DOI: 10.5061/dryad.8h4v0
title: Data from: Quantifying the factors affecting leaf litter decomposition across a tropical forest disturbance gradient

description: Deforestation and forest degradation are driving unprecedented declines in
 biodiversity across the tropics, and understanding the consequences of
 these changes for ecosystem functioning is essential for human well-being.
 Forest degradation and loss alter ecosystem functioning through changes in
 species composition and abiotic conditions. However, the consequences of
 these changes for heterospecific processes are often poorly understood.
 Leaf litter decomposition is a major source of atmospheric carbon and
 critical for carbon and nutrient cycling. Through a highly replicated
 litter-bag experiment (3360 bags), we quantified the effects of litter
 quality, decomposer functional diversity and seasonal precipitation regime
 on litter decomposition along a tropical disturbance gradient in SW China.
 In addition, using soil and litter from sites selected from across the
 disturbance gradient, we established replicated litter-bed treatments and
 exposed these to a gradient of simulated canopy cover in a shade-house.
 Across the landscape, mass loss from litter-bags after 12 months varied
 from 7% to 98%. Even after 12 months, litter-bags installed at the
 beginning of the dry season had much lower mass loss than those installed
 at the beginning of the wet season. As expected, litter quality and faunal
 exclusion had substantial effects on decomposition rates. Decomposition
 rates declined along the disturbance gradient from mature forest, through
 regenerating forest to open land, although the effect size was strongly
 dependent on installation season. The effect of excluding meso- and
 macro-invertebrates increased with increasing forest degradation, whereas
 the effect of litter quality declined. Results from the shade-house
 experiment strongly suggested that forest degradation effects were driven
 predominantly by changes in micro-climatic conditions resulting from
 increased canopy openness. To better model the impacts of anthropogenic
 global change on litter decomposition rates, it will be important to
 consider landscape scale processes, such as forest degradation.
description: Data_landscape
 experimentData from landscape
 experimentData_mesocosm
 experimentData from mesocosm
 experimentData_environmental
 factorsLandscape experiment
 data combined with soil PCA axes and vegetation NMDS axes
 valuesAbundance
 data_vegetationVegetation abundance
 data. Species occurred in only one plots are not
 included.Temperature_landscapeTemperature data from climatic station and microclimatic loggers installed across the landscapeTemperature_shade houseTemperature data from climatic station and microclimatic loggers installed in the shade-houseSoil moisture and relative humidity_landscapeSoil moisture and relative humidity data collected from microclimatic loggers installed across the landscapeSoil moisture and relative humidity_shade houseSoil moisture and relative humidity data collected from microclimatic loggers installed in the shade-housePAR_median_plotPhotosynthetic active radiation (PAR) for landscapePAR_median_shade housePhotosynthetic active radiation (PAR) for shade-houseR script_landscape experimentR script for the analysis of data from landscape experimentR script_mesocosm experimentR script for the analysis of data from mesocosm experimentR script_environment_factorsR script for the analysis of data from landscape experiment using environmental variablesR script_graphsR script for plotting figuresOrdinationR script for vegetation and soil ordinations and related figuresClimate and microclimate scriptsR scripts for the microclimatic figures in appendices