Utah Water Related Land Use

Feature Classes are loaded onto tablet PCs and Field crews are sent to label the crop or land cover type and irrigation method for a subset of select fields or polygons. Each tablet PC is attached to a GPS unit for real-time tracking to continuously update the field crew’s location during the field labeling process. Digitizing is done as Geodatabase feature classes using ArcPro 3.1.0 with Sentinel imagery as a background with other layers added for reference. Updates to existing field boundaries of individual agricultural fields, urban areas and more are precisely digitized. Changes in irrigation type and land use are noted during this process. Cropland Data Layer (CDL) rasters from the United States Department of Agriculture (USDA) National Agricultural Statistics Service (NASS) are downloaded for the appropriate year. https://nassgeodata.gmu.edu/CropScape/ Zonal Statistics geoprocessing tools are used to attribute the polygons with updated crop types from the CDL. The data is then run through several stages of comparison to historical inventories and quality checking in order to determine and produce the final attributes. LUID - Unique ID number for each polygon in the final dataset, not consistent between yearly datasets. Landuse - A general land cover classification differentiating how the land is used. Agriculture: Land managed for crop or livestock purposes. Other: A broad classification of wildland. Riparian/Wetland: Wildland influenced by a high water table, often close to surface water. Urban: Developed areas, includes urban greenspace such as parks. Water: Surface water such as wet flats, streams, and lakes. CropGroup - Groupings of broader crop categories to allow easy access to or query of all orchard or grain types etc. Description - Attribute that describes/indicates the various crop types and land use types determined by the GIS process. IRR_Method - Crop Irrigation Method carried over from statewide field surveys ending in 2015 and updated based on imagery and yearly field checks. Drip: Water is applied through lines that slowly release water onto the surface or subsurface of the crop. Dry Crop: No irrigation method is applied to this agricultural land, the crop is irrigated via natural processes. Flood: Water is diverted from ditches or pipes upland from the crop in sufficient quantities to flood the irrigated plot. None: Associated with non-agricultural landSprinkler: Water is applied above the crop via sprinklers that generally move across the field. Sub-irrigated: This land does not have irrigation water applied, but due to a high water table receives more water, and is generally closely associated with a riparian area. Acres - Calculated acreage of the polygon. State - State where the polygons are found. Basin - The hydrologic basin where the polygons are found, closely related to HUC 6. These basin boundaries were created by DWRe to include portions of other basins that have inter-basin flows for management purposes. SubArea - The subarea where the polygons are found, closely related to the HUC 8. Subareas are subdivisions of the larger hydrologic basins created by DWRe. Label_Class - Combination of Label and Class_Name fields created during processing that indicates the specific crop, irrigation, and whether the CDL classified the land as a similar crop or an “Other” crop. LABEL - A shorthand descriptive label for each crop description and irrigation type. Class_Name - The majority pixel value from the USDA CDL Cropscape raster layer within the polygon, may differ from final crop determination (Description). OldLanduse - Similar to Landuse, but splits the agricultural land further depending on irrigation. Pre-2017 datasets defined this as Landuse. LU_Group - These codes represent some in-house groupings that are useful for symbology and other summarizing. Field_Check - Indicates the year the polygon was last field checked. *New for 2019 SURV_YEAR - Indicates which year/growing season the data represents.要素类（Feature Classes）被加载至平板电脑，外业人员被派遣至选定的部分田块或多边形区域，标注作物类型、土地覆被类型与灌溉方式。每台平板电脑均搭载GPS单元，实现实时定位追踪，在外业标注过程中持续更新外业人员的位置信息。 数字化工作采用ArcPro 3.1.0制作地理数据库（Geodatabase）要素类，以哨兵（Sentinel）影像作为底图，并叠加其他参考图层。研究人员对单个农田、城市区域等现有田块边界进行精准数字化更新，同时记录灌溉类型与土地利用方式的变更情况。 从美国农业部（United States Department of Agriculture, USDA）国家农业统计服务局（National Agricultural Statistics Service, NASS）下载对应年份的作物数据图层（Cropland Data Layer, CDL）栅格数据，数据来源网址为https://nassgeodata.gmu.edu/CropScape/。 使用分区统计（Zonal Statistics）地理处理工具，为多边形赋予来自CDL的更新后作物类型属性。随后，数据集将经过多轮与历史清单的对比及质量检查流程，以确定并生成最终属性信息。 LUID：最终数据集中每个多边形的唯一标识符，不同年份的数据集之间该ID不具有一致性。 Landuse（土地利用类型）：通用土地覆被分类体系，用于区分土地利用方式。其中，农业用地（Agriculture）：用于作物种植或畜牧管理的土地；其他用地（Other）：广义的野生用地范畴；河岸/湿地（Riparian/Wetland）：受高地下水位影响的野生用地，通常紧邻地表水体；城市用地（Urban）：已开发区域，包含公园等城市绿地；水体（Water）：地表水体，如湿滩、溪流与湖泊。 CropGroup（作物组）：更宽泛的作物类别分组，便于快速检索所有果园、谷物类作物等类型。 Description（描述信息）：通过GIS流程确定的各类作物类型与土地利用类型的属性说明字段。 IRR_Method（灌溉方式）：继承自2015年结束的全州外业调查成果，并基于影像与年度外业核查进行更新。各灌溉方式说明如下：滴灌（Drip）：通过管道缓慢向作物表层或地下层供水；旱地作物（Dry Crop）：该农田未施加人工灌溉，作物依靠自然过程获取水分；漫灌（Flood）：从作物上游的沟渠或管道引水，以足够水量淹没灌溉地块；无灌溉（None）：对应非农业用地；喷灌（Sprinkler）：通过可在田间移动的喷头向作物上方喷水；地下水位补给灌溉（Sub-irrigated）：该地块未人工施加灌溉水，但因高地下水位获得充足水分，通常与河岸区域密切相关。 Acres（地块面积）：多边形区域的计算所得英亩数。 State（所属州）：多边形区域所在的州。 Basin（水文流域）：多边形区域所在的水文流域，与HUC 6密切相关。该流域边界由DWRe划定，为便于管理纳入了存在跨流域水流的其他流域部分区域。 SubArea（次级流域分区）：多边形区域所在的次级流域分区，与HUC 8密切相关。次级流域分区是DWRe划定的大型水文流域的下级子单元。 Label_Class（标签类别）：处理过程中生成的Label与Class_Name字段的组合，用于说明具体作物类型、灌溉方式，以及CDL是否将该地块归类为相似作物或"Other"作物。 LABEL（标签简称）：各类作物描述与灌溉类型的简短描述性标签。 Class_Name（类别名称）：多边形区域内USDA CDL作物景观（Cropscape）栅格图层中的多数像元值，可能与最终确定的作物类型（Description字段）存在差异。 OldLanduse（旧土地利用类型）：与Landuse类似，但根据灌溉方式对农业用地进行了更细致的划分。2017年之前的数据集将该字段定义为Landuse。 LU_Group（土地利用分组代码）：该代码代表部分内部分组，可用于符号化展示及其他汇总统计工作。 Field_Check（外业核查年份）：标注该多边形最近一次接受外业核查的年份。*2019年新增字段 SURV_YEAR（调查年份）：说明数据集所代表的年份或生长季。