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根据草地和农牧交错区生态系统重建机理及优化生态—生产模式国家重点基础研究发展规划的要求,综合分析了我国农牧交错区的基本现状,系统论述了农牧交错区存在的草地"三化"突出、农业生产低下、自然灾害频繁、人民生活贫困等问题,研究和寻求生态系统退化、恢复和重建的关键技术与途径,进一步探讨在西部大开发中农牧交错区的发展思路。 相似文献
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农牧交错区草地农业系统理论与实践的探讨 总被引：1，自引：1，他引：0
分析了中国农牧交错区生态环境恶化的原因及后果.环境的恶化尤其是水土流失与土壤荒漠化是导致该区贫瘠与灾害的主要根源,而生态环境恶化的主要原因是综合治理与经济发展的长期失调.依据农牧交错区自然生境特点及资源优势,结合前人在该区开发治理的经验和发展草地农业试点的成果,草地农业系统应在农牧交错区开发治理中起主导作用.大力发展草地农业是农牧交错区农业可持续发展的有效途径,阐述了草地农业在农牧交错区生态环境治理与农业经济持续发展中的作用和发展模式. 相似文献
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《黑龙江畜牧兽医》2020,(11)
为了解蒙(内蒙古)辽(辽宁)农牧交错区草地资源植物概况,以内蒙古自治区与辽宁省交界处17个半农半牧县的草地为研究区域,采用野外样点调查与统计分析相结合的方法,确定研究区域主要草地资源植物类型,并分析蒙辽农牧交错区草地生态系统资源植物的种群分布特征和开发利用现状。结果表明:蒙辽农牧交错区有118种草地资源植物,隶属32科88属,药用资源植物85种,占总资源植物的72.03%;食用资源植物22种,占18.64%;工业用资源植物20种,占16.95%;防护和改造环境的资源植物14种,占11.86%。说明蒙辽农牧交错区药用资源植物和食用资源植物丰富,其中科尔沁左翼后旗、库伦旗和阜新市草地资源植物类型齐全,种类最为丰富。 相似文献
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北方农牧交错区草地生态系统服务间接价值的初步评估——以太仆寺旗和沽源县境内为例 总被引：3，自引：1，他引：2
以草地地上生物量为基础,运用经济学的市场价值法、物质量法、水量平衡法等方法对太仆寺旗和沽源县境内的农牧交错区草地的固定CO2、释放O2、土壤侵蚀控制、涵养水源、营养物质循环5项生态系统服务功能进行初步的评估。结果表明：由这5项功能构成的生态系统服务的间接价值在农区为16 668元/（hm2·a）,在草原区为17 223元/（hm2·a）。尽管草原区的间接价值比农区的高3.33%,但研究所选的农牧交错区由于农业活动的干扰,并没有导致草地生态系统服务功能间接价值的显著下降。这说明维持现阶段的农业活动或退耕还草可能促进草地生态系统生态经济价值的可持续性发展;但若继续开垦和破坏草地,草地生态系统的服务功能可能会显著下降,草地所具有的生态屏障作用也会减弱甚至消失。 相似文献
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草地-农田界面是我国北方农牧交错带的重要景观组成部分,具有复杂的生态系统结构、功能和生态过程,对自然因素及人为干扰十分敏感。以松嫩平原大庆市林甸县农牧交错区草地-农田界面为对象,分别向草地和农田延伸50 m,采用多元回归分析、主成分分析等方法对表层(0～20 cm)土壤养分、酶活性指标进行了空间分布变化分析和综合评价。结果表明：土壤养分含量及酶活性各指标在农牧交错区草地-农田界面上存在明显的空间异质性。土壤有机质、碱解氮、速效钾、速效磷等指标在草地高于农田。土壤pH值、含水量、全氮、全磷、全钾含量、土壤过氧化氢酶、脲酶活性等指标在界面0点附近变化剧烈,显著高于草地内部和农田内部(P<0.05),表现出明显的界面效应。相关性分析和主成分分析表明,土壤酶活性和土壤性质密切相关,其中土壤pH值与土壤酶活性呈极显著正相关,有机质和速效养分与土壤酶活性呈极显著负相关(P<0.01)。研究结果丰富了北方农牧交错带草地-农田界面的理论基础,为松嫩平原农牧交错区草地与农田过渡区的合理利用提供了理论依据。 相似文献
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正北方农牧交错区带是年降水量在350~550毫米,地理景观以农田生态系统、草原生态系统交错镶嵌分布,农业生产经济发展以畜牧业和种植业并重的区域。与北方草原纯牧区相比,农牧交错区带自然条件相对优越,降水比较丰沛,热量条件良好,能够从事农业生产,所以农牧交错带农业和草原畜牧业可以相辅相成、发展现代草食畜 相似文献
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按照农牧交错区草地资源可持续利用评价原则对初级指标群进行评分,用AHP法建立比较判断矩阵,通过数学运算计算出各层指标与目标层指标相对优劣的排序权值,运用模糊数学的隶属度函数,计算出最终评定结果,以此对农牧交错地区不同地域草地资源可持续利用状况进行综合评判,同时评价农牧交错区经济社会发展模式在多大程度上反映科学发展观的要求。 相似文献
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农牧交错区草地资源可持续利用定量研究 总被引：1，自引：0，他引：1
按照农牧交错区草地资源可持续利用评价原则对初级指标群进行评分，用AHP法建立比较判断矩阵，通过数学运算计算出各层指标与目标层指标相对优劣的排序权值，运用模糊数学的隶属度函数，计算出最终评定结果，以此对农牧交错地区不同地域草地资源可持续利用状况进行综合评判，同时评价农牧交错区经济社会发展模式在多大程度上反映科学发展观的要求。 相似文献
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Beran GW 《Preventive veterinary medicine》2008,86(3-4):198-207
When early people made their appearance, zoonotic infectious diseases were already waiting, but epidemic diseases did not appear in human history until people began to live in large numbers under conditions of close contact, mainly during the last 10,000 years. Disease has decimated urban populations, conquered armies, and disrupted society. The focus here is on (1) the plague of Athens and the Black Death; (2) smallpox, influenza, and rabies; (3) avian influenza prion diseases, and foot & mouth disease; and (4) emerging and re-emerging diseases. All have veterinary public health associations. In Athens, Greece, in 430 BC, when the Spartans ravaged the countryside, hordes crowded into Athens so that orderly movements, space in which to live, and adequate supplies of food became impossible. Crowding of any population fosters disease transmission; chaos and disorder enhance it all the more. Out of northern Egypt came a terrible plague from across the Mediterranean Sea. The identity of the plague of Athens remains unsure, but the well-considered conclusion is Rift Valley Fever, a mosquito borne, viral zoonosis. The Black Death, also called the Plague, raged in Asia for centuries. In 1347, the Black Death was brought by a ship out of Asia to Sicily. The scenes of devastation were repeated throughout Europe, with 90% or more of the people dying in city after city. Influenza, too, has been a cause of periodic human epidemics, but the great pandemic of influenza occurred in the last months of World War I. In the years of highest occurrence, more than half the world's population became clinically infected. If veterinary public health had been born earlier, it could have led to elucidating the epidemiology of influenza and the plagues of Athens, Europe, and Asia. In turn, smallpox had also caused continual tragedy. In 1796, Edward Jenner began to harvest pustules of cowpox from children or infected cows and inject them into susceptible children. In 1980, the World Health Organization declared that smallpox had been eliminated from the world. Rabies, though, still strikes terror. A number of animal diseases, broadly termed emerging and re-emerging diseases, need surveillance because they have the potential to impact human health. From late in 2003 to 2007, the highly pathogenic H5N1 influenza virus in poultry infected at least 121 people and caused 62 deaths in four countries. The prion diseases, too, all have very high numbers in concentrated contacts. To control these diseases, veterinary public health is essential, with diagnosis, epidemiological surveillance, clinical manifestations, and prevention as primary measures. 相似文献
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Dekker A Dercksen D Snoep J van Wuyjckhuise L 《Tijdschrift voor diergeneeskunde》2007,132(18):695-701
On 26th of july 2007 a new case of bluetongue was notified in the Netherlands and on 2nd of august 2007 foot-and-mouth disease was diagnosed in Surrey, England, which raised the threat of having both infections simultaniously in one area. Bluetongue and foot-and-mouth disease have a different pathogenesis, but symptoms may resemble each other at a later stage of infection. The pathogenesis and possible clinical symptoms of both infections are discussed and illustrated with pictures. 相似文献
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在动物的异常行为中以刻板行为最为常见,而咽气癖又是马最常见的口部刻板行为之一。作者就咽气癖在生理方面和心智方面对马体产生的影响、行为基础、诱因的研究进展及常见的防治措施进行综述。 相似文献
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