Extreme wetness reduces soil microbial residue carbon more substantially than extreme drought across grassland ecosystems

Soil microbial residue carbon (MRC) represents a significant component of soil carbon pools and regulates the response of soil carbon sequestration to precipitation changes. However, how soil MRC content responds to extreme drought and wetness, and the underlying mechanisms in regional grassland ecosystems, remains unclear. Here, we quantified the responses of soil MRC content to extreme drought and wetness, and identified the key drivers using a coordinated precipitation change experiment across nine alpine and temperate grassland ecosystems in China. Extreme drought (-50% precipitation) reduced MRC content by 8% on average. In contrast, extreme wetness (+50% precipitation) unexpectedly caused a pronounced 24% average decline in MRC content. Under extreme drought, reduced plant biomass inhibited soil MRC formation, and soil microbial N enzymes accelerated soil MRC decomposition. Moreover, wetter ecosystems exhibited greater losses of soil MRC, while drier ecosystems experienced a more ..., , # Data from: Extreme wetness reduces soil microbial residue carbon more substantially than extreme drought across grassland ecosystems

#### Data Description

Data.xlsx: Contains measurements of variables for each sample, along with the associated Site and Treatment.
Each row represents an individual sample (Sample), corresponding to one measurement or sampling event.
Each column represents a variable (Sample, Site, Treatment, pH...) describing sample attributes or measurements.

**Variable Descriptions**

3.1 Sample ID
Type: String
Description: Name of the sample.
Format Example: A1.1, A1.2...
Note: The letter (A–C) denotes the Treatment plot. The first digit (1-9) indicates the Site number. The last digit (1-3 or 4) indicates the Block number.

3.2 Site
Type: String
Description: Name of the sampling Site.
Example: Dangxiong...

3.3 Treatment
Type: String
Description: Experimental Treatment plot.
Examples: Control, -50%Pre, +50%Pre

3.4 Plant, Soil, Microbial variables
Type: Numeric
De...,

土壤微生物残体碳（MRC）是土壤碳库的重要组成部分，可调控土壤碳固存对降水变化的响应。然而，在区域草原生态系统中，土壤MRC含量如何响应极端干旱与极端湿润，以及其背后的潜在机制，目前仍不明晰。本研究依托中国9个高寒与温带草原生态系统的协同降水控制实验，量化了土壤MRC含量对极端干旱和极端湿润的响应，并识别了其关键驱动因子。极端干旱（降水减少50%）平均使MRC含量降低8%。与之相反，极端湿润（降水增加50%）却意外地使MRC含量平均显著下降24%。在极端干旱条件下，植物生物量的降低抑制了土壤MRC的形成，而土壤微生物氮酶则加速了土壤MRC的分解。此外，生态系统越湿润，土壤MRC的流失量越大，而干旱程度更高的生态系统则呈现出更为……
# 数据来源：《草原生态系统中极端湿润对土壤微生物残体碳的消减效应显著强于极端干旱》

#### 数据说明
Data.xlsx：包含各样本的变量测定值，以及对应的样地（Site）与处理组（Treatment）信息。每一行代表一个独立样本（Sample），对应一次测定或采样事件。每一列代表一个变量（Sample、Site、Treatment、pH等），用于描述样本属性或测定结果。

**变量说明**
3.1 样本编号（Sample ID）
类型：字符串型
描述：样本名称
格式示例：A1.1、A1.2等
备注：字母（A–C）代表处理样地，第一位数字（1-9）表示样地编号，最后一位数字（1-3或4）表示区组编号。
3.2 样地（Site）
类型：字符串型
描述：采样样地名称
示例：当雄（Dangxiong）
3.3 处理组（Treatment）
类型：字符串型
描述：实验处理样地类型
示例：对照组（Control）、-50%Pre（降水减少50%）、+50%Pre（降水增加50%）
3.4 植物、土壤、微生物变量
类型：数值型
描述：……