DOI: 10.5061/dryad.msbcc2g89
title: N dynamics of leaf and root litter decomposition

description: Litter nitrogen (N) release during decomposition crucially influences
 ecosystem N cycling and the amount of N available to plants and other soil
 organisms. However, the role of initial litter traits in affecting
 patterns of temporal N release from litters and determining the fate of N
 in the soil is still poorly understood. Here, we measured litter N release
 during the 12-month decomposition of 15N-labelled leaf and root litters of
 12 common Mediterranean herbaceous species. We further traced the fate of
 N during decomposition of the litters into the soil and measured the
 inorganic N content in the soil solution as well as total N in the
 particulate (POM) and mineral-associated organic matter (MAOM) fractions
 at the end of the incubation. While most litters exhibited a very rapid
 initial N release, they were also quite variable in their N dynamics. As
 such they differed in the quantity and temporal patterns of N release, the
 accumulation of inorganic N in the soil solution, as well as in the
 incorporation of N in stable soil organic matter (SOM) fractions during
 decomposition. This variability was driven by differences in initial
 litter chemistry, particularly N, but also P and Mn, and litter C leachate
 concentrations. These and other traits (including water soluble compounds
 and lignin concentrations) explained up to 81% of the variance in N
 release rate, 48% for N accumulation in the soil solution, 57% for N
 entering the soil POM and 55% for MAOM fraction. Synthesis: We identified
 litter traits and litter types (root versus leaf) with afterlife effects
 on N cycling in soils and important implications for ecosystem
 functioning. Highly decomposable litters (typically high-N; including most
 leaf litters) generally support a fast N release through mineralisation,
 thereby the immediate supply of N to plants, but also potentially higher
 losses from the system, and long-term storage as MAOM-N, likely within
 microbial resynthesis products. In contrast, poorly decomposable litters
 (typically low-N; including most root litters) promote longer and weaker N
 release and foster N retention via lower N losses and increased POM-N
 formation.
description: # Data on N Dynamics of Leaf and Root Litter Decomposition
 [https://doi.org/10.5061/dryad.msbcc2g89](https://doi.org/10.5061/dryad.msbcc2g89) ## Description of the data and file structure This repository contains three datasets generated for the study entitled: **The afterlife effects of leaf and root litter traits on soil N cycling** (Accepted in *Journal of Ecology*) In this experiment, we used *15*N-labeled leaf and root litters from 12 common Mediterranean herbaceous species to explore (i) how initial litter chemistry influences litter mass loss and nitrogen (N) release during 12 months of decomposition and (ii) how the released N partitions into soil inorganic N pools and stable soil organic matter (SOM) fractions. The three datasets included are: 1. **`data_initial_traits`**: Initial chemical and stoichiometric traits of the litters. 2. **`data_decomposition`**: Time-series measurements of litter mass loss, litter N and C changes, and resin-captured inorganic N. 3. **`data_soil_fractions`**: Allocation of litter-derived N into soil particulate (POM) and mineral-associated (MAOM) organic matter fractions at the end of the experiment. --- ### **Experimental and Analytical Notes** Please check Wambsganss et al., 2025, Journal of Ecology for details on the material and methods.  ### Files and variables **File:** `data_initial_traits.xlsx` **Description:** * Provides the initial litter traits measured before decomposition began. **Variables:** * **litter type** (leaf or root) * **species** (scientific name) * **litter ID** * **plant functional type / group** * **initial litter mass (g)** (dry mass at start) * **initial litter C (%), N (%), P (%),** plus other elements (e.g., Mn, Ca, Mg) * **initial litter lignins (mg/g), cellulose (mg/g), hemicellulose (mg/g), tannins (mg/g)** * **initial litter solubles (mg/g)** or **leachate** data (C, N, P mg/g) * **initial 15N (at-%)** (atom percent *15*N for labeled litters) **File:** `data_decomposition.xlsx` **Description:** * Contains time-series (multiple harvests over 12 months) data on litter mass remaining, changes in litter C and N, soil N concentrations, and inorganic nutrients captured by ion-exchange resins. * Each row represents a harvest event from a given pot (with a unique pot ID and replicate ID). * Note: **NA's** may indicate data that are **not available** (i.e., missing data that were expected but could not be collected due to problems during the experiment) or data that are **not applicable** such in the case of the control soil samples (e.g., info on functional group or values for litter mass do not apply for the control soil samples).  **Variables:** * **pot ID** (unique identifier for each microcosm/pot) * **litter type** (leaf or root) * **species** * **harvest ID** & **harvest time** (indicates sampling time point) * **soil C (%)**, **soil N (%)**, **soil 13C (at-%), soil 15N (at-%)** * **resin N-NH4 (mg/l)**, **resin N-NO3 (mg/l)**, **resin P (mg/l)**, plus total g captured (e.g., **resin NH4 (g)**) * **litter mass (%)** or **litter mass (g)** remaining * **litter C (%)**, **litter N (%)** at harvest * **remaining litter N (g)**, **remaining litter C (g)** * **initial litter N (g)**, **initial litter C (g)** (link to `data_initial_traits`) * **litter N remaining (% of initial mass)**, **litter C remaining (% of initial mass)** **File:** `data_soil_fractions.xlsx` **Description:** * Provides data on the final accumulation of litter-derived N in soil organic matter (SOM) fractions after 12 months, specifically in the mineral-associated (MAOM) and particulate (POM) fractions. * Each row corresponds to a particular pot, replicate, and litter treatment at the end of the incubation. **Variables:** * **litter type** (leaf or root) * **treatment** * **species** * **pot ID** & **replicate ID** (links to `data_decomposition`) * **litter-derived soil N (mg/g)** (concentration of litter-derived N in the soil) * **MAOM-N (mg/g)**, **POM-N (mg/g)** (N concentrations in the mineral-associated and particulate organic matter fractions) * **litter-derived soil N (g)**, **MAOM-N (g)**, **POM-N (g)**  ## Code/software Excel or RStudio