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771.
During the last two decades Indonesia has experienced immense forest and land fires. Often these fires are associated with extended drought and widespread use of fire to clear previously logged forest and other degraded land in preparation for oil palm, rubber, or pulpwood plantations. There are many reasons for the use of fire in land clearing activities, but probably the most important one is economics. There is still acceptance that fire is the cheapest, fastest, and most effective land clearing method with the added benefit of providing nutrients from ash residues. This paper provides a review of existing information on the financial costs and benefits of using fire for land clearing in agriculture and forestry plantations as compared with zero-burning techniques. The findings indicate that the economic advantage of fire use varies widely and depends on many factors, such as soil fertility, vegetation density, labour cost, equipment and training costs, and the costs of fire management. For large-scale land clearing, the financial analysis of the costs and benefits of fire versus zero-burning shows that when applied to low-volume vegetation, zero-burning methods are not more expensive than burning – and may actually be more cost effective in the long term. This is the case for clearing oil palm or rubber plantations for replanting, low secondary vegetation, and heavily logged-over forest. Under high-volume forest conditions, burning remains less expensive because it is more difficult, time consuming, and costly to dispose of high volumes of piled wood mechanically.  相似文献   
772.
This paper examines the legitimacy, viability and efficiency of the European Union Solidarity Fund by asking whether the Fund meets its stated purpose of providing solidarity within the EU, whether it is sufficiently capitalized and if it promotes disaster risk reduction in Europe. In examining these questions, we make use of ADAM models of disaster risks throughout Europe. We conclude that the Solidarity Fund falls short on all three counts, and we suggest possible alternatives. Most far-reaching, we explore whether the EUSF could support insurance systems in Europe by, among other possible activities, capitalizing national public-private insurance programs and providing support for government risk transfer. This would leverage the Fund’s capital and would overcome barriers to the provision of private and public sector insurance in uncertain catastrophe markets. It would also make insurance more affordable to Europe’s most vulnerable communities. Finally, it would reduce the disincentives for risk reduction inherent in post-disaster assistance.  相似文献   
773.
Reindeer (Rangifer tarandus) eat and utilize lichens as an important source of energy and nutrients in winter. Lichens synthesize and accumulate a wide variety of phenolic secondary compounds, such as usnic acid, as a defense against herbivores and to protect against damage by UV-light in solar radiation. We have examined where and to what extent these phenolic compounds are degraded in the digestive tract of the reindeer, with particular focus on usnic acid. Three male reindeer were given ad libitum access to a control diet containing no usnic acid for three weeks and then fed lichens ad libitum (primarily Cladonia stellaris) containing 9.1 mg/g DM usnic acid for 4 weeks. Usnic acid intake in reindeer on the lichen diet was 91–117 mg/kg BM/day. In spite of this, no trace of usnic acid or conjugates of usnic acid was found either in fresh rumen fluid, urine, or feces. This suggests that usnic acid is rapidly degraded by rumen microbes, and that it consequently is not absorbed by the animal. This apparent ability to detoxify lichen phenolic compounds may gain increased importance with future enhanced UV-B radiation expected to cause increased protective usnic acid/phenol production in lichens.  相似文献   
774.
Slum dwellers response to flooding events in the megacities of India   总被引:3,自引:0,他引:3  
Megacities in developing countries are rapidly transforming places. Under the impetus of global change processes and consequent transformations at the environmental, social, cultural, political and economical scales; factors causing disasters and losses are changing every day. These changes are also altering society’s ability to respond to hazard events. This paper examines the response of slum dwellers who are the most vulnerable and marginal section of urban population and often located in places with high hazard risk with less or no means to reduce the impact of flood events. Marginal population groups in megacities suffer the negative consequences of large scale global change processes and do not benefit from the risk mitigation strategies adopted by city authorities. The paper therefore argues that people living in informal settlements instead have to employ a combination of structural means and complex networks of assistance to recover from floods. Based on the results deduced from data collected with the help of household surveys in the slums of Mumbai, the study demonstrates the types of coping strategies used by slum dwellers and the changing characteristics of these mechanisms under the influence of global change processes in megacities. Furthermore, results show that capacity to respond is not equally distributed among slum dwellers due to underlying socio cultural divisions and emerging economic and political constraints. The paper concludes that to address existing discrepancies in urban societies and within slum settlements, flood mitigation strategies will have to be (1) more inclusive of marginal population (2) sensitive to the limitations and scope of old and new social structures and (3) incorporate innovative networks of support to deal with the consequences of global change.  相似文献   
775.
Different sources were consulted to obtain information on the occurrence of viruses in bivalve molluscs on the European market. Twenty-six peer-reviewed articles were identified reporting on the molecular detection of viral RNA in 4,260 samples in total. The data obtained will be presented geographically on virus types detected, the origin and treatment of the shellfish, and the detection technique applied. The data demonstrate that viral RNA can be detected in shellfish from polluted areas, in depurated shellfish as well as those for human consumption. The European Rapid Alert System for Food and Feed (RASFF) database was consulted as another source. Twenty-eight notifications were identified on the presence of hepatitis A virus or norovirus in shellfish on the European market. The most recent report of the European laboratory network was referred to, to gain insight into the laboratory capability at present for the analyses of shellfish on the presence of viruses. Approximately 67% of 27 participating laboratories obtained intended results for all samples, consisting of lenticules loaded with 103 copies norovirus (genogroup I (GGI) and/or genogroup II (GGII)) and/or 1 × 105–8 × 104 copies of hepatitis A virus. From 1993, there has been a continuous development of molecular detection techniques and tools have been described to ensure quality assurance. End product testing will, however, not be achievable. As depuration has been shown not to be effective for the complete elimination of viruses, shellfish should not be in contact with faecal contaminated water in order to minimise the risk of shellfish-transmittable viral diseases.  相似文献   
776.
This paper describes how relatively detailed knowledge about probabilities of natural hazards can be used to make decisions to develop areas and control the risk within hazard zones. The assessment serves two purposes. First, it shows how information can support decisions. Second, decision criteria put leads on what information is required. This is helpful to identify unavailable information. We show by an example from a land-slide prone area in Norway how a relatively reliable estimate of the probability of slides ends up in a rather uncertain estimate of the risk. Uncertainty about the risk represented by natural hazards imply great challenges to the development of adaptation policies to meet climate change, but they are required. We develop a simplified criterion for optimal adaptation, and estimate the added social value required to defend development in hazard prone areas instead of developing a risk-free alternative. The value is estimated between 0 and 0.40 Euros per Euro invested in the case area, depending on type of slide, category of asset and other costs that occur in the wake of slides.  相似文献   
777.
Climate change potentially brings continuous and unpredictable changes in weather patterns. Consequently, it calls for institutions that promote the adaptive capacity of society and allow society to modify its institutions at a rate commensurate with the rate of environmental change. Institutions, traditionally conservative and reactive, will now have to support social actors to proactively respond through planned processes and deliberate steps, but also through cherishing and encouraging spontaneous and autonomous change, as well as allowing for institutional redesign. This paper addresses the question: How can the inherent characteristics of institutions to stimulate the capacity of society to adapt to climate change from local through to national level be assessed? On the basis of a literature review and several brainstorm sessions, this paper presents six dimensions: Variety, learning capacity, room for autonomous change, leadership, availability of resources and fair governance. These dimensions and their 22 criteria form the Adaptive Capacity Wheel. This wheel can help academics and social actors to assess if institutions stimulate the adaptive capacity of society to respond to climate change; and to focus on whether and how institutions need to be redesigned. This paper also briefly demonstrates the application of this Adaptive Capacity Wheel to different institutions.  相似文献   
778.
Pigeons were released at two sites of equal distance from the loft, one within a magnetic anomaly, the other in magnetically quiet terrain, and their tracks were recorded with the help of GPS receivers. A comparison of the beginning of the tracks revealed striking differences: within the anomaly, the initial phase lasted longer, and the distance flown was longer, with the pigeons' headings considerably farther from the home direction. During the following departure phase, the birds were well homeward oriented at the magnetically quiet site, whereas they continued to be disoriented within the anomaly. Comparing the tracks in the anomaly with the underlying magnetic contours shows considerable differences between individuals, without a common pattern emerging. The differences in magnetic intensity along the pigeons' path do not differ from a random distribution of intensity differences around the release site, indicating that the magnetic contours do not directly affect the pigeons' routes. Within the anomaly, pigeons take longer until their flights are oriented, but 5 km from the release point, the birds, still within the anomaly, are also significantly oriented in the home direction. These findings support the assumption that magnetically anomalous conditions initially interfere with the pigeons' navigational processes, with birds showing rather individual responses in their attempts to overcome these problems.  相似文献   
779.
The goal of this study was to better quantify the degree of viral contamination of tomato and cucumber in relationship to virus type, soil type, and irrigation method. Tomatoes and cucumbers were grown in ten-gallon (37.8 L) buckets filled with Pima clay loam or Brazito sandy loam soils. Plants were irrigated with secondary wastewater effluent using surface drip irrigation or subsurface drip irrigation. At specified time intervals irrigation water was seeded with bacteriophages MS-2 and P22, poliovirus type 1 (PV1), enteric adenovirus 40 (Ead 40), and hepatitis A virus. Surface drip irrigation always resulted in viral contamination of both the above and below ground parts of both crops. The roots showed the greatest level of contamination, followed by leaves and fruits. In contrast, with subsurface drip irrigation no viruses were detected in any of the above ground plant surfaces. It was found that under similar soil type and irrigation method, risk of crop contamination was similar for all of the viruses studied. It can be concluded that method of irrigation is the single most critical factor in the contamination trend of different parts of crop plants. Plant parts can be categorized into three groups (root, stem, and leaf/fruit) based on the risk of viral contamination from irrigation water.  相似文献   
780.
The purpose of this study was to quantify the transfer of viral and bacterial pathogens in water used to dilute pesticides sprayed onto the surfaces of cantaloupe, iceberg lettuce, and bell peppers. The average percent transfer of bacteria was estimated to range from 0.00021 to 9.4%, while average viral transfer ranged from 0.055 to 4.2%, depending on the type of produce. Based on these values the concentrations of hepatitis A virus (HAV) and Salmonella in water necessary to achieve a 1:10,000 annual risk of infection were calculated. Under worst case scenario assumptions, in which a pesticide is applied on the same day that the produce is harvested and when maximum transfer values are used, concentrations of 1.5 × 10−3 CFU Salmonella or 2.7 × 10−7 MPN HAV per 100 ml of the water used for application would result in 1:10,000 annual infection risk to anyone who consumes the fresh produce. If harvesting does not occur until at least 14 days after the application, to produce the same risk of infection, the numbers of Salmonella in 100 ml of water used to dilute the pesticides will be greater by up to five orders of magnitude, while the HAV numbers will have increased by up to two orders of magnitude. Based on the reported concentrations of enteric viruses in surface and ground waters in the United States, a 1:10,000 annual risk of infection could easily be exceeded with some groundwater sources used in the United States. To reduce the risks associated with the consumption of fresh produce, water used to prepare pesticides in spray applications should be evaluated for its microbiological quality.  相似文献   
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