Data from: Plant, herbivore and parasitoid community composition in native Nothofagaceae forests vs. exotic pine plantations

1.Converting natural areas into land used for production causes dramatic changes in the configuration of landscapes. Both the loss and fragmentation of native habitats contribute to biodiversity loss worldwide and the consequent creation of artificial edges can have a significant influence on community assembly. The conservation value of plantation forests has been identified for specific species, but it is not clear whether exotic pine plantations can also be used for the preservation of native communities in general.

2.We studied whether community composition of different trophic levels (plants, herbivorous caterpillars, parasitoids) changed across native Nothofagaceae forests to exotic pine plantations, and whether habitat edges affected communities differently depending on the forest type considered. To accomplish this, we sampled plants, herbivorous caterpillars and parasitoids in native Nothofagaceae and exotic pine plantation forests and compared community composition of each trophic level across habitats.

3.We found that community composition of plants, herbivorous caterpillars and parasitoids differed significantly between native and exotic plantation forests, and that variation in the composition of the upper trophic levels was strongly dependent on variation in the composition of the lower trophic level. Moreover, differences in community composition were mostly the result of species turnover, suggesting that plantations are complementary habitats for some species, but cannot be a substitute habitat for all native forest species. Furthermore, edge effects had a strong impact on the composition of native communities, such that certain species were only present in the interior of the native habitat.

4.Synthesis and applications. Large areas of native vegetation, where the interior remains intact, are essential to preserve species that are susceptible to edge effects and that cannot occupy other habitat types. Creating straight instead of winding edges could decrease the impact that plantations have on native forests. Furthermore, increasing the representativeness of native plant communities in exotic plantation forests would cascade up to higher consumer trophic levels, considerably increasing the conservation value of these commercial stands.

1.将自然区域改造为生产用地会引发景观格局的剧烈改变。本地生境的丧失与破碎化均会在全球范围内导致生物多样性丧失，而人工生境边缘的形成亦会对群落构建产生显著影响。目前已有研究证实人工林对特定物种具有保护价值，但尚不清楚外来松人工林能否普遍用于保护本地群落。
2.本研究旨在探究不同营养级（植物、植食性毛虫、寄生蜂）的群落组成，在从原生南青冈科（Nothofagaceae）森林向外来松人工林的过渡梯度中是否发生改变，同时分析生境边缘对群落的影响是否因森林类型而异。为此，我们在原生南青冈科森林与外来松人工林中对植物、植食性毛虫及寄生蜂开展采样调查，并对比不同生境下各营养级的群落组成。
3.研究结果显示，原生林与外来松人工林之间，植物、植食性毛虫及寄生蜂的群落组成均存在显著差异；且较高营养级的组成变化，在很大程度上依赖于较低营养级的组成变化。此外，群落组成的差异主要源于物种更替，这表明人工林可为部分物种提供补充生境，但无法替代所有原生林物种的栖息环境。进一步而言，边缘效应对本地群落的组成具有显著影响，部分物种仅存在于原生生境的内部区域。
4.综合分析与应用启示。对于易受边缘效应影响且无法在其他生境中存活的物种而言，保留内部未受干扰的大面积原生植被区域是物种保护的核心前提。相较于蜿蜒曲折的林缘，营造平直的林缘结构可降低人工林对原生林的负面影响。此外，提升外来松人工林中本地植物群落的代表性，可将其生态效应向上级联至更高营养级的消费者，从而显著提升此类商品林的保护价值。