关键词
厚皮甜瓜耗水规律与调亏灌溉效应研究
作者: 高慧娟   来源: 甘肃农业大学 年份: 2010 文献类型 : 学位论文 关键词: 光合特性   产量   调亏灌溉   耗水规律   水分利用效率   甜瓜  
描述: conducted full irrigation (CK), mild regulated deficit irrigation and moderate regulated deficit irrigation with melon varieties of Ymdi and Yujinxiang in three growth stages including sowing to flowering time, flowering to fruit expanding stage and fruit expanding to picking time.
全文:本试验于2009年4月~2009年8月在甘肃民勤县农技中心试验站进行,以银帝和玉金香为试验材料,在甜瓜的播种-开花期、开花-膨大和膨大-采收分别设置充分灌溉(对照)、轻度调亏灌溉和中度调亏灌溉
甘肃中东部旱作农业区气候变化特征及其对农业生产的影响
作者: 刘艳艳   来源: 西北师范大学 年份: 2010 文献类型 : 学位论文 关键词: 农业生产   气候变化   生育期   甘肃中东部旱作农业区  
描述: ogical characteristics of the crops and people’s production and business activities, largely dominated by light, heat, water, gas and other climatic factors.
全文:引起的。(6)2000年后与1980s相比,观测区春小麦乳熟推迟,其他各生育均提前,播种、出苗期、拔节、抽穗、成熟分别提前1~2d、2~3d、2~7d、2~4d和6~7d,春小麦全生育
隋唐时期青海草原战争与生态环境研究
作者: 来霞霞   来源: 陕西师范大学 年份: 2010 文献类型 : 学位论文 关键词: 生态环境   吐谷浑   吐蕃   青海草原  
描述: t Territories distributed a few mature Minority forces,for example: TuYuhun, Tibet, Party items.
全文:模式的西部开发都是粗放型方式,尽管其军事和政治意义重大,但经济和环境意义却难以一言以蔽之,如与气候变化相叠加,很容易出现生态环境退化的。且军事活动对于自然环境和与之相关的农业生产造成的反作用,大多是
隋唐时期青海草原战争与生态环境研究
作者: 来霞霞   来源: 陕西师范大学 年份: 2010 文献类型 : 学位论文 关键词: 生态环境   吐谷浑   吐蕃   青海草原  
描述: t Territories distributed a few mature Minority forces,for example: TuYuhun, Tibet, Party items.
全文:模式的西部开发都是粗放型方式,尽管其军事和政治意义重大,但经济和环境意义却难以一言以蔽之,如与气候变化相叠加,很容易出现生态环境退化的。且军事活动对于自然环境和与之相关的农业生产造成的反作用,大多是
明清时期中外农业科技文化交流研究
作者: 刘玉静   来源: 西北农林科技大学 年份: 2010 文献类型 : 学位论文 关键词: 科技文化   农业   交流   明清时期  
描述: ry of agricultural development in China has a special significance. China introduced some of the new species, new technology and new knowledge from the West to transform traditional agriculture and improve production efficiency.
全文:明清时期在中国农业发展史上具有特殊之地位与影响。一方面,这一时我国传统农业科学技术发展到了完全成熟的阶段,农学著作要超过之前所有农学著作的总和,农学思想也日臻完善。另一方面,这一时也是中国传统
明清时期中外农业科技文化交流研究
作者: 刘玉静   来源: 西北农林科技大学 年份: 2010 文献类型 : 学位论文 关键词: 科技文化   农业   交流   明清时期  
描述: ry of agricultural development in China has a special significance. China introduced some of the new species, new technology and new knowledge from the West to transform traditional agriculture and improve production efficiency.
全文:明清时期在中国农业发展史上具有特殊之地位与影响。一方面,这一时我国传统农业科学技术发展到了完全成熟的阶段,农学著作要超过之前所有农学著作的总和,农学思想也日臻完善。另一方面,这一时也是中国传统
明清时期石羊河流域农业开发与环境变化研究
作者: 栾晓丽   来源: 陕西师范大学 年份: 2010 文献类型 : 学位论文 关键词: 石羊河流域   农业开发   明清时期   环境变化  
描述: In history;the central and local separatist all valued the development of this area. During the Ming and Qing Dynasties,with the renewed fighting in the northwest, coupled with the rapid growth of the national population, In order to consolidating border defense and detenting Mainland population pressure,the land development of this area resumevted,which impacted histoy development of this area very profoundly Academic research in this area is more included in the academic research for the whole Hexi area or the entire northwest region, special articles in this area are also mainly concentrated in the lower reaches of Shiyang River, but these research the upper, middle and lower reaches of the river as a whole rarely,the connection among the three is.very close essentially.So this object has larger space to continue researching. This text includes introduction and body text.the introduction introduces the writing causes ,implication,and retrospects intellectual history, explains research objectives,Methods and important and difficult points of this object at the same time.The body text divides into six chapters.The first chapter analyzes the natural conditions and social infrastructure in this area.The second chapter mainly deals with immigration status which Ming and Qing government organize and encourage the population in the mainland move to this area,which provides manpower resources for agricultural development in this area,and this chapter discusses effectiveness of the immigration.The third chapter discusses construction of water conservancy which agricultural development requires,and summarizes pearls and pitfalls of water conservancy construction in this area during this period.The fourth chapter mainly deals with agricultural development in this area during the Ming and Qing dynasties,This chapter begin by the reasons for agricultural development and policies which the government urge and offer for, discusses region of agricultural development, reclamation success and evolution of tonden in this area during this time.The fifth chapter mainly discusses environmental problems that because of large-scale development in this period,and analyzes performance, hazard and measures that local people inoder to protecting the environment had taken.The sixth chapter summarizes experience and lessons those because of large-scale development in this period during this time,and explains inspiration for today's development. Research of this object is primarily based on literature of the Ming and Qing Dynasties and local records, and notes data that through field visits get, in order to make the discussion Speci.ficly and reasonably.
全文:位于河西走廊东部的石羊河流域是河西三大内陆河流域之一,其军事地理位置重要,历代中央王朝和割据于此的地方势力都十分重视对本区的开发。明清时期,随着西北战事再起,加上这一时全国人口数量的急剧增长,为了
新疆棉花“订单农业+期货”模型的构建与实证研究
作者: 徐春华   来源: 石河子大学 年份: 2010 文献类型 : 学位论文 关键词: 最小方差套期保值   传统套期保值   价格发现   棉花期货   订单农业  
描述: nd its ability to resist the risk of price fluctuation is fluctuating in relatively weak, so they often become the most direct victims for the rapidly cotton price, reducing the cotton farmers'enthusiasm to grow cotton .The cotton
全文:的“小农户”、流通企业、加工企业等各自分散的状态,订单农业这种组织模式正好可以将它们连接起来,构成共同利益体。期货市场的价格发现功能和套保值功能能够为签订订单农业提供价格参考和转移订单价格风险,降低不
石羊河流域作物气候生产潜力及灌溉对策的研究
作者: 孙世坤   来源: 西北农林科技大学 年份: 2010 文献类型 : 学位论文 关键词: GIS   气候生产潜力   灌溉需水量   对策   CROPWAT  
描述: be given when fully and rational use of local climatic resources such as solar radiation, heat and water, while other conditions (such as soil fertility, carbon dioxide concentration, cultivation level etc.)
全文:提高。 (5)针对石羊河流域光合、光温和气候生产潜力的分析,认为可以从以下几方面提高流域气候资源利用率,进而提高现实产量。1)加强农田水利建设,保障作物生育灌溉用水;2)选用和培育适宜的作物品种;3)提高作物降水生产潜力;4)充分利用土地自然资源,提高复种指数;5)发展设施农业。
明清及民国时期黑河流域中游地区绿洲化荒漠化时空过程研究
作者: 石亮   来源: 兰州大学 年份: 2010 文献类型 : 学位论文 关键词: 干旱区   黑河流域   明清及民国时期   绿洲化与荒漠化时空过程  
描述: had been also analyzed. The results showed that: 1. In the early Ming Dynasty, the study area had
全文:化荒漠化过程作为研究对象,综合运用历史地理学、遥感、地理信息系统等研究方法,在遥感影像的基础上,定量地重建了这一时黑河流域中游地区绿洲的范围和面积,分析了古绿洲开发与荒漠化的时空过程。主要结论包括
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