SLU long-term field experiments: The frame trial (R3-RAM56), crop and soil data from 1956 and onwards

The SLU long-term agricultural field experiments are a nationwide research infrastructure consisting of experiments in hydrological management, tillage, landscape ecology, plant nutrition, weed biology and control, cropping systems, and cropping systems in northern Sweden. They are used to study how crop rotations and cultivation measures in agriculture affect soil properties and crop yields in the long term, and the effect of weather and climate on the efficacy of these treatments. The experimental sites and the data collected in the long-term experiments are a valuable resource for research, teaching and consulting. The experiments are open for those who want to use data already collected or who want to do their own sampling. All long term experiments are funded by the NJ faculty and administered by an academic department, with the activities coordinated by a committee.

Twenty four long-term field experiments in plant nutrition and soil fertility are currently managed by the Department of Soil and Environment at the Swedish University of Agricultural Sciences. These experiments, starting as early as 1936 or as recently as 2010, are grouped into eight different experimental series that focus on themes such as agronomically-relevant factors including liming, long-term soil fertility, soil organic matter and soil biology. Plant and soil samples have been collected, measured for standard parameters, and archived since the start of the experiments, forming the basis of over 200 theses and papers across a broad range of disciplines.

The frame experiment is located at the Ultuna Campus at the Swedish University of Agricultural Sciences and has been ongoing since 1956. The aim of the experiment is to study the effect of different combinations of organic matter and nitrogen fertilization on soil organic matter content, yield level and crop nutrient content. This dataset contains values ​​for nutrient content in crops, soil and organic matter, and yields between 1956 and 2023. The data is provided as a single tsv file (RAM56_data.tsv), with an additional seven tsv files providing context. Physical data collected by researchers since the beginning of the experiment, together with plant and soil samples collected from a subset of time points during the experiment, are stored at the Swedish University of Agricultural Sciences.

瑞典农业科学大学（Swedish University of Agricultural Sciences，SLU）长期农田野外试验属于国家级研究基础设施，其试验内容涵盖水文管理、耕作措施、景观生态、植物营养、杂草生物学与防治、种植制度，以及瑞典北部的种植制度相关试验。该设施用于长期研究农业领域的轮作与栽培措施如何影响土壤性状与作物产量，以及天气与气候对上述措施实施效果的影响。长期试验的试验场地与采集得到的数据，是支撑科研、教学与咨询服务的宝贵资源。本试验面向所有希望使用已采集数据或自主开展采样工作的人员开放。所有长期试验均由NJ学院资助，由学术院系进行管理，相关活动由委员会统筹协调。

目前，瑞典农业科学大学土壤与环境系负责管理24项植物营养与土壤肥力相关的长期野外试验。这些试验最早始于1936年，最晚始于2010年，被划分为8个不同的试验系列，研究主题涵盖农艺相关因素，包括石灰施用、长期土壤肥力、土壤有机质与土壤生物学。自试验启动以来，科研人员已采集植物与土壤样本，测定其标准参数并进行归档，这些样本与数据已成为200余篇学位论文与学术论文的研究基础，研究领域覆盖众多学科。

框架试验位于瑞典农业科学大学于尔特乌纳（Ultuna）校区，自1956年起持续开展至今。该试验的研究目标为探究不同有机质与氮肥配施方案对土壤有机质含量、作物产量水平以及作物养分含量的影响。本数据集包含1956年至2023年间的作物、土壤与有机质养分含量以及作物产量数据。该数据集以单个TSV文件（RAM56_data.tsv）的形式提供，另有7个TSV文件用于补充背景信息。自试验启动以来科研人员采集的物理观测数据，以及试验期间部分时间点采集的植物与土壤样本，均存储于瑞典农业科学大学。