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131.
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   
132.
133.
This paper evaluates the role of trade liberalization and agricultural intensification in mitigating climate change cause and effects on land use and emissions using a computable general equilibrium model. Our results indicate that cropland expansion triggered by climate-induced crop productivity changes results in deforestation and increases emissions in South Asia and globally. Global full trade liberalization on all goods is the optimum policy for South Asia despite significant global deforestation, but for the world, unilateral partial trade liberalization on all goods is a more appropriate policy while ensuring a considerable emissions reduction for South Asia. These results indicate that mitigation responses to climate change are location specific and no one trade policy is suitable at the regional and global levels. Lastly, agricultural intensification by improving productivity growth is the best strategy in land-based emissions mitigation, thereby avoiding the transformation of forest and pasture lands for agricultural cultivation both at regional and global levels.  相似文献   
134.
Over the past centuries, land systems in Italy experienced fundamental shifts, owing to the availability of new energy forms, population surges, and technological progress. The 20th century was characterized by massive productivity increases, accompanied by gradual land abandonment and the return of forest land. We here analyze 120 years of land system change in Italy, applying the human appropriation of net primary production (HANPP) framework, a metric for socio-economic pressures on terrestrial ecosystems. HANPP allows integrating ecological with societal perspectives, by systematically quantifying (a) biomass harvest and (b) the difference between potential productivity of ecosystems and current productivity induced by land use processes, such as land conversion, or land degradation. Besides assessing national trends we calculated HANPP separately for the Italian North and South between 1934 and 2007, in order to scrutinize if high regional discrepancies in terms of natural and socio-economic preconditions translate into diverging land system trajectories. Our results show that national HANPP has been declining from 78% of natural productivity before WWII to 56% in 2007, indicating a declining land -use induced pressure on biomass flows over time. Simultaneously, biomass harvest increased by around 26% due to agricultural intensification, despite shrinking croplands. Although we found a significant difference between the Northern and Southern region in the absolute levels of several land use indicators related to biomass appropriation, the overarching trends of land system change were remarkably similar in both regions. This suggests that underlying drivers of land system change, such as policies aimed at land-use intensification and structural change were equally dominating land system trajectories in the North and South of Italy, not withstanding their socio-ecological divergences.  相似文献   
135.
涂曼妮 《价值工程》2014,(3):212-213
长期以来,高职院校思想政治理论课教学一直面临一种尴尬的境地:一方面,学生对课程本身存在偏见和抵触,另一方面,课堂以教师为主体,学生被动地听,这种教学忽视了学生的自主学习和探究,使学生缺少独立思考的时间和空间,因而教学效果差。而情景教学法能较好地激发学生学习兴趣、发挥其主体性,因此,情景教学法成为职教院校思想政治课教学方法改革的重要内容之一。本文结合教学实践,从教学内容,教学开展方式等方面阐述了情景教学法在高职思政课教学中的应用。  相似文献   
136.
In the search for solutions to complex real-world problems, the benefits of transdisciplinary research (TDR) have been widely heralded. Land use science appears to be a designated field for TDR. However, to date, the additional expenses of TDR are accompanied by a so far not proved added value, and empirical findings are claimed to be scarce and dispersed over several disciplines and case studies.We reviewed 299 articles obtained from a structured literature search to (1) investigate the current differences between theory and practice, (2) identify empirical findings, and (3) ascertain the contributions of TDR to promoting sustainable land use management.Our results demonstrate that, in spite of an increasing conceptual consistency in the theoretical discussion of TDR, the implementation of TDR remains a substantial challenge, in part because of the gap between theory and practice. In addition, research on TDR is science and process centred. The benefits of TDR in addressing real-world problems within the field of land use remain unproven.  相似文献   
137.
Landscapes provide an array of services to society, from the provision of food and material, to the provision of cultural ecosystem services such as recreation, aesthetics or spirituality. Studies on cultural ecosystem services, however, remain rare and little is known about the spatial localisation of these services. In this study, we adopt and test a framework to identify and map the provision of cultural ecosystem services as perceived by tourists in an Alpine region, i.e. the region of South Tyrol in Italy. A photo-based questionnaire survey is combined with cartographical representations of landscape types to elicit hot and coldspot areas of cultural ecosystem service provision. We statistically test for influences of the land use type and the respondents' socio-demographic background on the tourists' perception of these services. The results show that different spatial patterns emerge for each of the investigated cultural ecosystem services depending on the distribution and extent of the landscape types to which they are related. In particular traditionally managed landscapes, small in extent and mainly scattered over large areas between 1000 and 2200 m a.s.l., are hotspot areas of aesthetic beauty, leisure activities and spirituality. In contrast, intensively managed landscapes, mainly located in the lowland plains of the study site, are considered to be more important for the provision of cultural heritage values. While the results suggest that land use type exerts the strongest influence upon tourists' perception, factors such as the respondents' perceived importance of the services, their gender, cultural background, environmental engagement and experience with the landscape play a significant but subordinate role. We conclude that the spatially explicit information about the provision of cultural ecosystem services can serve as a helpful basis for the design and further implementation of land use policies that acknowledge the high touristic value of traditionally used landscapes in mountain regions.  相似文献   
138.
Mass tourism, which has traditionally been associated with an unsustainable use of natural resources and intensive land use, is frequently identified as a major environmental stressor in coastal regions. Nonetheless, mass tourism resorts typically have a compact and vertical urban configuration and have been shown to make more efficient use of water resources than other low-density tourist destinations. This article investigates how the main variables identified by the literature as determinants of water consumption by hotels influences water efficiency in hotels in Lloret de Mar, a well-known mass tourism destination on the Costa Brava in Spain. The results of a generalized linear mixed model show that large, high-rise hotels that attract thousands of tourists annually also benefit from economies of scale in terms of water efficiency.  相似文献   
139.
The assessment of land use plan implementation is a contentious issue. The debate centers on whether the crucial evaluation element is conformance of development to plan directives or alternatively, plan performance, i.e. the degree to which the plan is actually used. An analytic framework combining both conformance and performance in the evaluation of (regional) land use plans is applied to the case of the Central District Plan in Israel. Qualitative and quantitative simulation methods are exploited. Qualitative analysis reveals that both performance and conformance are greater than indicated by non-contextualized, numeric evaluations. Additionally, high conformance does not necessarily imply good plan performance. Quantitative simulation suggests that plan performance with respect to land values and densities is initially pronounced as expectations for development are subdued but subsequently tends to wane merging with the counterfactual trend. Findings imply that plan assessment needs to consider the transaction costs of land use re-designation and actors’ perceptions of the probability that plan amendments will be approved. These perceptions differ across actors as a function of the political influence that they wield.  相似文献   
140.
The accelerated rural hollowing driven by vast and increasing out-migration of rural labors under urban–rural dual-track system has imposed huge obstacles on improving land use efficiency and coordinating urban–rural development in China. Taking Dancheng County in Henan Province as an example, this paper analyzes the status quo of rural hollowing and discusses two typical rural residential land consolidation and allocation (RRLCA) practices in traditional agricultural areas (TAAs) of China. The results show that, Dancheng experienced rapid rural hollowing characterized as the hollowing of rural industries, infrastructure, and residential population and settlements. However, Dancheng has considerable potential and the necessity of RRLCA, for the model-based estimation shows that the potential of increasing farmland by carrying out RRLCA was about 5649 ha. The two community-based RRLCA practices show positive effects on the improvement of local living conditions, increment of farmland area and development of rural industries. Their experiences, including self-organized rural planning, democratic decision-making, and endogenous institutional innovation may benefit future RRLCA. Overall, it indicates that promoting community-based RRLCA scientifically according to local conditions could provide an integrated platform for increasing farmland area, developing modern agriculture, promoting new countryside construction, and thus revitalize hollowed villages. On considering the limitations and obstacles of current initiatives, suggestions for future RRLCA in rural China have been put forward.  相似文献   
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