shrub cover, upland and dense undergrowth area, and road density also has significant effect on moose density. The total area of forest complexes has the highest determining positive influence on red deer density. The highest density of red deer was calculated in large forest complexes (>2,745 ha) with a <17.6 % proportion of pine and <36.5 % of deciduous forests. Other significant factors were core area, road density and urbanization level. Forest edge density has the highest influence on the roe deer populations. The highest density of roe deer was recorded on forest areas with >51 m ha?1 of edges in wet forest (>25.4 %) dominating areas. The proportion of deciduous, coniferous mixed and pine forest, also shrub and density of edges also had significant effect.  相似文献   

10.
In Peru, a new forest reform process laid the foundation for the establishment of a large sector of private small and medium-sized forest enterprises to practice responsible forest management. This paper analyzes the influence of a newly established concession system on forest landscape change. Specifically, the paper examines whether the concession system promoted and increased land-cover changes and changed fragmentation patterns between 2001 and 2010. Classified Landsat images at 2-year intervals from 2001 to 2003 and 2006 to 2010 were used to examine trajectories in forest, non-forest and regrowth areas. Non-linear changes were found to have occurred in each of the forest classes. Changes in fragmentation varied in size, density, aggregation and configuration over the study period. Forest reforms account for changes in specific land-cover classes through pattern dynamics within timber concessions. However, not all results relate to landscape pattern metrics. Although new forest legislation has been important in reorganizing the forest sector, other causal factors including levels of technological and managerial expertise, credit availability and law enforcement structures play a decisive role in the successive implementation of forest legislation.  相似文献   

11.
ABSTRACT

This study examines a participatory forest management program and its impacts on forest conditions in Gebradima Forest, southwest Ethiopia. Vegetation data were collected from both participatory forest management (PFM) and nonparticipatory forest management (non-PFM) forest blocks. A total of 54 plots (27 from each forest block) measuring 20 m × 20 m were employed to collect species composition and structural data. Results indicated that a total of 51 different woody plant species (49 at PFM and 43 at non-PFM blocks), representing 31 families were recorded, with 41 species were shared for both forest sites. Species diversity and evenness were higher in the forest with PFM (H´ = 3.29, E = .85) compared to the forest without PFM (H´ = 2.97, E = .79). The overall mean values of tree/shrub and seedling density per hectare, diameter class (≤ 20 cm) were also significantly (p < .05) higher in PFM forest than non-PFM forests. However, no significant variations were observed in sapling density per hectare and basal area between the two studied forest blocks. It can be concluded that PFM had a positive effect on forest conditions compared with a similar forest without PFM. Hence, it is important to scaling up PFM in neighboring forests.  相似文献   

12.
Changes in physiognomy, species composition and structure, and dispersal mechanisms of canopy and subcanopy plant assemblages were investigated along a chronosequence of three ages: 12, 20, and 50+ years old (=old-growth), three replications in each, in an Atlantic Forest landscape in Northeastern Brazil. Our objective was to investigate whether there is floristic and structural convergence along secondary succession. There were significant differences between secondary and old-growth forests in density and basal area only for the subcanopy. Differences in density between forest ages were noted when the assemblage was analyzed per diameter and height classes. Richness of canopy species of both secondary ages differed from those of old-growth forests. Some dominant species in the canopy of secondary forests showed a significant decrease in density with increasing age, which indicates an ongoing process of floristic changes. The low level of shared species between secondary and old-growth forests supports the idea that species composition is one of the last components to recover during successional process. Zoochory was the most important dispersal guild in species percentage and number, irrespective of stand age. Although regenerating areas can take alternative pathways, our results indicate that secondary Atlantic Forest sites have a high potential for natural regeneration. This recovery is recorded as a physiognomic convergence of the canopy layer in as little as 12 years, and progressive introductions of later successional species into the plant assemblage that lead to convergence in terms of the diversity and richness of the subcanopy and of dispersal guilds just 20 years after abandonment.  相似文献   

13.
Community forestry in Nepal is one of the most cited examples of participatory management of natural resources. However, such programs have not yet been able to fully ensure equitable, gender-sensitive, and poverty-focused outcomes. This study examines factors influencing participation of households in forest protection, resource utilization, and collective resource management decision-making activities. The study was conducted among five selected forest user groups in the Kaski District. The analysis is based on a household survey that included a random sample of 176 respondents (69 males and 107 females). Three ordered logit regression models were developed to examine determinants of household participation in forest protection, resource utilization, and decision-making activities. Analysis showed that larger sized households belonging to forest user groups that owned less land were more likely to participate in forest protection activities. Women from larger households located closer to forests and markets were more likely to participate in forest resource utilization activities. Households with more livestock belonging to forest user groups that managed forests in good condition were also more inclined to participate in resource utilization activities. Women and individuals from lower castes demonstrated lower levels of participation in decision-making processes. Low participation was associated with education level and traditional customs, which may result in low representation of some social groups in forest user group committees.  相似文献   

14.
The relevance of forests to rural well-being and poverty reduction remains a controversial issue. This paper examines patterns of association between household wealth, poverty, and livelihood dependency either on forest extraction or agricultural activities in Ucayali, Peru. The analysis is based on survey data of 578 households with geographical, ethnic and environmental heterogeneity. A typology of economic strategies was defined through relative income shares derived from agriculture, forest, wages and other income sources. Our results show that households have multifaceted livelihood systems. While forest/environmental products provide nearly 40% of total income, agriculture is critical to both indigenous communities and to farmers of non-Amazonian origin. We test the hypothesis that households relying on agriculture are wealthier than forest-dependent households. In addition, we examine the role played by ethnicity and location as interacting variables. The analysis suggests a strong role of specific ethnic and locational configurations in shaping income and asset patterns, with some weak evidence of statistically lower poverty levels being credited to dependency on forest products. Context-specific assessments of livelihood–environment interactions provide critical insights to development and environmental policies and programs, which need to recognize different forms through which households integrate forest use and agriculture.  相似文献   

15.
伊春林区的林业已从传统林业向生态林业方向转变。资源型城市经济转型,发展非林替代产业,特别是林区广大林改户发展林下经济,都迫切需要符合实际的经营项目与技术支持。伊春林区野生榛资源丰富,进行野生榛林改培,成本低,收入可观,是林区职工增加经营林地收益的好方法。  相似文献   

16.
Norway has set ambitious targets for increasing bioenergy production. Forest residue extraction levels are currently very low, but residues have the potential to be an important component of the wood energy supply chain. A representative sample of Norwegian nonindustrial private forest owners having at least 8 ha (20 acres) of productive forest land was surveyed about their willingness to supply logging residues for wood energy production. About 59 % responded that they were willing to do so. Logistic regression analyses revealed that the following factors were positively associated with the likelihood of being willing to supply logging residues: total forest area, education level, living in a region with active timber markets and a history of forest production, and having positive perceptions of residue extraction and forestry’s role in mitigating climate change. Four variables were negatively associated with the likelihood to supply residues: living on property, being older than 65 years, having family or friends who are opposed to residue extraction, and having negative perceptions of residue extraction. The study provides insight regarding nonindustrial forest owners’ attitudes towards extraction of forest residues that may aid policy-makers designing effective means to meet national bioenergy production goals.  相似文献   

17.
We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub forests.We estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor method.We used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub forests.Over the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10~(12)g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 Tg.By stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub forests.Carbon storageincreased at an average annual rate of 0.8 Tg carbon over the study period.Carbon was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory periods.Broad-leaved forest was the main contributor to forest carbon sequestration.From 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 Tg.Our results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program.  相似文献   

18.
Many organizations in Ethiopia have for many years promoted exotic multipurpose fodder trees (EMPFT) for livestock feed and soil improvement. Despite the apparent benefits, the number of farmers planting these trees was low. The objectives were to elucidate farmers’ perceptions about their use value, management practices and constraints to adoption in three districts representing annual (one wheat-based and one teff-based) and perennial (coffee-based) crop-livestock systems in the Ethiopian highlands. Data were collected from 235 farm households. Most farmers (95.3%) had awareness of EMPFTs and the principal information sources were development agents (75.3%). Over half of the farmers were motivated to plant EMPFTs for feed value. Motivation for other purposes depended on cropping system, vegetation cover and availability of alternative local fodder trees in the area. Farmers had positive perceptions about EMPFTs for their feed value and contribution to soil conservation. Current adopters had a mean number of 587 (SE ± 84) EMPFTs per farm. Major constraints to adoption of EMPFTs were agronomic problems, low multipurpose value, and land shortage. Majority of farmers (89.8%) were interested to either continue or begin fodder tree development. Of the interested respondents, 44.5% preferred local fodder trees whereas 55.5% preferred EMPFTs. We conclude that farmers are aware of use values of EMPFTs while perceived constraints suggest that introduction of EMPFTs need consideration of farmers multiple criteria, but also awareness of feeding fodder trees and resource availability. Moreover, current development approaches have to recognize the importance of involving the end-users at all stages through participatory approaches to enhance adoption.  相似文献   

19.
Carbon sinks constitute an important element within the complex phenomenon of global climate change,and forest ecosystems are important global carbon sinks.The Natural Forest Protection Program(NFPP) is an ecological program in China that was established after catastrophic flooding in the country in 1998.The goals of the NFPP are to curb the deterioration of the ecological environment,strengthen the protection and restoration of habitat to increase biodiversity,and rehabilitate natural forests to support sustainable development in forest regions.This study looked at changes in carbon sequestration in a forested area of northeast China after the inception of the NFPP.The program divides China's natural forests into three classes—commercial and two types of noneconomic forests—that are subject to management regimes prescribing varying levels of timber harvest,afforestation,and reforestation.During the 18-year period from 1998 to 2015,the total amount of carbon sequestration increased at an average annual rate of 0.04 MT C.This trend reflects a transformation of forest management practices after implementation of the NFPP that resulted in prohibited and/or restricted logging and tighter regulation of allowable harvest levels for specific areas.In documenting this trend,guidelines for more effective implementation of forestry programs such as the NFPP in other countries in the future are also suggested.  相似文献   

20.
The aim of this study was to evaluate the influence of forest structure (mainly resulting from human uses) and forest type (the identity of the dominant tree species) on biodiversity. We determined the diversity of two taxonomical groups: the understory vegetation and the edaphic carabid beetle fauna. We selected eight types of forest ecosystems (five replicates or stands per forest type): pine (Pinus sylvestris) plantations of three age classes (10, 40 and 80 years since reforestation), an old-growth relict natural pine forest, and four types of oak (Quercus pyrenaica) stands: mature forests with livestock grazing and firewood extraction, mature forests where uses have been abandoned, “dehesa” ecosystems and shrubby oak ecosystems. The results obtained by a global PCA analysis indicated that both tree size and dominant species influenced the ordination of the 40 forest stands. In general, carabids were more sensitive to changes in forest heterogeneity and responded more clearly to the analysed structural variables than the understory vegetation, although the species richness of both groups was significantly correlated and higher in case of oak forests. Pine forest ecosystems were characterised by the lowest species richness for both taxonomical groups, the lowest plant diversity and by the lowest coefficients of variation and, consequently, low structural heterogeneity. As a result, it was very difficult to discriminate the effects of the spatial heterogeneity and the dominant tree species on biodiversity.  相似文献   

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