Soil carbon maintained by perennial grasslands over 30 years but lost in field crop systems in a temperate Mollisol

To mitigate climate change, some seek to store carbon from the atmosphere in agricultural soils. However, our understanding about how agriculture affects soil organic carbon is muddied by studies (1) lacking longitudinal data, (2) ignoring bulk density changes, or (3) sampling only surface soils. To better understand soil organic carbon trends, here we measured changes over 30 years in density-corrected, full-soil-depth (90 cm) soil organic carbon stocks under 6 cropping systems and a restored prairie in a Mollisol of southern Wisconsin, USA. Cash-grain systems and alfalfa-based systems lost soil organic carbon. Prairie and rotationally-grazed pasture maintained soil organic carbon. Average soil organic carbon losses for cash-grain and alfalfa-based systems were −0.82 (±0.12) and −0.64 (±0.17) Mg C ha-1 yr-1, respectively. Sensitivity analysis showed that incomplete methodologies overestimated soil organic carbon improvements. Our findings using more comprehensive methods demonstrate th..., , , # Soil carbon maintained by perennial grasslands over 30 years but lost in field crop systems in a temperate Mollisol [https://doi.org/10.5061/dryad.b8gtht7mv](https://doi.org/10.5061/dryad.b8gtht7mv) This dataset contains percent carbon, percent nitrogen, and soil bulk density data for samples from the Wisconsin Integrated Cropping Systems Trial (WICST) collected in 1989, 2009, and 2019. WICST compares six cropping systems and a restored native grassland common to the Upper Midwest United States of America in a randomized complete block design. This data was collected to measure changes in soil organic carbon stocks over time as a result of different cropping systems and land use. ## Description of the data and file structure This data is available as an Excel spreadsheet and associated Microsoft Word document. In these, there is a full description of the experiment and data. ## Code/Software SAS code used to analyze the data using a linear mixed effects model is available in the...为应对气候变化，部分研究尝试将大气中的碳封存于农业土壤中。然而，现有研究存在三大局限，导致我们对农业如何影响土壤有机碳的认知仍较为模糊：一是缺乏纵向观测数据，二是未考虑土壤容重变化，三是仅采集表层土壤样本。 为更清晰地厘清土壤有机碳的变化趋势，本研究在美国威斯康星州南部的软土（Mollisol）中，针对6种种植系统与1个恢复草原样地，开展了为期30年的密度校正全土层（90 cm）土壤有机碳储量监测。结果显示，商品谷物种植系统与苜蓿基种植系统的土壤有机碳出现流失；而恢复草原与轮牧牧场的土壤有机碳得以维持。商品谷物与苜蓿基系统的年均土壤有机碳流失量分别为-0.82（±0.12）与-0.64（±0.17）Mg C ha⁻¹ yr⁻¹。敏感性分析表明，采用不完整研究方法会高估土壤有机碳的提升效果。本研究采用更为全面的方法所得出的结果证实…… # 温带软土中多年生草地可维持土壤碳储量 而大田作物系统则出现碳流失 https://doi.org/10.5061/dryad.b8gtht7mv 本数据集包含1989年、2009年与2019年采集自威斯康星州综合种植系统试验（Wisconsin Integrated Cropping Systems Trial, WICST）的土壤碳占比、氮占比与土壤容重数据。WICST采用随机完全区组设计，对比了美国中西部北部常见的6种种植系统与1个恢复原生草原样地。本数据旨在量化不同种植系统与土地利用方式下，土壤有机碳储量随时间的变化情况。 ## 数据与文件结构说明 本数据以Excel电子表格与配套的Microsoft Word文档形式提供，其中详细记录了实验方案与数据信息。 ## 代码与软件 用于采用线性混合效应模型开展数据分析的SAS代码可在……中获取。