Data and R code for Flow intermittence alters carbon processing in rivers through chemical diversification of leaf litter

Complete
dataset and R code to replicate results from the paper "Flow intermittence
alters carbon processing in rivers through chemical diversification of leaf
litter" published in Limnology and Oceanography Letters.

See
metadata.pdf file for description of the experimental design and methods and
Rcode_readme.txt for explanations about the R code used to get results and
figures of the manuscript.

General
description:

This work
compiles laboratory and field experiments used to test the hypothesis that
environmental heterogeneity during the drying phase of intermittent rivers can
promote a chemical diversification of leaf litter, and therefore alter its
aquatic decomposition after flow resumption. In a first experimental phase, we exposed
leaf litter (alder, Alnus glutinosa) to various environmental conditions in the
laboratory simulating typical habitats of drying rivers (dry riverbeds exposed
to solar radiation, wet and shaded riverbeds, different types of isolated
pools, etc.). Afterwards, we measured the leaf litter content in C, N, P, Ca,
Mg, K, and macromolecular organic C moieties by Fourier-transform infrared
spectroscopy (FTIR) to study the effect of preconditioning on leaf litter chemistry.

In a
second stage, we combined leaf litter from the different preconditioning
treatments to create leaf mixtures within a gradient of treatment richness
(from single treatments to mixtures of 2-, 4- and 6-treatments). We used fine and
coarse mesh-bags containing single treatments and leaf mixtures to measure leaf
decomposition in a river. To study aquatic decomposition, we measured leaf mass
loss, fungal biomass as ergosterol and shredder density. In parallel, we
incubated leaf litter in bottles in a respiration assay in the laboratory to
measure microbial respiration rates.

Finally,
we used the chemical traits measured in preconditioned leaves to estimate chemical
composition and diversity of all litterbags by using community-weighted means
and RaoQ diversity, respectively.