Dataset on soil physical and chemical properties under barley – pea intercropping and monoculture systems in Dundee, Scotland, 2022-2023

Summary This dataset contains measurements of soil physical and chemical properties at Balruddery Farm, Dundee, Scotland. Soil samples were collected periodically between 2022 – 2023 at different crop growth stages from upper (< 5 cm) and lower (5 – 30 cm) topsoil depths. These data were collected from a field experiment study designed to examine the short-term effects of barley – pea intercropping systems on soil properties. Specifically, it involved two barley – pea intercropping systems and their respective monocultures. The experiment was carried out at Balruddery Farm, Dundee, Scotland which belongs to the James Hutton Institute in partnership with the University of Aberdeen. The work was supported by the Scottish Government’s Hydro Nation Scholars Programme through the Scottish Funding Council (Grant number: SF10247-10). Provenance & quality Soil samples were analysed for chemical properties at the University of Aberdeen, while soil physical properties were analysed at the James Hutton Institute, Dundee. Instruments were used following standard calibration steps and results were quality controlled. Temporal coverage: February 2022 – September 2023. Related document: Journal paper associated with this dataset can be found at https://doi.org/10.1002/agj2.70275 Supporting documentation Cropping systems consisted of three monocultures and two barley-pea intercropping systems involving two barley cultivars and one pea cultivar (Table 1). Barley cultivars were 1) Laureate, a high-yielding barley cultivar, and 2) KWS Sassy, a water stress-tolerant cultivar, while the pea cultivar was LG Stallion (Table 1). Soil was sampled on six occasions over the two years for analysis of the following soil parameters: total soil carbon and nitrogen, volumetric water content (VWC), water retention, dry bulk density, porosity, macroporosity and penetration resistance. There were three sampling campaigns in 2022: pre-tillage (PT) on 29 March, mid-season (MS) on 28 June, and post-harvest (PH) on 22 September; and an additional three in 2023: PT on 21 February, MS on 20 June and PH on 19 September. Samples were collected from location: 56.485°N, -3.114°W. Table 1: Description of cropping systems ID Description of cropping systems BL Barley (var. Laureate) Monoculture BL&PS Barley (var. Laureate) and Pea (var. LG Stallion) Intercropping BS Barley (var. KWS Sassy) Monoculture BS&PS Barley (var. KWS Sassy) and Pea (var. LG Stallion) Intercropping PS Pea (var. LG Stallion) Monoculture Soil cores were weighed at field condition, saturated for at least 12 hours, weighed again, and then placed on ceramic suction plates for at least 10 days to equilibrate the soil to a matric potential of -50kPa, prior to reweighing to obtain water retention. Samples were then measured for soil penetration resistance with a universal test frame penetrometer (Instron model 5566; Instron, MA, USA) mounted with a 50-N load cell accurate to 2 mN at maximum load. Each soil core was penetrated with a 1 mm diameter needle at 30° cone angle to a depth of 15 mm at 0.75 mm increments from the soil surface at a rate of 4 mm min−1. Penetration resistance between 4.5 mm and 9.8 mm depth was averaged as the sample penetration resistance. To bulk density (g cm-3), the soil from the cores was reweighed after oven drying at 105 °C for 24 h. Data are expressed as mass of oven-dried soil per volume of cylindrical core. Soil water content was determined gravimetrically (g g-1) as mass of water in the soil sample per mass of the oven-dried soil and converted to volumetric water content (%) by using the bulk density of the soil sample. Porosity (%) was determined from bulk density, assuming 2.65 g cm-3 as particle density. Thereafter, cores were sieved to 2 mm and the mass of non-soil particles that did not pass the 2 mm sieve is regarded as the stone mass. For chemical properties, samples were sieved using a 2 mm sieve, dried in an oven at 105 °C for 24 h and ball milled before using Dumas dry combustion procedure with a flash combustion elemental analyser (model: NA 2500; manufacturer: Carlo Erba) to obtain total C concentration (g kg-1) and total N concentration (g kg-1).数据集摘要 本数据集包含苏格兰邓迪巴勒鲁迪农场的土壤物理与化学性质测量数据。2022年至2023年间，研究人员在不同作物生育期，分别从上层（<5cm）与下层（5~30cm）表土层采集土壤样品。 本数据源自一项田间试验研究，旨在探究大麦-豌豆间作系统对土壤性质的短期影响。试验共设置2种大麦-豌豆间作系统及其对应的单作体系，实验地点位于苏格兰邓迪的巴勒鲁迪农场，由詹姆斯·赫顿研究所（James Hutton Institute）与阿伯丁大学（University of Aberdeen）合作开展，研究得到苏格兰资助委员会（Scottish Funding Council）下属苏格兰政府水利国家学者计划（Scottish Government’s Hydro Nation Scholars Programme）资助（项目编号：SF10247-10）。 ## 来源与质量控制 土壤化学性质分析在阿伯丁大学完成，土壤物理性质分析则在詹姆斯·赫顿研究所邓迪分部进行。所有仪器均按照标准校准流程进行校准，测试结果经过质量管控。 时间覆盖范围：2022年2月—2023年9月。 相关文献：本数据集对应的期刊论文可通过https://doi.org/10.1002/agj2.70275获取。 ## 辅助说明材料 本试验种植系统包含3种单作模式与2种大麦-豌豆间作模式，涉及2个大麦品种与1个豌豆品种（见表1）。其中大麦品种分别为：1）拉瑞特（Laureate），高产大麦品种；2）KWS Sassy，耐旱品种；豌豆品种为LG Stallion（见表1）。 本研究在两年内共开展6次土壤采样，以分析以下土壤参数：土壤总碳与总氮含量、体积含水量（volumetric water content, VWC）、持水性、干容重、孔隙度、大孔隙度与贯入阻力。2022年共3次采样：3月29日翻耕前（pre-tillage, PT）、6月28日生育中期（mid-season, MS）与9月22日收获后（post-harvest, PH）；2023年共3次采样：2月21日翻耕前、6月20日生育中期与9月19日收获后。采样地点坐标为56.485°N，-3.114°W。 表1：种植系统说明 ID 种植系统说明 BL 拉瑞特（Laureate）大麦单作 BL&PS 拉瑞特（Laureate）大麦与LG Stallion豌豆间作 BS KWS Sassy大麦单作 BS&PS KWS Sassy大麦与LG Stallion豌豆间作 PS LG Stallion豌豆单作 土壤环刀样品先在田间状态下称重，经饱和处理至少12小时后再次称重，随后置于陶瓷吸力板上平衡至少10天，使土壤基质势达到-50kPa，再次称重以获取土壤持水性数据。之后使用搭载50N测力传感器（最大载荷下精度可达2mN）的英斯特朗（Instron）5566型万能框架式贯入仪（Instron公司，美国马萨诸塞州）测定土壤贯入阻力：以直径1mm、锥角30°的探针，以4mm/min的速率，按0.75mm的增量从土面刺入15mm深度，取4.5mm至9.8mm深度区间的贯入阻力平均值作为样品的贯入阻力值。 干容重（单位：g·cm⁻³）的测定方法为：将环刀内的土壤样品置于105℃烘箱中烘干24小时后称重，以烘干土质量除以圆柱环刀的体积得到。土壤重量含水量采用重量法测定（单位：g·g⁻¹），即土壤样品中水的质量与烘干土质量的比值，再通过土壤容重换算为体积含水量（%）。孔隙度（%）通过干容重计算得出，假设土壤颗粒密度为2.65 g·cm⁻³。随后将土样过2mm筛，未通过筛孔的非土壤颗粒质量记为石砾质量。 对于土壤化学性质，土样先经2mm筛筛分，置于105℃烘箱中烘干24小时后进行球磨处理，随后采用杜马斯干式燃烧法，通过闪燃元素分析仪（型号：NA 2500；制造商：Carlo Erba）测定总碳浓度（单位：g·kg⁻¹）与总氮浓度（单位：g·kg⁻¹）。