Factors influencing fine root decomposition rate in response to nitrogen addition vary across root characteristics

Nitrogen (N) deposition strongly affects litter decomposition and nutrient release , thereby reshaping carbon cycling in terrestrial ecosystems. Although most studies have focused on above-ground litter, the effects of N addition on fine root decomposition and their underlying drivers, particularly across different root characteristics, remain poorly understood. We synthesized a meta-analysis of 144 observations from 30 studies to quantify the response of fine root decomposition rates to N addition and to identify the key factors that regulate these responses across root characteristics. On average, N addition reduced fine root decomposition rates and mass loss by 8.52% and 6.24%, respectively. Negative responses to N addition were most pronounced in roots ≤2 mm in diameter and in first- and second-order roots. Soil microbial biomass N and clay content were the dominant drivers of these responses in roots ≤2 mm. Within different root characteristics, soil microbial biomass N and soil N ..., , # Factors influencing fine root decomposition rate in response to nitrogen addition vary across root characteristics

Dataset DOI: [10.5061/dryad.x3ffbg7xm](10.5061/dryad.x3ffbg7xm)

## Description of the data and file structure

144 observations on the responses of fine root decomposition rate to nitrogen addition from 30 peer-reviewed publications at the global scale were collected.

### Files and variables

#### File: Fine_root_decomposition_Wang_et_al.FE.csv

**Description:**

NA indicates not available; Null indicates not applicable.

##### Variables

* Lon: Longitude of site in decimal degrees.
* Lat: latitude of site in decimal degrees.
* MAT: Mean annual temperature in degrees ℃
* MAP: Mean annual precipitation in mm
* Ecosystem_type: Ecosystem types of plants include forest, grassland, and wetland
* Climatic_zone: Climatic zones of plants  include Subtropical, tropical and temperate
* MYC: Mycorrhizal types include ectomycorrhizal (EM) and arbuscular mycorrhizal (AM)
* Leaf_for...,

氮（N）沉降会显著影响枯落物分解与养分释放，进而重塑陆地生态系统的碳循环。尽管多数研究聚焦于地上枯落物，但氮添加对细根分解的影响及其潜在驱动因子，尤其是不同根属性下的差异，仍有待深入阐明。本研究对30项研究的144条观测数据开展了荟萃分析，以量化细根分解速率对氮添加的响应，并识别调控不同根属性下该响应的关键因子。平均而言，氮添加使细根分解速率和质量损失分别降低8.52%和6.24%。氮添加的负向响应在直径≤2mm的根以及一级和二级根中最为显著。对于直径≤2mm的根，土壤微生物生物量氮和黏粒含量是调控其响应的主导驱动因子。在不同根属性下，土壤微生物生物量氮与土壤氮…… ，# 氮添加下细根分解速率的影响因子随根属性而异

数据集DOI：[10.5061/dryad.x3ffbg7xm](10.5061/dryad.x3ffbg7xm)

## 数据与文件结构说明
本数据集收集了全球范围内30篇同行评议文献中的144条关于细根分解速率对氮添加响应的观测数据。

### 文件与变量
#### 文件：Fine_root_decomposition_Wang_et_al.FE.csv
**文件说明：**
NA表示数据不可用；Null表示数据不适用。

##### 变量
* 经度（Lon）：站点经度，单位为十进制度数。
* 纬度（Lat）：站点纬度，单位为十进制度数。
* 年均温（MAT）：年均气温，单位为摄氏度（℃）。
* 年均降水量（MAP）：年均降水量，单位为毫米（mm）。
* 生态系统类型（Ecosystem_type）：植物所属生态系统类型，包括森林、草原与湿地。
* 气候带（Climatic_zone）：植物所处气候带，包括亚热带、热带与温带。
* 菌根类型（MYC）：菌根类型包括外生菌根（ectomycorrhizal, EM）和丛枝菌根（arbuscular mycorrhizal, AM）。
* 叶部相关变量（Leaf_for...）：原文未完整展示。