Smith DiCarlo Lauren A, DeBano Sandra J
Department of Environmental Science, Westfield State University, Westfield, MA 01086, USA.
Department of Fisheries and Wildlife, Oregon State University, Hermiston, OR 97838, USA.
Insects. 2021 Mar 16;12(3):249. doi: 10.3390/insects12030249.
Grassland restoration in North America has intensified but its impact on major invertebrate groups, including spiders, is unclear. We studied three grassland locations in the Pacific Northwest, USA, to (1) describe variability in spider communities, (2) identify environmental variables that may underlie patterns in spider communities, and (3) determine whether spiders and environmental variables differ between actively (removal of disturbances, then plant with natives) vs. passively restored sites (removal of disturbance only). We found spider richness, diversity, and composition differed among the three locations but abundance did not. Sites with more litter and invasive grass cover had more spiders while sites at higher elevation and with more forb and biological soil crust cover had increased spider richness and diversity. Spider community composition was associated with elevation and litter cover. Surprisingly, no spider community or environmental variables differed between actively and passively restored sites, except that litter cover was higher in passively restored sites. This study demonstrates that even in superficially similar locations, invertebrate communities may differ greatly and these differences may prevent consistent responses to active vs. passive restoration. If increasing biodiversity or the abundance of invertebrate prey are goals, then environmental factors influencing spider communities should be taken into account in restoration planning.
北美草原恢复工作已得到加强，但其对包括蜘蛛在内的主要无脊椎动物类群的影响尚不清楚。我们研究了美国太平洋西北部的三个草原地点，以（1）描述蜘蛛群落的变异性，（2）确定可能是蜘蛛群落模式基础的环境变量，以及（3）确定在主动恢复（去除干扰，然后种植本地植物）与被动恢复地点（仅去除干扰）之间蜘蛛和环境变量是否存在差异。我们发现，三个地点的蜘蛛丰富度、多样性和组成存在差异，但丰度没有差异。凋落物和入侵草覆盖较多的地点蜘蛛较多，而海拔较高、 forb和生物土壤结皮覆盖较多的地点蜘蛛丰富度和多样性增加。蜘蛛群落组成与海拔和凋落物覆盖有关。令人惊讶的是，主动恢复和被动恢复地点之间的蜘蛛群落或环境变量没有差异，只是被动恢复地点的凋落物覆盖更高。这项研究表明，即使在表面相似的地点，无脊椎动物群落也可能有很大差异，这些差异可能会阻碍对主动恢复与被动恢复的一致反应。如果增加生物多样性或无脊椎动物猎物的丰度是目标，那么在恢复规划中应考虑影响蜘蛛群落的环境因素。
