National Forest Inventory England 2022

The National Forest Inventory (NFI) woodland map covers all forest and woodland area over 0.5 hectare with a minimum of 20% canopy cover, or the potential to achieve it, and a minimum width of 20 metres. This includes areas of new planting, clearfell, windblow and restock. The woodland map excludes all 'tarmac' roads and active railways, and forest roads, rivers and powerlines where the gap in the woodland is greater than 20 meters wide. All woodland (both urban and rural), regardless of ownership, is 0.5 hectare or greater in extent, with the exception of Assumed woodland or Low density areas that can be 0.1 hectare or greater in extent. Also, in the case of woodland areas that cross the countries borders, the minimum size restriction does not apply if the overall area complies with the minimum size. Woodland less than 0.5 hectare in extent, with the expectation of the areas above, will not be described within the dataset but will be included in a separate sample survey of small woodland and tree features. The woodland map is updated on an annual basis and the changes in the woodland boundaries use the Ordnance Survey MasterMap® (OSMM) as a reference where appropriated. The changes in the canopy cover have been identified on: Sentinel 2 imagery taken during spring/summer 2022 or colour aerial orthophotographic imagery available at the time of the assessment; New planting information for the financial year 2021/2022, from grant schemes and the sub-compartment database covering the estate of Forestry England, Forestry and Land Scotland and Natural Resources Wales; Woodland areas, greater than 0.5 hectares, are classified as an interpreted forest type (IFT) from aerial photography and satellite imagery. Non-woodland areas, open areas greater than 0.5 hectare completely surrounded by woodland are described according to open area types. IFT categories are Conifer, Broadleaved, Mixed mainly conifer, Mixed mainly broadleaved, Coppice, Coppice with standards, Shrub, Young trees, Felled, Ground prep, Cloud \ shadow, Uncertain, Low density, Assumed woodland, Failed, Windblow. IOA categories are Open water, Grassland, Agricultural land, Urban, Road, River, Powerline, Quarry, Bare area, Windfarm, Other vegetation. For further information regarding the interpreted forest types (IFT) and the interpreted open areas (IOA) please see NFI description of attributes available on www.forestresearch.gov.uk国家森林清查（National Forest Inventory, NFI）林地地图覆盖所有面积不小于0.5公顷、郁闭度至少20%或具备达到该郁闭度潜力，且最小宽度不低于20米的森林与林地。该范围包含新造林、皆伐迹地、风倒区及补植区域。本林地地图不包含所有柏油路面道路、运营中的铁路，以及林地间隙宽度超过20米的林道、河流与电力线路。所有林地（包括城市与乡村林地），无论权属如何，面积均需达到0.5公顷及以上，但假定林地或低密度区域的面积门槛可放宽至0.1公顷及以上。此外，若跨国家边界的林地整体面积符合最小面积要求，则不受单块面积限制。除上述区域外，面积小于0.5公顷的林地不会纳入本数据集，但会纳入小型林地与树木特征的独立抽样调查。林地地图每年更新一次，林地边界的变更以英国地形测量局主地图（Ordnance Survey MasterMap®, OSMM）为参考基准（适当时）。冠层覆盖度的变更通过以下方式识别：2022年春夏拍摄的哨兵2号（Sentinel 2）影像、评估时可用的彩色航空正射影像；2021/2022财年来自补助计划的新造林信息，以及覆盖英格兰林业局、苏格兰林业与土地局及威尔士自然资源局管辖辖区的小班数据库。面积大于0.5公顷的林地会通过航空摄影与卫星影像解译为林分类型（Interpreted Forest Type, IFT）。完全被林地环绕、面积大于0.5公顷的非林地开放区域，将按照开放地类进行分类。林分类型（IFT）类别包括针叶林、阔叶林、以针叶为主的混交林、以阔叶为主的混交林、矮林、带高木的矮林、灌丛、幼林、采伐迹地、整地、云/阴影、不确定、低密度林地、假定林地、失败造林、风倒区。解译开放区域（Interpreted Open Areas, IOA）类别包括开阔水域、草地、农用地、城镇用地、道路、河流、电力线路、采石场、裸地、风电场、其他植被。如需了解解译林分类型（IFT）与解译开放区域（IOA）的更多详细信息，请访问www.forestresearch.gov.uk 查阅国家森林清查的属性说明文档。