Occurrence cubes for non-native taxa in Belgium and Europe

<strong>Description</strong> This package contains aggregated occurrence data ("occurrence cubes") for non-native taxa in Belgium and Europe. These occurrence cubes were generated by grouping species occurrence data from the Global Biodiversity Information Facility (GBIF) by year (<code>year</code>), 1x1km spatial EEA reference grid cell (<code>eea_cell_code</code>) and taxon (<code>taxonKey</code> or <code>classKey</code>). For each grouping, the number of occurrences found in GBIF (<code>n</code>) and the minimum coordinateUncertaintyInMeters (<code>min_coord_uncertainty</code>) are provided. The provided coordinateUncertaintyInMeters of an occurrence is taken into account when assigning it to a grid cell (see this code). The occurrence cubes are used as input data for indicators and risk modelling/mapping for the Tracking Invasive Alien Species (TrIAS) project. The occurrence cubes are built on open science principles and intended to be completely reproducible: The input data are publicly available on GBIF, with the download DOIs listed in the related identifiers of this package. The code to process the data to cubes is publicly available on GitHub at https://github.com/trias-project/occ-cube-alien (version 20191030). <strong>Files</strong> <strong>be_alientaxa_cube.tsv</strong>: occurrence cube of alien taxa listed by the Global Register of Introduced and Invasive Species - Belgium (Desmet et al. 2019) and limited to occurrences in Belgium (<code>country=BE</code>). <strong>be_alientaxa_info.tsv</strong>: taxonomic information for taxa in <code>be_alientaxa_cube.tsv</code>. <strong>be_classes_cube.tsv</strong>: occurrence cube of all classes found in Belgium (<code>country=BE</code>), used to assess sampling effort bias in <code>be_alientaxa_cube.tsv</code>. <strong>eu_modellingtaxa_cube.tsv</strong>: occurrence cube of selected modelling species in Europe (bounding box). <strong>eu_modellingtaxa_info.tsv</strong>: taxonomic information for taxa in <code>eu_modellingtaxa_cube.tsv</code>.<strong>数据集描述</strong> 本数据集包收录比利时与欧洲范围内外来类群（non-native taxa）的聚合式物种出现数据，即<strong>出现数据立方体（occurrence cubes）</strong>。此类出现数据立方体通过对全球生物多样性信息设施（Global Biodiversity Information Facility, GBIF）的物种出现数据进行分组聚合生成，分组依据包括年份（<code>year</code>）、1×1千米空间欧洲环境署（European Environment Agency, EEA）参考格网单元（<code>eea_cell_code</code>）以及类群（<code>taxonKey</code>或<code>classKey</code>）。针对每一组数据，将提供在GBIF中检索到的出现记录数（<code>n</code>）与最小坐标不确定性值（<code>min_coord_uncertainty</code>）。在将出现记录分配至对应格网单元时，将纳入该记录提供的坐标不确定性值（详见配套代码）。此类出现数据立方体可作为《追踪外来入侵物种（Tracking Invasive Alien Species, TrIAS）》项目的指标构建与风险建模/制图工作的输入数据。本出现数据立方体遵循开放科学原则，旨在实现完全可复现：输入数据可于GBIF公开获取，其下载DOI已列于本数据集包的关联标识符中；将原始数据处理为数据立方体的代码已在GitHub开源，仓库地址为https://github.com/trias-project/occ-cube-alien（版本号20191030）。 <strong>数据集文件</strong> <strong>be_alientaxa_cube.tsv</strong>：收录全球引入与入侵物种登记册-比利时版（Global Register of Introduced and Invasive Species - Belgium，Desmet等2019年发布）中所列外来类群的出现数据立方体，且数据限定为比利时境内的出现记录（<code>country=BE</code>）。 <strong>be_alientaxa_info.tsv</strong>：<code>be_alientaxa_cube.tsv</code>中所涉类群的分类学信息。 <strong>be_classes_cube.tsv</strong>：收录比利时境内所有类群的出现数据立方体（<code>country=BE</code>），用于评估<code>be_alientaxa_cube.tsv</code>中的采样强度偏差。 <strong>eu_modellingtaxa_cube.tsv</strong>：欧洲范围内经筛选的建模用物种出现数据立方体（限定于研究边界框（bounding box）范围）。 <strong>eu_modellingtaxa_info.tsv</strong>：<code>eu_modellingtaxa_cube.tsv</code>中所涉类群的分类学信息。