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81.
Suppose we are given a cake represented by the unit interval to be divided among agents evaluating the pieces of the cake by nonatomic probability measures. It is known that we can divide the unit interval into contiguous and connected pieces and assign them to the agents in such a way that the values of the pieces are equal according to the individual agents measures. Such division is said to be equitable and simple. In this paper we show that an equitable and simple division also exists in the case of dividing two-dimensional cake represented by the unit square. In this case, by simple division we mean dividing the unit square firstly by horizontal cuts, and then partition the resulting rectangles by vertical cuts. We give a method of obtaining a proportional and simple division of this cake. Furthermore, we prove the existence of proportional, equitable and simple division.  相似文献   
82.
文章运用产业上游度测度模型,测度了我国住宿和餐饮业在产业链上位置,考察了其在产业链上位置的动态变迁。总体来讲,住宿和餐饮业在全球产业链上和国内产业链上的位置都向产业链上游移动。从封闭经济到开放经济,住宿和餐饮业的产业上游度存在着较大波动,2002—2010年全球产业上游度都大于其国内产业上游度;2012—2017年则相反,住宿和餐饮业国内产业上游度波动幅度要大于其全球产业上游度波动幅度。住宿和餐饮业净出口变化方向与其国外产业上游度变化方向基本相同,净出口增加对其国外产业上游度上升有促进作用。住宿和餐饮业全球产业上游度变化趋势与其国内产业上游度变化趋势基本相似。总体来讲,现阶段住宿和餐饮业国内产业上游度增长速度要大于其全球产业上游度增长速度。  相似文献   
83.
Farmland abandonment and the decline of livestock activity in the Mediterranean mountains have resulted in dramatic landscape changes, including the generalized expansion of shrublands and forests, and the homogenization of the old cultural landscapes. This process has a variety of consequences from ecological, geomorphological and hydrological points of view, as well as from the perspectives of land management and public awareness. An intense debate currently surrounds the discussion and evaluation of rewilding (the process of passively allowing woody encroachment, as well as the reintroduction of large mammals) as an opportunity for enhancing biodiversity and restoring original landscapes after centuries of human activity versus ecological restoration (activities leading to the recovery of degraded ecosystems, including clearing and light human activity). There is no clear consensus regarding the best way to improve the ecological relationships and functioning within an ecosystem. Biodiversity and sustainability can be seen under different levels of human pressure and landscape transformation; total farmland abandonment is not always the best alternative, particularly when local inhabitants aim to sustain themselves using local resources. Many geographers and ecologists consider that extensive stockbreeding in a partially open landscape is a rational way to (i) improve landscape organization, (ii) increase flows and turnover within the ecosystems, (iii) increase the diversity of plants and animals that benefit from a relatively light human presence, and (iv) reduce wildfire risk. However, it has proven challenging for land managers and stockbreeders to clear the best old abandoned fields and “construct” a sustainable, balanced landscape that combines forests, shrublands and open lands. Private landowner involvement and support from the general public is crucial for both funding and the long-term maintenance of benefits. The best old fields should be cleared in the context of high-resolution knowledge of the topography, grassland characteristics, grassland cycles and livestock management. Such efforts are likely to be an excellent opportunity to introduce compatibility between light human activity and increases in biodiversity and sustainability for many marginal mountains, where land abandonment and general forest/shrub recovery are the inevitable tendencies. This paper examines some of the contrasting positions of the scientific community regarding the rewilding or ecological restoration of mountain landscapes, and briefly highlights some experiences in which intentional clearing of old abandoned fields has benefited stockbreeding, biodiversity, runoff generation and wildfire risks. Notably, we describe a sub-Mediterranean valley of the Iberian Range, Northern Spain, as an example. In the long term, we find that the intentional clearing of the best old fields allows the slow organization of a final landscape that will be more useful for local inhabitants, thereby helping to reverse human depopulation in these regions.  相似文献   
84.
Drought is a complex natural hazard with social and environmental implications. Satellite information is increasingly used to support decision-makers in preventing or coping with the negative impacts of drought. The integration of local and scientific knowledge to support drought monitoring is still far from being the main procedure in the development of drought monitoring and early warning systems. This study aimed at assessing the degree of convergence between satellite information on the effect of droughts on rangeland vegetation, from time series analysis, and farmers’ perception of drought in North-West Patagonia, Argentina. We characterised the scientific evidence of drought in terms of duration, spatial distribution, most severe years and recovery for the period 2000–2018 by identifying inter-annual NDVI changes. Farmers’ perceptions and experiences of drought were studied with open-ending interviews, with respect to occurrence, duration and recovery for that period. Satellite information matched farmers’ perception of drought at a regional scale, emphasising the value of remote sensing tools in supporting regional policy decision-making. However, farmers’ perceptions and recall of past drought impacts were more diverse than satellite information at a local level, highlighting the need for knowledge integration at finer scales.  相似文献   
85.
Bioeconomy comprises a novel approach towards economic development in the European Union (EU). Its development should be confined by the planetary boundaries (biocapacity). We integrate the land footprint approach related to production and land biocapacity to assess the trends in capacity and productivity of bioeconomy in the EU countries throughout 1997–2013. Results show that the level of production-based land footprint and land biocapacity vary across the EU countries. However, Belgium is the sole case where production-based land footprint exceeds land biocapacity. The highest possibilities for development of the bioeconomy sector are observed for Slovenia, Croatia, Romania and Slovakia. Meanwhile, Estonia, Denmark and the United Kingdom have almost achieved the level of land biocapacity. Considering the catch up growth rate, almost all of the EU countries (with exception of Greece, France, Italy and Romania) show increasing footprint-to-biocapacity ratios with the highest values for Estonia and Latvia. The significant absolute decoupling between production-based land footprint and agricultural value added is observed in Denmark. Meanwhile, Italy, Lithuania and Spain show relative decoupling. Thus, these countries should pay particular attention to productivity improvements in forestry and agriculture. This study contributes to setting the targets for bioeconomy policy that can support the sustainable and efficient use of biological resources.  相似文献   
86.
To combat the critical stresses of rising urbanization, the government acquires land from private owners using the power of eminent domain. This land assembly causes negative externalities such as increasing social tension and injustice that may impose a long-term threat to stability and sustainable development. Therefore, there is a need to make the land acquisition process more transparent and just. Considering the unique Indian context where informality has a strong presence, we propose an approach based on game theory that models the bargain through a three-stage Nash equilibrium game. Four agents – the government, the private developer, the landowner, and the free rider – are considered. We provide conditional solutions for the generalizable Case and proceed to model different stakeholder behavior patterns through two utility functional forms – linear and exponential. In the linear case, we find that the free rider obtains half of the revenue of the project, whereas the landowner gains between one-fourth and one-half of the revenue. Thus, we highlight the undeniably crucial role free riders play in land acquisition negotiations. However, closed form solutions cannot be obtained for the exponential form, due to which we use simulations to demonstrate a solution procedure. We conclude by stating that the proposed model can be useful in formulating future land policies in a sustainable and inclusive manner, with optimal utility derivations for all concerned stakeholders. Our model can also be extended to other spatial contexts where informality features heavily in the land market, especially in the Global South.  相似文献   
87.
Aside from the very high inequality of land ownership, South Africa is characterised by a dual land tenure system comprising of private ownership and communal land ownership. Using waves 4 and 5 of the National Income Dynamics Study longitudinal data set, a set of econometric methodologies is employed to quantify the impact of ownership and tenure on an index of subjective wellbeing (SWB) constructed from eight self-reported responses covering general life satisfaction, contrast, social capital, mental health and hope for future. Controlling for the income effect and other pertinent drivers of SWB, the study highlights the non-income impact of land ownership and tenure on the subjective wellbeing of individuals. To account for possible endogeneity and self-selection, instrumental variable and matching method-based treatment effects are computed. This paper has two main findings in relation to land tenure in South Africa: (a) land owners have on average a higher index of SWB compared to those not owning land, and (b) owning land privately, compared to owning land communally, has a positive impact on subjective wellbeing within land owners. These results are consistent and statistically significant across the various estimation strategies and provide additional motivation for expediting land reforms in South Africa.  相似文献   
88.
In recent decades the intensification of agricultural production in many European countries has been one of the key components of land-use change. The impact of agricultural intensification varies according to national and local contexts and a greater understanding of the drivers of intensification will help to mitigate against its negative impacts and harness potential benefits. This paper analyses changes in land use intensity in six case studies in Europe. A total of 437 landowners were interviewed and their responses were analysed in relation to changes in land use intensity and agricultural production between 2001 and 2011. In the case studies in Western and Eastern Europe we observed stabilisation during the last decade, and no clear tendency of increase or decrease of land use intensity. The use of fertilizers and pesticides seems to have decreased in our cases in Western Europe, which is contrary to trends in Eastern Europe. Agricultural production remained stable in almost all cases, except for an increase in Austria and Romania which may indicate that the farming efficiency has increased. A statistical analysis showed a division between study areas in Romania and Austria (increasing land use intensity) versus those in the Netherlands, Denmark and Greece (decreasing). In the Mediterranean cases we observe a process where agriculture is becoming increasingly marginalised, at the same time as changes in function with regard to urbanisation and recreational land uses have taken place. Logistic regression highlighted the importance of farm size and farmer type in understanding changes in land use intensity. The dominant pattern of stabilisation which has occurred over the past 10 years may also partly be a result of effective EU and national environmental and agricultural policies, which are increasingly concerned with improving environmental conditions in rural areas.  相似文献   
89.
A vast array of trends and innovations, such as drones and person-to-person trust solutions, have been proposed to revolutionize the task of recording land and property rights. There is, however, a gap in current research regarding how to approach systematically the future(s) of cadastral systems. This paper introduces socio-technical transitions theory and multi-level perspective (MLP) framework in particular as a way to structure potential pathways for cadastral systems. The approach emphasizes the role of institutional rules of the game – the regulative, normative and cognitive institutional elements – in socio-technical transition processes. Using the Finnish cadastral system as a case study, we illustrate the approach by forming three alternative transition pathways: (1) a cadastral system under digital transformation, (2) differentiating urban and rural cadastral systems, and (3) a cadastral system facing new data management challenges. After describing each transition pathway with a narrative storyline, we reflect them in light of previous discourses of the cadastral domain. Thereby, the study provides new insights into discussions about the future of cadastral systems and land administration in general.  相似文献   
90.
The main aim of this paper is to investigate the transformations of the Romanian agricultural paradigm under the domestic economic policy reforms. An econometric approach is adopted by analyzing the evolution of Romanian agriculture between 1960 and 2011 from the perspective of its implications on residential land economy. This methodological choice relies on its high degree of applicability and its ability to reveal the massive transformation of the Romanian agricultural paradigm during the period under focus. Two regression models have been developed in the attempt to analyze the evolution of total value added and labor productivity in agriculture. The results obtained during the research confirm that Romanian agriculture exhibits determinant and significant elements able to trigger a massive change of paradigm.  相似文献   
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