Soil health research has developed soil tests to validate management strategies for creating healthier soils, such as cover crops, compost, and reduced tillage. Missing in this research agenda are soil health management strategies and diagnostics tailored to the systematic variation of soils. The Soil Survey Geographic (SSURGO) database offers comprehensive estimates for many properties linked to soil health indicators. This research uses unsupervised classification of soil surface (0–30 cm) properties and root restrictive horizons in an internationally important agricultural region, the Central and Coastal Valleys of California, covering 5.6 million ha of mostly cropland. K‐means clustering of 10 soil properties derived from SSURGO revealed groups distinct from USDA‐NRCS Soil Taxonomy. Clustering metrics, data visualization, and validation tests justified a seven‐region soil health conceptual model that divided the landscape into two broad classes—those with and without performance limitations. Results revealed three pedogenic conditions limiting soil performance: (a) root restrictive horizons that impede root growth into deeper soil; (b) salinity and alkalinity harmful to crops; and (c) shrink–swell properties making soils challenging to cultivate. Soils without performance limitations, soils with restrictive horizons, and salt‐affected soils are further divided by texture and/or organic matter for a total of seven soil health regions. In reality, variation in soil properties is often continuous across the landscape and sometimes fractal in nature, but this research establishes a testable framework for evaluating soil health diagnostics according to geographically coherent differences in soil properties, demonstrating potential for how soil health management and interpretation can be tailor‐made to the landscape.

中文翻译：

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改善土壤健康诊断和管理的区域土壤分类框架

土壤健康研究已经开发了土壤测试，以验证创建更健康土壤的管理策略，例如覆盖作物，堆肥和减少耕种。该研究议程中缺少针对土壤系统变化量身定制的土壤健康管理策略和诊断方法。土壤调查地理（SSURGO）数据库提供了许多与土壤健康指标相关的属性的综合估计。这项研究使用了国际上重要的农业地区，加利福尼亚中部和沿海山谷，覆盖560万公顷大部分农田的土壤表面（0–30厘米）特性和根限制层的无监督分类。ķ对来自SSURGO的10种土壤特性的均值聚类揭示了与USDA-NRCS土壤分类法不同的群体。聚类指标，数据可视化和验证测试证明了一个由七个区域组成的土壤健康概念模型的合理性，该模型将地貌分为两大类-有和没有性能限制的类别。结果表明，有3个成岩条件限制了土壤的性能：（a）限制根系生长的根系，阻碍了根系生长到更深的土壤中；（b）对作物有害的盐碱度；（c）收缩膨胀特性使土壤难以耕种。对于总共七个土壤健康区域，没有性能限制的土壤，视野受限的土壤和受盐影响的土壤会进一步按质地和/或有机质划分。事实上，