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41.
In the face of climate change and other environmental challenges, an increasing number of cities are turning to land design to enhance urban sustainability. Land system architecture (LSA)—which examines the role of size, shape, distribution, and connectivity of land units in relation to the system’s social-environmental dynamics—can be a useful perspective for examining how land contributes to the social and environmental aspects of urban sustainability. There are two gaps, however, that prevent LSA from fully contributing to urban sustainability dialogues. First, it is not well understood how urban design goals, as expressed by urban planners and other practitioners, relate to LSA and environmental outcomes. Second, most LSA work focuses on individual environmental outcomes, such as the urban heat island effect, instead of considering the broader suite of outcomes that LSA changes impact. Here, we undertake an integrated assessment of LSA impacts on surface urban heat island (based on land surface temperature), vegetation presence/health (based on NDVI), and bird biota at two riparian sites with different design intentions in the Phoenix, Arizona metropolitan area. The Rio Salado in Tempe underwent a city-led, infill redevelopment that mixed economic, recreational, and flood control design goals. The New River in Peoria experienced a more typical developer-driven urbanization. The contexts and design goals of the sites generated differences in their LSA, but only a few of these differences were sufficiently unique to contribute to divergent environmental outcomes. These differences reside in (1) the greater distribution of recreational land-covers and (2) increased surface water at the Rio Salado site compared to the New River site. Both changes are linked to land-cover patches becoming greener and cooler as well as a greater presence of waterbird and warbler species at the Rio Salado site. The distinctions between the sites provide insight for crafting design goals for redeveloping or restoring urban riparian landscapes in the Phoenix metropolitan area that are grounded in LSA. With the incorporation of additional relevant variables, especially socioeconomic ones, the research approach employed in this study provides a foundation for the assessment of other urban land system change.  相似文献   
42.
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   
43.
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   
44.
Large-scale land acquisitions (LSLAs) are increasing in Ghana amid a weak legal and regulatory framework. This paper explores the impacts of this phenomenon on farmer innovations under recurrent environmental changes. Using a case study of z, an indigenous innovative farming practice, the paper makes two interrelated arguments. Firstly, it shows that the pervasive enclosures coerced by the Ghanaian state undermine how indigenous knowledge could be proactively deployed for climate risk management. Secondly, LSLAs produce a social barrier to climate change adaptation, as they lead to heightened uncertainty and apprehension among farmers, which affects decisions on climate risk management. More specifically, land expropriation is an example of how adaptation could be hindered by governance, institutions, and policy at the extra-local scale, including not only existing land use laws, but also the constitutional guarantee of private property. The evidence supporting these arguments come from survey data on 619 plots, 70 in-depth interviews, village-level transect walks, and participant observations. Overall, the paper contributes to emerging debates at the interface of land use policy, climate justice, and sustainable adaptation. Theoretically, it also contributes to understanding State-society relations, as well as the political economy of eminent domain, often justified through discourses of “public benefits.”  相似文献   
45.
The Republic of Ireland possesses a land market that is constrained by minimal sales each year, less than 1%. In an effort to capitalise on milk quota abolition and to increase dairy production, a suite of tax incentives has recently been introduced in the Republic of Ireland to encourage land mobility and long-term leasing among Irish dairy farmers. Using Irish Farm Accountancy Database Network (FADN) data from 2011–2017 to examine this, a Heckman sample selection model explores two aspects; (i) the factors that influence a farmer’s decision to rent, or continue renting, land and (ii) the profitability of dairy farmers renting in land. We find self-selection into the rental market is driven by farm traits that include a high level of hired labour, the presence of a successor, intensive farming practices and dairy discussion group membership. The results show that rental agreements assist farms in achieving economies of scale. The findings provide evidence to support government intervention such as tax incentives for renting out land and knowledge sharing discussion groups.  相似文献   
46.
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   
47.
The sustainability of smallholder agriculture in the drylands of West Africa is a topic of long-lasting concern. This paper is focused on the scientific assessment of nutrient (mis)management affecting the long-term productivity of cropland. “Nutrient mining” is seen as a major mechanism for land degradation in the region. Two models will be the focus: that tied to the rangeland-to-cropland metric and the nutrient balance model. These tools of assessment follow a long history of environmental assessment and modeling that purposefully abstracts from the heterogeneity of the same farming practices that modeling efforts seek to assess. Abstraction is always part of modeling but the form of abstraction described here ignores any detailed understanding of farming practices and in so doing, demands very little information about farming practices. In this way, models serve as both the symptom and cause of continued ignorance of farming practices by most agronomists and soil scientists working in the region. The variables used in these models will be described and how these same variables are strongly influenced by the variation of farmers’ practices will be discussed. In addition, it will be shown that needless model abstraction results in research outcomes that provide very little insights to guide land policy formulation and agricultural extension. In short, these models point to the ultimate resource limits of the regional agricultural system but provide few insights of what could be changed to reduce rates of land degradation. The paper concludes by presenting alternative approaches that through their engagement with the diverse positionalities of farmers, provides insights useful for the development of effective land policies.  相似文献   
48.
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   
49.
This paper analyzes a dynamic stochastic equilibrium model of an asset market based on behavioral and evolutionary principles. The core of the model is a non-traditional game-theoretic framework combining elements of stochastic dynamic games and evolutionary game theory. Its key characteristic feature is that it relies only on objectively observable market data and does not use hidden individual agents’ characteristics (such as their utilities and beliefs). A central goal of the study is to identify an investment strategy that allows an investor to survive in the market selection process, i.e., to keep with probability one a strictly positive, bounded away from zero share of market wealth over an infinite time horizon, irrespective of the strategies used by the other players. The main results show that under very general assumptions, such a strategy exists, is asymptotically unique and easily computable.  相似文献   
50.
论文对区块链技术的发展阶段与区块链金融的监管必要性进行了简要分析和阐述,并结合区块链金融风险内容,提出了构建我国区块链金融监管模式的有效途径,以期推动我国区块链金融长久稳定发展。  相似文献   
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