Costa Cristiane, Oliveira Victor Hugo F, Maciel Rafaella, Beiroz Wallace, Korasaki Vanesca, Louzada Julio
Setor de Ecologia/Departamento de Biologia, Universidade Federal de Lavras, Lavras, MG, Brazil.
Lancaster Environment Centre, Lancaster University, Lancaster, United Kingdom.
PeerJ. 2017 Apr 4;5:e3125. doi: 10.7717/peerj.3125. eCollection 2017.
Conserving biodiversity in tropical landscapes is a major challenge to scientists and conservationists. Current rates of deforestation, fragmentation, and land use intensification are producing variegated landscapes with undetermined values for the conservation of biological communities and ecosystem functioning. Here, we investigate the importance of tropical variegated landscapes to biodiversity conservation, using dung beetle as focal taxa.
The study was carried out in 12 variegated landscapes where dung beetles were sampled using six pitfall traps, 30 m apart from each other, along a transect in each studied landscape use and cover classes-LUCC (forest fragment and corridor, coffee plantation, and pasture). We baited each pitfall trap with 30 g of human feces and left open for a 48 h period. We also measured three environmental variables reflecting structural differences among the studied classes: canopy cover, local vegetation heterogeneity and soil sand content.
We collected 52 species and 2,695 individuals of dung beetles. We observed significant differences in the mean species richness, abundance and biomass among classes, with forest fragments presenting the highest values, forest corridors and coffee plantations presenting intermediate values, and pastures the lowest values. Regarding community structure, we also found significant differences among classes. Canopy cover was the only variable explaining variation in dung beetle species richness, abundance, biomass, and community structure. The relative importance of spatial turnover was greater than nestedness-resultant component in all studied landscapes.
This study evaluated the ecological patterns of dung beetle communities in variegated tropical landscapes highlighting the importance of these landscapes for conservation of tropical biodiversity. However, we encourage variegation for the management of landscapes that have already been fragmented or as a complementary initiative of current conservation practices (e.g., protection of natural habitats and establishment of reserves).
在热带地区保护生物多样性是科学家和保护主义者面临的一项重大挑战。当前森林砍伐、碎片化以及土地利用集约化的速度正在形成多样化的景观，这些景观对于生物群落保护和生态系统功能的价值尚未确定。在此，我们以蜣螂为重点分类群，研究热带多样化景观对生物多样性保护的重要性。
该研究在12个多样化景观中开展，在每个研究的土地利用和覆盖类型（LUCC）——森林片段和走廊、咖啡种植园以及牧场中，沿着一条样带使用6个相距30米的陷阱诱捕器对蜣螂进行采样。我们在每个陷阱诱捕器中放置30克人类粪便作为诱饵，并敞开48小时。我们还测量了反映各研究类型结构差异的三个环境变量：树冠覆盖度、当地植被异质性和土壤含沙量。
我们收集了52种、共2695只蜣螂个体。我们观察到各类型之间在平均物种丰富度、丰度和生物量上存在显著差异，森林片段的值最高，森林走廊和咖啡种植园的值居中，牧场的值最低。关于群落结构，我们在各类型之间也发现了显著差异。树冠覆盖度是解释蜣螂物种丰富度、丰度、生物量和群落结构变化的唯一变量。在所有研究景观中，空间周转率的相对重要性大于嵌套性导致的组分。
本研究评估了多样化热带景观中蜣螂群落的生态模式，突出了这些景观对热带生物多样性保护的重要性。然而，我们鼓励对已经碎片化的景观进行多样化管理，或将其作为当前保护措施（如保护自然栖息地和建立保护区）的补充举措。
