León-Gamboa Alba Lucía, Ramos Carolina, García Mary Ruth
Departamento de Biología, Universidad Nacional de Colombia, Bogotá, Colombia.
Rev Biol Trop. 2010 Sep;58(3):1031-48.
One of the most common problems in the Colombian mountains has been the replacement of native vegetation by pine plantations. Soil arthropods are a fundamental component of forest ecosystem, since they participate in the organic matter fragmentation, previous to decomposition. This role is more valuable in high altitude environments, where low temperatures limit the dynamics of biological processes, where the effects of pine plantations on soil arthropods are still not well-known. In a remnant of high-andean forest (Neusa - Colombia) and a pine plantation of about 50 years-old, it was evaluated the composition, richness and abundance of arthropods at surface (S), organic horizon (O) and mineral horizon (A) of soil, to establish the differences associated to the soil use transformation. It was used "Pitfall" sampling to register the movement of the epigeous fauna, and extraction by funnel Berlese for determining the fauna density from O and A horizons. The Shannon and Simpson indexes estimated the diversity at different places and horizons, and the trophic structure of the community was evaluated. Overall, there were collected 38 306 individuals from forest and 17 386 individuals from pine plantation, mainly distributed in Collembola (42.4%), Acari (27%), Diptera (17.6%) and Coleoptera (4.6%). The most important differences were given in the surface, where the mobilization in forest (86 individuals/day) almost triplicates the one in pine plantation (33 individuals/day). The differences in composition were given in Collembola, Araneae, Hemiptera, Homoptera and Hymenoptera. The dynamics of richness and abundance along the year had significant high values in the native forest than in the pine plantation. The general trophic structure was dominated by saprophagous (75%), followed by predators (14%) and phytophagous (9%), but in two layers of the pine plantation soil (S and O) this structural pattern was not given. Based on the results, it was concluded that pine plantations affect the diversity, composition, community dynamic and trophic structure of soil arthropods. Also, some estimators of soil stability give signals that these effects are reducing the ecosystem function in the region.
哥伦比亚山区最常见的问题之一是松树种植园取代了原生植被。土壤节肢动物是森林生态系统的基本组成部分，因为它们在有机物质分解之前参与其破碎过程。在高海拔环境中，这一作用更为重要，因为低温限制了生物过程的动态变化，而松树种植园对土壤节肢动物的影响仍不为人所知。在一片残余的高安第斯森林（内萨 - 哥伦比亚）和一个约50年树龄的松树种植园中，对土壤表层（S）、有机层（O）和矿质层（A）的节肢动物组成、丰富度和丰度进行了评估，以确定与土壤利用转变相关的差异。采用“陷阱”采样法记录地表动物的活动情况，并通过贝氏漏斗提取法确定O层和A层的动物密度。香农指数和辛普森指数估算了不同地点和层次的多样性，并对群落的营养结构进行了评估。总体而言，从森林中采集到38306个个体，从松树种植园中采集到17386个个体，主要分布在弹尾目（42.4%）、蜱螨目（27%）、双翅目（17.6%）和鞘翅目（4.6%）中。最重要的差异出现在表层，森林中的活动量（86个个体/天）几乎是松树种植园（33个个体/天）的三倍。弹尾目、蜘蛛目、半翅目、同翅目和膜翅目的组成存在差异。原生森林中节肢动物丰富度和丰度的年动态变化值显著高于松树种植园。总体营养结构以腐食性为主（75%），其次是捕食性（14%）和植食性（9%），但在松树种植园土壤的两层（S层和O层）中，这种结构模式并不存在。根据结果得出结论，松树种植园影响土壤节肢动物的多样性、组成、群落动态和营养结构。此外，一些土壤稳定性指标表明，这些影响正在降低该地区的生态系统功能。
