Land Use and Cropping Recommendations For Various Soil Types in Iowa, 1937-1938.

This dataset was transcribed and analyzed to support the article:Obrycki, J. F., and D. L. Karlen. 2018. “Optimizing Iowa Land Use: Past Perspectives for Current Questions.” <i>Journal of Soil and Water Conservation</i> 73 (6): 693–704. https://doi.org/10.2489/jswc.73.6.693<br>The dataset contains transcribed tables from the county pamphlets “How To Use Your Soil And Keep It Too” distributed by county agricultural planning committees in 1937/1938. There are 90 pamphlets available. One table was included in each pamphlet and was titled “Land Use and Cropping Recommendations For Various Soil Types.” The table included recommended crop rotations by soil type in the county. These tables were created by county agricultural planning committees. The values in the tables were committee recommendations for the types of crop rotations that would protect soils and provide suitable crop production. The dataset contains additional columns that evaluated the county agricultural planning committee recommendations. Two supporting datasets are provided to explain the column assignments using in the primary dataset.<br>

本数据集经转录与分析，用于支撑下述研究论文：奥布里基（J. F. Obrycki）与卡伦（D. L. Karlen）于2018年发表的《优化爱荷华州土地利用：解答当前问题的历史视角》，刊载于《土壤与水保护学报（Journal of Soil and Water Conservation）》第73卷第6期，页码693–704，DOI：10.2489/jswc.73.6.693。
本数据集包含1937至1938年间由各县级农业规划委员会发行的县级手册《如何合理利用土壤并维持地力（How To Use Your Soil And Keep It Too）》中的转录表格。目前共留存90份该类手册，每份手册均包含一张题为“不同土壤类型的土地利用与种植建议（Land Use and Cropping Recommendations For Various Soil Types）”的表格，内容为该县针对不同土壤类型制定的推荐作物轮作方案。该类表格由县级农业规划委员会编制，表格内的数值为委员会提出的、既能保护土壤又能实现合理作物生产的轮作方案建议。本数据集还增设了额外列项，用于评估上述县级农业规划委员会的推荐方案。
此外，本数据集附带两份辅助数据集，用以说明主数据集中各列的赋值规则。