Data from: Diversity and composition of tropical butterflies along an Afromontane agricultural gradient in the Jimma Highlands, Ethiopia

Afromontane landscapes are typically characterized by a mosaic of smallholder farms and the biodiversity impacts of these practices will vary in accordance to local management and landscape context. Here, we assess how tropical butterfly diversity is maintained across an agricultural landscape in the Jimma Highlands of Ethiopia. We used transect surveys to sample understory butterfly communities within degraded natural forest, semi-managed coffee forest (SMCF), exotic timber plantations, open woodland, croplands and pasture. Surveys were conducted in 29 one-hectare plots and repeated five times between January and June 2013. We found that natural forest supports higher butterfly diversity than all agricultural plots (measured with Hill's numbers). SMCF and timber plantations retain relatively high abundance and diversity, but these metrics drop off sharply in open woodland, cropland and pasture. SMCF and timber plantations share the majority of their species with natural forest and support an equivalent abundance of forest-dependent species, with no increase in widespread species. There was some incongruence in the responses of families and sub-families, notably that Lycaenidae are strongly associated with open woodland and pasture. Adult butterflies clearly utilize forested agricultural practices such as SMCF and timber plantations, but species diversity declines steeply with distance from natural forest suggesting that earlier life-stages may depend on host plants and/or microclimatic conditions that are lost under agricultural management. From a management perspective, the protection of natural forest remains a priority for tropical butterfly conservation, but understanding functioning of the wider landscape mosaic is important as SMCF and timber plantations may act as habitat corridors that facilitate movement between forest fragments.非洲山地（Afromontane）景观通常以小农农场镶嵌格局为典型特征，此类农业实践对生物多样性的影响会随当地管理方式与景观背景的差异而发生变化。本研究针对埃塞俄比亚吉马高原的农业景观，探究热带蝴蝶多样性的维持机制。本研究采用样线调查法（transect surveys），对退化天然林、半管理咖啡林（SMCF）、外来用材人工林、开阔林地、农田及牧场内的林下蝴蝶群落进行采样。调查共设置29块1公顷样地，并于2013年1月至6月间重复开展5次。研究发现，相较于所有农业样地，天然林的蝴蝶多样性更高（以希尔指数（Hill's numbers）衡量）。半管理咖啡林与用材人工林的蝴蝶个体丰度与多样性均维持在较高水平，但在开阔林地、农田及牧场中，这两项指标均出现显著下降。半管理咖啡林与用材人工林与天然林共享绝大多数蝴蝶物种，且其依赖森林的物种丰度与天然林相当，并未出现广布物种占比上升的情况。不同蝴蝶科与亚科的响应模式存在一定差异，其中灰蝶科（Lycaenidae）与开阔林地和牧场呈现显著的正相关关系。成虫蝴蝶显然可利用半管理咖啡林、用材人工林等农林生境，但物种多样性随与天然林距离的增加而急剧下降，这表明蝴蝶的早期发育阶段可能依赖宿主植物或微气候条件，而这些条件在农业管理过程中已丧失。从管理角度而言，保护天然林仍是热带蝴蝶保育的首要任务，但理解整体景观镶嵌格局的生态功能同样至关重要——半管理咖啡林与用材人工林可作为生境廊道，促进森林片段间的物种扩散。