Temporal variation in the abundance and richness of foliage-dwelling ants mediated by extrafloral nectar

Plants bearing extrafloral nectaries (EFNs) are common in the Brazilian cerrado savanna, where climatic conditions having marked seasonality influence arboreal ant fauna organization. These ant-plant interactions have rarely been studied at community level. Here, we tested whether: 1) EFN-bearing plants are more visited by ants than EFN-lacking plants; 2) ant visitation is higher in the rainy season than in dry season; 3) plants producing young leaves are more visited than those lacking young leaves in the rainy season; 4) during the dry season, plants with old leaves and flowers are more visited than plants with young leaves and bare of leaves or flowers; 5) the composition of visiting ant fauna differs between plants with and without EFNs. Field work was done in a cerrado reserve near Uberlândia, MG State, Brazil, along ten transects (total area 3,000 m2), in the rainy (October-January) and dry seasons (April-July) of 2010-2011. Plants (72 species; 762 individuals) were checked three ...具花外蜜腺（extrafloral nectaries, EFNs）的植物在巴西塞拉多稀树草原（cerrado savanna）中十分常见，该区域气候具有显著季节性，深刻影响着树栖蚂蚁类群的群落组织模式。这类蚁植交互关系在群落尺度上的相关研究仍较为匮乏。本研究旨在检验以下5个假说：1）具花外蜜腺的植物相较于无花外蜜腺的植物，会受到蚂蚁更多频次的造访；2）蚂蚁的造访率在雨季高于旱季；3）雨季中，萌发新叶的植物相较于无新叶的植物，会受到更多蚂蚁造访；4）旱季时，带有老叶与花的植物相较于带有新叶、无叶或无花的植物，会受到更多蚂蚁造访；5）具花外蜜腺与无花外蜜腺的植物，其造访蚂蚁类群的组成存在显著差异。 本研究的野外调查工作于2010-2011年开展，实验地点位于巴西米纳斯吉拉斯州（MG）乌贝兰迪亚附近的塞拉多保护区内，沿10条样带设置样地（总面积3000平方米），覆盖雨季（10月—次年1月）与旱季（4月—7月）两个时段。本次研究共调查72个物种、762株植物个体，每株均接受了三次……