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41.
The importance of wild edible herbaceous species to resource poor households in most rural economies within savannas has been little studied. This is because most of the herbs grow in impoverished species communities and lands, often referred to as 'marginal lands'. The aim of this paper is to conceptualize how the economics of wild edible herbs to households can be used to add value to total livelihoods and conservation within traditional communal areas of South Africa. Analysis of the economics of the consumption of wild edible herbs in Thorndale (Bushbuckridge district) of the Limpopo province is presented. The majority of households consumed wild edible herbs, averaging 15.4 kg dried weight per household per year and valued at $167 per household. The herbs were mostly harvested from uncultivated areas of farms, and rangelands. There was little correlation between household characteristics and the dependence on wild herbs for food. The local people noted a decline in the availability of the species, although not much is known about attempts to cultivate them. The only reasons attributed to the decline were nutrient poor soils and insufficient rains. With this background, developing a local strategy to sustain the species through cultivation by households was found to be feasible. A multiple-use system for the herbs, their improvement and value addition towards commercialization and increased household usage may result in wider acceptance and subsequent cultivation. Species diversity will be enhanced whilst conserving the land on which they grow. This multiple use system may include species roles in soil and water conservation.  相似文献   
42.
This perspective paper argues for an urgent need to monitor a set of 12 concrete, measurable indicators of food and water security in the Arctic over time. Such a quantitative indicator approach may be viewed as representing a reductionist rather than a holistic perspective, but is nevertheless necessary for actually knowing what reality aspects to monitor in order to accurately understand, quantify, and be able to project critical changes to food and water security of both indigenous and non-indigenous people in the Arctic. More relevant indicators may be developed in the future, taking us further toward reconciliation between reductionist and holistic approaches to change assessment and understanding. However, the potential of such further development to improved holistic change assessment is not an argument not to urgently start to monitor and quantify the changes in food and water security indicators that are immediately available and adequate for the Arctic context.  相似文献   
43.
Exposure to chemicals via diet is a major uptake pathway for many compounds but is often estimated in a rather generic way. We use a new model framework (NMF) with crop-specific models to predict the dietary intake by 4-5-year-old children and 14-75-year-old women of three environmental compounds from their background concentrations in soil and air. Calculated daily intakes of benzo(a)pyrene and 2,3,7,8-TCDD are in good agreement with measured results from diet studies. The major source of both compounds in human diet is deposition from air. Inhalation of air and ingestion of soil play a minor role. Children take up more than twice the amount than adults per kg bodyweight, due to higher consumption per kg bodyweight. Contrary, the methods for indirect human exposure suggested in the Technical Guidance Document (TGD) for chemical risk assessment in the EU lead to overprediction, due to unrealistic consumption data and a false root model.  相似文献   
44.
The distance between where food is produced and consumed is increasing, and is often taken as evidence of an unsustainable global food system. Seafood is a highly traded commodity yet seafood sustainability assessments do not typically consider the impacts of the movement of products beyond the fishery or farm. Here we use life cycle assessment to examine the carbon footprint of the production and distribution of select seafood products that are consumed in Australia and determine differences in the sustainability of imports and their domestically produced counterparts. We found that the distance food is transported is not the main determinant of food sustainability. Despite the increased distance between production and consumption, carbon footprints of meals from imported seafood are similar to meals consisting of domestically produced seafood, and sometimes lower, depending on the seafood consumed. In combining LCA with existing seafood sustainability criteria the trade-offs between sustainability targets become more apparent. Carbon ‘footprinting’ is one metric that can be incorporated in assessments of sustainability, thereby demonstrating a broader perspective of the environmental cost of food production and consumption.  相似文献   
45.
46.
The concept of substantial equivalence,introduced for the risk assessment of geneticallymodified (GM) food, is a reducing concept because itignores the context in which these products have beenproduced and brought to the consumer at the end of thefood chain. Food quality cannot be restricted to meresubstance and food acts on human beings not only atthe level of nutrition but also through theirrelationship to environment and society. To make thiscontext explicit, I will introduce an ``equivalencescale' for the evaluation of food chains (GM or notGM). By contrast with substantial equivalence, whichinvolves mainly quantitative, analytical methods ofevaluation, ``qualitative equivalence' refers to ``less'or non-substantial factors that require new methodsof evaluation based on qualitative principles.``Ethical equivalence' refers to factors that show themoral value contained in food products. To analyze thedifferent levels at which ethics is needed in foodchains, I will use the French principles: ``Liberty,Equality, Fraternity,' or freedom, equality,solidarity, and add a fourth principle:sustainability. Sustainability, solidarity, andfreedom can be applied to the evaluation ofenvironmental, socio-economic, and socio-culturalethical equivalence, respectively. Equality refers tojustice and should operate so as to guarantee thatsustainability, solidarity, and freedom are satisfied.I suggest that ethics can provide a basis for arenewal of the food chain concept. Besides QualityAssurance, it is now essential to develop an ``EthicalAssurance' and this equivalence scale could provide abasis to set up ``Ethical Assurance Standards' (EAS)for food chains.  相似文献   
47.
Environmental Management - Are societal wastes all bad? Some of them, including heat from power plants and certain organic wastes, have been demonstrated to be potentially valuable for growing...  相似文献   
48.
Helen Young 《Disasters》1986,10(4):250-257
During 1985 more than 5,000 tonnes of biscuits consisting of twenty-eight different brands were sent to Ethiopia and Sudan for emergency relief feeding. They were freely available to recognized agencies operating feeding programmes. Biscuits were popular with programme supervisors as few resources (fuel, staff and personnel) were required for their preparation and distribution. They were also popular with beneficiaries.
Different aspects of biscuits were examined and characteristics considered important included: nutritional composition, acceptability to beneficiaries, packaging, the biscuit dimensions, shelf-life and accompanying information (nutritional composition, ingredients and guidelines for use).
The results of a field study indicated that biscuits have a limited, but useful, role to play in the early stages of emergency relief. Based on the study, guidelines for both donors and users, on the use of food aid biscuits were developed, which emphasize their joint responsibility in minimizing the misuse of biscuits.  相似文献   
49.
Influence of maternal food availability on offspring dispersal   总被引:5,自引:0,他引:5  
Prenatal effects caused by the maternal environment during gestation are known to contribute to the phenotype of the offspring. Whether they have some adaptive value is currently under debate. We experimentally tested the existence of such a maternal effect (food availability during gestation) on dispersal of offspring in the common lizard (Lacerta vivipara). Pregnant females were captured and kept in the laboratory until parturition. During this period, females were offered two rates of food delivery. After parturition, we released mothers and offspring at the mother's capture point. Dispersal of young was significantly affected by the mother's nutrition. To our knowledge, this is the first evidence of a prenatal effect on dispersal. Offspring of well fed mothers dispersed at a higher rate than those of less well fed mothers. As current hypotheses clearly predict the opposite result, our evidence calls for their reassessment. Dispersers are not always the least fit individuals or those coming from the poorest environments.  相似文献   
50.
Bioassays are widely used to estimate ecological risks of contaminated sediments. We compared the results of three whole sediment bioassays, using the midge larva Chironomus riparius, the water louse Asellus aquaticus, and the mayfly nymph Ephoron virgo. We used sediments from sixteen locations in the Dutch Rhine-Meuse Delta that differed in level of contamination. Previously developed protocols for each bioassay were followed, which differed in sediment pretreatment, replication, and food availability. The Chironomus bioassay was conducted in situ, whereas the other two were conducted in the laboratory. The measured endpoints, survival and growth, were related to contaminant levels in the sediment and to food quantity in water and sediment.

Only the response of A. aquaticus in the bioassay was correlated with sediment contamination. Food availability in overlying water was much more important for C. riparius and E. virgo, thereby masking potential sediment contaminant effects. We conclude that growth of A. aquaticus was depressed by sediment contamination, whereas growth of E. virgo and C. riparius was stimulated by seston food quantity. We discuss that the trophic state of the ecosystem largely affects the ecological risks of contaminated sediments.  相似文献   

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