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91.
Darío A. Maggioni Marcelo L. Signorini Nicolás Michlig María R. Repetti Mirna E. Sigrist 《Journal of environmental science and health. Part. B》2017,52(4):256-266
A chronic dietary risk assessment for pesticide residues was conducted for four age groups of the Argentinian population following the procedure recommended by the WHO. The National Theoretical Maximum Daily Intake (NTMDI) for 308 pesticides was calculated for the first time, using the Maximum Residue Limits (MRLs) from several Argentinean regulations and food consumption data from a comprehensive National Nutrition and Health Survey. The risk was estimated by comparing the TMDI with the Acceptable Daily Intakes (ADI) identified by various sources. Furthermore, for each of the compounds with a TMDI >65% of the ADI, a probabilistic analysis was conducted to quantify the probability of exceeding the ADI. In this study 27, 22, 10, and 6 active ingredients (a.i.) were estimated to exceed the 100% of the ADI for the different population groups: 6–23 month-old children, 2–5 year-old children, pregnant women, and 10–49 year-old women, respectively. Some of these ADI-exceeding compounds (carbofuran, diazinon, dichlorvos, dimethoate, oxydemeton-methyl and methyl bromide) were found in all four of these groups. Milk, apples, potatoes, and tomatoes were the foods that contributed most to the intake of these pesticides. The study is of primary importance for the improvement of risk assessment, regulations, and monitoring activities. 相似文献
92.
张秋柳 《中国人口.资源与环境》2011,21(9)
在经济发展、消费升级、资源短缺和环境问题凸显的新的外部环境背景下,本文引入了国外新兴的食品系统理论,探讨并提出了可持续的食物安全保障的新观念.食物安全始终是中国经济发展、社会稳定和国家自立的基础.国内多数学者仍然用30年前食物匮乏时期的思路来研究现代的食物安全问题,其结果导致研究结论与现实情况不符.如何在节约资源、减少浪费的同时又能够满足人们不断升级的食物消费需求,是对未来食物安全保障的新要求.本文首先分析了我国食物安全研究的现状,指出了不足和问题,然后引入国外新兴的食品系统理论,在探讨其概念内涵的基础上,剖析了食品系统与食物安全的关系,影响食物安全的因素和研究视角,并进一步提炼出基于食品系统理论的新的食物安全保障观念,为我国研究食物安全提供借鉴. 相似文献
93.
Nina E. Cohen Frans W. A. Brom Elsbeth N. Stassen 《Journal of Agricultural and Environmental Ethics》2009,22(4):341-359
In this paper, we present and defend the theoretical framework of an empirical model to describe people’s fundamental moral
attitudes (FMAs) to animals, the stratification of FMAs in society and the role of FMAs in judgment on the culling of healthy
animals in an animal disease epidemic. We used philosophical animal ethics theories to understand the moral basis of FMA convictions.
Moreover, these theories provide us with a moral language for communication between animal ethics, FMAs, and public debates.
We defend that FMA is a two-layered concept. The first layer consists of deeply felt convictions about animals. The second
layer consists of convictions derived from the first layer to serve as arguments in a debate on animal issues. In a debate,
the latter convictions are variable, depending on the animal issue in a specific context, time, and place. This variability
facilitates finding common ground in an animal issue between actors with opposing convictions. 相似文献
94.
Intensification of food production in tropical landscapes in the absence of land‐use planning can pose a major threat to biological diversity. Decisions on whether to spatially integrate or segregate lands for production and conservation depend in part on the functional relations between biological diversity and agricultural productivity. We measured diversity, density, and species composition of birds along a gradient of production intensification on an agricultural frontier of the Argentine Chaco, where dry tropical forests are cleared for cattle production. Bird species diversity in intact forests was higher than in any type of cattle‐production system. Bird species richness decreased nonlinearly as cattle yield increased. Intermediate‐intensity silvopastoral systems, those in which forest understory is selectively cleared to grow pastures of non‐native plants beneath the tree canopy, produced 80% of the mean cattle yield obtained in pastures on cleared areas and were occupied by 70–90% of the number of bird species present in the nearest forest fragments. Densities of >50% of bird species were significantly lower in open pastures than in silvopastoral systems. Therefore, intermediate‐intensity silvopastoral systems may have the greatest potential to sustain cattle yield and conserve a large percentage of bird species. However, compared with low‐intensity production systems, in which forest structure and extent were intact, intermediate‐intensity silvopastoral systems supported significantly fewer forest‐restricted bird species and fewer frugivorous birds. These data suggest that the integration of production and conservation through intermediate‐intensity silvopastoral systems combined with the protection of forest fragments may be required to maintain cattle yield, bird diversity, and conservation of forest‐restricted species in this agricultural frontier. Compromisos entre la Producción de Ganado y la Conservación de Aves en una Frontera Agrícola del Gran Chaco de Argentina 相似文献
95.
David Sztybel 《Journal of Agricultural and Environmental Ethics》2001,14(3):259-273
Even if animal liberation were to be adopted, would rights for animals be redundant – or even deleterious? Such an objection, most prominently voiced by L. W. Sumner and Paul W. Taylor, is misguided, risks an anthropocentric and anthropomorphic conception of autonomy and freedom, overly agent-centered rights conceptions, and an overlooking of the likely harmful consequences of positing rights for humans but not for nonhuman animals. The objection in question also stems from an overly pessimistic construal of autonomy-infringements thought to result from extending rights to animals, and also, of confusions that supposedly may ensue from ascribing animal rights. Whether or not a case for animal liberation and/or animal rights can cogently be made, the redundancy-or-worse objection to animal rights need pose no barrier. 相似文献
96.
Veronica M. Bueno Kevin R. Burgio Carrie A. Cizauskas Christopher F. Clements Dana P. Seidel Nyeema C. Harris 《Conservation biology》2016,30(4):724-733
Parasitic species, which depend directly on host species for their survival, represent a major regulatory force in ecosystems and a significant component of Earth's biodiversity. Yet the negative impacts of parasites observed at the host level have motivated a conservation paradigm of eradication, moving us farther from attainment of taxonomically unbiased conservation goals. Despite a growing body of literature highlighting the importance of parasite‐inclusive conservation, most parasite species remain understudied, underfunded, and underappreciated. We argue the protection of parasitic biodiversity requires a paradigm shift in the perception and valuation of their role as consumer species, similar to that of apex predators in the mid‐20th century. Beyond recognizing parasites as vital trophic regulators, existing tools available to conservation practitioners should explicitly account for the unique threats facing dependent species. We built upon concepts from epidemiology and economics (e.g., host‐density threshold and cost‐benefit analysis) to devise novel metrics of margin of error and minimum investment for parasite conservation. We define margin of error as the risk of accidental host extinction from misestimating equilibrium population sizes and predicted oscillations, while minimum investment represents the cost associated with conserving the additional hosts required to maintain viable parasite populations. This framework will aid in the identification of readily conserved parasites that present minimal health risks. To establish parasite conservation, we propose an extension of population viability analysis for host–parasite assemblages to assess extinction risk. In the direst cases, ex situ breeding programs for parasites should be evaluated to maximize success without undermining host protection. Though parasitic species pose a considerable conservation challenge, adaptations to conservation tools will help protect parasite biodiversity in the face of an uncertain environmental future. 相似文献
97.
Brian Furze 《Journal of Agricultural and Environmental Ethics》1989,2(1):59-67
Food is a basic human need and therefore a basic human right. While food output has increased to a level where there is enough food produced to feed the world, still millions starve. Using the concept of capitalist world economy as a framework, this paper provides a structural analysis of the food production and distribution system within monopoly capitalism and its implications for countries of the underdeveloped world. Focusing on the impact of a dominant world food supply system on indigenous systems (particularly through the rise of science, technology, and monopoly capital), considerations relating to environmental use and food production and distribution are raised. Finally a call is made for a new agricultural ethic. 相似文献
98.
Environmental degradation, competition for resources, increasing food demands, and the integration of agriculture into the
international economy threaten the sustainability of many food production systems. Despite these concerns, the concept of
sustainable food production systems remains unclear, and recent attempts to appraise sustainability have been hampered by
conceptual inconsistencies and the absence of workable definitions. Six perspectives are shown to underpin the concept. Environmental
accounting identifies biophysical limits for agriculture. Sustained yield refers to output levels that can be maintained continuously.
Carrying capacity defines maximum population levels that can be supported in perpetuity. Production unit viability refers
to the capacity of primary producers to remain in agriculture. Product supply and security focuses on the adequacy of food
supplies. Equity is concerned with the spatial and temporal distribution of products dervied from resource use. Many studies
into sustainable agriculture cover more than one of these perspectives, indicating the concept is complex and embraces issues
relating to the biophysical, social, and economic environments. Clarification of the concept would facilitate the development
of frameworks and analytical systems for appraising the sustainability of food production systems.
LRRC Contribution No. 90–46. 相似文献
99.
100.