844 resultados para scarcity


Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In public utilities, under supply constraints, fairness considerations lead to a market failure. This paper characterizes a two-period principal-agent contract for demand management, that mitigates this market failure in urban water systems. The contract is designed as an extensive form mechanism using subgame perfect Nash equilibrium (SPNE) as the solution concept. The contract is fair; and is shown to be economically efficient if, in case of deviation by the agent, the gain to the agent and the loss to the principal are small. It is shown that the assumption can be avoided in an infinite horizon contract.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Seeds are traditionally considered as common or even public goods, their traits as ‘products of nature’. They are also essential to biodiversity, food security and food sovereignty. However, a suite of techno-legal interventions has legislated the enclosure of seeds: seed patents, plant variety protections, and stewardship agreements. These instruments create and protect private proprietary interests over plant material and point to the interface between seeds, capitalism, and law. In the following article, we consider the latest innovations, the bulk of which have been directed toward genetically disabling the reproductive capacities of seeds (terminator technology) or tying these capacities to outputs (‘round-up necessary’). In both instances, scarcity moves from artificial to real.
For the agro-industrial complex, the innovations are perfectly rational as they can simultaneously control supply and demand. For those outside the complex, however, the consequences are potentially ruinous. The practices of seed-saving and exchange no longer are feasible, even covertly. Contemporary genetic controls have upped the ante, by either disabling the reproductive capacity of seeds or, through cross-pollination and outcrossing, facilitating the autonomous spread of the genetic modifications that are importantly still traceable, identifiable and therefore capable of legal protection. In both instances, genuine scarcity becomes the new standard as private interests dominate what was a public sphere.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tese de doutoramento, Biologia (Biologia Marinha e Aquacultura), Universidade de Lisboa, Faculdade de Ciências, 2015

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis explores the processes through which scarcity is constructed in informal settlements and how conditions emerging within its limits gives way to particular socio-spatial phenomena and influence the emergence of self-organisation and creative strategies from a non-expert perspective. At the same time, this thesis deconstructs these emerging tactics (reactive and transformative) in a diagrammatic way to generate a critical study of their potential for socio-spatial change that goes beyond the everyday survival. Most people associate scarcity with “not having enough” of something, most usually of a material nature. In contrast, this paper is based on the premise that scarcity is a constructed condition, therefore exploring it beyond its immediate manifestation and illustrating its discursive, distributive and socio-material components. In this line, the research uses Assemblage Theory as both an approach and a tool for analysis. This approach allows the research to depart from everyday narratives of the residents, and gradually evolve into a multi-scalar, non-linear reading of scarcity, by following leads into different realms and unpacking a series of routine events to uncover their connections to wider processes and particular elements affecting the settlement and the city as a whole. For this purpose, the research is based on a qualitative, flexible and multi-sited methodology, using different case studies as testing grounds. Collected data stems from a 11-months ethnographic fieldwork in informal settlements in Ecuador and Kenya, analysing the socio-spatial practices and strategies deployed by the different actors producing the built environment and arising from everyday and latent experiences of scarcity. The thesis examines the multi-scalar nature of these strategies, including self-building and management tactics, the mobilisation of grassroots organisations, the innovative ways of collaborating deployed by different coalitions and the reformulation of urban development policies. As outcomes of the research, the thesis will show illustrative diagrams that allow a better understanding of, firstly, the construction of scarcity in the built environment beyond its immediate manifestation and secondly, the way that emerging tactics a) improve existing conditions of scarcity, b) reinforce the status quo or c) contribute to the worsening of the original condition. Therefore, this thesis aims to offer lessons with both practical and theoretical considerations, by firstly, giving an insight into the complexity and transcalar nature of the construction of scarcity in informal settlements; secondly, by illustrating how acute conditions related to scarcity gives birth to a plethora of particular phenomena shaping the territory, social relationships and processes; and thirdly, by identifying specific characteristics within the informal that might allow for new readings of the city and possibilities for socio-spatial change under conditions of scarcity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Livestock keeping is increasingly becoming more popular in Kampala, the capital city of Uganda. However, lack of feed is a real challenge. Inadequate feed supply in urban areas is due to many interacting factors, which include among others land shortage, high cost of feeds, climate risks and poor quality of feeds. The objective of this study was to identify and examine the effectiveness of the strategies adopted by livestock farmers in urban and peri-urban areas of Kampala, Uganda to cope with feed scarcity. A total of 120 livestock farmers from Kampala were interviewed using a structured questionnaire. Dairy cattle (48.3%) and chickens (37.5%) were the most common species, followed by pigs (34.2%), goats (26.7%) and sheep (3.3%). Farm size was generally small both in terms of herd size and total landholding. Cattle and pig farmers in urban and peri-urban areas of Kampala ranked feed scarcity as their first major constraint, while chicken farmers had high cost of feeds. These farmers have adopted several strategies for coping with feed scarcity. Among the major coping strategies adopted were: changing of feed resources based on availability and cost (37.5%), purchasing of feed ingredients in bulk (29.7%), using crop/food wastes (26.6%), harvesting of forages growing naturally in open access lands (23.4%) and reducing herd size (17.2%). However, most of the coping strategies adopted were largely aimed at dealing with the perennial challenge of feed scarcity on a day-by-day basis rather than dealing with it using sustainable and long-term strategies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Formal statutory guidance to arbitrators involved in settling disputes over rents for agricultural holdings is contained in the Agricultural Holdings Act 1986. The particular features of the agricultural letting market raise valuation problems which the Act itself has failed to satisfactorily address, most notably the degree to which marriage value and scarcity should be taken into account. The 1995 Court of Appeal case of Childers v Anker addresses several of the key issues. This paper seeks to explore the findings and practical implications of the case for rental valuers and arbitrators. It argues that sitting tenants may be seriously disadvantaged by the court's judgements, not least by having to pay rents on review which reflect elements of marriage value and possibly scarcity value.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents a global scale assessment of the impact of climate change on water scarcity. Patterns of climate change from 21 Global Climate Models (GCMs) under four SRES scenarios are applied to a global hydrological model to estimate water resources across 1339 watersheds. The Water Crowding Index (WCI) and the Water Stress Index (WSI) are used to calculate exposure to increases and decreases in global water scarcity due to climate change. 1.6 (WCI) and 2.4 (WSI) billion people are estimated to be currently living within watersheds exposed to water scarcity. Using the WCI, by 2050 under the A1B scenario, 0.5 to 3.1 billion people are exposed to an increase in water scarcity due to climate change (range across 21 GCMs). This represents a higher upper-estimate than previous assessments because scenarios are constructed from a wider range of GCMs. A substantial proportion of the uncertainty in the global-scale effect of climate change on water scarcity is due to uncertainty in the estimates for South Asia and East Asia. Sensitivity to the WCI and WSI thresholds that define water scarcity can be comparable to the sensitivity to climate change pattern. More of the world will see an increase in exposure to water scarcity than a decrease due to climate change but this is not consistent across all climate change patterns. Additionally, investigation of the effects of a set of prescribed global mean temperature change scenarios show rapid increases in water scarcity due to climate change across many regions of the globe, up to 2°C, followed by stabilisation to 4°C.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The catchment of the River Thames, the principal river system in southern England, provides the main water supply for London but is highly vulnerable to changes in climate, land use and population. The river is eutrophic with significant algal blooms with phosphorus assumed to be the primary chemical indicator of ecosystem health. In the Thames Basin, phosphorus is available from point sources such as wastewater treatment plants and from diffuse sources such as agriculture. In order to predict vulnerability to future change, the integrated catchments model for phosphorus (INCA-P) has been applied to the river basin and used to assess the cost-effectiveness of a range of mitigation and adaptation strategies. It is shown that scenarios of future climate and land-use change will exacerbate the water quality problems, but a range of mitigation measures can improve the situation. A cost-effectiveness study has been undertaken to compare the economic benefits of each mitigation measure and to assess the phosphorus reductions achieved. The most effective strategy is to reduce fertilizer use by 20% together with the treatment of effluent to a high standard. Such measures will reduce the instream phosphorus concentrations to close to the EU Water Framework Directive target for the Thames.