內容註: |
Introduction -- History of Soil Studies -- Soil-Forming Factor -- Elevation Gradients in the Oregon Mountain Ranges -- General Soil Regions of Oregon -- Diagnostic Horizons and Taxonomic Structure of Oregon Soils -- Taxonomic Soil Regions -- Mollisols -- Inceptisols -- Aridisols -- Andisols -- Ultisols -- Alfisols -- Entisols, Vertisols, Spodosols, and Histosols -- Soil-Forming Processes -- Benchmark, Endemic, Rare, and Endangered Soils -- Land Use in Oregon -- Yields, Soil Conservation, and Production System -- Summary. |