Niche properties constrain occupancy but not abundance patterns of native and alien woody species across Hawaiian forests

This data set accompanies the manuscript titled "Niche properties constrain occupancy but not abundance patterns of native and alien woody species across Hawaiian forests" published in Journal of Vegetation Science.<br><b>Objective</b>: We examine abundance-occupancy relationships of native and alien woody plant species, and the role of niche properties and functional traits related to dispersal and competition in shaping occupancy and abundance patterns.<br><b>Data</b>: The data file is compiled for 64 native and alien woody species that occur across the Hawaiian archipelago.<br><b>Description of data</b>: <br><br>Scientific_name: scientific name of each woody species<br>Native_Status: either native or alien<br>FirstRecord: Year alien species first recorded in Hawai'i. NAs for native species.<br>WD: wood density, in g cm^-3. Includes imputed values; please consult Table S1 to see which values are imputed. <br><br>SeedMass_mg: seed mass in mg. Includes imputed values; please consult Table S1 to see which values are imputed<br>Height_m: Maximum height in m. No values are imputed. <br><br>Niche_breadth: Estimated as n-dimensional hypervolume, based on climatic and topographic variables. Only estimated for 58 of the 64 species.<br><br>Niche_position: Estimated as absolute value of the centroid of the n-dimensional hypervolume from the first dimension. Only estimated for 58 of the 64 species.<br><br> Island: Indicates island for which abundance and occupancy were estimated. <br><br>meanRelAbund: Mean relative abundance for each species per island. Values estimated from forest plots. <br><br>medRelAbund: Median relative abundance for each species per island. Values estimated from forest plots. <br><br>Rel_Occupancy: Relative occupancy per species per island. Estimated as the percentage of 32 km2 grid cells in which a species is present.

本数据集配套于发表于《Journal of Vegetation Science》（植被科学期刊）的题为《Niche properties constrain occupancy but not abundance patterns of native and alien woody species across Hawaiian forests》的研究手稿。
<b>研究目标</b>：本研究旨在探究本土与外来木本植物的多度-占据率关系，以及生态位属性与扩散、竞争相关功能性状在塑造占据率与多度格局过程中的作用。
<b>数据集概况</b>：本数据集涵盖了分布于夏威夷群岛的64种本土与外来木本植物。
<b>数据字段说明</b>：

Scientific_name：木本植物的物种学名
Native_Status：物种起源类型，取值为本土（native）或外来（alien）
FirstRecord：外来物种在夏威夷群岛的首次记录年份，本土物种对应值为缺失值（NAs）
WD：木材密度，单位为克每立方厘米（g·cm⁻³），包含插补值；具体插补值信息请参见附表S1
SeedMass_mg：种子质量，单位为毫克（mg），包含插补值；具体插补值信息请参见附表S1
Height_m：植物最大株高，单位为米（m），无插补值
Niche_breadth：生态位宽度，基于气候与地形变量估算得到的n维超体积（n-dimensional hypervolume），仅对64个物种中的58个完成估算
Niche_position：生态位位置，以n维超体积第一维度的质心绝对值估算得到，仅对64个物种中的58个完成估算
Island：物种多度与占据率估算对应的岛屿
meanRelAbund：各物种在对应岛屿上的平均相对多度，数据来源于森林样地调查估算结果
medRelAbund：各物种在对应岛屿上的中位相对多度，数据来源于森林样地调查估算结果
Rel_Occupancy：各物种在对应岛屿上的相对占据率，以物种出现的32平方千米网格单元占比估算得到