Overland flow resistance and its components for slope surfaces covered with gravel and grass     

《国际水土保持研究(英文)》2022,10(2):273-283

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高寒区不同豇豆品种生长特性及饲用品质研究          下载免费PDF全文

冯钰  邢宝龙 《作物杂志》2022,38(6):220-49

为筛选出适宜高寒区种植的优质豇豆品种，探究了山西大同高寒区9个豇豆品种的生长特性及饲草品质。结果表明，9个豇豆品种在试验地均能完成生育过程，且作为饲草种植最佳收获期为结荚期。其中以品豇dt2018-5、JD-01和品豇dt2018-9这3个品种表现良好，干物质含量分别为31.9%、35.2%和32.6%，粗蛋白含量分别为22.4%、25.5%和24.2%，粗脂肪含量分别为1.7%、1.4%和1.6%，酸性洗涤纤维含量分别为21.5%、21.2%和24.6%，中性洗涤纤维含量分别为24.5%、27.6%和31.2%，干草产量分别为496、352和325kg/hm²，鲜草产量分别为2661、2241和2132kg/hm²。故品豇dt2018-5、JD-01和品豇dt2018-9可作为推广品种。  相似文献   

Evaluation of Eucalyptus Camaldulensis (river GUM) and Chamaecytisus Proliferu (Tagasaste) for salinity control by agroforestry     

J. Eastham  P. R. Scott  R. A. Steckis 《Land Degradation \u0026amp; Development》1993,4(3):113-122

Components of the soil water balance were measured over a three year period for Eucalyptus camaldulenis and Chamaecytisus proliferus, species commonly used for revegetation in Western Australia, and compared with water balance components for pasture. Marked seasonal trends in evapotranspiration were observed for all species with maxima occurring in the wet months, and minima occurring in summer when rainfall was low and evaporative demand high. in each year of study, annual evapotranspiration and soil water depletions were greater for both tree species than for the pasture, due to the greater extraction of soil water at depth. Upward movement of water from the saturated zone was also found to be greater beneath the deeper rooted perennials than beneath pasture.  相似文献   

稻草覆盖和香根草篱措施下坡耕地红壤细菌群落结构特征及其影响因素     

成艳红  王馨悦  林小兵  黄尚书  张昆  何绍浪  王斌强  万长艳  黄欠如 《土壤》2021,53(3):522-528

为了揭示长期稻草覆盖和香根草篱措施下坡耕地红壤细菌群落结构特征,分析影响红壤细菌群落变化的主控环境因子,试验依托红壤坡地稻草覆盖和香根草篱等措施的水保效果长期定位试验,采用高通量测序技术,研究花生常规等高种植(CK)条件下,配合香根草篱(H)、稻草覆盖(M)和稻草覆盖+香根草篱(HM)措施对土壤细菌群落结构的影响,并分析细菌群落组成与土壤性状的相关性。结果表明:(1)与CK处理相比,H、M和HM处理土壤细菌丰富度和Shannon多样性指数均有增加,香根草篱和稻草覆盖措施均是增加土壤细菌丰富度的影响因素,稻草覆盖措施是增加土壤细菌多样性的主要影响因素,HM处理特有种细菌数量最多。(2)水保措施对土壤细菌群落结构产生影响,相比CK处理,M处理显著增加了变形菌门(Proteobacteria)细菌的相对丰度5.1%,降低了绿弯菌门(Chloroflexi)细菌的相对丰度,HM处理变形菌门和拟杆菌门(Bacteroidetes)细菌的相对丰度分别显著增加5.4%和1.2%,而H处理土壤细菌群落组成与CK处理间无显著差异。(3)主成分分析结果显示,有稻草覆盖处理(M和HM)的细菌群落结构相似,但与CK和H处理间细菌群落结构差异较大;典范对应分析表明,木聚糖酶、N-乙酰-β-D-氨基葡萄糖苷酶活性与细菌群落结构组成密切相关,土壤有机碳和硝态氮含量是影响细菌群落结构的主要环境因子。  相似文献   

论黄土高原区草畜产业循环经济     

毛玉胜 《中国牛业科学》2005,31(1):1-5

作者通过对黄土高原生态环境的巨变和存在问题,提出该区应实行草畜产业同步发展进行产业结构、技术、管理和制度创新,促进资源优化配置和技术重组。发展草畜产业可持续循环经济,应以草业为突破口,以牛羊业为经济增长点,从而提高环境效益,解决“三农问题”。  相似文献   

Lysine deficiency impaired growth performance and immune response and aggravated inflammatory response of the skin,spleen and head kidney in grown-up grass carp (Ctenopharyngodon idella)     

Yangyang Hu  Lin Feng  Weidan Jiang  Pei Wu  Yang Liu  Shengyao Kuang  Ling Tang  Xiaoqiu Zhou 《动物营养（英文）》2021,7(2):556

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草牧业高质量发展背景下的内蒙古草业科技进步贡献率测算     

钱政成  乌日汗  赵晓园  张苏日塔拉图  王强  李平  赵鸿鑫 《草地学报》2023,31(3):641-648

科技进步贡献率是测算一个产业经济发展中科技所占贡献值、衡量经济发展质量的重要指标。文章采用索洛余值法，并选取草业总产值，资本、劳动力和土地三大要素投入指标，对内蒙古“十五”至“十三五”时期草业科技进步贡献率进行测算，以此充分了解不同时期科技对草业经济发展的贡献作用。测算结果显示，内蒙古“十五”至“十三五”时期草业科技进步贡献率分别为29.33%,32.36%,38.22%,42.42%,同时预测“十四五”时期有望达到43.96%以上。整体上看，内蒙古草业科技进步贡献率呈现稳步增长的发展趋势，说明科技在草业经济发展中的贡献逐渐增大，但与同时期农业、畜牧业、林业等行业相比贡献率偏低，为实现科技引领草业经济高质量发展，需要加大科技资金的投入、加强人工草地建设、培育专业技术人员。  相似文献   

Impact of protection and free grazing on sand dune vegetation in the Rajasthan Desert,India     

M. Kumar  M. M. Bhandari 《Land Degradation \u0026amp; Development》1992,3(4):215-227

In the Thar (Rajasthan) Desert of India, sand dunes and sandy plains dominate the landscape. Livestock raising and marginal land cultivation are the main occupations. Owing to the high growth rates of human and livestock populations and a decrease in pasture area and its primary productivity, these lands bear acute grazing pressure. Average rainfall is low and vegetation growth is restricted to the short rainy season of two to four months duration. Often there are years of lower than normal rainfall. In these circumstances, fenced areas, established to stabilize formerly active sand dunes, are increasingly opened to grazing to prevent high stock mortality during droughts. This study was conducted in four fenced and one open site, representative of the region's different vegetation types and grazing pressures. The impact of 2 and 5 per cent free grazing pressure on protected sand dune vegetation density and cover was tested in the two fenced sites. The vegetation data for grazed sites are compared with those for the two ungrazed fenced (protected) and one unfenced (open) site subjected to unlimited grazing pressure throughout the year. The vegetation sampling was carried out by the qaudrat and line-transect method before and after grazing from November 1984 to October 1986. It shows a significant reduction in the density and cover of many palatable species and an increase of unpalatable plants. The effect of vegetation degradation is greater in the unfenced area. The low grazing pressure on the fenced sand dunes sites can still cause drastic changes in the vegetation density and cover. Protection resulted in reduced sand erosion and enhanced growth of palatable plants in the fenced sites under similar climatic and edaphic conditions to the unfenced sites. The grazing pressure in the unfenced areas remains high to extreme during the year, due to low land productivity and high feed demand. The regeneration rate is very slow under the constant (3rd to 5th degree) overgrazing. Low intensity grazing pressure on the fenced sites during droughts can cause heavy utilization and mortality of palatable vegetation.  相似文献