Alnus cordata chorology

Distribution map of Italian alder (<i>Alnus cordata</i>)<br><br>These maps were produced by combining numerous and heterogeneous data collected from atlas monographs providing complete species distribution maps, from national to regional atlases, occurrence geo-databases, scientific and grey literature.<br>The maps were created using ESRI shapefiles (*.shp, *.shx, *.dbf, *.prj files) archived in the ZIP file. Species range is mapped with polygon features (name suffix "plg"), which define continuous areas of occupancy of the species, and with point features (name suffix "pnt"), which identify more fragmented and isolated populations. If synanthropic occurrences are reported outside the species natural range, additional point and/or polygon shapefiles are also present (suffix "syn"). <br>Polygon borders delimiting species ranges are generalized across the mainland and sea boundaries. This offers the possibility to mask sea areas or to clip and extract the terrestrial range parts using GIS data layers of the users' choice. An additional version of polygon ranges are clipped with a coastline (name suffix "clip"), which have been derived from Natural Earth dataset "Admin 0 - Countries" 1:50M version 4.1.0 (https://www.naturalearthdata.com). <br><br>Please cite as:<br>Caudullo, G., Welk, E., San-Miguel-Ayanz, J., 2017. Chorological maps for the main European woody species. Data in Brief 12, 662-666. DOI: doi.org/10.1016/j.dib.2017.05.007 <br><br>Additional information and used references are on 'supplementary materials' document:<br>https://doi.org/10.6084/m9.figshare.5091901<br><br>Chorological maps are part of the "European Atlas of Forest Tree Species" project:<br>https://w3id.org/mtv/FISE-Comm/v01

意大利桤木（Alnus cordata）分布图谱

本系列图谱通过整合多源异构数据编制而成，数据来源涵盖覆盖从国家级到区域级尺度的完整物种分布图谱的图集专著、物种出现点地理数据库，以及正式学术文献与灰色文献。

本图谱以ESRI形状文件（*.shp、*.shx、*.dbf、*.prj）格式打包存储于ZIP压缩包内。物种分布范围通过两类地理要素进行表征：其一为面要素（文件名后缀为"plg"），用于界定物种连续占据的栖息区域；其二为点要素（文件名后缀为"pnt"），用于标识更为破碎且孤立的种群分布点。若在物种自然分布范围之外存在人为伴生的出现记录，则将附带额外的点或面形状文件（后缀为"syn"）。

用于界定物种分布范围的面边界已针对陆地与海域边界进行了概化处理，使用者可借助自选的GIS数据图层遮蔽海域区域，或裁剪提取陆域分布范围部分。另有一类经过海岸线裁剪的面分布范围版本（文件名后缀为"clip"），其海岸线数据取自Natural Earth数据集"Admin 0 - Countries"1:50M版本4.1.0（https://www.naturalearthdata.com）。

请按以下格式引用：
Caudullo, G., Welk, E., San-Miguel-Ayanz, J., 2017. 欧洲主要木本物种分布区图谱. 数据简报（Data in Brief）12, 662-666. DOI: doi.org/10.1016/j.dib.2017.05.007

更多详细信息及参考文献可参阅《补充材料》文档：https://doi.org/10.6084/m9.figshare.5091901

本分布区图谱为"欧洲林木树种图集"（European Atlas of Forest Tree Species）项目的组成部分：https://w3id.org/mtv/FISE-Comm/v01