Environmental drivers of plant distributions at global and regional scales: occurrence data with associated environmental variables of plant families/genera/species

How environmental factors drive plant distribution across globe is one of
the most fundamental questions in ecology. Plant
distributions may be shaped by various environmental factors,
such as climate, topography and edaphic factors. Nevertheless, it is not
clear about the relative importance of different environmental factors in
driving plant distribution across spatial scales and among plant groups.
This study aimed to disentangle how plant–environment
relationships vary with latitude and among plant taxa including
angiosperms, gymnosperms, pteridophytes and bryophytes. Location: Global
Main taxa: Plants Results: Our analyses revealed the primacy of climatic
variability (temperature seasonality and isothermality) on plant
distribution at the global scale. The relative contribution of
temperature
seasonality and isothermality peaked in
tropical areas, whereas solar radiation and annual mean temperature had
stronger influence at high-latitude areas. We also found
wide-range plant groups tend to occur at area with higher temperature
variability (isothermality and temperature
seasonality) and flatter terrain (low slope). Climate
extremes (low temperature and low solar radiation)
determined plant distribution range and limits across
latitude. Soil and topography had diverse thought less
important effects (related to climate) on broad-scale
plant distribution patterns. Main Conclusions: Our study
highlights the significance of climate variability for global
plant distributions and climate extremes at higher latitude areas.
Environmental effects of plant distributions vary across latitude. The
findings imply that our understandings on environmental factors
affecting plant distributions rely on the geographical scales
that we focus on, suggesting that different geographcial and local
ecological processes should be integrated to explain multi-scale
distribution patterns.