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Land-use change and agricultural intensification can strongly affect biodiversity in agricultural landscapes. Although many studies investigate management impacts, data on the long-term change of species communities in agroecosystems are scarce., We analysed the long-term change in diversity and composition of ant communities in cacao agroforestry systems in Central Sulawesi, Indonesia and attempted to disentangle the driving factors of this change. Ant communities were resampled in 2009 from sites for which previous surveys had been conducted either in 2001 (the rainforest-poor Palolo region) or 2003 (the rainforest-rich Kulawi region) using insecticide fogging., Ant community composition changed significantly over time in Palolo and Kulawi. The change in ant species richness differed between regions. Species richness increased in Kulawi, probably due to the increasing availability of nest sites and microhabitats as trees grow larger and older. In the Palolo region, species richness decreased, suggesting that the high local intensification and landscape-wide changes may have counteracted the effects of tree age. Changes in ant communities over time were significant, but were more difficult to explain than expected, despite clear difference in management changes within and between regions., The findings suggest that the landscape-scale differences between the two study regions play a more important role for species diversity and its composition than changes in local management. This highlights the importance of long-term studies across contrasting landscapes for better understanding the consequences land-use intensification has on tropical biodiversity. [ABSTRACT FROM AUTHOR]

Management intensification in cultivated, tropical forests drives changes in the microclimate that can threaten native forest flora and fauna. In this study, we use epiphytic bryophytes, known to be sensitive to microclimatic changes due to their lack of a protective cuticle and the exposed habitat, to investigate the predictive power of microclimate for changes in species richness and composition. Bryophytes were sampled from understory trees in natural forest and cacao (Theobroma cacaoL.) trees in two types of cacao agroforests (natural shade trees and planted shade trees) in Central Sulawesi, Indonesia. The microclimate in the agroforests was characterised by low air humidity and high air temperature during the afternoon. Bryophyte species richness did not differ between habitat types but species composition changed markedly from the natural forest to the cacao agroforests. Although no correlation between species richness and microclimate values could be found, a series of matrix-based analyses revealed a significantly positive relationship between similarities in species composition and in maximum values for temperature and minimum values for humidity, which suggests that microclimatic changes are a good predictor for high turnover of bryophyte community composition from natural forests to cacao agroforests. [ABSTRACT FROM AUTHOR]

Forest disturbance and transformations into agricultural land alter tropical landscapes at drastic rates. Here, we investigate bryophyte assemblages on trunk bases in natural forest, selectively logged forest and cacao agroforests that are shaded by remnants of natural forest in Central Sulawesi. Overall, bryophyte richness per site did not differ between forest types. However, mosses and liverworts reacted differently in that moss richness was lowest in cacao agroforests, whereas liverwort communities were equally rich in all forest types. In terms of cover, mosses remained unaffected while liverwort cover decreased significantly in disturbed forest. Species composition of bryophytes clearly changed in cacao agroforests as compared to natural forests and selectively logged forests. In particular some drought-sensitive species were rare or absent in cacao agroforests and were replaced by drought-tolerant ones, thus underlining the importance of microclimatic changes. Moreover, differences in bryophyte species composition between large and small trees were only pronounced in cacao agroforests, presumably due to concomitant changes in stemflow of precipitation water. In conclusion, the bryophyte assemblages of selectively logged forests and cacao agroforests were as rich as in natural forest, but species turn-over was particularly high towards cacao agroforests probably due to microclimatic changes. Maintenance of shade cover is crucial to the conservation of the drought-sensitive forest species. [Copyright &y& Elsevier]