不同时期刈割对互花米草生长影响的研究

The Effect of Mowing on Growth of Spartina alterniflora

采用不同时期对互花米草(Spartina alterniflora)进行齐地面刈割的方法,通过对互花米草株高和株数的测定和比较,确定了有效控制互花米草扩张的刈割时期。研究结果表明:①4月22日对互花米草的刈割处理显著促进了互花米草株数的增加,但对其最终平均株高未产生影响。5月22日的刈割处理下,虽然互花米草在株高上略高于对照(未刈割)处理,但处理后其株数大大减少,与对照处理相比有明显差异。6月21日和7月21日的刈割处理,不仅使互花米草株高降低,也使其株数减少;尤其是7月21日的刈割处理下,互花米草的株数和株高都与对照处理有非常明显的差异。8月20日和9月19日的刈割处理,极大促进了互花米草的再萌发和再生长。②5～7月的刈割处理,可以有效减少互花米草的活根生物量;而4月和8～9月的各刈割处理,增加了互花米草的活根生物量,其中4月22日的刈割处理与对照处理相比,显著促进了互花米草活根生物量的增加。各刈割处理都会造成互花米草死根生物量的增加。③有效控制互花米草种群扩张的刈割时期是6～7月互花米草的穗分化期、孕穗期至抽穗期。

Using the method of mowing to harvest the Spartina alterniflora and by testing height and seedling number of the plants,the most suitable mowing period of controlling S.alterniflora was studied.The results showed that mowing S.alterniflora on April 22 greatly increased the number of seedlings,but there was no obvious effect on the height increase.The average height of mowing on May 22 was just higher a little than that of the control group,but the seedling number was greatly higher than that of the control group.Both of height and seedling was obviously reduced by mowing on June 21 and July 21,especially on July 21.However,moving on August 20 and September 19 enhanced the growth of height and seedling number of the plants.The living root biomass was reduced when S.alterniflora was mown during May to July,but it was increased mown on April 22,August 20 and September 19,especially on April 22;the dead root biomass was increased whenever it was mown.The best control period on S.alterniflora growth was from June to July.