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Forest loss and fragmentation, which generate various negative environmental and ecological consequences, have become widespread phenomena across the globe. Motivation to investigate the underlying drivers is essential for land use planning and policy decision making. This paper characterizes forest loss and fragmentation from 1979 to 2014 in the Ningbo region (China) using multitemporal satellite imageries and a set of landscape metrics (area-weighted mean patch area, edge density, area-weighted shape index, Euclidean nearest neighbor distance, effective mesh size and total area); and then quantifies the responsible socioeconomic drivers (economy, social activities, science and technology, culture and policy, demography) under different land use planning schemes (urban and non-urban) using multivariate linear regression. Results show that the two zones present identical trend of intensifying forest loss and fragmentation but differ in changing magnitude and speed. More specifically, forest loss and fragmentation in the non-urban planning zone occurs at a significantly higher pace and magnitude. For the urban planning zone, population pressure, economic growth and fruit consumption are the primary drivers of forest loss, while forest fragmentation is mainly driven by economic openness, cash crop consumption and environmental protection consciousness. For the non-urban planning zone, income increases, fruit consumption and infrastructure development are the primary drivers of forest loss, while infrastructure and tourism development are the major drivers of forest fragmentation. Besides, forest loss and fragmentation in the two zones are both heavily subjected to land use policy. The variance partitioning analysis highlights that the policy driver is the most influential one and economic driver also has strong effect on forest loss and fragmentation in the urban planning zone. For the non-urban planning zone, the influence of policy driver is the strongest and social activity is also very powerful. These results provide compelling evidence that land use planning fails to play an efficient role in protecting forest resources in the Ningbo region. The failure should be attributed to several issues associated with land use planning and forestry governance that widely exist in China. We finally propose some pertinent implications and suggestions for China’s land use planning and forest policy. This study is believed to advance the understanding of the socioeconomic drivers of forest loss and fragmentation. It therefore provides some new insights in land use policy.  相似文献   

3.
Forest transition in South Korea: Reality, path and drivers   总被引:2,自引:0,他引:2  
While forest transition (FT) in South Korea began in 1955, when forest cover was only 35% of national land area, significant increases in both forest cover and growing stock really occurred in the early 1970s. Using reconstructed historical records, we empirically demonstrate that (1) FT in South Korea was mainly accomplished by the recovery of degraded, non-stocked forest; and (2) one-dimensional FT analysis using forest area alone has severe limitations in diagnosing meaningful changes in forest sustainability. The key driver of FT in South Korea was the government-led reforestation policy. The comprehensive reforestation plans, started in 1973, not only provided economic incentives to the general public by establishing clear quantifiable goals, they also promoted inter-agency cooperation and coordination, especially between the energy and forest sectors, to replace firewood with fossil fuels. These government-led efforts, accompanied by rural-urban migration, brought an increase in stocked forest area and a complementary rising average growing stock level. The case of South Korea shows that FTs can be cultivated in a relatively short period of time by a central authority, even with imperfect governance and low economic development.  相似文献   

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Forest transitions: An introduction   总被引:2,自引:0,他引:2  
When people speak about ‘forest transitions’, they generalize about the ways in which the extent of forested land changes as societies undergo industrialization and urbanization. Alexander Mather coined the term ‘forest transition’, outlined a theory to explain it, and carried out a series of careful historical studies to illustrate the idea. The papers assembled in this special issue both extend and deepen Mather's pathbreaking work. They suggest that the idea of the forest transition, like the much critiqued idea of a demographic transition in population studies, has become a useful theoretical tool for understanding contemporary land use changes.  相似文献   

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The concept of land use transition highlights that land use change is non-linear and is associated with other societal and biophysical system changes. A transition in land use is not a fixed pattern, nor is it deterministic. Land use transitions can be caused by negative socio-ecological feedbacks that arise from a depletion of key resources or from socio-economic change and innovation that take place rather independently from the ecological system. Here, we explore whether the sources of land use transitions are mostly endogenous socio-ecological forces or exogenous socio-economic factors. We first review a few generic pathways of forest transition as identified in national case studies, and evaluate the varying ecological quality of expanding forests associated with these pathways. We then discuss possible explanatory frameworks of land use transitions. We use the case of the recent forest transition in Vietnam as an illustration. Socio-ecological feedbacks seem to better explain a slowing down of deforestation and stabilization of forest cover, while exogenous socio-economic factors better account for reforestation. We conclude by discussing the prospects of accelerating land use transitions in tropical forest countries.  相似文献   

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In rural Ecuador and elsewhere in Latin America, the departure of migrants and the receipt of migrant remittances have led to declining rural populations and increasing cash incomes. It is commonly assumed that these processes will lead to agricultural abandonment and the regrowth of native vegetation, thus undermining traditional livelihoods and providing a boon for biodiversity conservation. However, an increasing number of household-level studies have found mixed and complex effects of out-migration and remittances on agriculture. We advance this literature by using household survey data and satellite imagery from three study areas in rural Ecuador to investigate the effects of migration and remittances on agricultural land use. Multivariate methods are used to disaggregate the effects of migration and remittances, to account for other influences on land use and to correct for the potential endogeneity of migration and remittances. Contrary to common assumptions but consistent with previous studies, we find that migrant departure has a positive effect on agricultural activities that is offset by migrant remittances. These results suggest that rural out-migration alone is not likely to lead to a forest transition in the study areas.  相似文献   

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By using Northeast China as example, this study measured the characteristics of the land use transition of underdeveloped areas (UAs) of China and explored the underlying transition mechanism. This study found that, the main characteristics of the land use transition of Northeast China during the last two decades (1995–2015) were continuous expansion of cropland, accelerated growth of construction land, and continuous reduction of woodland and grassland, as well as unused land. Policies dominate the process of land use transition of the UAs of China. The land use transition of UAs of China is a result of interaction and coupling between socio-ecological feedback under the guidance of policies and socio-economic change under the influence of policies. The former determines the direction of regional land use transition while the latter determines the intensity of this transition. During the process of land use transition, the sustainable use of land of the UAs of China faces several severe issues: inefficient use of urban construction land caused by unreasonable policy support, degradation of the ecological environment caused by irrational expansion of cropland, and both policy instability and policy conflicts. To resolve these issues, punishment and accountability of local governmental violations of land use should be strengthened. Furthermore, a land use information disclosure system and public supervision mechanism should be established by policy makers. The starting point of policy formulation should be shifted from quantity growth to quality improvement as well as from economic benefits to comprehensive benefits.  相似文献   

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Land consumption due to residential development, economic growth and transportation belongs to the most serious environmental pressures on landscapes worldwide, in particular in urbanised areas. Accordingly, the aim of containing the development of land is rated increasingly high on the agenda of environmental policy, at least in densely populated countries such as Germany, Belgium, the Netherlands or the UK. As a result, different strategies and instruments to prevent excessive land consumption are being discussed. However, many of these strategies and instruments adopt a rather general approach, while it seems more effective to define the particular areas where the goal of reducing land consumption is to be pursued. Such an approach must draw on information about how detrimental specific land use transitions are with regard to, for instance, the functionality of soils, water balance or habitat quality at specific locations. This paper introduces a conceptual framework for the impact assessment of land use transition in urban areas which highlights how such information can be acquired. This framework includes the differentiation of two levels of impact assessment: the level of the single land unit and the context level which takes into account regional and aggregated impacts of land use transition bound to the spatial context. The conceptual framework provides a basis to disaggregate (supra-)national policy targets regarding land use, to scale them down to the regional level, and thus to clarify the spatially explicit implications of land use policies.  相似文献   

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This themed issue of Land Use Policy builds mainly on papers presented at an international conference on ‘Land Use Issues and Policy in China under Rapid Rural and Urban Transformation’, convened by the Chinese Academy of Sciences in Beijing, China, in October 2012. The conference set out to share and promote new scientific findings from a range of disciplines that advance research on land use policy in China. The contributions to this themed issue provide conceptual–theoretical and empirical takes on the topic, around four main areas of interest to both researchers and policymakers: nation-wide land use issues, the Sloping Land Conversion Program, land engineering and land use, and land use transitions. Various land use issues have been associated with rapid urban–rural transformations in China, giving rise to formulation of new policies directly affecting land use. However, these have contributed to new land use problems due to the nature of the policies and the difficulties in policy implementation constrained by the special ‘dual-track’ structure of urban–rural development in China. In view of this, this themed edition makes a compelling call for more systematic research into the making and implementation of China's land use policy. It also emphasizes the challenges for further research on land use policy in China.  相似文献   

10.
By 2010, about 25% (180 million ha) of The International Tropical Timber Organization (ITTO) producer countries’ permanent forest estate was being managed using an approved forest management plan (FMP). While the existence of a FMP is often used as evidence of sustainable forest management (SFM), State officials mandated to monitor and verify FMPs’ implementation often lack the technical knowledge and political incentives to assess the changes that have been introduced, notably in terms of harvested volumes and species. Among tropical timber producers, Cameroon is considered to be exemplary for its progressive forest regulatory framework. Here we aim to estimate for the first time in sub-Saharan Africa the causal impact of the implementation of FMPs on harvested volumes, species and carbon stocks. We do so by using a 12-year (1998–2009) unbalanced longitudinal data set of a detailed, official harvesting inventory of 81 concessions in Cameroon. Results provide evidence to the theoretical expectations that for many years many practitioners have had on the implementation of SFM, i.e. that FMPs show a substantial opportunity to reduce carbon emissions from forest while presenting logging companies with acceptable financial trade-offs. We explore the technical and political reasons for our findings and conclude that these analyses are important for countries that are underwriting carbon-related schemes in which they propose to reduce their emissions through the effective implementation of SFM. We also demonstrate that producer countries do record useful information that, when effectively used, can help them to inform their policies and improve their sustainable development strategies.  相似文献   

11.
Consistent with the challenges of sustainability science, land architecture offers a comprehensive approach to land system dynamics useful for numerous types of assessments, ranging from the vulnerability of coupled human–environment systems to forest transitions. With antecedents in several research communities, land architecture addresses the tradeoffs within and between the human and environmental subsystems of land systems in terms of the kind, magnitude, and pattern of land uses and covers. This approach is especially cogent for changes in tropical forests, given the broad-ranging forces acting on them and the equally broad-ranging consequences of their loss. The rudiments of the land architecture approach are illustrated for changes in seasonal tropical forests in the southern Yucatán of Mexico, the pivot of which is the Calakmul biosphere reserve. Simplifying the dynamics involved, the region-wide land architecture is the collective design of stakeholders with different land-use goals that favor tradeoffs in subsystem outcomes serving better either the reserve and related programs or the smallholder farmers that populate the region. A major tradeoff involves forest cover per se, which holds implications for forest transition theory. Evidence for an incipient transition involves the scale of analysis taken. The dynamics involved hold too much uncertainty to forecast a permanent transition to more forest cover and imply that more complex but robust versions of the theory are required.  相似文献   

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Forests have historically been under significant land use pressures that cause periods of degradation, clearance, and recovery. To understand these changes, studies are needed that place trends in a historical landscape context and also examine recent dynamics. Here, we use historical investigation (c. 1800) and an examination of land use and land cover change between 1973 and 2006 to establish a baseline trajectory of the forested system of the south-central United States (US) plains. The study culminates in a highly detailed accounting of the processes and causes of land change between 2001 and 2006. In the study region, the forest transitioned from early low-intensity use, to clearance for farming and timber, to widespread recovery from degradation beginning in the 1930s. By 1970, the region was transitioning from recovered woodlands to an intensive regime of recurrent timber harvest and replanting. The recurring cycle inherent in intensive silviculture has been the main cause of land change for the past several decades, accounting for more than 95% of the total extent of change between 2001 and 2006. The transition to forest recovery in the south-central US was an important historical occurrence. However, the dynamic post-transition landscape needs to be better understood.  相似文献   

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Land Use and Land Cover (LULC) changes have profound impacts on the functioning of (agro)ecosystems and have potential to mitigate global climate change. However, we still lack interdisciplinary methods to project future LULC scenarios at spatial scales that are relevant for local decision making and future environmental assessments. Here we apply an interdisciplinary approach to develop spatially explicit projections of LULC at a resolution of 30 × 30 m informed by historic relationships between LULC and their key drivers, within the context of the four qualitative scenarios of global shared socioeconomic pathways. We apply this methodology to a case study in the Zona da Mata, Brazil, which has a history of major LULC changes. The analysis of LULC changes from 1986 to 2015 indicates that pasture area decreased from 76 to 58 % of total area, while forest areas increased from 18 to 24 %, and coffee from 3 to 11 %. Environmental protection legislation, rural credit for smallholder farmers, and demand for agricultural and raw products were identified as main drivers of LULC changes. Projected LULC for 2045 strongly depends on the global socioeconomic pathway scenarios, and forest and coffee areas may increase substantially under strong government measures in the environmentally conscious Green Road scenario or decrease in the high consumption Rocky Road scenario. Our study shows that under the set of drivers during the past three decades reforestation can go hand in hand with increase of agricultural production, but that major and contrasting changes in LULC can be expected depending on the socioeconomic pathway that will be followed in the future. To guide this process, LULC scenarios at the local scale can inform the planning of local and regional development and forest conservation.  相似文献   

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Research on the dynamics of tropical forest land use and cover change (LUCC) has focused on the three scenarios: (1) deforestation/degradation; (2) settled, degraded areas in recovery, and (3) sparsely settled, expansive, intact forest. Through examination of a central Quintana Roo, Mexico case study we propose a fourth scenario of a ‘sustainable landscape’: an inhabited, productively used, forested landscape that nonetheless shows little change or net gains in forest cover over the last 25 years. We use Landsat images to demonstrate a low incidence of net deforestation, 0.01% for the 1984–2000 period, the lowest recorded deforestation rate for southeastern Mexico. Institutional innovations such as an agrarian reform process that established large common property forests for non-timber forest product extraction, and later innovations such as sustainable forest management institutions have driven the outcome of low net deforestation, added to multiple organizational processes that promote sustainable land use.  相似文献   

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The Brazilian Atlantic Forest is widely recognized for its high levels of biodiversity and endemism. Its vast region concentrates also a large number of small farmers, who historically have been practicing swidden-fallow cultivation. Globally, there is contradictory evidence of the current fate of this traditional, integrated agricultural system, and the new land uses may have a strong impact on farmers’ livelihoods and ecosystem conservation. In this study, we assessed the land cover and land use change in a watershed where slash-and-burn cultivation was prevalent, aiming at understanding the drivers of change and discussing past and possible future impacts, including the perception of farmers on the drivers of land use change. We combined information gathered from interviews with 15 key informant farmers and from the analysis of remote sensing images for the years 1957, 1978 and 2011. Swidden-fallow cultivation has declined steadily since the 1950s. Part of the land was abandoned and forest succession was allowed to occur, increasing the total forest area; an apparently positive outcome. However, conversion to pastures and Eucalyptus plantations not only used much of the open land but also converted successional forests through deforestation, based on remote sensing. The willingness of farmers to grow more Eucalyptus and raise more cattle further increases concerns about the prospect for conservation. Our approach, combining remote sensing-based land change quantification and interviews, revealed to be complementary, allowing a better understanding of the past and possible future scenarios for the land use dynamics.  相似文献   

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The turnarounds from decrease to expansion in forest areas that took place during the last century have been examined through the lens of forest transition theory (FTT). Among temperate and Mediterranean European countries that have seen an expansion of forest cover, Portugal stands out as the only case in which this trend has recently been reverted. In this study, we explicitly map and document the forest transition (FT) in the country over the period 1907–2006, and investigate when and where forest transition happened de facto, and which were the land use transition pathways that resulted from the shrublands, agriculture, and forest interplay dynamics. After thematic and geometric harmonization of land cover maps from 1907, 1955, 1970, 1990, and 2006, a cluster analysis established four typologies, and a transition matrix was constructed to assess land cover dynamics. We found that up to 1955, FT occurred simultaneously with agricultural expansion, as shrubland areas diminished. Afterwards, with the retraction of agricultural area and the consequential decoupling of forest management from local actors, FT gained momentum and expanded up to the 1990s. While during the first half of the 20th century, forest expansion followed the “Scarcity” and “State Policy” pathways fostered by local socio-ecological feedback loops, throughout the second half of the century forest transition was driven by exogenous socio-economic forces, following “Economic Development” and “Globalization” pathways. We show how, despite these forces, FT can be derailed by endogenous factors such as wildfires, which limited and in some areas even reverted the afforestation process, initiating a deforestation phase. Since the necessary conditions for FT (technology shift, urbanization, agriculture retraction and public afforestation programs) were available in mainland Portugal, we advance the hypothesis that critical wildfire risk governance deficits may have been responsible for arresting FT. Considering the critical role of forests and other wooded areas in supporting climate change mitigation and sustainable development, our work provides useful evidence and insights for public decision makers on previously unaddressed dimensions of FTT.  相似文献   

17.
The devolution of forest management is high on the agenda in international forest policy. Devolution is generally conceived as a policy that aims to include a more diverse set of actors in forest management. One of the most problematic outcomes of devolution policies, therefore, is their tendency to exclude the claims of some local actors. This paper examines the exclusionary effects of devolutions in settings characterized by overlapping state and customary regulations and links these effects to exclusive notions of property and governance contained in particular devolution policies. The paper draws on insights gained in a pilot initiative of forest devolution in Vietnam's Central Highlands. Forest land allocation, as the initiative is called in Vietnam, took an exclusive approach to devolution by assigning ownership-type rights on forest to local actors, obliging those to protect the forest against encroachment by other actors, and centering governance in the state. In this particular case, exclusive devolution failed to diminish the gap between state and customary regulations, created conflicts among local actors, and contributed to forest loss. The unintended outcomes of exclusive devolution suggest the need for an inclusive approach to devolution that accommodates diverse kinds of overlapping claims made by multiple actors. The key elements of inclusive devolution are proprietary but not ownership rights granted to individual users and nested governance relations involving state and customary actors.  相似文献   

18.
People have planted trees in rural places with increasing frequency during the past two decades, but the circumstances in which they plant and the social forces inducing them to plant remain unclear. While forests that produce wood for industrial uses comprise an increasing number of the plantations, most of the growth has occurred in Asia where plantations that produce wood for local consumption remain important. Explanations for these trends take economic, political, and human ecological forms. Growth in urban and global markets for forest products, coupled with rural to urban migration, may spur the conversion of fields into tree farms. Government programs also stimulate tree planting. These programs occur frequently in nations with high population densities. Quantitative, cross-national analyses suggest that these forces combine in regionally distinctive ways to promote the expansion of forest plantations. In Africa and Asia plantations have expanded most rapidly in nations with densely populated rural districts, rural to urban migration, and government policies that promote tree planting. In the Americas and Oceania plantations have expanded rapidly in countries with relatively stable rural populations, low densities, and extensive tracts of land in pasture. If, as anticipated, the growing concern with global warming spurs further expansion in forest plantations in an effort to sequester carbon, questions about their social and ecological effects should become more pressing.  相似文献   

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Human societies constantly interact with the environment through mutual feedbacks and adaptations. The aim of this research was to analyze human and environmental dimensions so as to understand how the dynamic processes of land use and land cover change are contributing to the increase of forest cover observed between 1985 and 2011 in the Paraíba Valley, Brazil. The forestry sector, based on eucalyptus plantations, is given particular attention due to its role in these change processes. Multi-layer perception neural network (MPNN) models were adopted to evaluate the influence of independent variables in the process of the forest transition. Based on the model's results, we conclude that the process is conditioned by a set of biophysical and socioeconomic variables that operate during different historical periods and in different landscape settings. The proximity of Atlantic forest remnants was influential in the forest transition for the three periods analyzed: 1985–1995, 1995–2005, and 2005–2011. In the first period of change (1985–1995), topography was most influential. Between the periods of 1995–2005 and 2005–2011, the proximity to eucalyptus plantations was an important factor, indicating a high probability of native forest recovery occurring in the vicinity of these monocultural areas. The forest transition tends to occur in areas less suitable for agriculture at the outset, but as these areas are replaced by forest cover, socioeconomic drivers such as farm credit and economic development play important roles in forest recovery.  相似文献   

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