External aluminium supply regulates photosynthesis and carbon partitioning in the Al-accumulating tropical shrub Melastoma malabathricum

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Tripartite symbioses regulate plant–soil feedback in alder

ACKNOWLEDGEMENTS We thank the National Trust for Scotland for access to the Crathes Estate. This work was funded by the Natural Environment Research Council (ref NE/M015653/1) and a Ramon Areces Fellowship to A.A. D.J. receives partial funding from the N8 AgriFood programme. We thank Filipa Cox for a critical read of the manuscript.Peer reviewedPublisher PD

Land use not litter quality is a stronger driver of decomposition in hyperdiverse tropical forest

In hyperdiverse tropical forests, the key drivers of litter decomposition are poorly understood despite its crucial role in facilitating nutrient availability for plants and microbes. Selective logging is a pressing land use with potential for considerable impacts on plant-soil interactions, litter decomposition, and nutrient cycling. Here, in Borneo's tropical rainforests, we test the hypothesis that decomposition is driven by litter quality and that there is a significant "home-field advantage," that is positive interaction between local litter quality and land use. We determined mass loss of leaf litter, collected from selectively logged and old-growth forest, in a fully factorial experimental design, using meshes that either allowed or precluded access by mesofauna. We measured leaf litter chemical composition before and after the experiment. Key soil chemical and biological properties and microclimatic conditions were measured as land-use descriptors. We found that despite substantial differences in litter quality, the main driver of decomposition was land-use type. Whilst inclusion of mesofauna accelerated decomposition, their effect was independent of land use and litter quality. Decomposition of all litters was slower in selectively logged forest than in old-growth forest. However, there was significantly greater loss of nutrients from litter, especially phosphorus, in selectively logged forest. The analyses of several covariates detected minor microclimatic differences between land-use types but no alterations in soil chemical properties or free-living microbial composition. These results demonstrate that selective logging can significantly reduce litter decomposition in tropical rainforest with no evidence of a home-field advantage. We show that loss of key limiting nutrients from litter (P & N) is greater in selectively logged forest. Overall, the findings hint at subtle differences in microclimate overriding litter quality that result in reduced decomposition rates in selectively logged forests and potentially affect biogeochemical nutrient cycling in the long term

Logging and soil nutrients independently explain plant trait expression in tropical forests

We acknowledge financial support by the UK Natural Environment Research Council (NE/K016253/1), with additional support through an ERC Advanced Investigator Award to YM (GEM-TRAIT; 321131). We are indebted to the Sabah Biodiversity Council, Yayasan Sabah, the Maliau Basin and Danum Valley Management Committees, the Institute for Tropical Biology and Conservation at the University of Malaysia, Sabah, and the Sabah Forest Research Centre at Sepilok. We thank Glen Reynolds and the South East Asia Rainforest Research Partnership (SEARRP). This study was supported by funding from the Sime Darby Foundation to the Stability of Altered Forest Ecosystems (SAFE) Project. This project would not have been possible without the indispensable support from dozens of research assistants in Sabah. The support from Laura Kruitbos, Unding Jami, Lisa P. Bentley, Benjamin Blonder, Puikiat Hoo, Palasiah Jotan, Alexander Shenkin and Chun Xing Wong is gratefully acknowledged. We thank Bernadus Bala Ola, Bill McDonald, Alexander Karolus and MinSheng Khoo for species identification. This publication is a contribution from the UK NERC-funded Biodiversity And Land-use Impacts on Tropical Ecosystem Function (BALI) consortium (http://bali.hmtf.info) through its Human Modified Tropical Forests thematic programme.Peer reviewedPostprin