World Soils Harmonized World Soil Database - General

Retirement Notice: This item is in mature support as of April 2024 and will be retired in December 2026. A new version of this item is available for your use. Esri recommends updating your maps and apps to use the new version. Soil is a key natural resource that provides the foundation of basic ecosystem services. Soil determines the types of farms and forests that can grow on a landscape. Soil filters water. Soil helps regulate the Earth's climate by storing large amounts of carbon. Activities that degrade soils reduce the value of the ecosystem services that soil provides. For example, since 1850 35% of human caused green house gas emissions are linked to land use change. The Soil Science Society of America is a good source of additional information. Dataset Summary This layer provides access to a 30 arc-second (roughly 1 km) cell-sized raster with attributes describing the basic properties of soil derived from the Harmonized World Soil Database v 1.2. The values in this layer are for the dominant soil in each mapping unit (sequence field = 1). Attributes in this layer include: Soil Phase 1 and Soil Phase 2 - Phases identify characteristics of soils important for land use or management. Soils may have up to 2 phases with phase 1 being more important than phase 2. Other Properties - provides additional information important for agriculture. Additionally, 3 class description fields were added by Esri based on the document Harmonized World Soil Database Version 1.2 for use in web map pop-ups: Soil Phase 1 Description Soil Phase 2 Description Other Properties Description The layer is symbolized with the Soil Unit Name field. The document Harmonized World Soil Database Version 1.2 provides more detail on the soil properties attributes contained in this layer. Other attributes contained in this layer include: Soil Mapping Unit Name - the name of the spatially dominant major soil group Soil Mapping Unit Symbol - a two letter code for labeling the spatially dominant major soil group in thematic maps Data Source - the HWSD is an aggregation of datasets. The data sources are the European Soil Database (ESDB), the 1:1 million soil map of China (CHINA), the Soil and Terrain Database Program (SOTWIS), and the Digital Soil Map of the World (DSMW). Percentage of Mapping Unit covered by dominant component

停用通知：本项目自2024年4月起进入成熟支持阶段，并将于2026年12月正式停用。当前已有该项目的新版本可供使用，Esri建议您尽快更新地图与应用程序，以适配新版本。

土壤是关键的自然资源，为基础生态系统服务提供核心支撑。土壤决定了区域内可发展的农业与林业类型，能够过滤水体，并通过储存大量碳元素助力调节地球气候。土壤退化活动会削弱其提供的生态系统服务价值。例如，自1850年以来，35%的人为温室气体排放与土地利用变化相关。美国土壤科学学会（Soil Science Society of America）是获取更多相关信息的优质渠道。

数据集摘要
本图层可访问分辨率为30弧秒（约1公里）的栅格数据，其栅格单元属性源自《统一世界土壤数据库v1.2》（Harmonized World Soil Database v1.2，以下简称HWSD），描述了土壤的基本特性。本图层的取值对应每个制图单元中的优势土壤（序列字段=1）。图层包含的属性如下：
1. 土壤相1与土壤相2：相型用于标识土地利用或管理中关键的土壤特征，单一场景的土壤最多可包含2个相型，其中土壤相1的重要性高于土壤相2。
2. 其他属性：提供与农业生产密切相关的补充信息。

此外，Esri基于《Harmonized World Soil Database Version 1.2》文档新增了3个分类描述字段，用于网页地图弹窗展示：土壤相1描述、土壤相2描述、其他属性描述。

本图层以“土壤单元名称”字段进行符号化渲染。《Harmonized World Soil Database Version 1.2》文档对本图层包含的土壤属性字段有更详细的说明。

本图层包含的其他属性还有：
- 土壤制图单元名称：空间分布上占主导的主要土壤群名称
- 土壤制图单元符号：用于专题地图中标注优势主要土壤群的双字母代码
- 数据来源：HWSD为多数据集聚合产物，其数据源包括欧洲土壤数据库（European Soil Database, ESDB）、中国1:100万土壤图（CHINA）、土壤与地形数据库计划（Soil and Terrain Database Program, SOTWIS）以及世界数字土壤图（Digital Soil Map of the World, DSMW）
- 制图单元中优势组分的覆盖百分比