白龙江林区地表甲虫沿海拔梯度的群落结构及动态分析

Community structure and dynamics of ground beetles along an altitudinal gradient in the Bailongjiang forest

【目的】揭示白龙江林区地表甲虫群落沿海拔梯度(927-2735 m)的多样性格局、群落结构及动态变化,为林区内生物多样性长期监测及保护提供理论基础和依据。【方法】采用巴氏罐诱捕法,沿不同海拔梯度(927、1794、2376和2735 m)设置陷阱诱集地表甲虫。【结果】共采集2015头地表甲虫,包括18科95种。虎甲科Cicindelidae的个体数量最多(436只)占总数的21.6%,其次是叩甲科Elateridae、步甲科Carabidae、葬甲科Silphidae、隐翅甲科Staphylinidae。5个科的采集数量占到总数的75.1%,是白龙江地区优势种群。随着海拔梯度的升高,流域内地表甲虫的数量及优势种群数量都呈先上升后下降的趋势。在海拔2376 m处,地表甲虫丰富度最高,诱集数量最多。低海拔地区地表甲虫丰富度低,诱集数量少。在种群动态变化中,中高海拔地区的优势种群在6-9月间的种群数量变化趋势呈单峰增长模式,且不同海拔高度不同科种群的诱集峰值不同。如在不同海拔梯度内诱集的步甲科数量均在7月份最多;在海拔2376 m处,叩甲科个体数量在8月份最多,相比海拔较低的1794 m处,则7月份数量最多,在低海拔927 m处和高海拔地区2735 m处,叩甲科的个体数量急剧减少,且动态变化不明显。【结论】在白龙江林区拱坝河流域,地表甲虫种类丰富,优势种群明显。在不同海拔梯度上,其优势种群表现出不同的变化模式。根据地表甲虫群落在海拔梯度上的分布,可将地表甲虫分为三类。一是分布在中高海拔,包括步甲科、隐翅甲科及虎甲科等,在流域内4个不同海拔梯度都有分布。二是在中高海拔和高海拔处种类丰富,在低海拔处未诱集到相应甲虫,包括叩甲科及葬甲科。三是在不同海拔高度都有分布,但数量少,未形成优势种群,包括金龟科、象甲科及瓢虫科等。

[Objectives]To describe the diversity,community structure and change in the ground beetle community along an altitude gradient(927-2735 m)in the Bailong River forest area,and demonstrate the benefits of long-term monitoring and protection of forest biodiversity.[Methods]Babbitt pot traps were set at different altitudes(927,1794,2376,2735 m)to capture ground beetles.[Results]A total of 2015 ground beetles were caught,which could be classified into 95 species and 18 families.Among these,the Elateridae,Carabidae,Silphidae,Staphylinidae and Cicindelidae were the dominant families comprising 75.1%of all species captured.The most numerically abundant family was the Cicindelidae which comprised 436 individuals or 21.6%of the total.The number of dominant species first increased,then decreased,along the elevation gradient.Both the diversity and number of beetles trapped were highest at 2376 m,whereas both diversity and abundance were relatively low in low altitude areas.The number of dominant species in middle and high altitude areas had a single-peak growth pattern from June to September.Peak capture values differed among families at different altitudes.For example,the Carabidae were the most abundant beetles caught in July at all altitudes.However,the Elateridae were the most frequently caught in August at 2376 m and 1794 m.Conversely,the number of Elateridae captured decreased sharply at 927 m and 2735 m.[Conclusion]Ground beetle species are abundant and dominant species are obvious in the Gongba River basin of the Bailongjiang forest.Dominant species varied with altitude.Ground beetles can be categorised into three types according to their distribution on the altitude gradient.The Mid-high altitude group includes the Carabidae,Staphylinidae and Cicindelidae,which are widely distributed at 4 different altitudes in the basin.The mid-high and high-altitude group,includes the Elateridae and Silphidae.The third group,comprised of the Scarabaeidae,Curculidae and Coccinellidae,are found at all altitudes,but are less abundant and are not dominant taxa at any altitude.