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941.
Superior species may have distinct advantages over subordinates within asymmetrical interactions among sympatric animals. However, exactly how the subordinate species coexists with superior species is unknown. In the forests west of Beijing City, intense asymmetrical interactions of food competition exist among granivorous rodents (e.g. Apodemus peninsulae, Niviventer confucianus, Sciurotamias davidianus and Tscherskia triton) that have broadly overlapping habitats and diets but have varied body size (range 15–300 g), hoarding habits (scatter vs larder) and/or daily rhythm (diurnal vs nocturnal). The smallest rodent, A. peninsulae, which typically faces high competitive pressure from larger rodents, is an ideal model to explore how subordinate species coexist with superior species. Under semi‐natural enclosure conditions, we tested responses of seed‐hoarding behavior in A. peninsulae to intraspecific and interspecific competitors in the situations of pre‐competition (without competitor), competition (with competitor) and post‐competition (competitor removed). The results showed that for A. peninsulae, the intensity of larder‐hoarding increased and the intensity of scatter‐hoarding declined in the presence of intraspecifics and S. davidianus, whereas A. peninsulae ceased foraging and hoarding in the presence of N. confucianus and T. triton. A. peninsulae reduced intensity of hoarding outside the nest and moved more seeds into the nest for larder‐hoarding under competition from intraspecific individuals and S. davidianus. In most cases, the experimental animals could recover to their original state of pre‐competition when competitors were removed. These results suggest that subordinate species contextually regulate their food‐hoarding strategies according to different competitors, promoting species coexistence among sympatric animals that have asymmetrical food competition.  相似文献   
942.
从采用灵活多变的教学手段、自行设计实验内容、强化实验操作技能和养成实验操作习惯等方面,提出如何提高食品微生物学实验课的教学质量,培养学生动手能力、独立思考解决问题的能力、创新能力。  相似文献   
943.
随着我国人民生活水平的提升,休闲食品逐渐成为人们的日常消费品之一。休闲食品 是人们在休闲期间食用的快速消费品,消费者购买食品主要的目的是为了体验美味、享受时光、 放松心情。如何提高消费者在休闲食品店的体验感,将关系到休闲食品店的销售额和利润额,作 者通过对安徽乐大嘴零售公园的分析研究,认为可以休闲食品店可以从产品体验、感官体验、价 格体验、情感体验和环境体验。  相似文献   
944.
Water scarcity in agriculture is becoming a major problem due to increasing demand from nonagricultural uses and intensive crop management on existing croplands to meet the needs of an expanding global population. Efficient use of the available irrigation water is therefore of important concern. Even though intensive research in the areas of crop physiology, irrigation engineering, agronomy and agricultural economics has developed several ways to improve the efficiency of irrigation water, a multidisciplinary approach is often regarded as the best future path to achieve further enhancements in meeting the forthcoming challenge of producing more and safety foods. Failure of irrigation production has profound effects on the welfare of all those employed in it and also their customers. Indeed, the scale of the industry is such that world food prices will be influenced by the overall performance of the irrigation farmers, but low food prices are essential to the welfare of the poorest people. The contribution of irrigation and water management to increased food production must come through both expansion of irrigation and improved management of existing water supplies. This review presents the past, current and future panorama of irrigation as a viable tool in ensuring food security on the globe. Considering past trends, this review empathizes that future irrigation technologies should be focused on providing the leadership and capacity to capture, develop and promote new irrigation practices and management systems to optimize production.  相似文献   
945.
播期对鲜食花生经济效益的影响   总被引:2,自引:0,他引:2  
许卫平  段莹  张建立  许巧  于乐琴 《安徽农业科学》2006,34(19):4899-4899,4901
选用早熟花生品种远杂9102进行鲜食花生的播期试验,结果表明,不同时期播种,花生的产量和经济效益不同。  相似文献   
946.
Nutraceuticals have gained immense importance in poultry science recently considering the nutritional and beneficial health effects of their constituents. Besides providing nutritional requirements to birds, nutraceuticals have beneficial pharmacological effects, for example, they help in establishing normal physiological health status, prevent diseases and thereby improve production performance. Nutraceuticals include amino acids, vitamins, minerals, enzymes, etc. which are important for preventing oxidative stress, regulating the immune response and maintaining normal physiological, biochemical and homeostatic mechanisms. Nutraceuticals help in supplying nutrients in balanced amounts for supporting the optimal growth performance in modern poultry flocks, and as a dietary supplement can reduce the use of antibiotics. The application of antibiotic growth enhancers in poultry leads to the propagation of antibiotic-resistant microbes and drug residues; therefore, they have been restricted in many countries. Thus, there is a demand for natural feed additives that lead to the same growth enhancement without affecting the health. Nutraceuticals substances have an essential role in the development of the animals’ normal physiological functions and in protecting them against infectious diseases. In this review, the uses of amino acids, vitamins and minerals as well as their mode of action in growth promotion and elevation of immune system are discussed.  相似文献   
947.
Genotypic variation in grain cadmium concentration of lowland rice   总被引:6,自引:0,他引:6  
Cadmium (Cd) contamination of paddy rice soils is commonly observed in the Yangtse River Delta, China. Large Cd uptake by rice plants and its translocation into the grains can entail human‐health risks. Genotypic variations in Cd uptake and a differential Cd partitioning into grains will be the basis for developing a rice screening or breeding tool for low grain Cd. A field experiment, conducted at the experimental farm of Jiaxing, Zhejiang province from 2002 to 2004, compared 38 rice genotypes of different types (indica vs. japonica) collected from the Yangtse River Delta. The results showed large differences in Cd concentrations in straw, brown rice, and grain chaff among the rice genotypes grown on Cd‐contaminated soil. Concentrations in brown rice ranged from 0.06 to 0.99 mg Cd kg–1. The total Cd uptake in brown rice varied between 0.96 and 28.58 μg plant1. In general, indica‐type cultivars accumulated significantly more Cd than the japonica‐type cultivars. The Cd concentration in straw was highly correlated with that in brown rice. While significant differences in the Cd‐partitioning ratio (% share of total Cd uptake found in brown rice) among rice genotypes were observed, these were not correlated with Cd concentration of brown rice. This indicates that the Cd accumulation in rice grains appears to be governed mainly by the Cd uptake by the plant and probably not by differential Cd partitioning. The large genotypic variation suggests the possibility to lower the Cd content of rice by genotype selection. The development of such breeding tools should focus on low Cd uptake rather than Cd partitioning between straw and grain.  相似文献   
948.
双孢蘑菇绿色食品标准化栽培技术   总被引:5,自引:0,他引:5  
结合农业科技标准化项目进行蘑菇绿色食品生产模式的栽培研究,从绿色食品蘑菇的栽培环境、栽培基质选择、栽培期管理、病虫害防治,以及采收、包装、贮运等主要环节提出双孢蘑菇绿色食品标准化栽培技术。  相似文献   
949.
对食品科学与工程类本科生实践教学环节的改革进行研究和探索,分析了该类专业实践教学现状及存在的问题,并根据该专业的特点和卓越农林人才的培养标准,建立一个较为完整的实践教学体系,明确该体系的运行方式,以期通过实施该体系培养出卓越农林人才.  相似文献   
950.
This paper focuses on examining the dynamic nature of community supported agriculture (CSA) and the real-world experiences which mark its contours, often making it distinct from the early idealized CSA “model.” Specifically, our study examines the narratives of the farmers of Devon Acres CSA over its duration, in tandem with a survey of recent shareholders in order to understand and explain its evolution. The framework we develop here shows that this CSA is largely characterized by instrumental and functional beliefs and practices, with some elements in the collaborative mode. A key contribution of this research is the development of a framework which helps to highlight the relative fluidity and patchwork quality of CSA participant positions over time. At Devon Acres, the real-world factors and issues influencing CSA evolution are seen to be products of both the local and larger contexts, evident in such areas as shifts in farmer learning and adaptation, differences between beliefs and practices in member volunteer efforts, and changes in farm and resource conditions. With respect to CSA more broadly, we argue that the reality of dominant food system context and site-specific influences on CSA development compels us to rework our attachment to early idealized “model” traits. Expansion in CSA numbers, evidence of adaptation and situated learning, and retention of the local and organic as core traits, speak to the pragmatic yet transformative potential of CSA contribution to food system change.
Robert FeaganEmail:

Robert Feagan   PhD, is a faculty member in the interdisciplinary Contemporary Studies Program at the Brantford Campus of Wilfrid Laurier University in Ontario, Canada. His research and teaching interests are in local and regional food systems—farmers’ markets, CSAs, etc., in university–community partnerships, in community development, and in the green-burial movement. Ideas and objectives of “sustainability” underlie his many research directions. Amanda Henderson   earned a Masters Degree from the Faculty of Environmental Studies at York University in Toronto. She lives and works on a communal eco-farm in rural Ontario, Canada.  相似文献   
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