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331.
An investigation was carried out to determine the microbial load in poultry litter used as feed supplement in rabbit diets. Before heat treatment by deep stacking the poultry litter, samples of the litter were collected to assay for microbial load at the Microbiology Laboratory of the Rivers State University of Science and Technology, Port Harcourt, Nigeria. Results obtained showed that before heat-treating the poultry litter, Escherichia coli, Salmonella, Mycobacterium, Clostridium and Staphylococcus were isolated at 41, 37, 37, 41 and 42°C, respectively. The results obtained also indicate that no pathogen was isolated after heat treatment of between 40 and 55°C for 21 days. This study justifies the suitability of using poultry litter as a feed supplement.  相似文献   
332.
The compelling need to harness the potentials of the numerous agro-industrial by-products and the so-called “wastes” as part replacement for the more expensive conventional feed ingredients have been seriously expressed. This need has arisen mainly from the increasing demand and supply deficit of conventional feed resources with a concomitant sharp rise in their cost prices. The net effect of increased unit cost of the conventional feed resources is increased cost of the compounded rations, which by extension gives rise to increased cost of meat and animal products. It then becomes highly imperative that other sources for rapid livestock output to meet the growing human demands for animal protein foods are sourced. Such other sources should be cheap and nutritionally adequate for feeding animals with the aim of lowering the cost of producing meat. One of such measure is the recycling of poultry litter as part replacement for soya bean in livestock nutrition. Poultry litter is the by-product of poultry production, which should be managed in an environmentally friendly manner. As observed in this study, poultry litter contains 20% crude protein, 621.41 ME kcal kg?1, and substantial amounts of minerals that could be exploited in feeding livestock. This study has explored the possibility of including poultry litter in diets in view of its contents.  相似文献   
333.

Agricultural systems have become increasingly industrialized and mechanized, relying on machinery and chemical inputs, rather than people and natural processes, to increase yields of food. The trend towards an increasingly globalised food system encourages unsustainable transportation of food around the world. Agricultural intensification and the globalisation of the agrofood chain has resulted in adverse environmental, social and economic consequences impeding moves towards sustainability. Organic farming can overcome many of the environmental problems associated with agricultural intensification. However, it does not have the potential to fully address the social and economic problems caused by the globalisation of the food system. Organic farming must be combined with local and regional sourcing of food products, for instance through forms of direct marketing of organic produce. Direct marketing schemes such as farmers' markets, food box delivery schemes and community-supported agriculture are all projects which, if managed with sustainability as the prime objective, have the potential to move towards a more socially, environmentally and economically sustainable agrofood system.  相似文献   
334.
Humanitarian food assistance aims to meet short‐term emergency needs, yet often it is sustained over many years and develops its own systems and infrastructure that interact with local governance and local communities. This paper explores the links between participation and local governance, as well as the implications for exclusion of certain groups, the dignity of those involved, and protection issues. The paper proposes a framework for reviewing the governance functions and capacities of local Food Relief Committees, based on the following criteria: accountability; gender equity; legitimacy and authority; representativeness; responsiveness; and transparency. A case study of the Darfur region reviews how local governance evolves as a result of both the wider conflict and of adapting to the international humanitarian system, itself a form of governance. The paper concludes by proposing three strategies for enhancing participation and applying lessons learned: improved analysis of participation; linking programming strategies and protection; and taking account of governance functions and capacities.  相似文献   
335.
Satellite telemetry data from 17 juvenile loggerhead turtles (43.5–66.5 cm straight carapace length) were used in conjunction with oceanographic data to analyze the influence of regional and seasonal oceanography on dive behavior in the North Pacific Ocean. Combined dive behavior for all individuals showed that turtles spent more than 80% of their time at depths <5 m, and more than 90% of their time at depths <15 m. Multivariate classifications of dive data revealed four major dive types, three representing deeper, longer dives, and one representing shallower dives shorter in duration. Turtles exhibited variability in these dive types across oceanographic regions, with deeper, longer dives in the Hawaii longline swordfish fishing grounds during the first quarter of the year, as well as in the Kuroshio Extension Bifurcation Region and the region near the Baja California Peninsula, Mexico. Turtles in the Kuroshio Extension Bifurcation Region also exhibited dive variability associated with mesoscale eddy features, with turtles making deeper, longer dives while associated with the strongest total kinetic energy. Turtles in the central North Pacific exhibited seasonality in dive behavior that appeared to reflect synchronous latitudinal movements with the North Pacific Subtropical Front and the associated seasonal, large-scale oceanography. Turtles made deeper, longer dives during the first quarter of the year within this region, the reported time and area where the highest loggerhead bycatch occurs by the longline fishery. These results represent the first comprehensive study of dive data for this species in this region. The increased understanding of juvenile loggerhead dive behavior and the influences of oceanography on dive variability should provide further insight into why interactions with longline fisheries occur and suggest methods for reducing the bycatch of this threatened species.  相似文献   
336.
公用事业已经对环境质量产生重要的影响,特别是在市区.初看起来,放宽限制或公用事业的私有化似乎提供不了任何环境效益.然而,如果在一个合适的管理法律体制内发生这样一个变化,结果实际上是提高了人们对可持续发展的注意.关于这一点,给出了一个关于改善公路运输的可持续发展性机会的实例研究.  相似文献   
337.
The persistence of glyphosate and its primary metabolite AMPA (aminomethylphosphonic acid) was monitored in two areas in Southern Greece (Peza, Crete and Chora Trifilias, Peloponnese) with a known history of glyphosate use, and the levels of residues were linked to spray operators’ activities in the respective areas. A total of 170 samples were collected and analysed from both areas during a 3-year monitoring study. A new method (Impact Assessment Procedure - IAP) designed to assess potential impacts to the environment caused by growers’ activities, was utilised in the explanation of the results. The level of residues was compared to the predicted environmental concentrations in soil. The ratio of the measured concentrations to the predicted environmental concentrations (MCs/PECs) was >?1 in Chora the first 2 years of sampling and <?1 in the third year, whilst the MCs/PECs ratio was <?1 in Peza, throughout the whole monitoring period. The compliance to the instructions for best handling practices, which operators received during the monitoring period, was reflected in the amount of residues and the MCs/PECs ratio in the second and especially the third sampling year. Differences in the level of residues between areas as well as sampling sites of the same area were identified. AMPA persisted longer than the parent compound glyphosate in both areas.  相似文献   
338.
Several studies have indicated the importance of understanding farmers’ perceptions of risks associated with climate change, the adaptation strategies they employ and factors that affect adaptive capacity. This study aimed to understand smallholder farmers’ perceptions of climate change, adaptation strategies and adaptive capacity in the semiarid Matungulu Sub-County, Eastern Kenya. A participatory approach, using three climate roundtables, was conducted to enhance community participation and understanding of climate change issues. The study showed that farmers’ perceptions concerning climate change are influenced by past experiences of weather extremes that have affected production levels and farm incomes. The farmers have made strategic responses to manage risks posed by climate change. However, they face several challenges in adaptation such as inadequate technical knowledge, low financial resources and inadequate land size. Further, the study showed that climate roundtables is a successful participatory approach that can give effective insights for smallholder farmers to understand agricultural vulnerability, climate change and their adaptation strategies.  相似文献   
339.
A formal model for consensus and negotiation in environmental management   总被引:8,自引:0,他引:8  
Environmental management decisions typically lie at the interface of science and public policy. Consequently, these decisions involve a number of stakeholders with competing agendas and vested interests in the ultimate decision. In such cases, it is appropriate to adopt formal methods for consensus building to ensure transparent and repeatable decisions. In this paper, we use an environmental management case study to demonstrate the utility of a mathematical consensus convergence model in aggregating values (or weights) across groups. Consensus models are applicable when all parties agree to negotiate in order to resolve conflict. The advantage of this method is that it does not require that all members of the group reach agreement, often an impossible task in group decision making. Instead, it uses philosophical foundations in consensus building to aggregate group members' values in a way that guarantees convergence towards a single consensual value that summarizes the group position. We highlight current problems with ad hoc consensus and negotiation methods, provide justification for the adoption of formal consensus convergence models and compare the consensus convergence model with currently used methods for aggregating values across a group in a decision making context. The model provides a simple and transparent decision support tool for group decision making that is straightforward to implement.  相似文献   
340.
To determine to what extent dew water is potable without further treatment, a thorough set of chemical and biological analyses were performed on 10 samples of dew water collected on a large scale radiative collector (29.83 m2) in Ajaccio (Corsica Island, France), between 21 May 2002 and 5 Mar. 2003. Samples were collected following four protocols according to the dew volume amount and 48 parameters (ions, minerals, and bacteria) were analyzed and compared to French and European Union legislation and also World Health Organization (WHO) recommendations. Aluminum and Fe were the main pollutants whose concentrations were significantly larger than recommended. Their presence is due to local deposition of aerosols coming from the Sahara (a characteristic of the Mediterranean basin). A large number of biologically cultivable microorganisms were found, together with bacteria typical of fecal contamination. For dew water to be potable with respect to present legislation at the Ajaccio site, it should be disinfected and treated for turbidity.  相似文献   
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