摘要
刈割是典型草原的主要利用方式之一,探究长期刈割背景下草原优势物种密度和生物量的年际变化,可为典型草原明确优良牧草开发利用提供理论依据.本研究基于典型草原的长期刈割试验(1982～2022年),设置连年刈割(留茬6 cm)和对照(不刈割)两种处理,探究典型草原优势物种羽茅密度和生物量对长期刈割的年际响应动态.结果表明:与对照相比,长期连年刈割降低了羽茅的密度和生物量且年际间波动较大,其生物量在第20年(2001年)时开始显著降低(P＜0.05),而到第30年(2011年)则达到极显著降低(P＜0.01).总体看来,羽茅前期为耐刈割物种,由于长期刈割产生的累加效应,使其生物量产生波动下降趋势,而后期羽茅转变为不耐刈割物种.羽茅生长对长期刈割的规律可为典型草原可持续利用提供重要参考.
Abstract
Mowing is one of the primary management in typical steppe,and the study of interannual changes in density and biomass of dominant species under long-term mowing can provide a theoretical basis for clarifying the development and utilization of superior forage in typical steppe.A long-term(1982～2022)mowing experiment in a typical steppe was conducted with successive mowing(leaving a stubble height of 6 cm)and control(no mowing)to investigate interannual variations of plant density and biomass of the dominant species Achnatherum sibiricum.The results showed that long-term successive mowing sig-nificantly decreased the density and biomass of A.sibiricum with wider interannual fluctuations.A.sibiri-cum biomass began to decrease in the 20th year(P＜0.05)and the decrease was highly significant in the 30th year(P＜0.01).Overall,A.sibiricum initially exhibited greater resistance at the start of mowing.Plant density and biomass,however,showed a fluctuating declining trend,and gradually turned to low mowing tolerant species due to the cumulative effects of mowing.The growth response of A.sibiricum to mowing provides crucial evidence for the sustainable utilization of typical steppes.
基金项目
"科技兴蒙"重点专项(2020-科技兴蒙-草种业技术创新中心-2)
&&(2021GG0415)
维普
万方数据