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作 者:裴海昆[1]
出 处:《青海大学学报(自然科学版)》2004年第4期29-31,共3页Journal of Qinghai University(Natural Science)
基 金:国家自然科学基金(39960053)
摘 要:在高寒草甸植被下,通过在放牧强度依次为每公顷8只、4只、2只、0只藏羊的条件下对土壤养分状况影响的试验表明,随着放牧强度的增加,土壤有机质含量逐渐减少,由对照的11.217%降低到重度放牧的8.632%;而速效氮含量增加,速效钾的含量减少,但均低于对照;速效磷含量及pH基本保持不变,土壤质地也无明显变化。随着放牧强度的增加,交换性Ca、Mg含量逐渐降低,而交换性Na略有上升。The effect of the different grazing intensity (8,4,2,0 sheep/hm^2) on the condition of soil nutrient were studied in the vegetation of the alpine-cold meadow.The results showed that the content of the soil organic matter was declined with increasing the grazing intensity,which decreased from 11.217% of the control group to 8.632% of the heaviest grazing group.The content of rapid available nitrogen increased and the content of rapid available potassium decreased with increasing the grazing intensity,but the content of all was lower than that of the control group.The content of rapid available phosphorus,pH and soil texture was distinctly unchanged.By increasing grazing intensity,the content of exchangeable Ca and Mg decreased and the content of exchangeable Na increased a little.
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