Soil Colors CONUS 50 cm 2022
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The soil_colors_conus services show the aggregated soil color for each state at specific depths. The soil colors represented here express over 100 years of soil survey work carried out as part of the National Cooperative Soil Survey. The 30 meter soil color data layers express the native resolution of the data sources from which they were compiled. The soil color maps were created using a combination of spatial and tabular data sources and representing 8 depth slices. Moist soil colors were derived from a snapshot of the Official Series Descriptions (OSDs), and a snapshot of pedons linked to SSURGO components (component pedons, not a public data source). The spatial arrangement of soil color is based on the FY22 gNATSGO map unit key grid (30m). Linkages between gNATSGO grid cell and tabular data are based on explicit links between component records and component pedons when available, or matching component name to a soil series name. Within map units, the most frequent soil color (for each depth slice) was determined via component percentage. Soil colors maps were developed at 8 depth slices (5cm, 10cm, 15cm, 25cm, 50cm, 75cm, 100cm, 125cm) when possible, with a place-holder ROCK color (N 8/0) used in slices below contact with bedrock. The ROCK color was also used for map units containing mostly rock outcrop, rubble land, river wash, urban land, pits, dumps, and badlands. Special colors were also assigned to map units containing mostly water features (5PB 1/22) and playas (5Y 8/2). The most frequent (moist) soil color was assigned to each MLRA polygon, according to the most extensively mapped soil series within each MLRA. These colors were used as a backup when no other color could be assigned to a gNATSGO grid cell. For each depth slice, a moist soil color was assigned to each gNATSGO grid cell according to the following logic: 1. if present, use soil color from the RV component pedon, otherwise 2. attempt to use soil color from matching OSD, otherwise 3. use ROCK color if the given slice is below contact with bedrock, otherwise 4. use one of the place-holder colors for misc. area components such as WATER, ROCK, or PLAYAS, otherwise 5. fill with the most-likely soil color by MLRA. Soil colors were qualitatively evaluated by visually comparing soil color to landform positions such as drainageways normally having darker colors due to increased available moisture and more vigorous vegetation production. The finest horizontal resolution used to generate soil colors is 30 meters, therefore any soil delineation or class smaller than this threshod is lost to a neighbor. This would typically occur at the boundaries of a soil survey area. Unique lookup value relating to Munsell color notations converted to RGB values using the aqp package in R. This data set is not designed for use as a primary regulatory tool in permitting or citing decisions, but may be used as a reference source. Purpose: To provide soil colors conus imagery. Creation Date: 2022 Publication Date: 20230317 Revision Date: Refresh Cycle: Periodically as new soil color data becomes available Version: 1.0.0
soil_colors_conus 服务展示了美国本土各州在特定深度下的聚合土壤颜色。本数据集呈现的土壤颜色成果，源自跨越百余年的国家合作土壤调查（National Cooperative Soil Survey）工作。该30米分辨率的土壤颜色数据图层，完整保留了其原始数据源的空间分辨率。 本土壤颜色地图整合了空间与表格两类数据源，共涵盖8个深度切片。湿润土壤颜色数据源自官方土系描述（Official Series Descriptions, OSDs）的快照，以及与SSURGO土壤调查地理数据库（SSURGO）要素关联的土壤单体快照（仅要素关联土壤单体，非公开数据源）。土壤颜色的空间分布基于2022财年（FY22）版gNATSGO通用国家土壤地理数据库（gNATSGO）图斑密钥网格（30米分辨率）。 gNATSGO网格单元与表格数据的关联规则为：优先采用要素记录与对应土壤单体的显式关联（若可用），否则通过要素名称匹配土系名称实现关联。在单个图斑内，通过要素占比确定各深度切片下出现频率最高的土壤颜色。 本数据集尽可能生成了8个深度切片（5cm、10cm、15cm、25cm、50cm、75cm、100cm、125cm）的土壤颜色地图，当采样深度超过基岩接触面时，使用占位符岩石颜色（N 8/0）填充。该岩石颜色同样适用于以岩石露头、碎石地、河道冲刷区、城市用地、坑洼、堆弃地以及劣地为主的图斑。此外，还为以水体为主的图斑（5PB 1/22）和干盐湖（5Y 8/2）分配了专用占位颜色。 针对每个主要土地资源区（Major Land Resource Areas, MLRA）多边形，根据区内分布最广泛的土系，确定其对应的最常见湿润土壤颜色，该颜色可作为无法为gNATSGO网格单元分配颜色时的备用方案。 各深度切片下的gNATSGO网格单元湿润土壤颜色分配遵循以下逻辑：1. 若存在RV要素关联土壤单体，则直接采用其土壤颜色；2. 否则尝试通过匹配的OSD获取土壤颜色；3. 若当前深度超过基岩接触面，则使用岩石颜色；4. 若为水体、岩石或干盐湖等杂类区域要素，则使用对应占位颜色；5. 最后根据所属MLRA填充最可能的土壤颜色。 研究人员通过视觉对比的方式对土壤颜色进行了定性评估，例如将颜色与地形位置关联：汇水区通常因水分有效性更高、植被生长更旺盛而颜色更深。本数据集生成所采用的最高水平空间分辨率为30米，因此任何小于该阈值的土壤描绘图斑或分类单元将被相邻单元合并，这种情况通常出现在土壤调查区域的边界处。 本数据集采用R语言的aqp数据包（aqp package in R），将孟塞尔颜色标注（Munsell color notations）转换为RGB值后生成唯一查找值。本数据集并非用于作为许可审批或决策引用的主要监管工具，但可作为参考数据源使用。 用途：提供美国本土土壤颜色影像。 创建日期：2022年 发布日期：20230317 修订日期： 更新周期：定期随新土壤颜色数据的发布进行更新 版本：1.0.0
