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中国家驴的母系起源与遗传多样性研究
作者: 葛庆兰   来源: 西北农林科技大学 年份: 2007 文献类型 : 学位论文 关键词: 线粒体DNA   母系起源   遗传多样性   中国家驴  
描述: 为了研究中国家驴的起源进化与遗传多样性,本研究利用线粒体DNA(mtDNA) D-loop序列分析方法对我国12个家驴品种126个个体进行分析,这些家驴品种为泌阳驴、德州驴、关中驴、淮北灰驴、佳米驴、蒙古驴、凉州驴、庆阳驴、太行驴、西吉驴、新疆驴和云南驴。通过数据分析本研究所得出的主要结论如下: (
全文:、蒙古驴、凉州驴、庆阳驴、太行驴、西吉驴、新疆驴和云南驴。通过数据分析本研究所得出的主要结论如下: (1)中国家驴具有丰富的遗传多样性。在所分析的12个家驴品种126条序列中,共发现36种单倍型,37
古代游记的农史价值研究
作者: 徐臣攀   来源: 西北农林科技大学 年份: 2007 文献类型 : 学位论文 关键词: 畜牧及渔业   林木与花卉   种植业   农业环境   古代游记  
描述: 论文对游记的概念进行了界定、对其起源与发展情况作了探究。认为游记是介于历史与文学之间的一种文体,其以记实、准确为基础,又不乏感情的流露;古代游记起源于先秦、形成于秦汉、晋魏南北朝、发展于隋唐五代、宋、元并且繁荣于明清;它反映的地域极为广泛,就国内来说西至西域诸国,东南可达南海地区;游记中大量有关自然
全文:类、文学类游记中的涉农资料较为少见;游记农事资料总体上讲具有真实性、地域性、时段性、多样性和零散性等特征。 本文对游记中的农业史料进行了分类整理,并且就游记资料在研究农业生产环境、种植业、林木与花卉
历史时期青海地区自然灾害与区域社会经济发展研究
作者: 刘雯   来源: 西北农林科技大学 年份: 2009 文献类型 : 学位论文 关键词: 青海地区   自然灾害   历史时期   社会效应  
描述: e distinctive features in Western and Eastern of Qinghai's natural disaster in history which based on the historical materials and studied the Interaction Relationship Between the natural disasters and social-economic development, we used the theory and analysis method from the research area of disaster history and agricultural history, try to have a comprehensive investigation between the natural disasters and social-economic development in the history of Qinghai. Firstly, we divided Qinghai into two parts: the eastern and the western, under the study of the geographical features of Qinghai. We summarized the natural disaster of the eastern part mainly as flood, drought, hailstone and frost with distinctive features of variety, continuity and growth accompany while the western is mainly as earthquake and snow disaster with distinctive features of unexpected and severity. Secondly , as the great influence on agriculture and the resulting changement in agriculture is most profound, so the progress in agriculture sciences is related to withstand the natural disaster in some ways. The paper discussed the natural disasters affected Qinghai's agriculture in history, from the aspect of seed selection 、 production 、 processing and storage to invest the development of mitigation techniques in this area. And for the livestock we investigated in two sides bred of livestock and prevention of livestock, furthermore we invested the mitigation techniques which full of geographical characteristics. Thirdly, the article investigated the relationship between natural disasters and the economic fluctuation in Qinghai from the perspective of the change in population and grain price. And then, we analyzed the influence on regional industrial structure from the aspect of expansion in rural areas, the relationship between agriculture and animal husbandry, disaster-relief crop introduction and the structure of animal species. In the view of pastoral economic exchange, we studied the interaction relationship between the natural disasters and economic development. Finally, we studied the interaction relationship between the natural disasters and social development in Qinghai. What is more, we analyzed the policy which includes grain storage, relieved and help the people in disaster , reduced taxes to control the disaster in history. We wish these could be helpful to the prevention and control of natural disasters in Qinghai today.
全文:为主的自然灾害存在着多样性、增长性、连续性、伴生性的特点;青海西部以地震、雪灾为主的自然灾害则更具突发性和严重性。 其次,由于农业在自然灾害中所受影响最大,由此带来的一系列改变也最为深刻,农业科技的进步
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