不同刈割频次下老芒麦和草地雀麦的生产力形成机制

摘要

本文于2013-2014年在内蒙古呼和浩特市和林格尔县种植的老芒麦(El ymus sibiricus)和草地雀麦(Bromus riparius)单播草地上进行不同频次刈割(一年刈割1次、2次、3次和4次)试验,调查各刈割处理产量、枝条数和植株高度,分析了老芒麦和草地雀麦产量的影响因子及其与枝条数和高度之间的关系.研究表明:刈割极显著降低了老芒麦的再生枝条数(P＜0.01),从而影响其产量,产量与植株高度无显著相关性;草地雀麦产量不受刈割频次的影响,刈割增加了其再生枝条数,在高频次刈割时会通过增加其再生枝条数来缓解植株高度降低的问题,但随着刈割茬次的增加其再生草产量仍会降低(P＜0.01).内蒙古呼和浩特地区老芒麦和草地雀麦的适宜的刈割频次均为每年2次.%We studied mowing times (one times,twice,third and forth times per year)on the monoculture grassland of Elymus sibiricus and Bromus riparius from 2013-2014 in Helinger Hohhot Inner Mongolia,and measured yield,number of sub-branches and heights of forages,then analysed the correlations between the impacting factors of yield and sub-braches and heights.Studies showed that mowing extremely reduced regeneration branch number of Elymus sibiricus (P＜0.01).,thus affected its production.The correlations between yield and heights of Elymus sibiricus were not significant.Mowing frequency had no effect on the yield of Bromus riparius,but mowing increased its regeneration branch number.High frequency mowing increased the regeneration branch numbers to alleviate the problem of low plant height.But regeneration grass production extremely reduced with the increase of mowing frequency(P＜0.01).The best mowing times of Elymus sibiricus and Bromus riparius were twcie per year in Hohhot Inner Mongolia.