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文摘
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两年的牦牛放牧试验结果表明:随放牧率的增加, 夏季草场各土壤层有机质、有机碳、全氮和全磷的含量呈下降趋势,它们的含量与放牧率呈显著的线性回归关系, 速效氮的含量与放牧率呈二次回归关系, 各土壤营养因子平均含量与放牧率也有类似的关系.而且当放牧率分别达到1.07 heads/hm2、1.08 heads/hm2和1.22 heads/hm2时, 0～5 cm、 5～10 cm、 10～20 cm土壤速效氮含量依此达到最小,若放牧率继续增加,各土壤层速效氮的含量依此开始增加, 而速效氮的平均含量达到最小的放牧率是1.08 heads/hm2.在相同放牧率下, 有机质和有机碳的含量在各土壤层之间差异极显著(P<0.01),全磷差异显著(P<0.05),全氮和速效氮差异不显著(P>0.05),而且放牧率和土壤深度的交互作用对土壤各营养因子含量的影响极显著(P<0.01).放牧率对各土壤层的含水量有显著的影响(P<0.05),不同年度间同一土壤层含水量的差异不显著(P>0.05). |
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其他语种文摘
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Effects of stocking rates on contents of soil nutrient and water in summer pasture of alpine mead-ow had been studied for two years. The result showed that contents of organic matter, organic C, total N and total P decreased in the same stratum with the increase of stocking rates, and there was a significant linear regression relationship between their contents and stocking rates, the second degree polynomial re-gression between stocking rates and contents of available N. and then average nutrient contents of every nutrient factors (0-20 cm soil layer) had a similar response with contents of every stratum. And the contents of 0~5 cm, 5-10 cm, 10~20 cm soil layer for available N reached to the minimum values succes-sively when stocking rates equaled to 1. 64, 1. 73 and 1. 97 heads/hm2 respectively, and stocking rate was 1. 67 heads/hm2 average contents of available N reaching to the peak value, and then contents of available N began increasing continually. Contents 'of organic matter, organic C were extremely significant differ-ence in different stratums under the same stocking rates (P<0. 01), significant difference for total P(F< 0. 05) and no significant difference for total N and available N (P>0. 05), and the interactions of stocking rates and grazing time had an extremely significant effect on contents of every nutrient factor in different soil stratum (P<C0. 01). Besides, effect of stocking rates on water contents of every stratum was signifi-cant (P<0. 05) , the yearly change was not significant (P>0. 05). |
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来源
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西北植物学报
,2004,24(12):2228-2236 【核心库】
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关键词
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牦牛放牧率
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小嵩草高寒草甸
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夏季草场
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土壤营养因子
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养分含量
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土壤水分含量
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地址
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1.
中国科学院西北高原生物研究所, 西宁, 810002
2.
青海省畜牧兽医科学院, 西宁, 810003
3.
青海省果洛州草原站, 青海, 大武, 814000
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语种
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中文 |
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文献类型
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研究性论文 |
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ISSN
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1000-4025 |
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学科
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植物学 |
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基金
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青海省“九五”科技攻关项目
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国家“十五”科技攻关项目
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文献收藏号
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CSCD:1809754
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