Land use, 2005, Ipswich Watershed, Parker Watershed, Plum Island Ecosystem, Massachusetts - vector

This is a statewide, seamless digital dataset of land use / land cover for the State of Massachusetts derived using semi-automated methods and based on digital imagery captured in 2005 with 0.5 m pixel resolution. The project area encompasses the State of Massachusetts. The minimum mapping unit (MMU) for this dataset is 1 acre overall for the dataset. However, there are some exceptions: a MMU of 0.5 acre has been used for rural areas where there may be isolated residential, commercial, or industrial structures. In such cases, areas less than 1 acre and more than about 0.5 acre are mapped. In urban areas, the MMU is 1 acre. This implies that a water tower or a communication tower in the middle of a residential or commercial area may not be mapped out separately if it occupies less than 1 acre of land. In areas where assessor parcel data was available, Multi-family Residential, Commercial, and Industrial areas may be as small as 0.25 acre. The land use classification scheme used for these data is based on a coding schema used in previous land use datasets in Massachusetts with some modifications for the 2005 classification. Note: Complete metadata is available within the downloaded zip file. This metadata can be viewed with ESRI ArcGIS software, and can be exported to FGDC and ISO metadata formats.

本数据集为马萨诸塞州全域无缝式土地利用/土地覆被数字化数据集，采用半自动化方法构建，基于2005年采集的0.5米像素分辨率数字影像生成。
本项目覆盖范围为马萨诸塞州全境。
本数据集整体最小制图单元（Minimum Mapping Unit, MMU）为1英亩，但存在部分例外：针对存在孤立住宅、商业或工业设施的乡村区域，采用0.5英亩作为最小制图单元，此时将对面积介于约0.5英亩至1英亩之间的区域进行制图。
在城市区域，最小制图单元仍为1英亩。这意味着若住宅或商业区中的水塔、通信塔占地面积不足1英亩，则不会单独将其作为独立地物进行制图。
在可获取评估地块数据的区域，多户住宅、商业及工业用地的最小制图单元可小至0.25英亩。
本数据集所采用的土地利用分类方案，基于马萨诸塞州既往土地利用数据集的编码体系，并针对2005年的分类需求进行了部分调整。
注：完整元数据可在下载得到的压缩包中获取，可通过ESRI ArcGIS软件查看，并可导出为FGDC及ISO元数据格式。