摘要
在羊草＋苔草低地草甸,通过小区围栏放牧,定量研究了不同放牧率对低地草甸牧草再生性能和地上净初级生产力的影响。结果表明：在不同放牧率下各再生期间的再生草量存在着明显的季节性差异,其最大值出现在5-6月份,为136.6 g/m^2。适宜的放牧率有利于增加草地的再生草量,各放牧小区的相对生长速率均大于对照小区的相对生长速率,放牧率较低的P2小区相对生长速率最大。各放牧小区地上净初级生产力均小于对照小区地上净初级生产力,即不存在超补偿性生长现象。
In this paper, the influence of different cow grazing rates on herbage regeneration and aboveground net primary productivity is quantitatively lucubrated by carrying out the experiment of grazing cows in 5 fenced plots in a lowland meadow dominated by Leymus chinensis and Carex sp. , and the areas of the fenced plots are 10 m ×24 m, 10 m ×21 m, 10 m × 18 m, 10 m ×15 m and 10 m × 10 m respectively. The study area （42°40＇ -43°42＇N, 121°30＇- 123°43＇E） is located in Kozohou Banner, Tongliao City, Inner Mongolia, and it is a transitional zone with climatic pattern shifting from semi-humid one to semiarid one. Where the annual temperature, frost-free period and annual precipitation vary in ranges of range of 5.3 - 5.9 ℃, 138 - 148 days and 358 - 483 mm respectively, the annual precipitation is 3.9- 4.5 times of annual precipitation, the dominant plant species are Carex sp. , Leymus chinensis, Hierochloe glabra, Phragmites communis, Potentilla anserine, Taraxacum mongolicum, etc. , and the proportion of dried herbage of Carex sp. , Leymus chinensis, Phragmites communis and Hierochloe glabra is over 95% of the total dried herbage. The results reveal that there is a high seasonal difference in regenerating biomass under different grazing rates, and the maximum regenerating biomass, 136.6 g/m^2, occurs during the period from May to June. An adaptive grazing rate benefits to increase the regenerating biomass. The relative regenerating rates in all the experimental grazing plots are higher than that in the contrast plots, and the relative regenerating rate of experimental grazing plot P2 with low grazing rate is the highest. The aboveground net primary productivities in all the experimental grazing plots are lower than that in the contrast plots, that is there is no an overcompensatory growth under various grazing rates.
出处
《干旱区研究》
CSCD
北大核心
2007年第6期826-829,共4页
Arid Zone Research
基金
国家重点基础研究规划发展项目(2000018602)
关键词
放牧率
草甸
牧草再生
净初级生产力
羊草+苔草
通辽
内蒙古
grazing rate
meadow
herbage regeneration
aboveground net primary productivity
Inner Mongolia.
