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The paper introduces and discusses an open-source spatial-based model (called r.green.solar) able to quantify the energy production from solar photovoltaic (PV) ground-mounted panels. Socio-economic and environmental impacts can be evaluated by the model. The model starts from the theoretical quantity of solar PV potential energy and estimates a reduction of total amount of energy based on legal, technical, recommended and economic constraints. Model outputs were used for a trade-off analysis between energy production and traditional crops for food/feed cultivation on not irrigated arable land. The model was tested at regional level for a Mediterranean context (Italy). The results confirm that the economic profitability of PV systems follows a north-south gradient, but the main impacts are related to local peculiarities – such as the disposal of not irrigated arable land and the presence of constraints, in particular the landscape maintenance, the morphological variables and the specialization index – and crop yields.  相似文献   

3.
Using a simple neoclassical type growth model including both man-made and natural capital as inputs to production, the theoretical basis for a U-shaped relationship between agricultural intensification and farm household investment in renewable resource capital is established. As development of technology, infrastructure, or markets increase the relative return to investment in man-made capital over natural capital, resource depletion occurs as man-made capital is substituted for lower return natural capital. Once returns are equalized, both man-made and natural capital are accumulated. If labor and these forms of capital are complementary, the output effects outweigh the substitution effects in the long run, leading to net accumulation of natural as well as man-made capital as a result of such technological or market development. Population growth also induces investment in both man-made and natural resource capital in the long run by increasing their marginal products. However, population growth causes declining per capita levels of both natural and man-made capital and production per capita in the long run, if technology is fixed and decreasing returns to scale. The model thus supports the Boserupian argument of induced intensification and resource improvement, as well as the Malthusian argument of the impoverishing effects of population growth. However, population growth may also induce development of infrastructure, markets, and technological or institutional innovation by reducing the fixed costs per capita of these changes, though these developments may not occur automatically. Government policies can play a large role in affecting whether these potential benefits of population growth are realized. In addition, credit policies may reduce resource degradation caused by substitution of man-made for natural capital, by allowing farmers to accumulate man-made capital (such as fertilizers) without depleting their natural capital. Policies to internalize the external environmental costs of using man-made capital will reduce both types of capital and production, indicating a clear trade-off between addressing environmental concerns on the one hand and reducing poverty and promoting resource conservation investments on the other. By contrast, internalizing the external benefits of investments in resources increases wealth and production per capita in the long run. The ‘intertemporal externality’ due to a higher private than social rate of time preference does not justify interventions to promote investments in resource capital; rather it argues for the promotion of savings and investment in general.  相似文献   

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Land use change is strongly modifying the traditional landscape of hilly productive Mediterranean sites. An example of these circumstances is the Langhe region (Piemonte, NW Italy), where woody plantations such as vineyards and orchards have been cultivated on hillslopes for centuries. In this paper we assess landscape changes occurred in the Diano study area (2651 ha) in the 1954–2000 period and we ascertain land use transition paths and rates of this rural ecosystem. Land use mapping obtained from object-oriented analysis of aerial photographs was used to quantify land use changes between 1954 and 2000. To examine the spatio-temporal patterns of land use change over time, a set of spatial statistics capturing different dimensions of landscape change was identified. An increase of landscape heterogeneity from 1954 to the present was observed due to the expansion of orchards and the fragmentation of field crops. A significant portion (55%) of current orchards surface is represented by former field crops, 24% by vineyards and 15% by forests. The strong expansion of hazelnut orchards concurred to the fragmentation of traditional rural landscape was dominated by vineyards, field crops and forests. Hazelnut orchards expansion was mainly located in places where grapes cultivation was less remunerative. A further expansion of hazelnut in the area should be planned, discussed and carefully monitored through change detection studies in order to avoid potential unsustainable use of the land.  相似文献   

6.
Quadratic programming techniques were applied to household food consumption data in England and Wales to estimate likely changes in diet under healthy eating guidelines, and the consequences this would have on agriculture and land use in England and Wales. The first step entailed imposing nutrient restrictions on food consumption following dietary recommendations suggested by the UK Department of Health. The resulting diet was used, in a second step as a proxy for demand in agricultural commodities, to test the impact of such a scenario on food production and land use in England and Wales and the impacts of this on agricultural landscapes. Results of the diet optimisation indicated a large drop in consumption of foods rich in saturated fats and sugar, essentially cheese and sugar-based products, along with lesser cuts of fat and meat products. Conversely, consumption of fruit and vegetables, cereals, and flour would increase to meet dietary fibre recommendations. Such a shift in demand would dramatically affect production patterns: the financial net margin of England and Wales agriculture would rise, due to increased production of high market value and high economic margin crops. Some regions would, however, be negatively affected, mostly those dependent on beef cattle and sheep production that could not benefit from an increased demand for cereals and horticultural crops. The effects of these changes would also be felt in upstream industries, such as animal feed suppliers. While arable dominated landscapes would be little affected, pastoral landscapes would suffer through loss of grazing management and, possibly, land abandonment, especially in upland areas.  相似文献   

7.
We analyse food demand patterns of Indonesian households from a resource intensity perspective and quantify the impact of changed demand patterns on the use of three major resource inputs: fossil fuel; land; and water in agricultural production. Using Indonesian Family Life Survey data, 13 major food items (which constitute 70 per cent of food expenditure) are categorised into low, moderate and high resource intensity, and income elasticity and Engel curves are estimated for the period from 1997 to 2007. Our results show that income growth in Indonesia is associated with demand patterns that are more resource intensive. By 2007, per capita requirements of fossil fuel, land and water increased by 42.7 per cent (3.13 MJ), 44.9 per cent (1.24 m2) and 50.4 per cent (2.1 kL), respectively, relative to 1997. The results imply that, at least for Indonesia, changed food demand patterns resulting from economic development will increase the demand for natural resources substantially.  相似文献   

8.
Increasing landholder participation in environmental programmes is often essential for achieving desired levels of restoration and protection, as well as the economic goals of efficiency and equity. Previous literature has identified sociodemographic property and attitudinal variables that influence participation. Using qualitative research, we identify variables relating to human capital (business orientation and information seeking behaviour) and social capital (trust in those delivering programmes and connectedness with other landholders) that have been seldom or never identified as influencing participation. New scales are developed and existing scales refined for measuring these constructs, and their influence on past and future participation is examined together with a range of other constructs. The effect of these variables is examined using a survey of Australian landholders, and the results demonstrate the primacy of variables relating to human and social capital in influencing past and future participation.  相似文献   

9.
Urban development induced land transitions affect urban hydrology, resulting in increased flooding risks. Climate change-related precipitation changes are an added complexity to the flood risks of cities. This study examines the role of land use changes in determining the occurrence of urban flooding events across 42 Indian cities under current and future climate change scenarios. Landsat images for 1990, 2000, 2010, and 2017 have been processed using a hybrid classification technique to determine the land use shares for all cities. A typical event-count study using newspaper archives has been conducted to create a flooding event database. A multilevel model employing logistic mixed-effects approach was used. Future projections of the occurrence of flooding events for nine models under three climate change-related Representative Concentration Pathways (RCPs)—2.6, 4.5, and 8.5—and three urban development scenarios have been carried out. The results suggest that cities should preserve the land uses that act as a sponge—the green, open and blue spaces. As these spaces decrease, the projected flooding events increase. Under the RCP 2.6 scenario, the number of flooding events is significantly lower (95 % confidence) than under RCPs 4.5 and 8.5. The expected flooding occurrences between RCP4.5 and RCP8.5 are not significantly different (95 % confidence) for many scenarios, suggesting that Indian cities should aim for a world temperature increase of below 2 °C, or devastating consequences are imminent. This study highlights the need for Indian cities to undertake integrated spatial planning measures for a resilient, sustainable urban future.  相似文献   

10.
The expert-based approach to landscape assessment developed in North America during the 1970s is still largely used in planning. It has proved its usefulness for the protection and the management of landscapes with remarkable visual attributes. However, facing growing social demands for the quality of surroundings, ordinary landscapes also raise great challenges for planning. But, to what extent is the expert-based approach to landscape assessment able to capture the value of these ordinary landscapes? What might be the more appropriate method for this purpose? This paper addresses these questions through an empirical research project in areas of intensive agricultural use in Quebec (Canada). The aim of this research was to measure and compare the ability of an expert-based approach and of a lay people-based approach, also named experiential approach, to capture the most valued components of ordinary landscapes. These methods were applied to two study areas. The first one has no recognised landscapes in any planning document while the second one has recognised landscapes for regional tourism. Forty-six inhabitants and an expert were invited to evaluate the landscapes of the study areas. The results have allowed comparison of the components valued by the expert and by the inhabitants as well as the criteria used in the assessment. They revealed differences between the expert and the lay people assessment. For inhabitants, the value of ordinary landscapes is based on a set of criteria related to emotion, to everyday experience and to their intimate knowledge of places. Thus, the formal visual criteria used by the expert appear to be clearly less important in the evaluation by lay people. As the expert perspective in landscape assessment is more closely associated to the experience of an individual which cross the territory (ex.: tourist), this paper concludes that to capture the value of ordinary landscapes in a planning perspective, a combination of approaches is necessary.  相似文献   

11.
This empirical study uses 100 years of annual data on 11 agricultural commodities from Belgium to measure the impact of structural changes coinciding with economic development and changes in political institutions on agricultural protection. The analysis shows that changes in agricultural protection are caused by a combination of factors. Governments have increased protection and support to farmers when world market prices for their commodities fell, and vice versa, offsetting market effects on producer incomes. Other economic determinants were the share of the commodities in total consumer expenditures (negative effect) and in total output of the economy (positive effect). With Belgium a small economy, there was no impact of the trade position. Changes in political institutions have affected agricultural protection. Democratic reforms which induced a significant shift in the political balance towards agricultural interests, such as the introduction of the one‐man‐one‐vote system, led to an increase in agricultural protection. The integration of Belgian agricultural policies in the Common Agricultural Policy in 1968 coincided with an increase in protection, ceteris paribus. Both institutional factors, related to changes in access to and information about the decision‐making at the EU level, and structural changes in the agricultural and food economy may explain this effect.  相似文献   

12.
Credibility of institutions: Forestry, social conflict and titling in China   总被引:2,自引:0,他引:2  
Peter Ho   《Land use policy》2006,23(4):588-603
In the reform of a forestry sector governed by centralist, socialist principles towards a sector suited to the challenges of the market economy, the Chinese government needs to establish institutions that can be perceived as credible by social actors. In other words, the creation of institutions that rally sufficient social and political support in order to be effective. Against this backdrop, this article consciously opts to refer to institutional “credibility” instead of the more fashionable concept of institutional “trust”. Whereas scholarly discussions about trust focus more on the relation of trust between social actors, credibility puts more emphasis on the institution itself, and the role of government in its successful creation or failure. Failure to effectively undertake institutional reform might put the social acceptability or credibility of institutions at risk, and can lead to the emergence of “empty institutions” with little, or even, a negative effect on social and political actors. Applying this concept to China's forestry sector, this article identifies three critical areas that call for careful rethinking how to “get institutions right”: the titling of forest holdings; the restructuring of the forest administration; and the design of forest laws and policies with particular reference to lease and ownership.  相似文献   

13.
One component of biosecurity is protection against invasive alien species, which are one of the most important threats worldwide to native biodiversity and economic profitability in various sectors, including agriculture. However, agricultural producers are not homogeneous. They may have different objectives and priorities, use different technologies, and occupy heterogeneous parcels of land. If the producers differ in terms of their attitude towards invasive pests and the damages they cause, there are probably external effects in the form of pest spread impacts and subsequent damages caused. We study such impacts in the case of two producer types: profit‐seeking professional producers and utility‐seeking hobby producers. We show that the hobby producer, having first set a breeding ground for the pest, under‐invests in pest control. We also discuss potential policy instruments to correct this market failure and highlight the importance of considering different stakeholders and their heterogeneous incentives when designing policies to control invasive alien species.  相似文献   

14.
This study analyses the impacts of de-coupling of agricultural support from production in Finland. A dynamic agricultural sector model, which includes 17 production regions and endogenous investments and technical change, is used in the analysis. Investment in different production techniques is dependent on the relative profitability and the spread of each technique in the population of heterogeneous farms. There are relatively few large farms which use efficient production techniques in Finland. De-coupling weakens the incentive for investment in dairy production and causes a temporary but significant slow down in dairy investments and technical change. Consequently, de-coupling is likely to result in a significant drop in milk and beef production in the next 10-20 year period if no corrective measures are taken in agricultural policy in less-favoured areas such as Finland. However, a slow recovery of investment and output levels are expected in the long run.  相似文献   

15.
In recent years, numerous articles have addressed management strategies aimed at assisting forests to adapt to climate change. However, these seldom take into account the practical and economic implications of implementing these strategies, notably, supply of forest plants and seed. Using semi-structured interviews with practitioners involved in the plant and seed supply chain in Great Britain, we highlight a series of practical and economic bottlenecks commonly encountered in the supply of locally sourced seed and domestically produced planting stock for native woodland and hedging markets. We find that adoption of alternative seed sourcing strategies, designed specifically to account for directional climate warming, is likely to exacerbate existing problems by adding further complexity to decisions nurseries make about tree species and seed origins to produce. The lack of long-term market predictability brought about by the current configuration of forestry grants and regulations and, in particular, the administrative systems for processing grant applications is identified as a major impediment to having a sustainable and competitive supply of home-grown and currently adapted planting stock. Finally, the time and effort it takes to supply healthy plants for native woodland creation projects deserves much wider recognition throughout the industry and will be crucial if planting objectives are to be met sustainably.  相似文献   

16.
This article reports findings from a simulation model representing the European farming system disaggregated at different scales. This modeling experiment explores the effects of various decoupling options associated with the 2003 European agreement on gross margins, land use, shadow cost of land, and greenhouse gas emissions. Our results show increases in the farmers’ gross margins when decoupled support is maintained equal to the amount of direct aid previously attributed to agricultural production, assuming unchanged prices. Land used for pasture increases at the expense of land used for cereals and protein crops. The extent to which these effects materialize depends on the policy options selected by Member States when implementing the Luxembourg agreement. When they opt for some recoupling of support, adverse net economic impacts occur for producers. Regional differences in impacts are more pronounced than the analysis aggregated at European and national scales suggests. This highlights the need for further work based on geostatistical downscaling.  相似文献   

17.
Urban sprawl is considered by most environmental scientists and urban planners to be a serious environmental problem. However, public perception about parking availability often forces planning offices to recommend parking lot sizes that exceed daily demands. The recent trend of increasing the size of stores, churches and even schools comes with increasing the size of parking lots that service these buildings. The objective of this paper is to analyze space allocation of parking lots in a typical midwestern county and to estimate the supply of parking spaces to potential demand. We also estimate the loss of ecosystem services represented by the area of parking lots in this county. We found that parking lots cover 5.65 km2 (1 397 acres) of Tippecanoe County, Indiana which implies that 0.44% of the county area is devoted to parking lots. Our results show that there are approximately 2.2 parking spaces per registered vehicle, that parking lots make up more than 6.57% of the total urban footprint in this county, that the area of parking lots exceeded the area of parks in the city limits by a factor of three and that parking lot runoff and pollutants are significant compared to runoff and pollutants from these areas prior to their conversion to parking lots. As other authors have done before us we lament the poor use of land in urban regions of the United States, and encourage planners to think creatively about the use of land for parking.  相似文献   

18.
A multivariate probit (MVP) model was used to analyse the determinants of strategies adopted for adapting to climate change in a sample of smallholder rice farmers in south-west Nigeria. An efficient endogenous switching regression model (ESRM) was used to estimate the impact of climate change adaptation strategy on the net income of rice farmers. The MVP results show that the socio-economic factors, the institutional factors, and locational variables of some households statistically influenced the choice of climate change adaptation strategies employed. Complementarities among all the adaptation strategies used by the farmers were revealed by the positive pair-wise correlation matrix of the MVP model. The study also indicated that farmers affected by prolonged drought and incidences of flood were more likely to adopt adaptation strategies on their farmlands. The ESRM treatment effect indicated that the average net income per rice farm of those who adopted the strategies was significantly higher than that of those who did not. Thus, the government, stakeholders, and donor agencies must provide capacity-building innovations related to agricultural extension systems and climate change education through information and communication technologies. This investment in education is essential for development and would encourage farmers to adopt appropriate climate change adaptation strategies.  相似文献   

19.
The environmental, cultural and economic consequences of land use change, including abandonment of agricultural use, have been recognized for a long time. It has often been assumed that the transformations of the agricultural systems in developed countries (and particularly in Europe) took place, for the main part, in the immediate years after the Second World War. In this paper we present a review of different statistical and cartographic sources available for a peripheral region in Europe (Galicia, Spain) characterized by small-scale farming and a very fragmented property system, that suggests otherwise: modernization of agriculture apparently took place without major changes in agricultural area until the country gained access to the European Economic Community, and the effect of Common Agricultural Policy reforms during the decade of 1990 is suggested as a major driver for the net decrease of agricultural area in the region between 1956 and 2004. On the other hand, this paper emphasizes the spatial complexity of agricultural abandonment with a case study, showing a large degree of variability at municipal scale and thus the need of future EU-level projects to work at least at municipal (Local Administrative Units 2, LAU 2) level. Finally, a multinomial logistic model for observed changes is included that shows how biophysical limitations were the main drivers behind abandonment of agriculture at parcel scale, while structural qualities related to property structure were strongly associated to the incorporation of former shrublands to agricultural use. Besides, Farm Structure Surveys were revealed as an unreliable source for the assessment of changes in total agricultural area in the studied region.  相似文献   

20.
Increased pressure on ecosystems and enhanced competition over the use of natural resources makes it necessary to develop sustainable methods for natural resource management (NRM). However, NRM is a complicated issue. It involves numerous stakeholders, with different needs, resources and perceptions of nature. Stakeholder participation will necessarily be selective, based both on theoretical assumptions about who is a legitimate stakeholder and unevenly distributed power among stakeholders. Although stakeholder involvement is important, sometimes the theory appears to be rather blunt. It has been suggested that, since different categories of stakeholders embody different perceptions of nature, cultural theory could provide important additional criteria for stakeholder involvement. Based on field studies in Naivasha, Kenya, this paper analyses pros and cons of stakeholder analysis and investigates the usefulness of cultural theory for improved stakeholder analysis.  相似文献   

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