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1.
Land use and climate change are both strong drivers of landscape transformation. Using a representative valley of the Central Alps (Stubai Valley, Tyrol, Austria) we assess (1) the historical and likely future spatial patterns of land use/land cover (LULC), (2) the influence of temperature increase on the LULC distribution, and (3) the speed at which these changes will occur. Based on the historical landscape development and spatially explicit models, the effects of various land use and climate scenarios were modelled. Employing a pan-Alpine model, we were able to detect the temporal trajectory of spatial reforestation. The results show that land-use changes that already occurred during the last decades are responsible for the main future LULC changes (by secondary succession). Only an extreme land abandonment scenario and extreme climate scenarios (5 K temperature increase) would bring about similar changes in LULC distribution and expansion of the forested areas. While alpine grasslands, alpine pioneer formation and glaciers would shrink drastically, especially deciduous forests would spread. To a considerable degree, such changes might take place over the next 300 years. By contrast, the increase in forest areas triggered by temperature changes would be slower and longer termed (up to 700–800 years).The effects and intensity of land-use change in the investigated valley, that is comparable to many regions in the Alps, will be at least equally severe and responsible for transformation of the landscape as those of a projected temperature increase.  相似文献   

2.
Recent studies assessing plausible futures for agricultural markets and global food security have had contradictory outcomes. To advance our understanding of the sources of the differences, 10 global economic models that produce long‐term scenarios were asked to compare a reference scenario with alternate socioeconomic, climate change, and bioenergy scenarios using a common set of key drivers. Several key conclusions emerge from this exercise: First, for a comparison of scenario results to be meaningful, a careful analysis of the interpretation of the relevant model variables is essential. For instance, the use of “real world commodity prices” differs widely across models, and comparing the prices without accounting for their different meanings can lead to misleading results. Second, results suggest that, once some key assumptions are harmonized, the variability in general trends across models declines but remains important. For example, given the common assumptions of the reference scenario, models show average annual rates of changes of real global producer prices for agricultural products on average ranging between ?0.4% and +0.7% between the 2005 base year and 2050. This compares to an average decline of real agricultural prices of 4% p.a. between the 1960s and the 2000s. Several other common trends are shown, for example, relating to key global growth areas for agricultural production and consumption. Third, differences in basic model parameters such as income and price elasticities, sometimes hidden in the way market behavior is modeled, result in significant differences in the details. Fourth, the analysis shows that agro‐economic modelers aiming to inform the agricultural and development policy debate require better data and analysis on both economic behavior and biophysical drivers. More interdisciplinary modeling efforts are required to cross‐fertilize analyses at different scales.  相似文献   

3.
Forest ecosystems deliver valuable services to humanity. However, many forests are being degraded and their services have been undervalued. The main problem lies in the inadequate institutional arrangements for forest governance. This paper aims to assess the effects of alternative forest governance arrangements on the provision and economic values of forest ecosystem services (FES) in Vietnam. The study presents a framework for mapping land use and land cover (LULC) change stemming from actual and hypothetical changes in forest governance regimes, quantifies the resulting changes in the provision of FES, and estimates the associated economic values. In the context of the study site in the North Western uplands of Vietnam, we test three alternative forest governance scenarios: business as usual, with a dominant government role; a community-based governance regime; and a private, individual-based forestry governance regime. Scenarios are based quite closely on the way these regimes are (or might be expected to be) implemented in Vietnam. For each forest governance scenario, we map LULC changes based on land suitability analysis and transition likelihood for the period 2010 − 2020. The resulting maps are used as inputs into the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) model, which is used to estimate the quantity of three specific FES: carbon storage/sequestration, sediment yield, and water yield. We apply economic valuation methods to value these services: the social cost of carbon is used to estimate the economic values of carbon storage/sequestration; the cost of removing sediment deposited in reservoirs is applied for valuing the reduction of sediment yield, and the residual value of water supply for hydropower generation is used for valuing water yield. The results show that forest governance regimes have a significant effect not only on forest LULC, but also on the quantity and values of FES derived from forests. The FES are differentially affected by alternative forest governance regimes: some FES increase in quantity and value under some governance regimes and decrease under others. Of the three forest governance regimes examined, there is no one regime that will always be ‘better’ than the others in terms of provisioning all considered FES. For the specific context of Vietnam, we find that the private forest governance scenario is inferior to the community-based governance scenario, as an alternative to the current state-based governance. Because our results pertain to the scenarios as constructed, rather than generally to broad categories of governance regimes, there remains the possibility that regimes can be constructed that outperform all of those examined here.  相似文献   

4.
Many major agricultural regions worldwide are experiencing drastic landscape transformations. Examining the complex links among agricultural landscape dynamics (ALD), land use and land cover (LULC) change, socioeconomic development and government planning is pivotal to enhance the efficiency of agricultural landscape management. With a case of the Ningbo region (China), this paper employs the structural equation modeling (SEM) to quantify and compare the relationships between ALD and economic transition as well as the mediating LULC factors in different spatial planning zones. ALD are quantified by time series remotely sensed imageries and a set of landscape metrics; and economic transition is described by a set of indicators from three aspects (globalization, decentralization and marketization). Results show that ALD present similar trend in the two spatial planning zones between 1979 and 2013. However, the magnitude of ALD is larger in the non-urban planning zone. In particular, agricultural landscapes change into the fragmented, irregular, decreased, and isolated patterns at a more rapid pace. Economic transition drivers and LULC mediators differ remarkably between the two spatial planning zones. For the urban planning zone, economic transition influences ALD through construction land morphological changes and water body spatial density increases. For the non-urban planning zone, economic transition influences ALD through forest morphological changes and construction land spatial density increases. In addition, the relative importance of ALD determinants differs between the two spatial planning zones. Marketization plays a more critical role in driving ALD in the urban planning zone, while decentralization has a stronger impact on ALD in the non-urban planning zone. It is argued that land use master plan for agricultural landscape protection should be implemented in the non-urban planning zones and land use plan in the two spatial planning zones should be integrated. This study contributes to the understanding of the complex mechanism of ALD in response to economic transition.  相似文献   

5.
This paper reviews the relationships between land use and climate change. It explores how land use decisions will be affected by future changes in the climate, but also the feedbacks from land use change to the global climate system through greenhouse gas (GHG) fluxes. Past changes in land use were characterised by decreasing areas of agricultural use and increasing areas of forested and urbanised land. This has led to UK land use being a net sink for GHGs, mostly due to forestation. However, existing forests have on average passed their age for maximum net removals of carbon from the atmosphere. In the next decade at least, net removals from UK forests are likely to decrease significantly.Longer term scenarios of future land use change are consistent in their expectation of further declines in the agricultural area used for food production – offset to some extent by increased bioenergy cropping – along with increases in forested and urban areas. These trends are broadly consistent with the observed past land use change, but are calculated from various assumptions about future changes in drivers rather than by extrapolation from the past. Socio-economic and technological changes are likely to be the most important drivers for land use, with climate change having a smaller influence. The land use changes represented in these scenarios would likely reduce GHG emissions and enhance carbon sinks. These trends would be reinforced by small future changes in the climate, but large climatic changes are likely to cause net GHG fluxes to switch from being a sink to a source. Land use change will also be moderated by potential policy goals that seek to reduce GHG emissions from land and/or increase the size of land-based sinks. This includes strategies to reduce carbon and nitrogen emissions through increased efficiency, afforestation and biofuel production.  相似文献   

6.
Agricultural land abandonment and the consequent natural forest regrowth in areas once cultivated has significantly transformed Alpine ecosystems and landscapes. In this paper, we estimated the loss of agricultural areas due to reafforestation in the Belluno Province (Eastern Italian Alps) and integrated socioeconomic indicators with topographical features to evaluate the drivers of this change. Land use mapping, obtained from photo-interpretation of aerial photographs and technical maps, was used to quantify changes in forest and agricultural areas (crops, meadows and pastures) during the period of 1980–2000. On average, the forest surface expanded by 21%, while the agricultural areas decreased by 40%. This loss increased in areas with steeper slope, which confirms that the areas that would be first abandoned are those that are less productive and more difficult to manage. The reafforestation rate was particularly strong in the north of the province, where the livestock sector experienced a dramatic decline. In light of this situation and using multiple regression models with a large set of socioeconomic and agricultural indicators, we found that the loss of agricultural areas in 69 municipalities was primarily counterbalanced by the maintenance of livestock farming. The loss of steeper agricultural areas was counteracted by traditional extensive systems; however, it was not counteracted by modern intensive systems, which has important implications because steeper areas have higher landscape and biodiversity values. In addition, tourism development had a positive, although smaller, effect on the maintenance of agricultural areas, while industry development had a negative effect. The results of this study suggest that efforts are needed to maintain a territorial network of traditional extensive farms to avoid further landscape deterioration in Alpine areas. Likewise, certain choices toward the economic development of local communities might have an impact on land conservation.  相似文献   

7.
Land use change, climate change, and the politics of accelerated agricultural growth shape contemporary land use in Russia. This factor combination urgently calls for exploring viable opportunities for sustainable land management in rural areas, which remains low on the political agenda. We address this task by bringing together various dimensions of future land use and state regulation and develop land use scenarios for the Tyumen region in Western Siberia up to 2050. Schematised maps of future land use make the scenarios spatially explicit and stakeholder-engaging. As part of the scenario process, we conducted stakeholder interviews and organised two scenario workshops on the ground. We present the scenarios as a tool that could be used to support participatory processes in a post-Soviet context.  相似文献   

8.
Agricultural decline may pose an important threat to mountain biodiversity but it also constitutes a driving force of socio-economic transformation. The aim of this study is to investigate the implications of alternative agricultural policy scenarios on the sustainable development of Greek mountain areas using a case study approach (Zagori region, Greece). Two agricultural policy scenarios were explored and assessed against a list of sustainability objectives. Causal relationships among drivers of changes and sustainability objectives were explored using Network Analysis. Our analysis has shown that agricultural liberalisation is expected to have devastating effects on the development of the area and it was strongly opposed as an alternative future by the local stakeholders. The analysis of the driver's causal relationship has also revealed that in order to ensure the sustainable development of the area it is necessary to sustain low input extensive farming, to promote mild tourism development and to enhance the operational efficiency of the National Park. Moreover, in order to reconcile agricultural decline, biodiversity and sustainable development, policy-management recommendations must be drawn at multiple administrative levels and complementary policy interventions within and between levels are required. It is thus, important that EU agricultural policies are complemented by national-regional interventions in order to regulate the fragile balance between agriculture and tourism. Finally, this study has shown that the combination of scenario analysis and sustainability assessment can provide an efficient tool to inform management strategies for sustainable development.  相似文献   

9.
Humans have altered land cover for centuries, and land-cover change is a main component of global change. Land use transition trajectories, such as the forest transition theory (i.e. switch from deforestation to stable or increasing forest cover), relate long term changes in land use to gradual changes in underlying drivers, such as economic development, demographic change, and urbanization. However, because only few studies examined land change over centuries, it is not clear how land cover changes during very long time-periods which are punctuated by shifts in socio-economics and policies, such as wars. Our goal here was to examine broad land change patterns and processes, and their main driving forces in Central and Eastern Europe during distinct periods of the past 250 years. We conducted a meta-analysis of 66 publications describing 102 case study locations and quantified the main forest and agricultural changes in the Carpathian region since the 18th century. These studies captured gradual changes since the peak of the Austro-Hungarian Empire up to the accession to the European Union of most of the formerly socialist countries in the study region. Agricultural land-use increased during the Austro-Hungarian Empire in 70% of the case studies, but dropped sharply during and especially after the collapse of the Socialism (over 70% of the cases). The highest rates of abandonment occurred between 1990 and 2000. The Carpathian region experienced forest transition during the Interwar period (93% of the cases), and the forest expansion trend persisted after the collapse of Socialism (70% of the cases). In terms of the drivers, institutional and economic factors were most influential in shaping deforestation and agricultural expansion, while socio-demographics and institutional shifts were the key drivers of land abandonment. Our study highlights the drastic effects that socio-economic and institutional changes can have on land-use and land-cover change, and the value of longitudinal studies of land change to uncover these effects.  相似文献   

10.
Understanding the capacity of agricultural systems to feed the world population under climate change requires projecting future food demand. This article reviews demand modeling approaches from 10 global economic models participating in the Agricultural Model Intercomparison and Improvement Project (AgMIP). We compare food demand projections in 2050 for various regions and agricultural products under harmonized scenarios of socioeconomic development, climate change, and bioenergy expansion. In the reference scenario (SSP2), food demand increases by 59–98% between 2005 and 2050, slightly higher than the most recent FAO projection of 54% from 2005/2007. The range of results is large, in particular for animal calories (between 61% and 144%), caused by differences in demand systems specifications, and in income and price elasticities. The results are more sensitive to socioeconomic assumptions than to climate change or bioenergy scenarios. When considering a world with higher population and lower economic growth (SSP3), consumption per capita drops on average by 9% for crops and 18% for livestock. The maximum effect of climate change on calorie availability is ?6% at the global level, and the effect of biofuel production on calorie availability is even smaller.  相似文献   

11.
It remains challenging to derive general findings and conclusions from either economic theory or empirical studies on the relationship between international trade and the regional environment. Consequently, we aim to analyse environmental effects of agricultural trade policies in the Austrian Marchfeld region. We apply an integrated modelling framework that accounts for heterogeneity in agricultural production and environmental outcomes. Scenario analysis is applied to assess regional impacts of different trade policy scenarios. Sensitivity analyses reveal the relative influence of model parameters on outputs. The results indicate that lower domestic tariffs have small beneficial effects on the regional environment. The regional environmental impacts highly depend on the changes in world crop prices through global trade agreements. A laissez-faire market scenario that includes the elimination of trade barriers and agri-environmental payments (AEPs) leads to substantial environmental deterioration. Hence, the alignment of AEPs with WTO trading rules remains an important issue in the trade and environment debate.  相似文献   

12.
In the complex agro-ecological conditions of Vietnam's northern borderlands, attempts by ethnic minority farmers to create sustainable livelihoods, along with the impacts of state development policies, have direct consequences for land use and land cover (LULC) change. In this paper we analyse the degree to which LULC has changed and diversified from 1999 to 2009 in Lào Cai Province and the underlying relationships with ethnic minority livelihood diversification strategies. We examine the correlation between LULC diversity and various socioeconomic and biophysical proxies using a spatial autoregressive model. Our findings indicate two major changes in LULC: an increase in closed canopy forest and substantial urban growth. LULC diversity increased between 1999 and 2009, suggesting a transition between land uses and/or a diversification of livelihood strategies. Socioeconomic proxies are significant predictors of LULC diversity in both years, while biophysical proxies are only effective predictors in 2009. In-depth interviews regarding state-led policies and ethnic minority livelihoods reveal some of the underlying mechanisms of such LULC transitions and associations.  相似文献   

13.
Changes in agricultural land use have important implications for environmental services. Previous studies of agricultural land‐use futures have been published indicating large uncertainty due to different model assumptions and methodologies. In this article we present a first comprehensive comparison of global agro‐economic models that have harmonized drivers of population, GDP, and biophysical yields. The comparison allows us to ask two research questions: (1) How much cropland will be used under different socioeconomic and climate change scenarios? (2) How can differences in model results be explained? The comparison includes four partial and six general equilibrium models that differ in how they model land supply and amount of potentially available land. We analyze results of two different socioeconomic scenarios and three climate scenarios (one with constant climate). Most models (7 out of 10) project an increase of cropland of 10–25% by 2050 compared to 2005 (under constant climate), but one model projects a decrease. Pasture land expands in some models, which increase the treat on natural vegetation further. Across all models most of the cropland expansion takes place in South America and sub‐Saharan Africa. In general, the strongest differences in model results are related to differences in the costs of land expansion, the endogenous productivity responses, and the assumptions about potential cropland.  相似文献   

14.
Land use change at the local stage affects the flow of ecosystem services at all levels. Analyzing the causes of land use change such as anthropogenic activities in the case of the Ourika watershed will facilitate sustainable policies. A decision-making tool, InVEST (Integrated Valuation of Ecosystem Services and Trade Offs) was used to quantify three ecosystem services and to generate three spatially explicit land use scenarios (trend, development and conservation) with expert stakeholders and the local population. The results indicate that forest expansion under the conservation scenario increased carbon sequestration and sediment retention by 34.29 % and 7.17 % but decreased water yield by 0.75 %. Comparably, a combination of forest and cropland expansion under the trend scenario generated a moderate increase by 8.4 % and 0.98 % but a negligible decrease of 0.09 %. A decline in the forests under the development scenario caused an improvement in the water yield by 0.12 % but a decrease in carbon sequestration and sediment retention by 6.06 % and 0.88 % respectively. A combination of forests and croplands through agroforestry systems enhances the provision of all the three ecosystem services. Community-based ecosystem and land management is the best way to improve ecosystem services at the local level.  相似文献   

15.
In this paper, we apply qualitative methodologies to explore the practice of interdisciplinary research. The UK's Rural Economy and Land Use (RELU) Programme aims to advance understanding of the challenges faced by rural areas through funding interdisciplinary research to inform future policy and practice on management choices for the countryside and rural economies. Addressing the challenges faced by rural areas often requires a combination of different perspectives, involving research to address subjects that may lie beyond the skills of individual researchers. An interdisciplinary approach requires the integration of both data/information and the experiences and perspectives of different people (natural/social scientists, local people and policy‐makers). We focus here on the processes involved in making interdisciplinarity work, documenting the experiences, perceptions, ideas and concerns of researchers working in interdisciplinary projects (specifically two EU‐funded projects but also the first wave of RELU projects). A key finding from this research is that interdisciplinarity requires conscious effort, time and resources for the development of interpersonal relationships to enhance effective communication and thus successful collaboration.  相似文献   

16.
Changes in land cover of protected areas and their buffers have serious implications on the conservation of biodiversity within such biomes because land use has been recognized as one of the major drivers of biodiversity change. Atewa Range Forest Reserve is one of Ghana's Upper Guinea Forests declared as a Globally Significant Biodiversity Area (GSBA). But the reserve is under threat from several human disturbances which could impact on the land cover of the reserve.This study examined the spatial and temporal changes in land cover of Atewa Range Forest Reserve and it's buffer between 1986 and 2013 using remote sensing. Land use and land cover (LULC) classification and change detections were undertaken using one Landsat Multispectral Scanner (MSS) image of 1986 and Landsat ETM+ images of 2003 and 2013.The study also investigated the driving forces of LULC and the effectiveness of the Forest and Wildlife Policy of 1994 in the management of the reserve.Results of image classification showed that much of the peripheral closed and open vegetative covers have been converted to farms and bushes with little disturbance within the interior of the reserve. The study revealed that, the conservation management policies were yielding very little results due to a number of policy deficiencies including low staff strength, lack of logistics and low remuneration. Enforcement of legal instruments against illegal logging, small scale mining and farming activities within the reserve, improvement in the staff strength and their condition of service, intensification of public education on the value of forest and the need to protect it are some of the major recommendations that could curb encroachment on the reserve.  相似文献   

17.
The UK exited the EU on 31 January 2020, with a transition period agreed as part of the Withdrawal Agreement. During this transition period the UK and the EU will decide on their future trading relationship. No matter what form this relationship takes, there will be disturbances to agri‐food markets. This study analyses four different scenarios with increasing barriers to trade, ranging from a very close relationship similar to the European Economic Area to a distant relationship in which the UK and EU trade on Most Favoured Nation terms, using the EU focused global agricultural sector model CAPRI. In the UK, food prices will increase in all scenarios, making consumers in the UK the biggest losers. Only in a free trade agreement scenario does the UK show an unambiguous positive net welfare gain in just the agri‐food sector. In the case of the European Economic Area scenario, which assumes continued access to the single market, the net welfare impact would depend on the size of the UK’s continued contribution to the EU. In the EU, declining food prices would benefit consumers but the sum of the loss in farmers’ incomes and the UK’s EU CAP contribution would be much greater than the consumer’s gain. These impacts in agricultural markets under different future trade arrangements will also be influenced by the UK’s agricultural policy changes in direct payments as well as by possible further UK trade liberalisation after the end of the transition period.  相似文献   

18.
The region connecting Edmonton and Calgary, the two largest cities in Alberta, contains rich agricultural land and is one of the most rapidly changing areas in the province. There is little legislation to restrict urban sprawl or adequately protect agricultural land or native grasslands, and there has been little research to predict future alteration. The main study objectives are, therefore, to assess historical changes in the Edmonton-Calgary corridor from 1984 to 2013 and simulate the future landscape change to 2022 under potential government intervention scenarios. Satellite imagery from Landsat, used in conjunction with biogeophysical variables, was used to create a history of cover in the Edmonton-Calgary area. This history of the environment can be used as a baseline to project changes into the future. Testing different legislative scenarios under two major branches of modifying rates of change or locations of change can be used to identify effective policies for limiting damage to the environment while still allowing for urban growth. Five scenarios were created for this purpose: (1) business as usual, (2) increased rate of urban expansion, (3) no urban expansion, (4) implementation of greenbelts around urban areas, (5) protection of the best agricultural land. This study finds that over the past 30 years, urban area has nearly doubled in size, targeting predominately farmland, especially due to an increase in rural subdivisions. Each scenario impacts growth differently, however, greenbelts and the no expansion model decease growth the most, while the agricultural protection is comparable to the business as usual scenario.  相似文献   

19.
This article highlights the main changes observed in Brazilian agriculture and analyzes the connections of the observed changes in global agriculture. My approach to the analysis focuses the main drivers of changes, where institutions play a central role. Three driving forces are are considered: first, the effects of global demand for food, fiber, and energy; second, the sustainability debate; and third, the bio‐energy paradigm. Each driver presents both local as well as global effects. The article does not emphasize the impact changes in Brazil had on the global agricultural landscape but argues that the impacts run from local and global changes, which cannot be discussed separately.  相似文献   

20.
In this study, we analyse how three scenarios involving different levels of harmonisation of common agricultural policy (CAP) decoupled payments in the EU affect the distribution of farm income across regions and farm types. We use the farm type extension of the common agricultural policy impact (CAPRI) model, which captures farm heterogeneity across the EU. The first scenario (NUTS1) assumes uniform per‐hectare payments at the NUTS1 level. The second scenario (MS‐CONV) equalises the per‐hectare rates inside each Member State (MS) and partially harmonises the single payment scheme (SPS) across MS in line with the 2011 Commission proposal. The third scenario simulates a uniform per‐hectare payment at the EU level. Depending on the implementation of the SPS, the NUTS1 flat rate induces a substantial redistribution of payments across farm types and NUTS2 regions, particularly in regions that apply the historical SPS. The MS‐CONV and EU flat‐rate schemes have more significant impacts at the EU‐wide level. In the EU‐15, almost all farms lose payments from MS‐CONV and EU‐wide flat rates, whereas in the EU‐10, almost all farm types gain from these scenarios. Our conservative estimates indicate that the flat‐rate payments could redistribute up to €8.5 billion. Lower land rental costs partially offset the losses of farm income in the EU‐15 from payment redistribution. Land rents drop for all flat‐rate scenarios across most sectors and farm sizes in the EU‐15. In the less productive new MS, the landowners’ rental income is largely unaffected by the introduction of the flat rate.  相似文献   

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