吉林蛟河阔叶红松林地表甲虫多样性时间动态分析

An analysis of temporal dynamics of litter-layer beetles in broad-leaved Korean pine forest in Jiaohe,Jilin Province

阔叶红松林是长白山林区代表性植被类型,具有较高的生物多样性。研究吉林蛟河阔叶红松林中地表甲虫多样性的时间动态,比较优势类群对时间变化的响应,为森林中地表甲虫的保护与利用提供科学依据。在2012—2013年5月中旬至8月下旬整个地表甲虫的活跃期,利用巴氏罐法在吉林蛟河阔叶红松林4个样地中共采集地表甲虫9849头,隶属于22个科79种,步甲科Carabidae、埋葬甲科Silphidae和隐翅虫科Staphylinidae为优势类群。地表甲虫的物种数、个体数和多样性指数均在7月上旬时达到最高,时间对个体数有显著影响(P<0.05)。地表甲虫多样性各指数间相关性较低,个别种类对环境变化比较敏感。步甲科个体数在7月上旬显著高于其他时间,物种数与个体数的时间动态不一致,步甲科对8月上旬的适应能力强于埋葬甲科和隐翅虫科。埋葬甲科在7月上旬个体数量极显著高于其他各时间(P<0.01),物种数与个体数的时间动态相一致。埋葬甲科对7月下旬适应能力强于隐翅虫科,其对时间变化的反应最敏感,当环境条件适宜时,其数量能够迅速增加。不同时间隐翅虫科的物种数与个体数变化相对较小,对时间变化的敏感程度最低。由于生活习性的特殊化,使得捕食性和腐食性地表甲虫活跃的高峰期也可能与被捕食者在各时期的数量有关。

Broad-leaved Korean pine forest is a typical zonal forest community in the eastern forest area of China, with high biodiversity. The temporal dynamics of the diversity of litter-layer beetles was investigated in broad-leaved Korean pine forest in Jiaohe, Jilin Province, and the responses of dominant groups were compared in different times, in order to provide scientific basis for the protection and utilization of litter-layer beetles in forests. Litter-layer beetles were collected by pitfall traps in adult beetles entire active period from mid May to late August during 2012 to 2013 at 4 sampling plots in the broad-leaved Korean pine forest. In total, 9849 specimens were collected, belonging to 22 families and 79 species, among which Carabidae, Silphidae, and Staphylinidae were the dominant groups. The species number, individual number and diversity index of litter-layer beetles were the highest in early July, and time had a significant impact on the number of individuals （P 〈 0.05）. There was a low correlation among each index of litter-layer beetles, some species were more sensitive to environmental changes. The individual number of Carabidae in early July was significantly higher than during other times, and temporal dynamics of species number and individual number were not accordant. Additionally, the adaptability of Carabidae was higher than that of Silphidae and Staphylinidae in August. The individual number of Silphidae in early July was significantly higher than at other times （P 〈 0.01）, and the temporal dynamics of species number and individual number were consistent. The adaptability of Silphidae was higher than that of Staphylinidae in July. The response of Silphidae to time change was the most sensitive, and their individual number could increase rapidly when the environmental conditions were appropriate. The variation of species and individual number of Staphylinidae was relatively small at different times, and the sensitivity of Staphylinidae to time change was the lowest. Because of the special life habits, the activity peak of predatism and saprophagous litter-layer beetles may be linked to the number of prey insects during every period.