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建平县从2009年开始，至2013年末共完成辽西北草原沙化治理工程治理面积64万亩。为了准确反映草原沙化治理工程情况，对建设成果进行科学监测与客观评价，我们开展了辽西北草原沙化治理工程成效监测工作。1 基本情况 辽西北草原沙化治理工程是通过围栏、禁牧、牧草补播和天然草原改良等措施对现有沙化、退化草原进行治理。 相似文献
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本文介绍了博尔塔拉蒙古自治州天然草原退化情况,分析了博州草原退化的原因,提出了博州治理天然草原退化的对策和建议。 相似文献
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本研究旨在探讨联户放牧模式的概念、理论根源以及基于该模式对退化草原治理的实施效果，并针对当前草地管理模式存在的问题，提出未来草原管理政策的可行性建议。结果表明：面对草原退化，我国政府相继采取了草原管理政策，草原退化的趋势并没有被完全抑制。联户放牧模式的出现， 为遏制草原退化提供了一条创新途径，为实现草场高质量发展提供了实践视角。作为牧区地方治理的新模式，它虽然在一定程度上可以克服草原管理政策的缺陷，但仍缺乏国家政策的保护和政府的支持。 因此，在未来草地管理制度设计中应注重考虑 4 个方面：(1)牧区本土知识的应用；(2)新型职业牧民的培育；(3)基于自然解决方案的内容设计；(4)围栏拆建的科学性。 相似文献
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由于草原退化盐碱化，牧草稀少，改良草原工作逐年增加，国家各级政府部门都投入了大量的资金、人力和物力治理改良草原。改良草原需要选用不同的牧草品种，选用不当，会造成大量的资金浪费。 相似文献
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《饲料工业》2019,(18):54-58
应用电感耦合等离子-质谱技术(ICP-MS),建立饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅等元素的测定方法。对饲料样品的前处理方法、仪器工作参数和11种元素标准曲线进行优化;并以加标回收、分析方法比对和重复测试说明方法的准确性和精密性。方法在0～1 000 ng/ml范围内线性良好,仪器检出限为0.557 7～5.072 ng/ml,具有良好的精密度,其回收率在88.1%～104.4%之间,相对标准偏差小于5.0%。同时与原子吸收和原子荧光方法进行比对,测定结果相近。所建立的方法简单、快速,可替代原子吸收和原子荧光方法测定饲料中的11种金属元素,为饲料的质量控制提供理想的元素分析方法。 相似文献
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In experiment 1, 6 pregnant mares received a concentrate that contained a trace mineral premix that provided 14.3 mg Cu, 40 mg Zn, 28 mg Fe, 28 mg Mn, 0.08 mg Co, 0.16 mg I, and 0.16 mg Se/kg concentrate (group A). Seven mares received the same concentrate plus 502 mg Zn and 127 mg Cu once daily (group B). No differences (P > .05) in foal growth data, or Cu, Zn, and Fe concentrations of mare milk, mare serum, or foal serum were observed. In experiment 2, 6 pregnant mares received the same concentrate as group A (group C), and 8 mares received the same concentrate fortified with 4× the trace mineral premix (group D). Group C mares had higher serum Zn concentration at 1 day (P < 0.01) and 56 days (P < 0.04). Group C mares had higher milk Fe concentration at 28 days (P < .01), and group D mares had higher milk Cu concentration at 56 days (P < .01). Group C foals had higher serum Cu concentration at 14 days (P < .03). The results from this study provide no evidence to indicate that supplementing late gestating and lactating mares with higher dietary trace mineral levels than those recommended currently by NRC has any influence on foal growth and development, or on the Cu, Zn, and Fe concentrations of the mare milk, mare serum, or foal serum. 相似文献
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Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size. 相似文献
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液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量的不确定度评估 总被引：1，自引：1，他引：0
采用液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量,对标准溶液、体积、质谱峰面积、浓缩过程及回收率等测定不确定度因素进行了分析,通过评定各不确定度分量及标准不确定度,得出11种β-受体激动剂的扩展不确定度在0.7 ～ 1.1 ng/mL范围内.由各因素对合成不确定度的贡献比分析可知,影响较大的因素为试验回收率及标准溶液浓度. 相似文献