新疆伊犁天然草地白喉乌头种群分布格局

Population distribution pattern of Aconitum leucostomumin Ili grassland,Xinjiang

针对伊犁河谷天然草地毒害草综合治理问题,选取当地毒草优势种白喉乌头(Aconitum leucostomum)种群为研究对象,在其进入生殖生长前依据株丛基生叶片数量将白喉乌头株丛划分为3个级别,即Ⅰ级、Ⅱ级和Ⅲ级株丛。利用4种聚集度指标及Moristia指数(Iδ)分布格局判定方法,研究了自由放牧样地和围栏封育+打草样地中白喉乌头种群的结构特征及不同级别的分布格局。结果表明:1)在自由放牧区和围栏封育+打草区内,白喉乌头种群总体及Ⅰ级株丛均为集群分布,Ⅱ级株丛均为随机分布,Ⅲ级株丛在自由放牧区为均匀分布,而在围栏封育+打草样地内则为随机分布;2)连续4年生长季节的围栏封育有利于白喉乌头种子的萌发,且对白喉乌头种群控制效果不明显。

Natural grassland weeds poisonous problem of Ili River valley is serious. Aconitum leucostomum were scaled intoⅠ, Ⅱ and Ⅲ bunch grade according to the number of strains bunch basal leaves before its reproductive growth because this specie was the dominant. Four different aggregate indices and Moristia index Iδ distribution pattern determination method were employed to study A.leucostomum population structure and distribution pattern in different plots under free grazing or fencing with mowing. In free grazing plot and fencing with mowing plot, grade Ⅰ A.leucostomum were clumped, gradeⅡ A.leucostomum randomly distributed. grade Ⅲ A.leucostomum evenly distributed in free grazing plot and randomly distributed in fencing with mowing plot. After four consecutive years fencing in growing season, it was beneficial to A.leucostomum seed germination and was profitless for population control.