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11.
杨生民 《首都师范大学学报(社会科学版)》1996,(6)
本文根据商周时期4件青铜犁铧的大小、形制和夏商周时期石犁的大小,形制,及其他有关材料,探讨我国古代耕作方式的演变和牛耕的起源问题。 相似文献
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李清 《楚雄师范学院学报》2001,16(2):54-57
彝族经济社会发展不平衡,各地自然崇拜的对象、形式、内容各有侧重和变异,与各自的生产生活方式相适应,但有一个共同的特点,即自然崇拜明显地打上了稻作文化的烙印,反映的主题是彝族人民从旱作到稻作文化的转型、融合和重组,并最后形成了以稻作生产为中心的稻作祭祀链。 相似文献
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Getting a good and relevant education is difficult enough to achieve within a context where social and economic needs are constantly unsettled by political policy. The public funding of the education sector has become a contested arena irrespective of a government’s ideology. Recent graduates from various disciplines from Town Planning to Philosophy report in university destination surveys that they have only found employment in areas unrelated to their academic training – for instance, in supermarkets, restaurants and other low-level service industries. How has it happened that the universalisation of mass higher education has contributed to a disconnect between the individual’s social aspirations and their economic status? What happened to the tacit promise that an extended period of intellectual development would prepare the individual for a life of valuable social contribution and financial security? Part of the answer lies in the success of higher education itself. Its popularity has changed its transformative capacity and allowed operational efficiencies to overrule academic quality. The university, ideally seen as a repository of intellectual intuition, has been remade into yet another modern corporation concerned with the bottom line and financial security. Why has it been necessary to remake the university in the image of the department store, supermarket or bank, and how has it been achieved without more critique? 相似文献
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实现中、高职教育农科专业课程的有效衔接,是推动农科职业教育步入良性发展轨道的客观要求.本文对当前我国中、高等职业教育农科专业课程开发的现状进行分析,指出课程内容重复、专业技能倒挂等问题,并对建立中、高等职业教育农科专业课程的有效衔接机制进行阐述. 相似文献
16.
Tali Tal 《Environmental Education Research》2008,14(3):273-290
The last two decades have seen increased threats to agricultural landscapes in Israel. Key factors include population growth, strong pressure from construction entrepreneurs and possible profit to land owners who benefit from a legal conversion of farmland into lands allocated for construction. While each Israeli elementary school student used to participate in agriculture classes, most students no longer experience this and their overall exposure to farming in schools is limited. The main objective of this study was to explore the ways farming is presented and addressed in the national curriculum and in learning materials. Additionally, it examines the actual status of teaching about agriculture and explores how farming is addressed in teachers' pre‐service programmes. The main finding is that very little teaching about agriculture and land management is carried out at most school levels. Only one college prepares agriculture teachers and science education programmes rarely address agriculture as a course topic. The paper also outlines an education for sustainability framework for integrating science, agriculture and environmental education. 相似文献
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Measurement and analysis of soil nitrogen and organic matter content using near-infrared spectroscopy techniques 总被引:2,自引:0,他引:2
Near infrared reflectance (N1R) spectroscopy is as a rapid, convenient and simple nondestructive technique useful for quantifying several soil properties. This method was used to estimate nitrogen (N) and organic matter (OM) content in a soil of Zhejiang Province, Hangzhou County. A total of 125 soil samples were taken from the field. Ninety-five samples spectra were used during the calibration and cross validation stage. Thirty samples spectra were used to predict N and OM concentration. NIR spectra of these samples were correlated using partial least square regression. The regression coefficients between measured and predicted values of N and OM was 0.92 and 0.93, and SEP (standard error of prediction) were 3.28 and 0.06, respectively, which showed that NIR method had potential to accurately predict these constituents in this soil. The results showed that NIR spectroscopy could be a good tool for precision farming application. 相似文献
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萧云岭 《淮南师范学院学报》2006,8(6):84-85
屯田制是中国传统社会用军事管理方式将劳动者束缚于国有土地上的一项特殊的土地制度。曹魏在特殊的历史时期,实行了这项特殊的制度,其军事编制的组织形式,自成体系的管理体制体现了效率与效益的有机结合;国民两便的分配机制和屯田所带动的水利基础设施建设,都具有创新的成分。 相似文献
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农业生产环节外包是实现农业规模经济的重要途径。依据山东、河南2省6市小麦种植户调研数据,运用结构方程模型实证分析农户农地禀赋效应调节视角下外包交易成本、农业隐性生产成本对农业生产环节外包程度的影响。研究结论如下:①市场容量、资产专用性、交易不确定性和交易频率是外包交易成本的重要表现。市场容量的扩大可以降低单位面积外包交易成本,促进农业生产环节外包程度的提升;资产专用性、交易不确定性和交易频率的增强会增加外包交易成本,阻碍农业生产环节外包程度的提升。②农业生产经营风险和农业劳动机会成本是隐性生产成本的重要体现,二者均会促进农业生产环节外包程度的提升。③外包交易成本、隐性生产成本对农业生产环节外包程度的影响会受到农户农地禀赋效应的调节。在外包交易成本方面,农户农地禀赋效应会削弱市场容量对农业生产环节外包程度的促进作用,增强资产专用性和交易不确定性对农业生产环节外包程度的阻碍作用;在隐性生产成本方面,农户农地禀赋效应会增强农业生产经营风险对农业生产环节外包程度的促进作用,削弱农业劳动机会成本对农业生产环节外包程度的促进作用。④农业外包市场并不仅是一个简单的交易市场,而且是一个具有身份特征的情感市场。培育农业外包市场,需充分考虑和尊重农户的农地禀赋效应。 相似文献