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991.
Yu. V. Gerasimov 《Russian Journal of Ecology》2007,38(6):430-435
In the course of studies on mass fish species (bream and roach) in water bodies of the Upper Volga basin, intraspecific groups of individuals have been distinguished. Conditions and possible mechanisms of spatial differentiation of these groups are considered. The intrapopulation divergence of individuals by some adaptive characters, primarily behavioral, enables them to utilize alternative resources, which provides for more efficient use of the environment by populations. 相似文献
992.
Buzz Sharp 《Disasters》2007,31(S1):S104-S123
In the post-Comprehensive Peace Agreement (CPA) era a greater impact on the unacceptably high prevalence of child malnutrition is more likely to come from additional investment and attention to education, health, hygiene, sanitation and childcare practices than from expanded food aid interventions. The negligible impact of food aid on malnutrition, although most commonly challenged on the quality of needs assessments, is equally attributable to the timing of deliveries, and a dysfunctional distribution system. Comparatively few resources have been allocated to strengthen skills for assessing, analysing and understanding community priorities, local economies, and social safety nets. A more thoughtful allocation of scarce funds could have more impact if a range of alternative responses was considered. Participation in and commitment to a more independent livelihoods analytical forum would improve communication with the new government, local leaders and other partners, as well as providing a platform for reaching consensus on both humanitarian and development planning over the next five years. 相似文献
993.
Individuals’ food choices are intimately connected to their self-images and world views. Some dietary choices adopted by consumers
pose restrictions on their use of genetically modified food (GMF). It is quite generally agreed that some kind of labeling
is necessary for respecting consumers’ autonomy of choice regarding GMF. In this paper, we ask whether the current practice of mandatory
labeling of GMF products in the European Union is a sufficient administrative procedure for respecting consumers’ autonomy. Three issues concerning this question are discussed. First,
we argue that labeling needs to be accompanied by relevant and understandable information on genetic modification, genetically
modified food, and the European practice of GMF labeling. Second, we claim that this type of informing makes it less likely
that consumers start to avoid GMF products just because labels make them suspicious of the products. It is further noted that
even though some consumers may react to labels this way, labels do not restrict their autonomy of choice. Third, a need for
more precise labels indicating the source of the transferred gene is considered. It is found out that such labels are not
morally necessary when also non-GMF products are available and no relevant differences (such as differences in price and healthiness)
exist between them and GMF products. However, in some other cases more precise labels may be needed for respecting consumers’
autonomy of choice. 相似文献
994.
Getting the Scale Right: A Comparison of Analytical Methods for Vulnerability Assessment and Household-level Targeting 总被引:2,自引:0,他引:2
This paper introduces broad concepts of vulnerability, food security and famine. It argues that the concepts and theories driving development and implementation of vulnerability assessment tools are related to their utility. The review concludes that socio-geographic scale is a key issue, and challenge. It analyses three vulnerability assessment (VA) methods, using Ethiopia as a case study. Facing the challenges of vulnerability assessment and early warning requires providing accurate information at the required scale, useful for multiple decision-makers within realistic institutional capacities. 相似文献
995.
As nations develop policies for low-carbon transitions, conflicts with existing policies and planning tools are leading to competing demands for land and other resources. This raises fundamental questions over how multiple demands can best be managed. Taking the UK as an empirical example, this paper critiques current policies and practices to explore the interdependencies at the water-energy-food nexus. It considers how current land uses and related policies affect the UK’s resilience to climate change, setting out an agenda for research and practice relevant to stakeholders in land-use management, policy and modelling. Despite recent progress in recognising such nexus challenges, most UK land-related policies and associated science continue to be compartmentalised by both scale and sector and seldom acknowledge nexus interconnections. On a temporal level, the absence of an over-arching strategy leaves inter-generational trade-offs poorly considered. Given the system lock-in and the lengthy policy-making process, it is essential to develop alternative ways of providing dynamic, flexible, practical and scientifically robust decision support for policy-makers. A range of ecosystem services need to be valued and integrated into a resilient land-use strategy, including the introduction of non-monetary, physical-unit constraints on the use of particular services. 相似文献
996.
A. F. Safonkin 《Russian Journal of Ecology》2000,31(3):203-206
The influence of food change on the development of the mothArchips podana was studied. Larvae of a natural population were collected from an apple tree. Nevertheless, the minimal duration of development
and the maximal weight of pupae in the next generation were observed in insects that developed on plum, pear, and currant,
rather than on apple trees. Transfer has effect on larvae of late instars: transfer from the plum to other trees results in
the deterioration of developmental parameters, while that from apple to plum and currant leads to their improvement. This
procedure has an effect on the proportion of pupating larvae. The timing of egg laying influences the development and mortality
of the larvae. The development of adults from older clutches on apple is comparable to that on plum. 相似文献
997.
The diet of juvenile trout and the state of their food resources in autumn (September–November) were studied in two typical small rivers tributary to Lake Onega (Karelia) in 2003. The relationship between the composition of food objects among benthic and drifting invertebrates and the food spectrum of trout was analyzed. The results show that before freeze-up, despite the disappearance of aerial and terrestrial insects, juveniles trout continue active feeding. However, their feeding priorities change: they begin to take food objects directly from the bottom, as well as from the water surface and within the water column. 相似文献
998.
硒的土壤生态环境、生物地球化学与食物链的研究现状 总被引:6,自引:0,他引:6
综述了硒的自然生态环境及全球土壤中硒含量与分布、形态及转化 ,决定植物硒含量及食物链系统中硒水平的关键因素 ,植物对硒的吸收和积累与遗传因子的关系 ,硒在植物组织中主要的存在形式 ,植物中硒的形态与生物有效性和生物利用率研究的意义 ,对食物链中的硒水平进行调控的方法及今后硒研究的前沿问题。 相似文献
999.
为掌握新疆石化企业的废水贮用现状,对新疆几个石化企业废水蓄水库运营状况及排水灌溉利用方式进行了调查分析。提出了石化企业废水冬贮及灌溉利用系统的未来管理重点和改进方向。并提出,解决新疆未来石化类工业园区排水出路问题时应注重技术进步,倡导循环经济和生态工业园区模式,因地制宜确定排水方案,应积极推进排水受纳区环境保护与资源化利用相结合的石化企业排水模式。 相似文献
1000.