Delaware River Watershed Initiative - Soils 2015

Two seamless soils datasets based on USDA’s SSURGO and STATSGO databases were created for the entire DRB region, and information pertaining to various soil-related factors such as erodibility (k factor), available water - holding capacity, texture, etc. were compiled and summarized for discrete mapping units at these two scales. The SSURGO (Soil Survey Geographic) database is compiled at the detailed county-level survey scale that most soil information users are familiar with, and has two basic components: 1) digital boundaries of the detailed soil mapping units, and 2) tabular information on a wide range of soil parameters associated with each mapping unit. The STATSGO (State Soil Geographic) database summarizes similar soils information at a much more generalized “soil association” scale. Both of these datasets for the DRB area were downloaded from USDA’s “geospatial data” site at http://datagateway.nrcs.usda.gov. Once downloaded, considerable effort was then expended to first
seam together the data from the separate states overlapping the DRB, and then to “populate” both soil databases by linking a number of “attribute tables” to the soils polygons contained within the DRB boundary. In this case, over 325,000 soil polygons were populated with information extracted from about a dozen different attribute tables.

This data is hosted at, and may be downloaded or accessed from PASDA, the Pennsylvania Spatial Data Access Geospatial Data Clearinghouse http://www.pasda.psu.edu/uci/DataSummary.aspx?dataset=1506

基于美国农业部（USDA）的SSURGO和STATSGO数据库，针对整个DRB区域，创建了两个无缝的土壤数据集。这些数据集综合并概括了与土壤相关因素的信息，如可侵蚀性（k因子）、有效持水能力、质地等，针对不同尺度的离散地图单元进行了编制。SSURGO（土壤调查地理数据库）以详尽的县级行政区域为基准，是大多数土壤信息使用者所熟知的尺度，包含两个基本组成部分：1）详尽土壤图斑的数字化边界，2）与每个图斑相关的广泛土壤参数的表格信息。STATSGO（州土壤地理数据库）在更为通用的“土壤关联”尺度上对类似的土壤信息进行了总结。这两个DRB区域的数据集均从USDA的“地理空间数据”网站http://datagateway.nrcs.usda.gov下载而来。下载后，首先耗费大量精力将重叠于DRB的各个州的数据进行整合，然后通过将众多“属性表”链接到DRB边界内的土壤多边形中，对两个土壤数据库进行了“填充”。在此案例中，超过325,000个土壤多边形被填充了从约十个不同的属性表中提取的信息。该数据存储于PASDA（宾夕法尼亚空间数据访问地理空间数据中心）并可通过http://www.pasda.psu.edu/uci/DataSummary.aspx?dataset=1506下载或访问。