刈割处理对贝加尔针茅草原植物生长与繁殖状况的影响 I、当年处理的效果及对返青状况的影响

在内蒙古锡林郭勒高原东部的贝加尔针茅草原上，选择丘间宽阔平地设置研究样地，在围栏封闭条件下，以群落为研究对象，采用固定双样方随机区组的方法，于1998年5月－1999年9月，对植物进行了不同强度和不同时间的刈割研究，观察植物营养生长和生殖生长因不同处理而发生的变化，从而判断对整个群落植物生长与繁殖的影响。结果表明，从群落主要种到整个草群，其处理当年及返青后的高度、盖度、植株数量等指标基本上随刈割强度加大和刈割时间推后而降低，繁殖活动状态也是依相同的顺序而变差，1年1次处理的效果即很明显且有残效。为合理安排草地的利用计划提供了参考依据。

EFFECTS OF CUTTING TREATMENTS ON PLANT GROWTH AND REPRODUCTIVE STATUS IN Stipabaicalensis STEPPE

In Stipa baicalensis steppe of the eastern zone of Xilingaole Plateau,Inner Mongolia,broad plain were chosen to set up research site.On the base of whole steppe community,eight blocks of paired quadrates(treatment and check) were arranged in randomized blocks.Plants in the quadrates were cut with different stubble heights at designed times from May,1998 to September,1999 and the community features in the cutting year and next spring were observed to investigate the changes of plant vegetative growthe and reproductive growth to assess the effects of cutting intensities and cutting times on community plant growth and reproduction.The results showed that from dominated species to whole community,the height,coverage,number of plants to a great extent declined with the increase of cutting intensity and with delayed cuttings.Also the reproductive status became worse according to the same order.The effects were quite significant when treated just once a year.This provided a theoretical base for arranging proper steppe utilization programme.