Goosey H B, McKenzie S C, Rolston M G, O'Neill K M, Menalled F D
Department of Animal and Range Sciences, 103 Animal Bioscience Building, P.O. Box 172900, Montana State University, Bozeman, MT 59717-3120.
Department of Land Resources and Environmental Sciences, 334 Leon Johnson Hall, P.O. Box 3120, Montana State University, Bozeman, MT 59717-3120.
Environ Entomol. 2015 Aug;44(4):1052-64. doi: 10.1093/ee/nvv104. Epub 2015 Jul 9.
Growing concerns about the environmental consequences of chemically based pest control strategies have precipitated a call for the development of integrated, ecologically based pest management programs. Carabid or ground beetles (Coleoptera:Carabidae) are an important group of natural enemies of common agricultural pests such as aphids, slugs, and other beetles. Alfalfa (Medicago sativa L.) is one of the most common forage crop species in the semi-arid western United States. In 2011, Montana alone produced 4.0 × 10(6 )Mg of alfalfa on 8.1 × 10(5 )ha for gross revenue in excess of US$4.3 × 10(8), making it the third largest crop by revenue. We conducted our study over the 2012 and 2013 growing seasons. Each year, our study consisted of three sites each with adjacent systems of monoculture alfalfa, alfalfa nurse cropped with hay barley, and an uncultivated refuge consisting of a variety of forbs and grasses. Carabid community structure differed and strong temporal shifts were detected during both 2012 and 2013. Multivariate fuzzy set ordination suggests that variation in canopy height among the three vegetation systems was primarily responsible for the differences observed in carabid community structure. Land managers may be able to enhance carabid species richness and total abundance by creating a heterogeneous vegetation structure, and nurse cropping in particular may be effective strategy to achieve this goal.
对基于化学方法的害虫防治策略所产生的环境后果的日益担忧，促使人们呼吁制定综合的、基于生态的害虫管理计划。步甲科昆虫或地甲虫（鞘翅目：步甲科）是常见农业害虫（如蚜虫、蛞蝓和其他甲虫）的重要天敌群体。苜蓿（紫花苜蓿）是美国西部半干旱地区最常见的饲料作物品种之一。2011年，仅蒙大拿州就在81万公顷的土地上生产了4.0×10⁶公吨的苜蓿，总收入超过4.3×10⁸美元，使其成为按收入计算的第三大作物。我们在2012年和2013年的生长季节进行了研究。每年，我们的研究包括三个地点，每个地点都有相邻的单作苜蓿系统、与大麦干草间作的苜蓿以及由各种草本植物和禾本科植物组成的未开垦避难区。2012年和2013年期间，步甲群落结构不同，且检测到强烈的时间变化。多变量模糊集排序表明，三种植被系统之间冠层高度的差异是导致步甲群落结构差异的主要原因。土地管理者或许能够通过创造异质植被结构来提高步甲物种丰富度和总丰度，特别是间作可能是实现这一目标的有效策略。
