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1.
Patterns of land-use and land-cover change are usually grouped into one of two categories defined by the dominant trend: (1) deforestation resulting from expanding agriculture and (2) forest expansion, usually related to the abandonment of marginal lands. At regional scale, however, both processes can occur simultaneously even in the absence of net change. Given the focus on net change, such redistribution of agricultural and natural and seminatural lands has been generally overlooked. The interaction between agriculture modernization, human demography and complex topographic gradients of northwestern Argentina has resulted in processes of both forest recovery and deforestation, thus providing the opportunity to analyze patterns and driving forces of land-cover redistribution. We analyzed 20 years (1986–2006) of land-cover change in a subtropical watershed in relation to topographic and demographic variables. Although net forest change represented <1 %, forests redistribution affected 7 % of forest lands. There was a consistent geographic segregation of deforestation and forest recovery, with forests expanding over steep highlands and agriculture expanding over lowland irrigated areas. Population trends were not associated to forest expansion in lowlands but they explained 32 % of forest recovery in highlands. Highland forest expansion and lowland deforestation, respectively, imply conservation opportunities for humid montane forests and the environmental services they provide (e.g., watershed conservation) and threats for the conservation of dry forests and its biodiversity. Our study exemplifies the importance of land-use redistribution (rather than net change) with relevant environmental consequences at regional scale.  相似文献   

2.
The study presents three scenarios of land use and cover change (LUCC), the most important factor for environmental degradation in southern Mexico. We developed story lines and quantitative projections for regional scenarios based on historic LUCC processes, environmental policies, socioeconomic drivers, stakeholder consultations and official planning documents to gain a better understanding of drivers of LUCC, and quantitative scenarios were modeled with DINAMICA-EGO. Regionally specific interactions between social and natural systems are recognized, and detrimental policies and policy options for landscape conservation and management for sustainability are acknowledged in a base line, variant and alternative scenario. Incongruent policies and ineffective ground implementation of conservation actions were identified as the critical underlying drivers of deforestation and forest degradation that could lead to a severe reduction in natural forests, while the local socioeconomic situation stays precarious. The baseline scenario parts from an analysis of historic LUCC processes and shows the consequences of LUCC tendencies: 73% of temperate forests and 50% of tropical forests would get deforested until 2030. In the variant scenario, these tendencies are adjusted to planning goals extracted from official documents and recent changes in public policies. The alternative scenario further addresses policy options for fostering conservation and sustainable development, but because of the time lag of implementation, still 59% of temperate forests and 36% of tropical forest would get lost until 2030. Nevertheless, this represents a reduction of 13% of forest loss and 11% less pastureland due to the proposed measures of conservation, and sustainable management, including strategies for reforming agricultural systems, agricultural and forestry policies and trade, land tenure and livelihood risk management.  相似文献   

3.
The forest–grassland mosaics of southern Brazil have been subject to many land use and policy changes over the decades. Like many grasslands around the world, the Campos grasslands are declining with few conservation efforts underway. In contrast, forests receive much attention and many incentives. It is hypothesized that perception of land cover has the potential to shape ecosystems. Here we conduct a questionnaire to further our understanding of decision-making practices that alter landscapes (Campos grassland, Araucaria forest, agriculture and plantation) and direct land policies in the region. Our analysis reveals that plantations are significantly less desirable than the other landscape types. However, plantation land use has increased by 87 % over the past few decades, as a result of industry and government incentives. The proportions of other landscape types have remained consistent over the past two decades. Restoration of native vegetation is not a priority of landowners and restoration would require a financial incentive.  相似文献   

4.
With globalization, virtual exchanges of natural resources embodied in traded commodities redistribute geographically land use and its environmental impacts. Benefits of national forest protection may be undermined at the global-scale by leakage through international trade. We studied land use displacement associated with national policies to protect forests in Bhutan. This case study provides a simple situation: a dominant forest cover almost unaffected by agricultural expansion, a rural economy dominated by the primary sector, centralized forest conservation policies, and a dominant trading partner. We assessed the net effects at the international level of the Bhutanese forest protection policies by accounting for trade in wood products with India. Our results show that these policies have been effective in maintaining a high forest cover, but have been accompanied by an increasing displacement of forest use to India. In 1996–2011, the difference between the total volume of wood imported from India and the total volume exported from Bhutan—i.e., the net displacement—corresponds to 27 % of the total volume consumed in Bhutan. In 2011, 68 % of the total forest area required to produce the wood consumed in Bhutan was located in India. The wood imported by Bhutan was likely originating from tree plantations in the northeastern Indian states. Since Bhutan has few tree plantations and very valuable natural forests, the net international-level ecological impacts of this land use displacement is arguably positive. Most of the wood imports of Bhutan were wood charcoal for its emerging chemical industries. This case of displacement reflects functional upgrading in the value-chain rather than an externalization of consumption-based environmental costs. Through its government policies, Bhutan has managed to support its economic development while protecting its forests and leapfrogging the negative impacts on forests generally associated with the early stages of modernization.  相似文献   

5.
Habitat loss and degradation are main global threats to biodiversity, and land-use changes in agriculture-dominated landscapes are crucial for an important portion of biodiversity, especially in Europe. We evaluated the effects of land-use changes (1954–2012) on a threatened species, the ortolan bunting, in an agricultural area crucial for its conservation in Italy. We built a distribution model for ortolan bunting in current landscapes and then re-projected it to past scenarios (1954 and 1999–2000). We evaluated the most important land-use changes occurred and estimated their effects on habitat suitability. Bunting occurrence was mostly affected by the extent of grassland (positively; used as foraging/breeding ground), shrubland (quadratic effect; perches/shelter), forest and urbanized land (negatively), and by solar radiation (positively) and slope (quadratic), consistent with other studies carried out especially in southern Europe. The potential distribution of the species was much larger in the past: the estimated decline in suitable habitat is 44–72 % (since 1999–2000/1954), coherent with historical data suggesting strong decline and contraction. Changes in suitability (1954–2012) were mostly associated with changes in the cover of forest, vineyards and abandoned areas (negatively), and shrubland (positively). Land-use/land-cover changes are the main drivers of species occurrence and of habitat decline. The heterogeneous landscape of hilly/low-mountain sites in this area, characterized by a mix of habitats offering complementary resources to ortolan buntings and other species of conservation concern, is currently threatened by abandonment and intensification, but its maintenance may be promoted by a correct definition of Rural Development Programme measures.  相似文献   

6.
The integrated landscape approach is re-emerging in the global agenda as an approach which can give a fair deal to landscape functions such as climate change response, biodiversity conservation, food security, poverty reduction and economic growth. However, transformational change might be required to enable landscapes respond to these different functions. This is due to the sensitive nature of landscapes to local, national and global economic, social and political drivers. Based on national policy instruments, this paper presents a situational analysis of the landscape concept in Cameroon, operationalized as Technical Operation Units (TOUs) and in the context of the present institutional, social, economic and political features, it examines the rationale for a landscape approach in Cameroon. We notice potential trade-offs, indicating that the landscape approach is an opportunity for TOUs in Cameroon. Firstly, TOUs are characterized by multiple resource regimes with overlapping claims each having a legal land allocation and management plan. Secondly, TOUs are characterized by different stakeholders, with different land-use interests and motives, each controlling key components in the landscapes. Thirdly, the interests and motives of stakeholders overlap spatially and are connected to different sectoral policies at the national level. This setting might threaten decision making and the sustainability potentials of landscapes. Nonetheless, we propose areas for in-depth studies to generate knowledge and information to orientate win–win policy construction for landscapes. This is relevant for the social, ecological and economic objectives that underpin the sustainable development goals proposed in the post-2015 development agenda.  相似文献   

7.
Abstract

This paper examines the role and effectiveness of local institutions in the management of forest biodiversity in New Dabaga-Ulongambi Forest Reserve, Tanzania. Data were obtained through questionnaires, interviews, focus group discussions, participatory rural appraisal and field observations. The study revealed that the most remarkable local institutions connected to forest biodiversity management include: Village Natural Resources Management Committee (92%), tree nursery group (79.4%), beekeeping groups (61.1%), fish farming (43.3%), livestock rearing group (33.9%). Main activities carried out by local institutions which directly contribute to the sustainability of forest reserve include: forest patrols, fire extinguish, preparation of fire breaks, planting of trees along the forest boundaries, creation of awareness, arresting of forest defaulters, participation in income generation activities. For the purpose of realization that local communities are capable of managing forest biodiversity through their traditional institutions, the policy should provide tangible opportunity for local communities to meet their needs as they manage the forests.  相似文献   

8.
The types, frequency, and intensity of human interference with forests markedly affect the vegetation dynamics. Assessment of the impact of anthropogenic disturbances on forest diversity and structure is one of the central issues related to human behaviour and forest ecosystems and management. Both species diversity and density are very sensitive to local anthropogenic disturbance, which can be reduced depending on land-use systems. We used 10 line transects of 500 × 10 m to record and measure all plants ≥10 cm girth in some of the remaining forests surrounding villages in Tripura, Northeast India. To predict the effects of anthropogenic pressure on species richness and forest structure, we recorded and scored all ongoing disturbances in all transects of the forests. Although our study did not show any significant effects on the mean number of species, all diversity indices were significantly affected by disturbance. Total stem density (F = 128.60, p < 0.0001) and basal area (F = 65.30, p < 0.0001) of the forest stands were significantly affected by disturbance. Disturbance significantly (F = 84.81, p < 0.0001) impacts the abundance of mature voluminous trees removed by extensive illegal logging. Further, stem density at the middle (F = 10.01, p < 0.05) and upper (F = 131.70, p < 0.0001) canopy stories was also reduced by high disturbance intensity. The present analysis will be useful to policy-makers and planners for implementation of sustainable forest management at both the local and regional scale.  相似文献   

9.
Identifying the patterns of land cover change (LCC) and their main proximate causes and underlying driving forces in tropical rainforests is an urgent task for designing adequate management and conservation policies. The Lachuá region maintains the largest lowland rainforest remnant in Guatemala, but it has been highly deforested and fragmented during the last decades. This is the first paper to describe the patterns of LCC and the associated political and socioeconomic factors in the region over the last 50 years. We estimated spatial and temporal variations in LCC from a random sample of 24 1-km2 landscape plots during three time periods (1962–1987, 1987–2006, and 2006–2011) and evaluated how they were related to some important proximate causes and underlying driving forces. During the study period, 55 % of forest cover disappeared, at an annual rate of 1.6 %. The deforestation rate increased from 0.6 % (during the first study period) to 2.8 % (last period), but there was very high spatial variation. Landscape plots located outside conservation areas and close to roads lost between 80 and 100 % of forest cover, whereas the forest cover in landscapes located within protected areas remained intact during the study period. The establishment of new human settlements, roads, and annual crops was the main proximate cause during the first period, but during the second and third periods, open areas were mainly created to establish cattle pastures. Because ~75 % of forest cover has disappeared outside the protected areas, the conservation of this biodiversity hot spot will depend on the expansion of protected areas, and the promotion of forest regrowth and alternative biodiversity-friendly land uses in the landscape matrix.  相似文献   

10.
This paper examines the role and effectiveness of local institutions in the management of forest biodiversity in New Dabaga-Ulongambi Forest Reserve,Tanzania.Data were obtained through questionnaires,interviews,focus group discussions,participatory rural appraisal and field observations.The study revealed that the most remarkable local institutions connected to forest biodiversity management include:Village Natural Resources Management Committee(92%),tree nursery group(79.4%),beekeeping groups(61.1%),fish farming(43.3%),livestock rearing group(33.9%).Main activities carried out by local institutions which directly contribute to the sustainability of forest reserve include:forest patrols,fire extinguish,preparation of fire breaks,planting of trees along the forest boundaries,creation of awareness,arresting of forest defaulters,participation in income generation activities.For the purpose of realization that local communities are capable of managing forest biodiversity through their traditional institutions,the policy should provide tangible opportunity for local communities to meet their needs as they manage the forests.  相似文献   

11.
The vulnerability of forest ecosystem services to climate change is expected to depend on landscape characteristic and management history, but may also be influenced by the proximity to the southern range limit of constituent tree species. In the Western Rhodopes in South Bulgaria, Norway spruce is an important commercial species, but is approaching its current southern limit. Using climate sensitive forest models, we projected the impact of climate change on timber production, carbon storage, biodiversity and soil retention in two representative landscapes in the Western Rhodopes; a lower elevation landscape (1000–1450 m a.s.l) dominated by mixed species forests, and a higher elevation landscape (1550–2100 m a.s.l.) currently dominated by spruce. In both landscapes climate change is projected to induce a shift in forest composition, with drought-sensitive species, such as Norway spruce, being replaced by more drought-tolerant species such as Scots pine and black pine at lower elevations. In the higher elevation landscape a reduction in spruce growth is projected, particularly under the more severe climate change scenarios. Under most climate scenarios a reduction in growing stock is projected to occur, but under some scenarios a moderate increase in higher elevation stands (>1500 m a.s.l.) is expected. Climate change is projected to negatively influence carbon storage potential across landscapes with the magnitude depending on the severity of the climate change scenario. The impact of climate change on forest diversity and habitat availability is projected to differ considerably between the two landscapes, with diversity and habitat quality generally increasing at higher elevations, and being reduced at lower elevations. Our results suggest that if currently management practices are maintained the sensitivity of forests and forest ecosystem services in the Western Rhodopes to climate change will differ between low and higher elevation sites and will depend strongly on current forest composition.  相似文献   

12.
Vietnam, in the ongoing transition to market economies, has to cope with high rural poverty and a dramatic process of forest loss and environment degradation, particularly in the mountainous regions. The government considers rural poverty as the main cause of environment degradation, associated with slash-and-burn cultivation and to an unclear definition of property rights on forest land. In 1993, the government launched a Forest Land Allocation programme aiming to lease forest lands to individual households and, on this basis, to solve food security problems, halt the increasing environment degradation and preserve the remaining forests.To evaluate the results of this land reform policy, two upland pilot communes have been intensively monitored. The environmental and economic impacts of the forest land reform allocation in the two study areas are presented, after providing a background on the Vietnamese situation of mountain zones. On the basis of these findings, it is discussed as to whether the current forest land allocation process may actually promote local development and natural resources conservation, and under what conditions. Deforestation problems must be tackled also with new macroeconomic policies (e.g. credit programmes to support sustainable agriculture practices) and social policy (e.g. reduction of demographic pressure), together with the reform of the State institutions (e.g. State Forest Enterprises) involved in management of the forest areas.  相似文献   

13.
The island of Navarino, Chile, located at the extreme southern end of the Americas, is one of the few regions in the world with undivided and only slightly transformed temperate forests. Currently, fundamental issues are being addressed, such as how local fuel wood demands will be met without destroying primary forests and how a sustainable tourism industry may be developed. This study aims to inform these planning processes by providing data on the economic valuation of several non-market benefits provided by the temperate ecosystems of Navarino Island that have relevance to the local population. We focus this valuation on landscape esthetics, nature access restrictions, esthetic and ethno-symbolic benefits at the species level and the existence value of non-vascular endemic species. A choice experiment was applied to a sample of local residents (n = 230). Decisions about future development strategies were influenced by landscape esthetics being threatened by progressing levels of tourist infrastructure, nature access restrictions in favor of both economic and conservationist concerns, continued visits of an ethno-culturally important hummingbird, the protection of a moss endemic to the sub-Antarctic forests and species diversity. From a non-market valuation perspective, local residents favor a low-impact tourism development scenario. Little is known about the monetary value of Chile’s temperate forests. Knowledge of the economic value of Navarino’s temperate forests facilitates the understanding of local natural resource management at the microlevel and assists in formulating conservation policies at the regional and national levels.  相似文献   

14.
Negotiations of the Kyoto Protocol reached what has been called a moral position on biocarbon sinks which saw important limitations on their use in the Clean Development Mechanism (CDM), the Protocol’s main carbon offset system. After outlining this moral position, this article examines the consequences of these limitations on the viability of community forest participation in the CDM through a case study of three community forests in West Africa. Results suggest that there is significant carbon mitigation potential from forest conservation, reforestation as well as from improved fuelwood cookstoves at the community level. Yet under the current rules of the CDM, little of this overall carbon mitigation potential is able to be realized. Using qualitative research methodologies, it was learned that community respondents showed a pragmatic, yet cautious interest in the CDM while also emphasizing a need for land-use flexibility. The paper closes with a political discussion of the “‘moral position” on biocarbon sinks in the carbon market and concludes with policy recommendations for biocarbon sinks, in both the CDM and REDD, in the post-Kyoto climate change regime.  相似文献   

15.
The conservation and sustainable use of forests in the twenty-first century pose huge challenges for forest management and policy. Society demands that forests provide a wide range of ecosystem services, from timber products, raw materials and renewable energy to sociocultural amenities and habitats for nature conservation. Innovative management and policy approaches need to be developed to meet these often-conflicting demands in a context of environmental change of uncertain magnitude and scale. Genetic diversity is a key component of resilience and adaptability. Overall, forest tree populations are genetically very diverse, conferring them an enormous potential for genetic adaptation via the processes of gene flow and natural selection. Here, we review the main challenges facing our forests in the coming century and focus on how recent progress in genetics can contribute to the development of appropriate practical actions that forest managers and policy makers can adopt to promote forest resilience to climate change. Emerging knowledge will inform and clarify current controversies relating to the choice of appropriate genetic resources for planting, the effect of silvicultural systems and stand tending on adaptive potential and the best ways to harness genetic diversity in breeding and conservation programs. Gaps in our knowledge remain, and we identify where additional information is needed (e.g., the adaptive value of peripheral populations or the genetic determinism of key adaptive traits) and the types of studies that are required to provide this key understanding.  相似文献   

16.
The poverty of forestry policy: double standards on an uneven playing field   总被引:1,自引:0,他引:1  
Can policies designed to maximize exploitation by elites benefit the people who live in forests? Forestry policy throughout the developing world originates from European “scientific” forestry traditions exported during the colonial period. These policies were implemented by foreign and local elite whose interest was to maximize and extract profit. In spite of reforms since the end of the colonial period, policies on the environment usually remain biased against rural communities. Even when more recent policies are fair, the rural poor face severe biases in implementation. In addition, they must compete on an uneven playing field of ethnic and other social inequities and economic hurdles. This article examines how forestry policy and implementation maintain double standards on this uneven playing field in a manner that permanently excludes the rural poor from the natural wealth around them—producing poverty in the process. Change that would support poverty alleviation for forest-based communities requires a radical rethinking of forest policy so as to counterbalance widespread regressive policies and structural asymmetries.  相似文献   

17.
Mangrove forests in the tropics and subtropics grow in saline sediments in coastal and estuarine environments. Preservation of mangrove forests is important for many reasons, including the prevention of coastal erosion and seawater intrusion; the provision of spawning, nursery, and feeding grounds of diverse marine biota; and for direct use (such as firewood, charcoal, and construction material)—all of which benefit the sustainability of local communities. However, for many mangrove areas of the world, unsustainable resource utilization and the profit orientation of communities have often led to rapid and severe mangrove loss with serious consequences. The mangrove forests of the Takalar District, South Sulawesi, are studied here as a case area that has suffered from degradation and declining spatial extent during recent decades. On the basis of a post-classification comparison of change detection from satellite imagery and a survey of households, we provide an estimate of the mangrove change in the Takalar District during 1979–2011 and the consequences of those changes. Mangrove forest areas were reduced by 66.05 % (3344 hectares) during the 33-year period of analysis, and the biggest annual negative change in dense mangrove forest cover (8.37 %) occurred during the period 2006–2011. The changes were caused mainly by the mangrove clearing and conversion to aquaculture, and consequences have been increasing forest degradation, coastal abrasion, seawater intrusion, a decline in fish capture, a reduction in juvenile shrimp and milkfish, and outbreaks of shrimp disease. On the other hand, the clearing and impoundment of mangrove forests for shrimp and seaweed culture have provided a source of foreign exchange and new opportunities for employment in the study area.  相似文献   

18.
Fuelwood is one of the major sources of energy in the domestic sector across the rural areas, especially in the developing regions across the world. The Northeastern Himalayan state of Manipur is dominated by the tribal population that largely depends on fuelwood from the nearby forest area. The entire dependence on forests for energy resources is affecting the sustainability of the forest ecosystem in the region, thus indicating the livelihood conditions. Since land-use land-cover change is the key driver to the change in resource availability of a region, the present study has tried to analyze the land-cover changes over a period 28 years. The second major component affecting resource availability is the increasing population pressure that leads to changes in the land dynamics, which directly affect the resource production. Based on the existing consumption pattern, the total consumption of fuelwood in the watershed ranges from a minimum of 289.992 tons/year to a maximum of 3545.719 tons/year with an average of 1561.956 tons/year in the year 2009 and simulated fuelwood consumption for the year 2021 is around 1469.260 tons/year. Nine different probable scenarios of resource are proposed to calculate the stress value that can be used by the policy-makers and planners for suitable policy implementation at the micro level with a complex social system.  相似文献   

19.
Agricultural landscapes of the southern Brazilian Amazon are the result of 80 years of governmental policies to install a powerful agricultural sector. Yet, this rapid expansion raised important environmental considerations especially with regard to deforestation. The agricultural frontier is thus now facing a huge challenge: to combine socioeconomic development with environmental conservation in the context of frontier expansion. Based on a conceptual model of the agricultural frontier, we review historical changes in environmental and development policies in the Brazilian state of Mato Grosso and emphasize their ambivalent trend to both encourage and control the progress of the frontier. We then extend this model with an integration stage where environmental governance and economic development evolve from competing to complementary concepts. At this stage, the efforts to slow down deforestation are accompanied with programs to promote new agricultural practices and support industrialization. Finally, we put into perspective this recent evolution with regard to the underlying reasons for changing the agricultural model, thus considering the agricultural frontier to be at a tipping point where first positive results need to be confirmed in spite of an unstable economic and political situation.  相似文献   

20.
如何既注重生态环境的保护又满足区域经济、社会发展对土地利用的要求,成为当前我国不少地区土地利用中的一个重大课题。位于太湖流域和钱塘江流域源头的浙北天目山区,在土地利用与生态保护之间存在着多种矛盾。通过对浙北天目山地区生态保护与其他土地利用冲突及其协调的机理分析,试图寻找太湖流域上游山区生态保护与土地利用相协调的可选途径,探索自然保护区有效管护与当地经济发展、农民增收相结合的良性发展机制,并提出解决这些冲突的办法:修正保护目标,调整保护政策;建立合理的补偿机制;在不同的功能区施行不同的土地政策;把生态旅游作为解决土地利用冲突的突破口;探索社区共管模式,力争在扩大社区参与的前提下,实现保护区资源的可持续利用。  相似文献   

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