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针对植物生理学课程考核中存在的弊端,探讨了多元化考核模式的建立,即参与过程考核、学习进程考核与综合知识考核相结合,并提出了多元化考核模式对教师的要求. 相似文献
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Integrated no-till crop and livestock production systems may help rejuvenate degraded pastures, increase land use efficiency (LUE), and increase enterprise revenue. Our objectives were to evaluate: (1) planting date effects on seed yield and nutrient concentration of an early-maturing, no-till system (NTS) soybean (Glycine max) when intercropped with palisade grass (Brachiaria brizantha); (2) dry matter production and protein concentration of the grass pasture after soybean harvest; and (3) overall revenue and LUE for the intercrop system. Experiments were performed during two growing seasons in Botucatu, Brazil using a randomized complete block experimental design. When palisade grass and soybean were sown simultaneously, soybean yield averaged 3.28 Mg ha−1. Similar seed yields were observed when palisade grass was planted either 30 d after soybean emergence (DAE) (3.29 Mg ha−1) or at the soybean reproductive stage R6 (full seed) (3.50 Mg ha−1). Monocrop soybean yield averaged 3.50 Mg ha−1. First cut dry matter forage production was greater when palisade grass was sown at the same time as soybean or 30 DAE of soybean. This indicates that interseeding palisade grass with soybean does not significantly affect soybean nutrition or yield. Intercropping did increase LUE and resulted in 1.6 times more revenue than soybean alone. However, sowing palisade grass at the soybean reproductive stage R6 (full seed) significantly reduced the forage yield compared to early planting. 相似文献
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本文基于企业多元化经营与绩效的相关理论,以2003 -2006年中国农业上市公司公布的年报面板数据为样本,利用多元回归模型和资本与劳动的产出弹性计算全要素生产率的方法,分析了农业上市公司多元化经营与绩效的关系,并对不同类型的多元化模式与公司的生产效率关系进行实证研究。结果表明,对于农业上市公司而言,企业总体多元化水平与业绩呈负相关,且与生产效率呈反方向变动关系。从各年静态对比看,横向多元化企业的生产效率高于纵向多元化企业的生产效率;从发展趋势看,从事横向多元化会降低企业的生产效率,而保持适度的纵向多元化会促进企业生产效率的提高。 相似文献
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通过对济南市泉城广场空间环境设计要点的详尽剖析,从整体的功能把握到周到的细部关怀,对如何塑造城市广场多元空间环境设计提出建议。 相似文献
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政府职能在以往的竞技体育发展中发挥着举足轻重的作用。体育的发展规律和体育核心价值是所有体育发展手段和路径的基础。竞技体育是体育发展的重要组成部分,在求同存异多元化发展的现代社会中,体育有必要更加持久地坚持多元化发展的大格局,但要与我国现实国情相结合,合理调整政府职能。以总体把握为主,适当鼓励和支持竞技体育可持续性的市场化发展和学校体教结合发展等多元模式的探索。 相似文献
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Concerns exist about the limited diversity of tree species in agricultural landscapes. Complete tree inventories were carried
out on 201 farms from four villages in western Kenya to establish whether significant differences in tree species composition
existed between farms, and if so their magnitude and implications for new introductions and plantings. Tree species composition
was interpreted to encompass elements of both tree identity and abundance. Tree identity was viewed from both taxonomic and
function (e.g. fruit, timber, medicine) perspectives. Novel types of ordination using the Hellinger ecological distance and
polynomial Redundancy Analysis indicated wide heterogeneity between farms with respect to tree species composition. For the
12 most prevalent functions of trees, the analyses showed significant differences (p<0.05). Partitioning of variance identified that village location explained much of the differences between farms suggesting
that farmers share tree species within villages more than between villages. Differences between farms were assessed on two-dimensional
ordination graphs. For five important tree functions, including beverage, charcoal, construction, fodder and medicine, two
species dominated the compositional differences. For these functions, diversification can be achieved by village-to-village
sharing even in the absence of any new species introductions. A general process to determine the degree of tree diversity
at farm and landscape levels and steps to increase it are discussed. 相似文献