蓟马在苜蓿上的空间分布格局研究

Spatial distribution pattern of thrips on alfalfa

为了明确蓟马在苜蓿(Medicago sativa)上的空间格局,应用聚集度指标和Iwao的回归法分别检验了蓟马在苜蓿上的分布型。结果表明,蓟马在苜蓿上是以个体群为基本分布成分,个体群间的分布属聚集分布,其聚集强度随苜蓿刈割次数的增加而下降,而蓟马的聚集是由于某些环境因素以及本身习性引起的。此外,本研究还应用Iwao模型中的参数建立了最适抽样数的计算公式。

In order to explore the spatial distribution pattern of thrips on alfalfa （Medicago sativa）, aggregation indexes and Iwao regression methods were used in this study. The results showed that the distribu- tion of thrips on alfalfa behaved as the clustered colonies and the aggregation intensity decreased with the increasing of cutting times. The aggregation was affected by environmental factors and thrips habits. Based on the parameters fitted by the Iwao model, the equation of optimal sampling number was proposed.