Department of Botany and Zoology, Masaryk University, Brno, Czech Republic.
J Insect Sci. 2012;12:61. doi: 10.1673/031.012.6101.
This study shows that disturbance caused by cover-crop removal (CCR) in an organic olive orchard affects ground-spider populations. The effect of CCR on various organic olive-orchard plots was assessed by monitoring the abundance and diversity of ground-dwelling spiders. Covered plots in the organic olive orchard were compared with uncovered plots where the covers had been removed mechanically. CCR positively affected the most abundant spider species Zodarion styliferum (Simon) (Araneae: Zodariidae) as well as other species of running spiders belonging to the families Gnaphosidae and Lycosidae. Over time, the two types of plots did not significantly differ in diversity or dominance. Similarly, no differences were detected between the study plots in terms of the distribution of individuals when a cluster-similarity analysis was performed. This lack of difference in diversity might be due to the spatial scale used in the study or climatology. Because of their general effects, CCR profoundly changed the abundance of spiders in the olive orchard, but with no clear impact on spider diversity.
本研究表明,有机橄榄园中覆盖作物移除(CCR)所造成的干扰会影响地蛛种群。通过监测地面蜘蛛的丰富度和多样性,评估了 CCR 对不同有机橄榄园地块的影响。与机械去除覆盖物的未覆盖地块相比,有机橄榄园中覆盖地块的蜘蛛数量明显增加。CCR 还会对最丰富的蜘蛛物种(西蒙氏扎多里翁Styliferum)(蜘蛛目:扎多里翁科)和其他属于狼蛛科和狼蛛科的奔跑蜘蛛产生积极影响。随着时间的推移,两种类型的地块在多样性或优势度方面没有显著差异。同样,在进行聚类相似性分析时,研究地块之间个体的分布也没有差异。这种多样性差异不明显可能是由于研究中使用的空间尺度或气候条件所致。由于 CCR 的普遍影响,它极大地改变了橄榄园中蜘蛛的丰富度,但对蜘蛛多样性没有明显影响。