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1.
We examine dramatic cropland expansion in Karamoja, Uganda by investigating the links between biophysical and political historical events leading to the current state of agricultural land use. Our objective was to quantify agricultural expansion, uncover the dominant drivers leading to the current state of agricultural land use and its impacts on livelihoods. Region wide analysis of remotely sensed data, land use policy and history as well as farmer interviews were undertaken. We posit that government programs instituting sedentary agriculture are the most significant drivers of cropland expansion in Karamoja. We show a 299% increase in cropland area between 2000 and 2011 with most expansion occurring in Moroto District (from 706 ha to 23,328 ha). We found no evidence of an increase in overall crop production or food security and food aid continues to be essential due to recurrent crop failures. Due to lack of resources for inputs (e.g., seeds and labor) cultivated fields remain very small in size and over 55% of once cultivated land is left fallow. Our findings bring into question whether continued promotion of rain-fed agriculture in Karamoja serves the best interests of the people. Current cropland expansion is directly competing and compromising pasture areas critical for livestock-based livelihoods. Without strong agricultural extension programs and major investments in climate-smart options, cropland expansion will continue to have a net negative impact, especially in the context of current climate projections which indicate a future decrease in rainfall, increase in temperature and an increase in the frequency and magnitude of extreme events. 相似文献
2.
Urbanization results in increasing impervious surfaces with the potential to threaten fragile environments and heighten flood risks. In the United States, research on the social processes driving urbanization has tended to focus on the twenty-first century, but less is known about how temporal trends arose from the spatial layout of the urban land upon which this growth was founded. To address this gap, we present a novel interdisciplinary synthesis using neighborhood-level census data in tandem with a satellite-derived annual land cover change time series to assess the role of race, affluence, and socioeconomic status in shaping spatio-temporal urbanization in the Houston metropolitan area from 1997−2016. Results from cross-sectional and temporal regression models indicate that while social dynamics associated with historical versus recent urbanization are related, they are not identical. Thus, while temporal change in Houston's urbanization is driven primarily by socioeconomic status, the social dynamics associated with spatial disparities in urbanization relate primarily to race, regardless of socioeconomic status. These results are noteworthy as urbanization in Houston does not fully comport with existing theoretical perspectives or with empirical findings nationally. Instead, we suggest these findings reflect the city’s politics and culture surrounding land use. Thus, beyond its important social and environmental implications, this study affirms the utility of fusing socio-demographic data with satellite remote sensing of urban growth, and highlights the value of the socioenvironmental succession framework for characterizing urbanization as a recursive process in space and time. 相似文献
3.
The Okavango catchment is a hot spot of accelerating land use change. In particular, climate predictions, demographic developments and a growing utilization of ecosystem services and functions are expected to increase pressure on resources and land. Land use conflicts, the sustenance of precarious livelihoods, deforestation of woodland savannahs, upstream–downstream water issues and human–wildlife conflicts are among the processes that are characteristic of policy and management challenges in the region. In the Eastern and Western Kavango regions of Namibia and the Cuando-Cubango province of Angola, a unique cross-border situation exists that allows assessing how the combination of local traditions, regional land management and national policies determines spatial patterns of land use and land cover transformation processes.To map major land use types and change processes we used a set of multi-temporal Landsat-5 TM and Landsat-7 ETM+ data sets, support vector machine (SVM) classification and iterative spectral mixture analysis (ISMA) on images covering the period from 1990 to 2010. Integrating satellite imagery with literature reviews, interviews, census and household survey data, we assessed the contrasting development of resource utilization on both sides of the Okavango River. We investigated if and how policies and regulations at different levels drive land use decisions, and how these decisions manifest spatially.We found a strong and interconnected urban growth on both sides of the river. The area around Rundu has constantly been evolving to become Namibia's second largest city, also functioning as a hub of development and transborder commerce with opposing Calai. This trend was found to affect adjacent settlement areas and cause widespread conversion of woodland savannahs to agricultural land or their utilization for timber extraction. The conversion of woodland savannah to arable land was by far the dominant land use change process on both sides of the river, with a total conversion area of 460 km2 (Namibia) and 293 km2 (Angola) observed during the observation period. Strong spatial change gradients occurred in relation to determining factors, such as accessibility, proximity to water, urban centres, etc., while relations to settlements where less obvious. Assessing results by country illustrated the difference in land use intensity and resource consumption between Angola and Namibia, which relate directly to historical developments, with a long period of stability in Namibia standing opposed to the recent and ongoing recovery from civil war in Angola. These are added to by statutory and traditional policy frameworks, the national endowment with natural capital (e.g. oil, uranium, diamonds, zinc) and the integration into global markets, which strongly affects national economies of both countries at large.Underlying land use decisions were found to be largely driven by individualized perspectives on growth ideologies, consumerism and wealth-aspirations connected to globalization processes. However, at present the result of these perspectives is still mainly a small-structured conversion to rainfed agriculture as a component of subsistence strategies of local livelihoods, and thus stands opposed to other regions of the world, where change processes are much more driven by large companies or follow national regulations and result in more intensive uses. 相似文献
4.
After independence, Zimbabwe adopted two major land reform programmes to address the racially skewed land ownership. Due to the perceived failure of these programmes, the country embarked on a highly politicised and forceful acquisition and re-distribution of white owned commercial farms under the Fast Track Land Reform Programme (FTLRP). Whereas a large number of Zimbabweans have been allocated land under the programme, there has been a significant decline in agricultural productivity and an increase in degradation of land and associated resources. Popular opinion has even suggested the country’s current socio-economic challenges are linked to the programme. Mitigating land degradation, enhancing agricultural productivity and promoting natural resources sustainability requires an objective understanding and determination landscape transformation within relevant administrative decision making spatial extents. In this study, we adopted multi-temporal remotely sensed imagery to determine landscape transformation after the implementation of the FTLRP in Chipinge administrative district, characterised by heterogeneous land usage and natural resources. Major land-use-land-cover types were determined using the Support Vector Machine classification algorithm and accuracy established using field survey and ancillary data. Results show significant landscape transformation after the implementation of the FTLRP. Specifically, there was a decline in plantations, small farms, water bodies and forests and an increase in bare areas and settlements. This study demonstrates the value of remotely data in monitoring landscape transformation arising from a shift in policy. Furthermore, these results provide an insight into multi-temporal spatial changes in cultivated, natural and degraded lands, valuable for designing measures to improve landscape productivity and to adopt relevant rehabilitation measures. Understanding multi-temporal landscape change within an administrative boundary is particularly valuable for area specific planning, policy formulation and adoption of desired mitigation measures. 相似文献
5.
Predicting soil erosion potential is important in watershed management. A rapidly growing Iranian population and climate change are expected to influence land use and soil sustainability. In recent years, northern Iran has experienced significant land use changes due to internal migration along the Caspian coast and conversion of forests and rangelands. Considering the effect of these changes in the future, the purpose of this study is to forecast land use patterns and investigate soil erosion scenarios using the Revised Universal Loss Equation and Markov Cellular Automata. Data from 1981 to 2011 were used as a baseline to estimate changes that might occur in 2030. The results reveal that the mean erosion potential will increase 45% from the estimated 104.52 t ha−1 year−1 in the baseline period. Moreover, the results indicate that land use change from forest area to settlements will be the most significant factor in erosion induced by land use change, showing the highest correlation among erosional factors. Projecting land use change and its effect on soil erosion indicate that conversion may be unsustainable if change occurs on land that is not suited to the use. The method predicts soil erosion under different scenarios and provides policymakers a basis for altering programs related to land use optimization and urban growth. Those results indicated the necessity of appropriate policies and regulations particularly for limiting land use changes and urban sprawl in areas of unfavorable soil erosion risk factors. 相似文献
6.
The novelty of this study lies in the analyses of legislation concerning land use policies by examining the specific boundary between land ownership and land take. The basic motive was that the European Commission (EC) withdrew the Soil Framework Directive (SFD) in 2014 following the objections of certain Member States (MS) who countered that as most lands are privately owned, they should not fall under the remit of public governance. Since the withdrawal of the SFD land take is an issue receiving more attention. The legal content of ownership rights has been subjected to constant debate in the context of land-use policies and planning practices, which raises the questions of who decides how the land can be used and whether administrative authorities give priority to non-agricultural uses. Our study seeks to explore these issues through the lens of property law by comparing different legislations on access to land on three levels of policy implementation: the EU, the national, and the local levels. MS legislations are highlighted through the example of Hungary in two aspects: (1) regulation regarding Access to Land and Land Ownership Rights (ALOR), and (2) legislation and results of the LANDSUPPORT decision support system concerning Land Take Changes (LTC). We designed figures to demonstrate how policymakers can use the new LANDSUPPORT platform to show the gaps and inconsistencies among the above aspects. We found that the legislative regulations concerning private land use to achieve soil protection objectives remain the weakest link in the environmental protection legislation of the EU. Anxieties concerning built-in legal guarantees on each of the studied levels actualise our research. Currently, global land management is not on the political table although common European legislation might be able to preserve land for agricultural use. 相似文献
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8.
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
9.
Exurban communities—a significant form of urban sprawl—can transform natural land cover. Exurban development refers to an expansion of communities located outside a city and its suburbs. One of the main reasons these settlements develop is a desire by residents to live closer to nature and developers’ recognition of the profitability of addressing this desire. Additionally, exurbs can become prosperous regions settled by people with high income. However, exurban development not only directly affects community patterns, but also species patterns, habitat reduction and disconnection, as well as land cover and land use alterations. The purpose of this paper is a quantitative analysis of the land cover transformation and forest fragmentation in Post-Soviet Russia, based on an empirical case study of the city of Kurgan. This case study also contributes to the overall research of urban sprawl in Russian provinces by adding to the discussion of homeowners’ behavior, regional environmental policies, and their role concerning the impacts of exurban settlements on the natural environment. This paper uses remote sensing imagery, census data, and primary data to analyze land cover change due to the emergence of exurban communities around Kurgan, Russia, with specific emphasis on the changes to native vegetation resulting from human behavior and stakeholder preferences. 相似文献
10.
Soil is a natural resource essential to human welfare by virtue of its numerous crucial functions. In the past, soil has been taken for granted because of its widespread, albeit finite, availability. However, now that world's population is projected to exceed ten billion before the end of this century, soil is increasingly perceived as a precious commodity. Consequently, soil is increasingly under pressure by rich private investors and governments within the poorest countries to satisfy appetites for food production and biofuel. A case study is used to explore the plausibility of soil being considered as ‘brown gold’. Based on the comparison of land use maps, we estimated the value in terms of resource from raw material, carbon sink and virtual calories of the productive soil lost during the period 2003–2008 in the Emilia-Romagna Plain, one of the most productive areas of Italy. More than fifteen thousand hectares of cropland underwent land use change – in particular urbanization – over the 6-year period with an implied loss of crop production potential equivalent to the daily calorific requirement of more than 440,000 people. Taking into account that Italy is no longer self-sufficient in food production, such a loss appears to be strategically significant. Perhaps more importantly, urbanization and soil sealing has had negative ramifications on environmental sustainability, on both local and broad scales, with increased consumption of public funds. A logical framework of the socio-economic impact of land use change has been compiled and is presented as a possible example of a policy relevant approach to managing productive soils as a finite resource. 相似文献
11.
Impact Assessment was introduced by the European Commission in 2002 in order to make policy development more transparent and improve the ‘quality’ of European policies. Cross-sectoral consultation, broad participation and the quantitative assessment of the impacts of policies are significant elements of this process. This article specifically addresses the role of tools modelling the impact of policies on land use in Impact Assessment. The choice of a specific modelling tool is conceptualised as an action situation interlinked with other action arenas. The article aims to uncover the institutions structuring the action situation. The outcome of the empirical work suggests that two types of Impact Assessments can be distinguished. Impact Assessments either substantively contribute to the specific policy that the Commission proposes or they legitimise policy choices ex post that have already been adopted. The legislative procedure that applies to a specific policy sector, the policy making culture in the DG and the stakes that are at issue seem to influence whether Impact Assessments contribute to policy development, or legitimise it. Furthermore, the article describes the situation in which desk officers choose a modelling tool throughout Impact Assessment. To advance their careers desk officers aim to produce policy proposals which respond to the issues raised by the actors involved in Impact Assessment and specifically in policy development and, later on, adoption. Therefore, desk officers’ preferences are shaped by the community that is involved in policy development and Impact Assessment. The article describes what role modelling tools play in European Impact Assessment procedures and it names the heuristic of criteria which desk officers use to choose a modelling tool. Besides several technical and data problems of modelling land use impact, it seems to be unlikely that land use will become a significant dimension of Impact Assessment and modelling as it is confronted with an unfavourable institutional environment at the European level. 相似文献
12.
Rapid land use change has taken place in many arid and semi-arid regions of China over the past decade, such as in Yellow River Basin. In this paper, changes in the land use pattern of the Yellow River Basin were analyzed using Landsat TM data in 1990, 1995 and 2000. The aim was to improve the understanding of changes in land use with a view to identifying potentially more sustainable systems of land use. Firstly, the mathematical methodology was explored and developed for spatial pattern changes of land use, which include the degree index model of land use dynamic, index model of land use degree, mean center model of land use and transformation model of land use. Based on these models, the changing spatial patterns of land use were calculated and analyzed. During the period 1990–2000, the areas of cropland, built-up land and unused land all increased, the area of cropland increased dramatically by 2917 km2, while the areas of grassland and woodland decreased by 4668 and 33 km2, respectively. Meanwhile, the spatial pattern of land use also experienced a great change. Then the driving factors of land use change were investigated, the governmental policies on eco-environmental protection, population growth and meteorological conditions were the major factors that caused the land use change in the past decade. 相似文献
13.
As a kind of activity to break down the original land ecosystem, land consolidation causes the ecosystem to undergo a process of “stability-unstable-stable”. The Chaohu Lake Basin is a typical traditional agricultural planting area and extensive implementation of large-scale land consolidation projects. By monitoring the impact of land consolidation activities in a specific time period in the basin on the project areas and surrounding environment, the spatial and temporal impacts of large-scale land consolidation on regional eco-environmental quality are analyzed. This study mainly monitors crop growth, soil moisture and temperature changes in the land consolidation project area, and the corresponding changes in the surrounding environment. The response of ecological environment factors caused by land consolidation can be embodied in indicators such as humidity, greenness, heat and dryness. Four indicators of NDVI, WET, LST, and NDBSI were selected, using principal component analysis, monitoring the environmental quality changes in the land consolidation areas of Chaohu Lake Basin. Result shows that the ecological environmental quality of the study area exhibits long-term convergence and short-term divergence, and the correlation between the ecological indicators is not significant. The average contribution rate of the first principal component eigenvalue is 67.94 %. The implementation period of the land consolidation project will seriously interfere with the ecological environment, but it can be restored within 3–5 years after implementation, and the ecological environmental quality of the project area will continue to improve. Land consolidation not only can improve the quality of the ecological environment in the consolidation area, but also can promote the surrounding environment. The findings provide theoretical basis and decision guidance for the improvement of land consolidation planning and design (reconstruction) in China, and offer suggestions on strategy-oriented support and scientific basis for promoting the long-term development of land consolidation worldwide. 相似文献
14.
土地利用/覆被变化动态监测是掌握土地资源数量、进行土地利用评价的重要依据。基于遥感和GIS技术提取金堂县2001、2007、2010和2013年4期土地利用变化信息,并应用模型对研究区土地利用时空变化进行分析。结果表明:(1)土地利用类型以耕地和林地为主,建设用地和林地的单一土地利用动态度为正,面积显著增加;耕地、草地、水体和其他的土地利用动态度为负,面积减少;综合土地利用动态度由6.12%增加到13.81%,土地利用变化强烈。(2)土地利用空间变化显著,土地利用空间变化主要发生在金堂县城、赵镇、三星镇和淮口镇等地;土地利用转化明显,耕地和建设用地的变化最强烈,建设用地、耕地和林地之间的相互转化尤其显著。(3)地形因子对土地利用变化具有较大影响,土地利用变化随高程、坡度的增加而减少,且表现较强的相关性,符合二次变化曲线的特征;阳坡较阴坡对土地利用变化的影响大。这一研究结果为区域土地利用评价提供重要依据,有利于实现土地利用的合理布局和调控管理,对区域土地资源的合理开发利用具有重要意义。 相似文献
15.
With rapid increases in global food demand and production, oil palm expansion constitutes a major emerging challenge for forest conservation in Amazonia and other tropical forest regions. This threat is evident in the Peruvian Amazon, where local and national incentives for oil palm cultivation along with growing large-scale investments translate into accelerated oil palm expansion. Environmental sustainability of oil palm cultivation in the Peruvian Amazon is contingent on policy incentives for expansion onto already-cleared lands instead of biodiverse, high carbon primary rainforests. Previous research indicates that while industrial plantations use less land area than local smallholders, companies have a higher tendency to expand into primary rainforests. However, the motivations behind these differing expansion scenarios remain unclear. In this study we combine data from optical and radar satellite sensors with training information, field discussions, and review of public documents to examine the policy incentives and spatial patterns associated with oil palm expansion by smallholders and industries in one of Peru’s most rapidly changing Amazonian landscapes: the Ucayali region of the city of Pucallpa. Based on our satellite-based land cover change analysis, we found that between 2010 and 2016, smallholders utilized 21,070 ha more land area for oil palm than industries but industrial expansion occurred predominantly in old growth forests (70%) in contrast to degraded lands for smallholders (56%). Our analysis of national policies related to oil palm expansion reveal policy loopholes associated with Peru’s “best land use” classification system that allow for standing forests to undergo large-scale agricultural development with little government oversight. We conclude that both sectors will need careful, real-time monitoring and government engagement to reduce old-growth forest loss and develop successful strategies for mitigating future environmental impacts of oil palm expansion. 相似文献
16.
Forest and pastureland soils in highland of northern Iran are being seriously degraded and destructed due to extensive agricultural activities. These land use changes are usually accompanied by decreasing in concentrations of soil organic carbon and nutrients and also deterioration of soil structure in these regions. However, studies on concentration of nutrients and carbohydrates in soils suggest that the location of nutrients within aggregates of each size should be determined. This study was to evaluate the nutrient elements and carbohydrate distributions within water-stable aggregates (WSA) of virgin forest and pasture lands under different land uses in Alborz maintain range, northern Iran. In September 2006, soil samples were collected from depths of 0–20 cm in Typic Haploxerolls soils. The overall pattern indicated that the mean weight diameter (MWD) and WSA were greater in the virgin pasture and forest soils compared with the adjacent cultivated (ex-forest and ex-pasture) soils and aggregates of >1.0 mm size were dominant in the virgin soils, whereas the cultivated soils comprised aggregates of the size ≤0.5 mm. Distribution of organic carbon, nitrogen, phosphorus and carbohydrates within the WSA showed preferential enrichment of these parameters in the macroaggregate fraction (4.75–1.0 mm) for the virgin soils and microaggregate fraction (>0.25 mm) for the exposed soils. Cultivation decreased the concentration of carbohydrates by 23.6% and 20.6% in ex-forest and ex-pasture lands, respectively. Average distribution of total exchangeable bases within WSA showed that the cultivation of forest and pasture soils significantly led to reduce in these nutrient in the 4.75–2.0 mm fraction and increase in concentration of these exchangeable cations in <0.25 mm fractions. In general, results indicated that cultivation significantly led to 71% and 6% reductions in total exchangeable bases within the 4.75–2.0 and <0.25 mm aggregate fraction, respectively, for virgin soil. Since smaller aggregates are preferentially removed by erosion, this study emphasizes the need for sustainable soil management practices that they will minimize nutrient loss when forest or pastures lands are converted to croplands. 相似文献
17.
In Latin America countries, competition for access to natural resources among different groups has been a major reason for the outburst of violence over the last decades. One of the main aims of the political ecology concerns the understanding of the environmental conditions that can underlies the social conflict among people. Such understanding needs to be based on a detailed investigation of the natural resources of the landscape, mainly the soils. Few years ago the Italian Ministry for Foreign Affairs financed a soil survey with a humanitarian purpose: the development of a peace plan between Peru and Ecuador by improving the socio-economic conditions of the rural populations living in the areas close to the border. To achieve such goal, the construction of an irrigation canal was planned to irrigate few hundred hectares in the province of Ayabaca, on the border between Peru and Ecuador. To be soundly planned and designed, the canal project was obviously based on a preliminary soil survey that is essential to assess the irrigation suitability of the land. In this work, the authors illustrate the soil characteristics within the study area, their suitability for irrigation and the key aspects for future land uses, highlighting the philosophy followed in applying the land evaluation system which took into consideration the social, cultural and humanitarian purposes of the soil survey. Results proved the feasibility of the financed project and the potential increase of the living conditions of the rural people. 相似文献
18.
The Special Issue (SI) “Environmental Risk Mitigation for Sustainable Land Use Development” presents seventeen interrelated papers addressing the key concept of environmental risk mitigation and sustainable land use development. The issue argues that risk mitigation depends directly on the risk assessment analysis and the quality of applied measures. Therefore, the more precise are risk assessment conclusions, the better the risk mitigation measures would be. This collection of papers follows the vision of the Sendai Framework for Disaster Risk Reduction 2015–2030 (Sendai Framework) which states that the integration of sustainable development objectives into disaster risk mitigation and adaptation at all levels and at all stages of policy action are of paramount importance for the sustainability of our communities. The final purpose of the issue is to address the mutual roles of land use policy on environmental risk mitigation and adaptation, especially disaster risks. 相似文献
19.
Building on the contributions of Mather and others, this paper offers an approach for developing a more comprehensive theory of the forest transition. We argue that long-run changes in forest cover in a country or region cannot be separated from the overall pattern of land use changes. Moreover, this pattern is determined by relative land values; forest cover changes over time as the value of one land use relative to the value of its competing use changes over time. However, the actual values that are used to allocate land may be far from optimal; that is, the presence of market, policy and institutional failures can distort economic and political incentives that can lead to bias in favour of one type of land use over the other, and may ultimately explain why a forest transition may be delayed unnecessarily in some countries and regions. 相似文献
20.
Soil vulnerability and environmental land use conflicts were quantified and cross tabulated in the Sordo River basin (Trás-os-Montes Province, NE Portugal) to provide insights about the risk of soil degradation within that basin. Soil vulnerability was assessed by algorithms of multi criteria analysis and weighted linear combination, whereas environmental land use conflicts were described by an original approach. Three vulnerability scenarios were considered, enhancing the importance of topographic slope, soil class and use and occupation of soils, respectively, as vulnerability factors. Regardless the scenario, approximately two-thirds to the basin was defined as areas with high vulnerability. Fortunately, only 10.9% of the basin is in environmental conflict, where actual land uses deviate from natural uses determined by soil characteristics. The cross tabulation of high vulnerability areas with conflict areas, which defines the areas at risk of soil degradation, reveal that risk areas account for approximately 3.2–8.4% of the basin, depending on the scenario, being concentrated in steep slope hillsides suited for forest or mixed forest and pasture occupations but actually used for irrigated crop lands, vineyards and olive yards. Some conservation practices are implemented in the vineyard and olive yard areas, namely through the construction of terraces. These structures minimize soil erosion but are potentially unstable beyond given intervals of terrain slope. On the other hand, the maintenance of terraces is costly and for that reason eventually unaffordable for many farmers, and they also entail a mischaracterization of the historical and architectural heritage of the Douro Wine Region (UNESCO World Heritage). In this context, it was suggested the approval of legislation as regards the design, construction and maintenance of terraces, while in a broader perspective it was recommended the appreciation of a European Directive for soil protection and its subsequent transposition to the national legislation. 相似文献