摘要
以自由放牧为对照，采用收获法和土芯法研究了围栏禁牧对蒙占国退化克氏针茅草原地上、地下部生长的影响，结果表明：（1）与自由放牧相比，围栏禁牧提高了退化草原地上生物量，以及地带性草原群落优势种克氏针茅的地上生物量比例和重要值，促进了退化克氏针茅的正向恢复演替；（2）围栏禁牧区与自由放牧区草地地下生物量都随土层深度增加而降低、符合指数函数或幂函数减小规律，围栏禁牧区0～10cm土层的根系生物量占地下生物量比例高于自由放牧区，10～20cm土层的低于自由放牧区，根系有向E层土壤聚集的趋势，有利于在干旱地区对有限降水的有效利用；（3）围栏1～3a禁牧区地下部累计生产力显著高于同期自由放牧区。围栏禁牧是蒙古国退化克氏针茅草原改良的一种措施，但其提高地下生产力和生物量的效应也不是无限制的。
With grazing allowed as the control,the effects of grazing blocked by fencing on aboveground and under ground growth in Stipa krylovii steppe of Mongolia were investigated by soil coring and harvesting method. It was indicated that （1） compared with grazing allowed, grazing blocked by fencing raised aboveground biomass of the steppe and aboveground biomass proportion and importance values of S. krylovii dominating in zonal grassland communities, and boosted the forward-direct recovery succession of de- generated S. krylovii; （2） The underground biomass declined in both the areas covered by grazing blocked by fencing and the area suffering grazing allowed as their soil layers become deeper in the areas,following the declining pattern depicted by the exponential function or the power function;the root biomass proportion to the underground biomass in the area covered by grazing blocked by fencing was higher than that in the areas suffering free grazing in 0-10 cm soil but higher than that in the areas suffering grazing allowed in 10-20 cm soil, and this indicated that the roots tended to concentrate towards upper soil, which was helpful to effective limited rainfall use in arid areas; （3） The underground accumulative productivity in the area where grazing were blocked by fencing for 1-3 year.s was significantly higher than that in the area suffering grazing allowed. Grazing blocked by fencing is a practice for Mongolia to improve its degenerated S. krylovii steppe,but its effects of raising the underground productivity and biomass are not limitless.
出处
《西北植物学报》
CAS
CSCD
北大核心
2006年第12期2540-2546,共7页
Acta Botanica Boreali-Occidentalia Sinica
基金
日本科学技术振兴事业团战略基础研究推进事业项目
关键词
围栏禁牧
生物量
克氏针茅草原
蒙古国
Grazing blocked by fencing
biomass
Stipa krylovii steppe
Mongolia
