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291.
Catherine Bragg Glenn Gibson Haleigh King Ashley A. Lefler Faustin Ntoubandi 《Disasters》2018,42(1):3-18
There is a general assumption, based on macroeconomic studies, that remittances will rise following major sudden‐onset natural disasters. This is confirmed by a few assessments involving country‐specific research, and usually short‐term data. This study, questioning conventional wisdom, reviewed and graphed annual and quarterly remittance flows using International Monetary Fund and World Bank data from 2000–14 for 12 countries that confronted 18 major natural disasters. It found that, regardless of event type, annual remittances rose steadily from 2000–14 except for after the 2008–09 financial crisis. Post disaster, there was a quarterly increase in the majority of cases (confirming previous research) but there was seldom an annual increase in the year of the disaster greater than the average annual increase in 2000–14. It appears that remittance senders rush to provide assistance after a natural disaster, but since their own financial situation has not changed, the immediate increase is compensated by a later decrease. 相似文献
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This study empirically estimates the multiple benefits of a subsidy policy that would offer payments to farmers in return for the adoption of conservation tillage, and compares the outcomes of alternative targeting designs for such a policy. The least-cost incentive payment policy schemes are simulated for the State of Iowa by using the data for roughly 12,000 National Resource Inventory (NRI) points. We use an economic conservation tillage adoption model to evaluate the costs of adoption and a physical process simulation model (EPIC) to estimate the environmental benefits due to adoption at each of the NRI points.Two targeting options are considered. We assess the costs and environmental consequences of a practice-based policy instrument (which maximizes the acres of land in conservation tillage, regardless of its level of environmental benefits) and contrast it to a performance-based instrument (which yields the highest amount of environmental benefits per dollar spent). Carbon sequestration in agricultural soils, reduction of soil erosion by wind and water, and the reduction in nitrogen runoff are considered as possible targets for the performance-based instruments. We find that the practice-based instrument provides high proportions of the four benefits relative to the policies that target the benefits directly, especially at the higher policy budget levels. Similarly, we estimate that targeting one of the four benefits individually provides high percentages of the other benefits as compared with the amounts of the benefits obtainable if they were targeted directly. 相似文献
294.
This article outlines a methodology to help agencies better determine whether or not relief seed is needed by farmers affected by disaster. A brief review of current seed needs assessment procedures in southern Somalia and Mozambique illustrates problems of knowing which crops and households are affected, the importance of seed access (not just availability) and the need to plan interventions earlier than at present. The development of a Seed Systems Profile (SSP) is proposed to understand better both the socio-economic and agro-ecological aspects of farmers' seed systems. A five-step framework for assessing seed systems in disaster situations is also presented. These tools are currently being tested and further refined in Mozambique. A better understanding of farmers' seed systems will allow for the development of relief and rehabilitation interventions that effectively enhance the resilience and reduce the vulnerability of these systems. 相似文献
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Robles C Greff S Pasqualini V Garzino S Bousquet-Mélou A Fernandez C Korboulewsky N Bonin G 《Journal of environmental quality》2003,32(6):2265-2271
The aim of the present study is to assess whether certain ecophysiological responses (contents of total phenols, total proanthocyanidins, and total and simple flavonols), in the needles of Aleppo pines (Pinus halepensis Mill.) may be valid bioindicators for the assessment of the air quality. Samples were taken at five natural sites polluted by various pollutants (NO, NO2, other NOx, SO2, and O3). The results show a decrease in total phenol concentrations with levels of nitrogen oxide pollutions (significant negative correlations between the total phenol concentrations and concentrations of NO, NO2, and other NOx). Total flavonoids (total flavonols and proanthocyanidins) are useful bioindicators for ozone pollution (significant negative correlations between total proanthocyanidins and the concentrations of ozone and significant positive correlations between total flavonols and the ozone pollution). Sulfur dioxide pollution is distinguished by low concentrations in quercetin, isorhamnetin, and kaempferol (significant negative correlations between these simple flavonols and the concentrations of SO2). This work confirms the strong interest of using the phenolic compounds of Pinus halepensis as biological indicators of air quality. 相似文献
299.
Despite reductions in atmospheric SO4(2-) deposition and resultant decreases in surface water acidity, widespread biological recovery from acidification has not yet been documented. Temporal trends in crustacean zooplankton species richness (number of species) and composition were examined between 1971-2000 in 46 Killarney Park lakes, Ontario, Canada, to assess the degree of biological recovery in lakes with significant water quality improvements, i.e. pH now > 6, compared to 2 other groups: i) lakes which never acidified; and ii) lakes which are still acidified (pH < 6). Time trends in species richness could not be distinguished among the 3 groups of lakes, nor did changes in species richness indicate recovery. In contrast, the zooplankton community composition of lakes in which the pH increased to above 6, as measured by a multivariate index of species abundances, changed from a "damaged" state to one typical of neutral lakes. Some recovery in composition was also documented for the acidic lakes. While still acidic, the pH levels of these lakes have risen. The extent and pace of recovery in Killarney Provincial Park bodes well for the future of other acidified regions in North America and Europe. 相似文献
300.