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81.
Søltoft M Bysted A Madsen KH Mark AB Bügel SG Nielsen J Knuthsen P 《Journal of the science of food and agriculture》2011,91(4):767-775
BACKGROUND: The demand for organic food products has increased during the last decades due to their probable health effects, among others. A higher content of secondary metabolites such as carotenoids in organic food products has been claimed, though not documented, to contribute to increased health effects of organic foods. The aim was to study the impact of organic and conventional agricultural systems on the content of carotenoids in carrots and human diets. In addition, a human cross‐over study was performed, measuring the plasma status of carotenoids in humans consuming diets made from crops from these agricultural systems. RESULTS: The content of carotenoids in carrot roots and human diets was not significantly affected by the agricultural production system or year, despite differences in fertilisation strategy and levels. The plasma status of carotenoids increased significantly after consumption of the organic and conventional diets, but no systematic differences between the agricultural production systems were observed. CONCLUSION: The expected higher content of presumed health‐promoting carotenoids in organic food products was not documented in this study. Copyright © 2011 Society of Chemical Industry 相似文献
82.
甘蔗副产品综合利用与生态农业 总被引:1,自引:0,他引:1
本文从生态农业的原理出发,结合贵州甘蔗糖业发展的实际情况,甘蔗副产品综合利用与发展生态农业进行探讨。 相似文献
83.
近年来各类农业园区建设日益增多,本文试图通过具体案例对以产业为主的现代农业园区的规划进行剖析,主要从现状分析、规划设计和运行情况三方面进行论述,试图对这类园区的规划特点进行总结和提炼,以便从规划角度探索该类园区长远发展的规划模式。 相似文献
84.
A case study on the nutrient input-output budget of slash and burn agriculture was carried out in Northeast-Pará, Brazil, where such a land-use system has been practised for about 100 years. A common cropping period lasts for two years and the fields lie fallow for 4 to 8 years. We quantified rates of deposition, fertilization, and losses due to the burn, harvest and leaching. Six fields of different phases in the rotational cycle were under study during a 19 month period. During the fallow period, the input of Na, K, Mg, N, P and S via deposition exceeded the estimated losses with the seepage water. The Ca budget was almost balanced. The balance of fields in the transition from the fallow to the cropping phase was negative for Na, K, Ca, Mg, N, and S. The P balance was positive when NPK fertilizer was applied, and negative without fertilizer application. The nutrient balance for K, Mg, Ca, N, and P was also negative on the field in transition from the cropping to the fallow period. The nutrient budget for an entire land-use cycle of 9 years was estimated by the false time series approach. In the case of an NPK fertilization during the cropping period there were net losses of 75 kg K ha–1, 125 kg Ca ha–1, 16 kg Mg ha–1, 285 kg N ha–1 and 13 kg S ha–1. Na (86 kg ha–1) and P (11 kg ha–1) were accumulated. The harvest was the most important flux for the K (61%) and P (62%) output. The element transfer into the atmosphere during the burn caused the main losses of N (60%), S (65%), Ca (58%) and Mg (41%). The most important path of Na loss was leaching (92%). The net K losses were severe as they represented 45% of the K store found extractable in the soil down to 1m depth and in the above ground biomass. The presented results may be useful in planning a sustainable and environmentally protective method of land-use within a shifting cultivation system. It is strongly recommended that slash burning be abandoned in order to keep the nutrients in the ecosystem. 相似文献
85.
高吸水树脂的合成及在农业上的应用 总被引:6,自引:0,他引:6
介绍了近几年来高吸水树脂的合成研究成果和高吸水树脂在农业上的应用研究进展。近年来.涌现出许多新的高吸水树脂,尤其是一些高吸水树脂的耐盐性有较大提高,这对高吸水树脂在农业上的应用有极大的促进。本文也分析了高吸水树脂合成及在农业上的应用前景。 相似文献
86.
该文从地域化、生态化、人性化以及个性化的角度出发,探讨了江苏省连云港农电培训中心的建筑设计构思. 相似文献
87.
Ellen Burke 《Landscape Research》2018,43(5):587-599
Advocates of integrating food production landscapes within urban, suburban, campus and other design arenas cite multiple and integrated benefits, including enhanced food security and quality; land access for small farmers; psychological and social benefits; educational opportunities; and green infrastructure contributions, among others. If performance can be understood as ‘the fulfilment of a claim’ then landscape performance measures for food production would ideally encompass the overall range of cited benefits. Yet in current practice the performance of food production landscapes tends to be measured in limited ways, most often by weight and value of harvest. The aim of this paper is to identify expanded methods and metrics for measuring the performance of food production landscapes, in particular for health and well-being benefits. Through a transdisciplinary literature review, evidence for mental well-being, physical activity and human nutrition benefits of food production landscapes is presented, and performance metrics and evaluation methods are catalogued. 相似文献
88.
借鉴国外都市农业的经验,并结合我国国情,提出城市生态节地策略:打破城乡绝对分野、树立绿化新观念、开拓种植面积、构建都市农业生态循环系统,以零占地方案探讨生态节地策略的可行性。 相似文献
89.
便携式农田信息采集与管理系统的设计 总被引:1,自引:0,他引:1
为提高农田信息采集与存储的自动化水平,满足实时准确获取农田环境信息的需要,文章针对早期便携式农田信息采集仪记录与提取实时数据自动化程度低的问题,研制了一套便携式农田信息采集与管理系统。系统分为四个部分:(1)以嵌入式微控制器为核心部件;(2)以闪存控制器为数据存储单元;(3)以USB接口与计算机进行通信;(4)以数据库形式,对采集数据进行分类处理。该系统具有高性能、操作简单、扩展灵活等特点,对农业低成本自动化设备的更新改造具有重要的实用价值。 相似文献
90.