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1.
《Southern Forests》2013,75(4):269-275
Land cover has changed rapidly across the tropics over the past century; however, detailed historical information describing the extent and possible drivers of such change is widely lacking. Here, we constructed a history of land-cover change at the district level in Malawi over a 37-year period from 1972 to 2009, the immediate post-colonial phase. Overall, there was a loss of 12 760?km2?(36%) of original forested area but also 11 161?km2?of new forest establishment, resulting in a relatively modest overall net loss of 1 599?km2?(5%). We correlated changes in deforestation and forest establishment with changes in socio-economic variables derived from spatially explicit data from the same time period. Deforestation was positively correlated with (in order of influence) changes in male school attendance, sex ratio, population density, hospital bed numbers, protected areas and dependency rate, but negatively correlated with changes in cattle density; forest establishment broadly showed the inverse relationships with the same variables. Although direct drivers of deforestation are well known for Malawi and much of Africa, the significance of socio-economic variables within this study can help to understand the underlying social pressures behind such drivers. In particular, development, population pressure and demographic factors are important predictors of deforestation rate within our study area.  相似文献   

2.
As REDD+ countries are moving towards the implementation phase of their national REDD+ programs, it becomes crucial to better understand what drives deforestation in order to identify policy responses. This however, remains challenging because, while the number of scientific assessments of deforestation drivers is increasing, they often reach diverging conclusions. Deforestation drivers can have long underlying causal chains and take different shapes depending on the perspective that is chosen. As states are the official owners of forests in most African countries, analyzing the perspective of policy makers on deforestation in this context, helps revealing deforestation drivers that are harder to quantify, define and measure with usual proxies. It also potentially allows identifying politically and institutionally feasible deforestation reduction measures.In this paper content analysis is used to assess how African policy makers perceive deforestation drivers. We find that they strongly emphasize the role of institutional and policy drivers. Furthermore, we find that some of the complex issues related to forest governance in general, can be narrowed down to very specific problems. In light of these findings, we will argue that mechanisms and standards have to be found to allow institutional and policy drivers of deforestation to be addressed in the result-based payments phase of REDD+.  相似文献   

3.
The dynamics of the Atlantic Rainforest loss and recovery are still not fully understood despite its long history of human occupation. In this study, we investigated changes in an Atlantic Rainforest region due to major biophysical and human proximate causes. First, we modeled land-cover and land-use changes from 1962 to 2000, including deforestation and forest regrowth, and thereby simulated future landscape trajectories to assess their possible effects on the conservation of forest species of the Ibiúna Plateau, a region located in Southeastern Brazil within the Atlantic Rainforest biome. We modeled four scenarios (status quo, random, lawenforcement, and land-use intensification) and simulated their resulting landscape trajectories for the year 2019 using DINAMICA. The landscape dynamics in the study region were particularly intense. During the first period of 1962–1981, the rate of forest regrowth (3% year−1) was greater than the rate of deforestation (2% year−1), whereas in the latter period of 1981–2000, increasing urbanization and the spreading of rural establishments resulted in more deforestation (2.9% year−1) than regrowth (1% year−1). These dynamics imprinted a heterogeneous landscape, leading to the predominance of progressively younger secondary forests with increasingly less capacity of hosting sensitive forest species. The influence of proximate causes on the dynamics of deforestation and forest regrowth showed consistent patterns, such as higher forest regrowth rates near rivers, on steep slopes and far from dirt roads, whereas losses in young secondary vegetation and forest were far from rivers, on gentle slopes and near urban areas. Of the modeled scenarios, only the law enforcement scenario may lead to the recovery of a network of interconnected forest patches, suggesting that simply the enforcement of current forest laws, which prohibit deforestation on unsuitable agricultural areas and along river margins and establish a minimum of 20% of forest remnant per rural property, may effectively favor forest species conservation in the short term (two decades) without the need of any forest restoration effort.  相似文献   

4.
森林的经营和管理主要是为了使森林资源能够得到永续利用,森林资源的分布受到许多因素的影响,而森林采伐率是影响森林资源重要指标之一。森林采伐率的大小能够直接影响森林的发展以及经济效益,所以如何能够有效的控制好森林采伐就成了至关重要的问题。从森林采伐率出发,运用非线性规划的方法,得出有关最优采伐强度的优化模型,对于不同树种,只需将相应的数据代入,就可以运用计算机模拟等有效的方法,得出来相应的最优采伐强度值,为森林资源的可持续经营和利用提供可计算的最优采伐强度的方法。  相似文献   

5.
Tropical deforestation in the Asia-Pacific Region has accelerated in Lhe last decade, seriously depleting the forest resource base. Most forest loss results from agricultural clearing, but is generally preceded by forest degradation from destructive logging (Southeast Asia) or overuse of forest resources (South Asia). Tropical forests are highly variable, requiring a system of classification to guide management objectives; one such system is ecological life zone mapping. Forestry operations should reflect the need for both conservation and production. Most Asia-Pacific forests are managed on variations of a selection system. Logging damage is the most important forestry-sector threat to commercial forestry, reducing both future timber production and the availability of non-timber products. The short duration of logging concession agreements, nontransferability of concession contracts, and undervaluation of forest resources all contribute to forest "mining" practices. Alternative forest management methods exist: logging damage can be substantially reduced at little or no additional cost; small-scale mobile sawmills can increase local incomes while reducing the need for skidding; and Assisted Natural Regeneration can facilitate the reforestation of denuded lands. The best hope for sustainable use of forest resources lies with those who must live with the consequences of forest mismanagement. Local involvement in foresy planning, implementation and enforcement is essential. Successful forest management projects depend on the judgement of field-based personnel familiar with the forests, cultures and institutions of each country, working in cooperation with local forestry experts and forest-dependent people.  相似文献   

6.
Policies play a vital role in setting priorities and actions for forest use and management. High rates of forest loss can be attributed to failure by policies to reduce deforestation and forest degradation. It is argued that in most Least Developed Countries such as Zambia, adopted forest and natural resources policies are rarely put into effect resulting in ecosystem degradation.This study examined policy actor's perception of implementation of policies aimed at reducing deforestation and forest degradation and their implications for forest resources.To examine policy implementation, 55 policy actors were interviewed at national, regional and local levels. This included government officials, Non-Governmental Organisations, traditional leaders and local people. Interviews were analysed using discourse analysis.Findings show that policy implementations deficits are prevalent in Zambia's forest sector. Policy actors identified the main barriers as inadequate institutional capacity, inadequate legal framework, political influences, insecure land tenure, poor funding, and lack of intersectoral coordination. The paper has shown gaps between policies and their implementation. To halt deforestation and forest degradation, it is imperative that formulated policies are implemented. This will require improved communication and coordination among government units and various stakeholders, sufficient resources and harmonizing policies and legal frameworks.  相似文献   

7.
We examined the local community incentive programs to improve traditional forest management in three forested villages in Baneh city, Kurdistan province in the northern Zagros forests of western Iran. Zagros forests cover 6.07 million ha and support rich plant and animal diversity. Changes in local community social and economic sys-tems and the inefficiency of traditional forest management led to a criti-cal situation in the stability of forest regeneration in recent decades. Due to a shortage of productive and arable lands and resulting unemployment and poverty, people overexploited the Zagros forests. Outside interven-tion in traditional forest management creates conflicts between local peoples and forest management organizations. To achieve sustainable forest management, including forest resources conservation and im-provement of natural resource based livelihoods of communities, it is desirable to implement Forestry Incentive Programs (FIP) based on the important functions of forests. Detailed information on the so-cio-economics of communities, the effect of forests on local livelihoods, and lists of products extracted from the forest were obtained from a sur-vey of local communities though questionnaire, interview and observa-tion. We studied 276 households in three villages and completed 76 ques-tionnaires by householders in the quantitative analysis. Sampling was performed by simple random sampling (SRS). The needs of rural com-munities, such as livestock husbandry, mainly arise from the characteris-tics and environmental features of villages. We identified the driving forces, pressures, status, impacts and responses (DPSIR) to design incen-tive programs, by DPSIR analysis and interaction analysis. Evaluation of local community benefits from forests showed that in order to improve forest management, 319 dollars per year would be needed by each family as an incentive in 2010 to prevent lopping and firewood collecting, the main causes of forest degradation.  相似文献   

8.
Cumulative losses from shifting cultivation in the tropics can affect the local to regional to global balance of carbon and nutrient cycles. We determined whether shifting cultivation in the Southern Yucatán causes feedbacks that limit future forest productivity and carbon sequestration potential. Specifically, we tested how the recovery of carbon stocks changes with each additional cultivation-fallow cycle. Live aboveground biomass, coarse woody debris, fine woody debris, forest floor litter and soil were sampled in 53 sites (39 secondary forests 2–25 years old, with one to four cultivation-fallow cycles, and 14 mature forests) along a precipitation gradient in Campeche and Quintana Roo, Mexico. From the first to the third or fourth cultivation-fallow cycle, mean carbon stocks in live aboveground biomass debris declined 64%. From the first to the third cycle, coarse woody debris declined by 85%. Despite declining inputs to soil with each cultivation-fallow cycle, soil carbon stocks did not further decline after the initial conversion from mature to secondary forest. The combined aboveground and soil carbon stock declined almost 36% after conversion from mature forest, however two additional cultivation cycles did not promote further significant decline, largely because of the stability of the soil carbon pool. Although age was the dominant factor in predicting total carbon stocks of secondary forests under shifting cultivation, the number of cultivation-fallow cycles should not be neglected. Understanding change beyond the first cycle of deforestation will enhance forest management at a local scale by improving predictions of secondary forest productivity and related agricultural productivity. A multi-cycle approach to deforestation is critical for regional and national evaluation of forest-based carbon sequestration. Finally, models of the global carbon cycle can be better constrained with more accurate quantification of carbon fluxes from land-use change.  相似文献   

9.
In Rondônia State, Brazil, settlement processes have cleared 68,000 km2 of tropical forests since the 1970s. The intensity of deforestation has differed by region depending on driving factors like roads and economic activities. Different histories of land-use activities and rates of change have resulted in mosaics of forest patches embedded in an agricultural matrix. Yet, most assessments of deforestation and its effects on vegetation, soil and water typically focus on landscape patterns of current conditions, yet historical deforestation dynamics can influence current conditions strongly. Here, we develop and describe the use of four land-use dynamic indicators to capture historical land-use changes of catchments and to measure the rate of deforestation (annual deforestation rate), forest regeneration level (secondary forest mean proportion), time since disturbance (mean time since deforestation) and deforestation profile (deforestation profile curvature). We used the proposed indices to analyze a watershed located in central Rondônia. Landsat TM and ETM+ images were used to produce historical land-use maps of the last 18 years, each even year from 1984 to 2002 for 20 catchments. We found that the land-use dynamics indicators are able to distinguish catchments with different land-use change profiles. Four categories of historical land-use were identified: old and dominant pasture cover on small properties, recent deforestation and dominance of secondary growth, old extensive pastures and large forest remnants and, recent deforestation, pasture and large forest remnants. Knowing historical deforestation processes is important to develop appropriate conservation strategies and define priorities and actions for conserving forests currently under deforestation.  相似文献   

10.
Protected areas (PAs) are a country's key strategy to conserve and manage forest resources. In sub-Saharan Africa, the effectiveness and efficiency of PA institutions in delivering sustainable outcomes is debated, however, and deforestation has not been avoided within such formal regimes. This paper analyzes the processes that led to deforestation within the PAs on the transboundary Mt. Elgon, Uganda–Kenya, employing institutional theory. Landsat satellite imagery helped identify and quantify forest loss over time. The study showed how, since 1973, about a third of all forests within the PAs on Elgon have been cleared in successive processes. Within formal protected area regimes, complex political and institutional factors drive forest loss. We argue, therefore, that policies to counter deforestation using a PA model have to be considered and understood against the broader background of these factors, originating both inside and outside the PA regimes.  相似文献   

11.
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   

12.
Sal (Shorea robusta Gaertn. f.) forests cover over 11 millionha in India, Nepal and Bangladesh, and these forests are conventionallymanaged for timber. Recently, interest in producing multipleproducts from sal forests has increased; accordingly, a silviculturalregime for managing sal forest for multiple products is a centralconcern. Forest managers need a comprehensive scientific understandingof natural stand development processes and anthropogenic factorsaffecting sal forest when designing silvicultural regimes formultiple-product management. We review ecology and productivityplus anthropogenic niches of sal forests. Information on edaphicfactors, phenology and stand development processes (regeneration,growth characteristics, soil nutrient requirement, growth allocation,nutrient cycling, stand structure and successional stages) isimportant for designing scientific forest management of salforest; likewise, knowledge of anthropogenic factors associatedwith use of sal forest is also required for effective implementationof the recently paradigmed management efforts. Sal forest silviculturehas been evolving since the beginning of the twentieth centurymainly concentrating on timber production, though the sal forestshave always been used also for grazing and collection of fodder,fuelwood, litter and many other products. Instead of integratingthese products in sal forest management, governments have attemptedto control these additional uses through enforcing forest legislation.These attempts resulted in the persistent conflicts betweenthe interests of local people and the government, and the deterioratingcondition of sal forests. Community-based forestry in this regionemerged in response to the severe degradation of forest resources,and local people initiated protection practices and demonstratedthe success of sal forest from coppice. The coppice systemsallow managing forests with intermittent products (non-timberforest products, including fodder and litter) while producingtimber in the long term. Accordingly, a policy has been developedto manage coppice sal forest for multiple products. Managingthe sal forest for multiple products is, however, a relativelyrecent development and scientific investigations on variousaspects of multiple-product forest management need to be initiated.Ecological processes indicate good prospects of managing salforest for multiple products. The review indicates that theecological processes and anthropogenic factors form sound basisfor developing multiple-product management.  相似文献   

13.
Abstract

It is claimed that reduced emissions from deforestation and forest degradation (REDD) could contribute to sustainable management of forests and enhancement of forest carbon stocks as well as having the potential to deliver significant social and environmental co-benefits (+). From the perspectives of local factors and broader governance issues related to REDD+, this study aims to explore findings related to three crucial elements, commitment, transparency and continuity, implemented jointly with participatory forest management in Tanzania in the case of the REDD+ mechanism. This paper argues that commitment and transparent systems are needed at village level, as well as at the various levels of forest governance and among the donors, in order for REDD+ benefits to be shared equitably at the REDD+ project level. Any REDD+ project should include safeguards that recognise and protect the continuity of multipurpose functions of the forest to local people and avoid dependence on external payments.  相似文献   

14.
Within various parts of the tropics and temperate regions, there are increasingly more efforts towards reforestation or restoration. Interventions in the tropics however, have not adequately addressed the needs of local people compelling them to degrade forests. We conducted a study in and around Mabira Forest Reserve in Uganda with the aim of assessing locally proposed restoration techniques and conditions for empowering local people to raise their willingness to participate in forest restoration practices. We specifically set out to; (i) identify proposed techniques to restore the degraded forests, and (ii) determine the pre-conditions for supporting local people’s participation in restoration activities. Data were collected using individual semi-structured interviews, focus group discussions and participatory forest surveys. The findings show that the local people mainly engaged in practices that address their needs concurrently. The most reported practices include: planting trees on farm, enrichment tree planting in the forest, control of soil erosion, and control of invasive alien species. The main pre-conditions for their participation in forest restoration is assurance for more access to forest resources. The efficiency of local people in restoration will be enhanced by strengthening their capacity for collaborative forest management, raising their awareness on restoration, building their capacity, as well as continuous monitoring by forest managers.  相似文献   

15.
广西大瑶山森林生态系统服务功能包括 :提供丰富的林产品 ;产生并维持生物多样性 ;涵养水源 ;调节气候 ;土壤肥力的保持与增长 ;生态旅游等。由于该山区经济落后 ,毁林开荒 ,乱砍滥伐 ,烧柴烧炭等现象时有发生 ,导致森林遭到破坏 ,生态环境不断恶化。为此提出了可持续发展的保护措施。  相似文献   

16.
Social forestry as a development strategy has evolved since the 1970s, especially in the tropics, to address forest degradation and promote local community development amidst the burgeoning population in these areas. As a practice, however, social forestry has been in place since ancient times in many parts of the world, including Japanese forest communities. Forest-people relationships in Japan drastically changed through massive afforestation programs after the energy source change and with the industrialization of the forest sector in 1950s. The majority of the planted forests are underutilized today and forest communities are marginalized due to the decline of forestry operations, depopulation, and changes in people’s values. Some communities address this concern by inviting potential urban migrants who may be interested in settling in rural areas. Using the case of the Nishiawakura Village in Okayama Prefecture, this paper explores the recent challenges confronting social forestry in Japan. It is found that underutilization of forest resources can be a cause of serious environmental degradation and marginalization of forest communities, and that Nishiawakura’s journey to renew forest management in partnership with migrants is a process of revisiting and creating the forest-people relationship. This study advances two related arguments, namely (1) the interaction of the local people and the migrants brings new perspectives to forest management, and (2) in a community facing depopulation and underutilization of forest resources, social forestry can be an effective approach to rediscover traditional forest management in a new form and revitalize forests and local communities.  相似文献   

17.
Land use and landscape changes, which have much effect on local biodiversity, are driven primarily by socioeconomic forces. Understanding these forces is important for preservation of current biodiversity. In this study, we clarified the socioeconomic forces that have brought about changes in the forest landscape around the Ogawa Forest Reserve in the southern Abukuma Mountains, Japan, by interviewing local residents and reviewing local historical documents. Furthermore, we reconstructed past forest landscapes and quantified the changes that have occurred from the beginning of the twentieth century until the present by use of old land-use maps and past aerial photographs. The use of forest resources has dramatically changed during the past hundred years, and it can be divided into three periods corresponding to the level of economic development. The main landscape has changed significantly from one mainly composed of expansive grasslands and broad-leaved forests into a mosaic of fragmented secondary forests and coniferous plantations. These landscape changes reflect shifts in both the use of forest resources by local residents and the management of the national forests. Clarifying temporal–spatial landscape changes by understanding the historical relationship between humans and the landscape provides useful information for optimizing conservation and management planning.  相似文献   

18.
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   

19.
Indonesia experienced massive deforestation in the last decades where rapid oil palm expansion has been considered as one of the main drivers. This article shows that the process of deforestation and the rapid oil palm expansion cannot be viewed in isolation from broader development contexts. Various actors at local, national, and global levels have used development narratives and poverty alleviation through various policies and institutional setting to create spaces and opportunities for oil palm development. These actors also deliberately created the notion of forest crisis by omitting the values of forest environmental services to justify forest conversion into oil palm plantations. These multiple factors shaped the speed and the direction of oil palm expansion in Indonesia. This rapid oil palm expansion in Indonesia has resulted in massive LUCC and serious environmental problems. Given these complexities, a single policy will not be sufficient when it comes to managing the consequences of rapid oil palm expansion in Indonesia.  相似文献   

20.
森林资源的消长与社会经济发展密切相关,而林业的兴衰又直接关系到国民经济和社会的发展。当前,世界林业面临的"四大危机"大部分又是与热带林的破坏密切相关的。因此,研究热带林发展战略是研究当前世界林业的核心问题。本文根据国际组织和各国的大量文献,着重就世界热带林的现状、毁林速度、毁林模式、原因和后果等问题进行了论述。  相似文献   

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