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1.
Natural forces and anthropogenic activities greatly alter land cover,deteriorate or alleviate forest frag-mentation and affect biodiversity.Thus land cover and forest fragmentation dynamics have become a focus of concern for natural resource management agencies and biodiversity con-servation communities.However,there are few land cover datasets and forest fragmentation information available for the Dhorpatan Hunting Reserve (DHR) of Nepal to develop targeted biodiversity conservation plans.In this study,these gaps were filled by characterizing land cover and forest frag-mentation trends in the DHR.Using five Landsat images between 1993 and 2018,a support vector machine algorithm was applied to classify six land cover classes:forest,grass-lands,barren lands,agricultural and built-up areas,water bodies,and snow and glaciers.Subsequently,two landscape process models and four landscape metrics were used to depict the forest fragmentation situations.Results showed that forest cover increased from 39.4% in 1993 to 39.8% in 2018.Conversely,grasslands decreased from 38.2% in 1993 to 36.9% in 2018.The forest shrinkage was responsible for forest loss during the period,suggesting that the loss of for-est cover reduced the connectivity between forest and non-forested areas.Expansion was the dominant component of the forest restoration process,implying that it avoided the occurrence of isolated forests.The maximum value of edge density and perimeter area fractal dimension metrics and the minimum value of aggregation index were observed in 2011,revealing that forests in this year were most fragmented.These specific observations from the current analysis can help local authorities and local communities,who are highly dependent on forest resources,to better develop local forest management and biodiversity conservation plans.  相似文献   

2.
通过对缅甸森林法律制度主要涵盖的森林物权、森林规划利用、森林开发许可、森林损耗补救和责任追究等方面规定的介绍, 认为缅甸森林法可谓得失利弊共存。其主要优点在于规划利用规定系统严密、特殊林木保护规定得力、森林损耗补救规定切实可行和刑事责任追究规定简明扼要, 主要缺憾则在于私人参与措施相当有限、国际合作协调规定大量缺失和责任追究规定远未完善。缅甸森林法对中国森林法的借鉴启示相当广泛。  相似文献   

3.
For any country, the forest policy is an important guideline to maintain forest resources and their interaction with other land uses. India devised its first National Forest Policy (NFP) back in 1894. There has been a paradigm shift from timber production to forest conservation followed by community-based agroforestry and social forestry bringing a change in perspective towards forest resources. This change has been socio-economic, cultural and ecological. Since the 1952 NFP, there has been an advocacy for 33% forest cover with a 60% forest cover in mountainous and hilly regions. This objective was reiterated in the NFP 1988 and also confirmed in the National Forestry Commission report in 2006. This paper reviews the probable reasons for these targets. This paper also analyzes forest cover trends at state level and assesses the likelihood of meeting the prescribed policy targets under present perspective of land use practices. Only three Indian states meet the prescribed policy, while three more have the potential to do so, if their state wasteland area is afforested. Among the rest, a few states may achieve the 33% goal provided land conversion to tree cover is not hindered, and adequate resources are available at state level. The Planning Commission (XI Five-year Plan, 2007–12) has emphasized inclusion of other natural ecosystems (including treeless areas and trees outside forests) to forest cover. The paper also examines the above prescribed targets in light of the Planning Commission recommendations. It is argued that that the NFP should be re-visited and revised to meet the targets, along with setting a more realistic and attainable target for Indian forest and tree cover.  相似文献   

4.
ABSTRACT

Researchers have long argued that improved livestock technologies and intensification will reduce the pressure on Latin America's forests. This article combines economic theory with insights from seven case studies to examine under what conditions technological change will reduce (or increase) forest clearing. In many contexts improved technologies—by making cattle production more profitable—will result in more forest being converted to pasture. Silvopastoral systems and other labor-intensive practices can restrain pasture expansion, at least in the short-run. Unfortunately, in most cases ranchers will only be willing to adopt such land-saving practices when land has become scarce and most of the forest is gone.  相似文献   

5.
This study analyzed the influence of government policy and tenure issues on farm and village forest use practices in Ekiti State, Nigeria. Three rural communities that were still far from urban influence were selected from each of the 16 local government areas of the state. In each community, 20 household heads were selected and interviewed with the aid of a semi-structured matrix. The interviews aimed at the determination of respondents' socioeconomic status, awareness and belief in the effectiveness or otherwise of the forest laws and regulations, land use, tenure and property rights. Results obtained revealed that the awareness of forest laws and regulations cut across the socio-economic categories. Most of these laws and regulations that were considered to be necessary could also constitute disincentives to sustainable forest development. Three types of land tenure niches—private holdings, commons, and government reserves—exist in the state. These led to land fragmentations in which individuals are now left with small holdings. Individuals with small and medium landholdings found it difficult to invest in tree planting; hence, they meet their subsistence use of wood and non-wood forest products from diverse sources. Individuals with large landholdings were found cultivating cash tree crops; timber species were not cultivated though their wildlings were preserved. Also, when land is let or leased out, tenants were not allowed to invest in tree planting on such land.  相似文献   

6.
The economy of the Ukraine is in transition from a communist command-and-control to a capitalist system. In this paper, we describe the current state of its forest resources, the structure of its forestry and wood processing sectors, and the problems facing policy makers. While the forest sector should be, and still has the potential to become, an engine for economic growth, the combination of past exploitation and the slow pace of economic reform are major obstacles to implementing rational forest policies. Given the right economic incentives and appropriate forest policies, it may still be possible for the Ukraine to improve its future timber supply while enjoying environmental benefits from its forests. However, this requires economic and institutional reforms beyond the forest sector.  相似文献   

7.
Remote sensing observations over areas of the former Soviet Union suggest that there may be important ongoing influences on forested landscapes resulting from divergent land use and forest management associated with the Soviet versus post-Soviet eras. As the Russian Federation implements its new Forest Code and associated regulations, knowledge of existing forest patterns and trends, plus the development of methods with which to understand the landscape-level influence of different forest management strategies is increasingly important. We developed spatial–temporal models and projections of forest patterns and trends over Soviet and early post-Soviet forest management eras for a study site in the Lake Baikal region in southern Siberia. We used Landsat-derived land-cover data, logistic regressions, and Markov and cellular automata methods (CA–Markov) to characterize patterns and trends 1975–1989 and 1990–2001, and to develop predictive scenarios through 2013. Relationships of forest types (Conifer, Mixed, Deciduous) and Agriculture to other explanatory environmental variables indicated mostly consistent forest–environment relationships, but some different spatial relationships between eras were found for Cut and Regeneration disturbance types. Landscape proportional trends showed greater differences between eras. Cut proportions observed via Landsat in 2001 were approximately 74% lower, and the area of Conifer observed was approximately 14% higher, than modeled proportions predicted for 2001 using 1975–1989 Soviet era transition rates. The proportion of Cut projected for 2013 was about 80% lower when based on early post-Soviet era probabilities. Overall, modeled results indicate that should early post-Soviet trends continue, low rates of logging, some agricultural abandonment, re-growing forests especially near access routes, increases in deciduous cover, along with continued or increased fire events in mixed and conifer forests will define the landscape. Should forest management change, for example to Soviet era rates and patterns of harvest, different outcomes are projected. More broadly, results highlight the real and prospective effects that divergent management strategies can have on forested landscapes, and demonstrate that land-cover data combined with emerging spatial–temporal modeling methods provide an approach to understand and project the complex and ongoing influences associated with changing forest management at landscape scales.  相似文献   

8.
We examined key drivers of deforestation in the Lake Victoria Crescent, Uganda from 1989 to 2009 through a case study approach with a multiple-case design. Nineteen focus groups with local community members and forest officials, archival analysis, and field observation revealed both proximate causes and underlying drivers of deforestation. Proximate causes of deforestation included agricultural expansion into forests, unsustainable extraction of wood forest products, and clearing of forests for nonagricultural uses. Underlying drivers of these proximate causes included policy and institutional factors, economic factors, population growth, technological changes, and changes in culture—each resulting in alienation of local people from forest resources. Alienation of local people, defined as a psychological dispossession of responsibility for forest resources, is posited as the most important underlying driver of deforestation. We discuss the importance of the involvement of local people in the management and maintenance of forests in the Lake Victoria Crescent.  相似文献   

9.
Forests expanded rapidly in northwestern Vietnam in the 1990s. Forest expansion coincided with a new forest policy that mandated the devolution of forest management authority. A cornerstone of the new policy was the allocation of use rights for forestry land and trees to rural households. This paper examines to what extent the new forest policy contributed to the observed forest expansion. The findings of three village studies suggest that the new forest policy had minor effects on actual property rights, as villagers resisted its implementation. Instead, forests expanded, mainly due to the liberalization of agricultural output markets and availability of new technology. Changes in markets and technology motivated farmers to intensify crop production, reducing agricultural pressure on land. The research findings suggest the potential of market-based instruments and technology policy to facilitate forest regeneration. They also demonstrate the benefits of in-depth village studies for forest policy analysis, as it provides an integrated framework for assessing the relative effects of political, economic and technological changes on forests.  相似文献   

10.
Some studies have attributed forest shrinkage to population growth, economic development, conversion of forest land to agricultural use and harvesting of trees for timber and fuelwood. But the statistical support for these hypotheses is not strong. This paper attempts to test the above hypotheses statistically in the case of Bangladesh. Factor analysis extracted 4 important factors—(a) exploitation of forests for timber, fuelwood, tea, and shrimp production, (b) demographic pressure in agriculture, (c) economic development, and (d) expansion of crop lands—as causes of deforestation. The statistical test supports the hypotheses that the exploitation of forests for timber, fuelwood, tea and shrimp production, and conversion of forests to crop lands have a negative influence on forest cover. Economic development and demographic pressure in agriculture are also negatively correlated with forest cover. Results of regression analysis show the conversion of forests to agricultural land is the most important cause of deforestation. Other important causes, in order of their relative importance, are the relative price of forest products, population growth, economic development, demographic pressure in agriculture, increasing production of shrimps, export of tea and shrimps, increasing production of timber and fuelwood, and expansion of tea lands. The statistical tests support the above relationships.  相似文献   

11.
Increased participation of local users in decision-making about forests and gaining benefits from these forests are major goals of the community forestry program in Nepal. However, there is a lack of real participation in community forest governance amongst users, particularly by poor and marginalised members. By employing a mixed-method approach, this research explores the issue of participation in the governance of community forests, and in particular the role of incentives in increasing participation. A partial least square approach is undertaken to link the participation indicators to the various incentives. Access to benefits, enforcement of legal property rights and social cohesion through building of local institutions are identified as the key influential incentives that determine the effective participation of users in community forest governance. Other incentive—including income supplements, community infrastructure development or payment for environment services—are insufficient to counter the opportunity cost of participation, and hence have a weak but still significant influence on users’ decisions to participate. Power inequality due to socio-cultural norms, together with poor economic capabilities and weak bargaining power, could undermine the meaningful participation of poor and disadvantaged groups in the governance of community forests, unless the community forestry institutions are strengthened in order to be able to deal with the issues of inequitable access and restricted opportunities at the local level.  相似文献   

12.
Climate change is a global concern. Within Nordic countries such as Finland it has particular influence on the use of natural resources. Family forest owners own 61% of the forested land in Finland and 80% of the industrial roundwood purchased comes from these forest owners. Thus how private forest owners approach climate change is of high national economic and ecological importance. In order to understand family forest owners' perspectives on climate change in their own forests, qualitative interviews along walks through the owner's forests were conducted. Analysis of the conversations during these walks highlighted that forest owners discussed the phenomenon without prompting more often than hypothesized. Additionally, forest owners were less certain as to the causes of changes observed in their forests, mostly willing to take advice from professionals, and economically-driven in their response. For those forest owners who did express concern regarding climate change, they were at a loss for ways their efforts could make a meaningful difference. The prevalent uncertainty among forest owners calls for guidance from authority. Policy practices should make an effort to combine monetary incentives along with climate change focused forest management practices. Additionally, forest owner's reliance on the advice and expertise of forestry professionals should be utilized when pursuing climate-motivated forest management.  相似文献   

13.
为充分利用楠竹林地空间,提高竹林经济效益,对楠竹林采用丰产技术措施培育笋用林,并在林下种植竹荪,实施菌笋复合经营。结果显示,通过对楠竹林采取调整立竹结构、劈山抚育、林地清理、林地垦复、留笋养竹、病虫害防治等一系列丰产技术措施,竹林春笋产量明显提高,较对照提高62.49%;若同时在林下种植竹荪,则春笋产量更高,较对照增加1.69倍,同时可收获鲜竹荪超过400 kg/667 m2。该研究总结出的一套楠竹林菌笋复合经营技术,具有重要的推广价值。  相似文献   

14.
On September 10, 1997, Indonesian President Soeharto renewed a ban on the practice of burning forests to clear land. At that moment a thick haze caused by land-clearing related fires in Kalimantan and Sumatra, Indonesia, blanketed large parts of Indonesia, Malaysia, Singapore, Brunei, the Philippines and Thailand. These fires, aggravated by the El Niño weather pattern and described as the worst in Southeast Asian history, renewed a long-term debate on slash-and-burn (S&B) as a method of land clearing.

Acceptable alternatives to S&B should address both the problems and the benefits of the use of fire. In depth knowledge and a clear diagnosis of the problems that rise with S&B and its alternatives are needed. A social/economic/agronomic survey was therefore conducted among 37 small-scale rubber producers in Sepunggur, Jambi Province, Sumatra, Indonesia. Our objectives were to: (1) characterize S&B techniques; (2) characterize farmers' perspectives on land clearing methods related to agronomic/economic factors (soil fertility, plant growth, production); and (3) evaluate alternatives to S&B that would be acceptable to individual farmers at present and in the near future. Small rubber producers (average farm size ≈5 ha) were selected because rubber gardens are the major land use type in this area, small producers are the main contributors, and most of the forest that is presently converted for agricultural use is being planted with rubber seedings.

Farmers generally start slashing in March and burn in the month of August. Burning takes place in two steps: broadcast burn followed by pile-and-burn. The five advantages of using fire as mentioned by the farmers were: (1) burning creates space (51%); (2) ash acts as a fertilizer (23%); (3) burning improves soil structure enabling faster establishment of seedlings (15%); (4) burning reduces weed/tree competition (5%); and (5) burning reduces the occurrence of pests/diseases (3%).

Alternatives to S&B should be economically acceptable. Mulching does not provide an alternative to any of the benefits of burning. Slash-and-remove-wood addresses only the first advantage and requires a tremendous effort in labor. If forced to accept either alternative, farmers expect a reduction in income due to difficulties in establishing new rubber gardens, reductions in yield, and an increase in labor costs.

At present, small quantities of wood with economic value are sold on the local market. Slash-sell-and-burn is an alternative that could maintain the advantages of using fire while supplying the farmer with extra income and the initiative to remove and not burn the trees. Even though forest is rapidly being converted to rubber gardens, land clearing will remain in practice to rejuvenate the old rubber gardens or to convert them to other land use systems. By selling rubberwood, farmers could cover costs of land clearing and earn enough to cover some of the costs of buying higher-yielding clones for rubber planting. This alternative has benefits similar to using fire and could significantly reduce pollution problems, but a change in local trade regulations and taxes is required for its successful adoption.  相似文献   


15.
Summary

With increasing opportunity costs of keeping land in forests because of increasing values for other land uses, such as for developed uses, forest ownership may become less attractive for some landowners and the return on investment less viable for both private and public landowners. This raises the question of what will become of the forests and the resources the forest supports, such as water and wildlife, if owners of the forests find it too costly to manage the forest. Land markets provide evidence on revealed behavior about what people are willing to actually pay for a bundle of rights necessary to gain access to land that can provide forest-based goods and services into perpetuity. However, owing to market failures and the nature of some forest land values, markets do not always reveal true forest land values, as discussed below. Allocation of land by use and cover types is a key determinant in sustainable forest management, with changes in land values providing important signals to land managers. Land valuation differs under market-oriented economies, emerging values in transition economies, and administered values in countries with command economies and is influenced by interactions between the environment and humans, including land ownership, use, and management.  相似文献   

16.
In this paper, we investigate the interactions and feedbacks between the drivers of forest cover and other land uses by building a novel longitudinal dataset and adopting alternative modeling strategies. Our longitudinal dataset integrates land-use and land-cover change (LULCC) information, derived by interpreting satellite imagery, with social-economic statistics across eight counties in Heilongjiang over a period of 37 years. Employing both instrument variable and system of equations methods, our models capture the inherent endogeneity embedded in the land-use changes and the effects of such factors as demographic change, economic development, and management transition on the forest condition. To validate the robustness of our models, a series of identification, endogeneity, and other tests are conducted. Our results demonstrate the dominant role of agricultural expansion in forestland loss as well as the importance of considering the substitution between forestland and wetland in analyzing the drivers of LULCC in general and deforestation in particular. The significant coefficient of the Natural Forest Protection Program implies that it has played a positive role in protecting local forests. The positive coefficient of built-up area in the farmland equation suggests a strong link between farming and residential/commercial construction; likewise, the negative coefficient of irrigation indicates that wetland loss is adversely affected by the change in local cropping pattern. It is hoped that these and other findings will improve our knowledge of the forest dynamics and their socioecological drivers, leading to more effective policy making and implementation and, ultimately, better resource conditions.  相似文献   

17.
This paper is based on a research project studying policy instruments for natural hazards protection in Austria. It discusses two theoretical approaches concerning instruments for political control: policy analysis and systems theory. Because of the stronger empirical basis, policy analysis was applied as the theoretical framework of the study. The findings are discussed for explaining the three essential instruments which are presented in this paper: the regulation of protective forests (ban forests) as a regulatory instrument, a subsidy programme for the restoration of mountain forests as an economic instrument, and the restoration plan for mountain forests as an informational instrument. According to liberal principles, the regulations allocate the costs for mountain forest management to the forest owners and to the beneficiaries of the protective effects of the forest. To avoid conflicts, however, these regulations are not implemented. The forest authority chooses subsidies for the restoration of mountain forests instead. Planning instruments are rather used for legitimizing the subsidies than for rational planning. The evaluation shows that policies can be explained in a better way by the institutional setting and the interests and values of political actors than by the formal characteristics of policy instruments. Three major conclusions are drawn for the analyses of policy instruments: (a) in practical application, the informal functions of policy instruments are more important than their formal characteristics; (b) policy instruments must not be analysed separately as they are not applied independently from each other; (c) in policy research a typology of policy instruments is useful as a model of reference but must not be mistaken for either an explanatory or a normative concept.  相似文献   

18.
The Beaver Hills region of central Alberta is located at the interface of the southern boreal mixedwood forest and the aspen parkland, an area now dominated by agriculture, urban and industrial development. Increasing anthropogenic land cover will eventually isolate remaining natural habitats currently protected in parks and reserves. This paper analyzes land cover and land cover change (LCC) in the Beaver Hills moraine and surrounding areas using a structured hierarchical satellite imagery classification applied to Landsat Multi Spectral Scanner and Thematic Mapper from 1977, 1987, and 1998. Our goal was to quantify deforestation and habitat fragmentation trends and then discuss how this information could be used to develop a conservation approach that will protect current areas against further habitat loss. We found that the rate of deforestation in the lands surrounding the moraine was similar to the broad trend at the southern periphery of the Canadian boreal forest region: annual rate of change in forest cover was −0.82%/year. However, in the Beaver Hills there was a net gain of +0.61%/year, due to regeneration of low quality agricultural lands. All fragmentation indices used indicated an increase in forest fragmentation. We designed a network of protected areas and remaining large forest patches, based on the UNESCO-MAB biosphere model. Our results underline concerns regarding the increasing isolation of national parks and biological reserves in Canada.  相似文献   

19.
Forest cover change is one of the defining contemporary environmental changes that validate the proposition of the Anthropocene narrative. Forest transition is a well-recognized global phenomenon, which has been studied and explained in well elaborated forest transition theory. Forest transition has been observed in over 30 countries, and it has been a trend in multiple countries in Asia. Forest transition is most relevant for the Anthropocene narrative, as it suggests that forest cover decline may eventually be followed by a forest cover increase at the global scale. The paper reviews evidence of forest transition in eight Asian countries and juxtaposes this with global forest cover trends. In Asia countries like China, India, Japan, Philippines, South Korea, and Japan and Vietnam are among the countries that have experienced an increase in the area under some kind of tree cover. Complex interplays of forest cover, population growth, economic development, demand for forest goods and services and governance effectiveness are the driving forces of forest transition. While it is not possible to extrapolate Asia's forest transition to the global scale, the Asian experience makes it possible to make statements on possible global forest cover scenarios. Ultimately, forest transition theory in general, and the experience of forest transition in Asia also support the concept and related narrative of the Anthropocene.  相似文献   

20.
By the end of the twentieth century, the forest cover over most of Europe had stabilized or was increasing after many decades of decline. Persistence and change in forest cover are driven by complex human–environmental interactions and feedback loops operating on different temporal and spatial scales. A promising method to detect these complex interactions between driving forces is a causal analysis based on historical documents. In the first step of this study, forest cover was reconstructed based on historical and contemporary maps of the Canton of Zurich at seven different points in time between 1664 and 2000. Secondly, causal chains of drivers were constructed based on historical document analysis, in order to investigate whether forest cover was stable or whether any compensating mechanisms in place were reducing the net changes. While the overall net forest cover remained considerably persistent in the Canton of Zurich throughout the 336-year study period, major gross forest cover losses and gains were detected during certain periods. Major deforestation events occurred during times of crisis, e.g., at times of economic or political crisis. In contrast, the strong persistence of net forest cover was mainly a consequence of the Forest Police Law, but can also be attributed to intensive land use. The law prohibits deforestation in general, and intensive land use is preventing the kind of natural reforestation occurring in other regions, e.g., the Swiss Alps. These empirical findings shed light on the relevance of a high degree of political and economic stability in terms of maintaining landscape persistence. These insights into the driving forces of forest cover change and persistence can contribute to protecting and managing valuable landscapes in a rapidly changing world.  相似文献   

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