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甘南牦牛发展现状及对策分析 总被引：1，自引：0，他引：1
1甘南自然地理概况甘南藏族自治州位于甘肃省西南部,地处青藏高原东部边缘,位于东经100°45′45″~104°45′30″,北纬33°06′30″~35°34′之间,是甘肃省乃至全国的主要牧区之一。全州海拔在1 172~4 920 m之间,平均海拔3 000 m,年平均气温在1.6~13.6℃,无绝对无霜期,年平均降水量约在550~800 mm之间。具有典型的大陆性气候特点,高寒阴湿,四季不分明。全州土地面积387.4万hm2,其中草地面积272.3万hm2,州内天然草场主要分布于夏河、碌曲、玛曲三县,草地类型主要有高山草甸、亚高山草甸、灌丛草甸、林间草甸、沼泽草甸、山地草甸。千百年来,… 相似文献
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以30份云南野生和逸生苜蓿(Medicago L.)资源为材料,对其分布区域气候、土壤特征及其生境进行系统研究,以探明云南野生和逸生苜蓿种群数量及适生性.结果表明:云南野生和逸生苜蓿资源在N 23°37′49.0”～28°34′09.1”,E98°47′31.4”～103°53′15.9”之间都有分布,垂直分布海拔范围为1122～2661 m;分布地年平降水量的变幅在300～1000mm,土壤含水量变化范围在0.79％～6.20％之间,土壤pH值变幅在4.30～8.37之间,采样地土壤较为贫瘠.分布地地貌类型多样,按其生境可分为杂草地型、干热河谷型、丘陵山地型和其他类型.苜蓿资源分布地优势植物和伴生植物共计18科45种植物,自然群落中的苜蓿主要作为伴生种零星存在;在迪庆州德钦县,德钦苜蓿作为优势种呈连片分布.综上所述,云南野生和逸生苜蓿资源在云南分布范围广,生境类型多样,具有较强的适生性和竞争能力,蕴含丰富的抗逆性苜蓿种质. 相似文献
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为了筛选出抗旱性较强的乡土草坪草种,在2010年6～9月期间利用盆栽试验研究了持续干旱胁迫对(落)草、羊茅与对照植物草地早熟禾种群的存活期、日均蒸腾量及其动态、萎蔫系数等指标的影响.结果表明:(1)在持续干旱胁迫下,与草地早熟禾相比,(落)草、羊茅种群总存活时间延长了18d～22d,出现暂时萎蔫症状时间推迟了14d～17d.(2)在植物发生暂时萎蔫之前,野生羊茅、(落)草种群的日均蒸腾量都显著低于草地早熟禾,二者的日均蒸腾量分别仅为草地早熟禾日均蒸腾量的60.44％、65.38％.(3)(落)草和羊茅种群发生暂时萎蔫、永久萎蔫时的土壤临界含水量均显著低于草地早熟禾,它们的平均最大土壤水分利用率为75.26％,也显著高于草地早熟禾.三种植物土壤水分最大利用率大小依次为:羊茅＞(落)草＞草地早熟禾. 相似文献
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草地螟(Loxosteges ticticalisL),是昆仑山天然草场的一种重要迁飞性害虫,探明昆仑山天然草场草地螟的越冬分布和生活史对其监测和防治工作具有重要意义。据2011～2012年观察结果表明:位于东经79°8′01″~81°07′63″,北纬36°06′33″~36°14′17″,海拔2718~3413m,范围为草地螟主要越冬分布区,其他区域为扩散越冬区。草地螟在昆仑山区一年发生一代,以老熟幼虫结茧越冬,翌年5月上旬茧内化蛹,5月下旬开始羽化,6月上旬进入盛期,6月中旬开始产卵,幼虫始见期为7月上旬,老熟幼虫8月初开始入土结茧越冬。 相似文献
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1 概况
尖扎县位于青海省东部,黄南藏族自治州的北部.地处东经101°37′43″～102°08′40″之间,北纬35°39′20″～36°10′00″之间,东西宽约48 km,南北长87 km,土地总面积1.714×10 hm2,境内地形山峦重叠、起伏连绵、沟脊相间.海拔1 960～4 614 m,气候属凉温、冷温半干旱气候区,年平均气温为8.6 ℃,年平均降水量为340～ ,全年日照时数为2 650～2 900 h,年总辐射量为151～155 kJ/cm2.全县拥有可利用草地面积1.266×10 hm2,占全县土面总面积的73.88%,可载畜17.49万个羊单位,平均每0.73 hm2草场养一只羊;疏林可利用面积2.4×10 hm2,可载畜1 934个羊单位;共计草场可利用面积1.29×105 hm2,可载畜17.68万个羊单位.尖扎县可分为6个草地类,分别是:山地草原类、山地草甸类、高寒草甸类、沼泽类、灌丛类、疏林类. 相似文献
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《畜牧兽医科技信息》2020,(8)
正为切实掌握草原狼毒防除后,草地产量和牧草群落结构变化状况,海北州草原工作站应用新型除草剂"灭狼毒"在海北州进行了效果试验,试验通过固定防除效果、产草量及牧草安全性和生物多样性等样方连续定位观测,为今后的防治工作提供了更加详实的科学依据。1材料与方法1.1试验区概况项目区位于海北州所属四县,地处东经98°05′25″～102°41′03″,北纬36°44′00″～39°05′18″,境内高 相似文献
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利用草地早熟禾改建江河源区“黑土型”退化草地的研究 总被引：11，自引：3，他引：8
利用正在驯化选育中的野生草地早熟禾,进行了“黑土型”退化草地植被改建试验,结果表明:在海拔4 000 m的地区野生和人工栽培条件下草地早熟禾种子均能成熟;具有较强的有性繁殖和无性繁殖能力,在栽培条件下能形成良好的草皮和植被覆盖度;草地早熟禾人工草地土壤总体含水能力增强,物理性状改善;地上植物量显著高于原生植被,达到了垂穗披碱草人工草地水平;实验室研究发现,草地早熟禾具有很强的抗寒性。可见草地早熟禾是三江源区“黑土型”退化草地植被改建的优良草种。 相似文献
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三江源区"黑土滩"退化草地的分类分级及治理模式 总被引：13，自引：2，他引：11
通过对三江源区120个野外调查样区的数据分析,依据地形条件以及工程的需要,将"黑土滩"退化草地划分为三种类型,即Ⅰ滩地:坡度在0.7°之间,Ⅱ缓坡地:坡度在≥7～25°之间,Ⅲ陡坡地:坡度≥25°.通过聚类分析和主成分分析,优选出秃斑地比例和可食牧草比例作为"黑土滩"退化草地分级的主要指标,将其分为轻度、中度和重度,并提出了相应的治理模式. 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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