DOI: 10.5061/dryad.vx0k6dk08
title: Competitive interactions modify the direct effects of climate

description: As the climate is changing, species respond by changing distributions and
 abundances. The effects of climate are not only direct, but also occur via
 changes in biotic interactions, such as competition. Yet, the role of
 competition in mediating the effects of climate is still largely unclear.
 To examine how climate influences species performance, directly and via
 competition with other species, we transplanted two moss species differing
 in climate niches, alone and together at 59 sites along a climate
 gradient. Growth was monitored over three growing seasons. In the absence
 of competition, both species performed better under warmer conditions.
 When transplanted together, a warmer climate had instead negative effects
 on the northern moss, while the effects remained positive for the southern
 species. The negative effect of a cold climate for the southern species
 was larger when both species were transplanted together. Over three
 growing seasons, the southern species almost outcompeted the northern in
  warmer climates. Our results illustrate how competitive
 interactions can modify, and even reverse, the direct effects of climate
 on organism performance. A broader implication of our results is that
 species interactions can have important effects on how environmental and
 climate change influence performance and abundance.
description: # **Competitive interactions modify the direct effects of climate**
 [https://doi.org/10.5061/dryad.vx0k6dk08](https://doi.org/10.5061/dryad.vx0k6dk08) Data consists of three datasets and two scripts to reproduce models and figures for the manuscript "Competitive interactions modify the direct effects of climate" in review in Ecography. All NA values are replaced with the value 9999 to avoid any empty cells. NA (9999) values means that the value is not available. Scaled values are in the unit of standard deviations away from the mean 0. --- The csv file **mossdata** includes growth of single and mixed transplants of the two moss species and predictors. Columns are: **site:** site ID for transplant sites **moss_id:** ID for each moss transplant **moss:** moss species - S for Sanionia uncinata, and H for Hypnym cupressiforme **treatment:** Treatment is information combining origin of moss population and whether it is a single transplant or a mixed. \- HS is Hypnum cupressiforme from its southern population \- HN is Hypnum cupressiforme from its northern population. \- SS is Sanionia uncinate from its southern population. \- SN is Sanioina uncinata from its northern population \- HSSN is Hypnum cupressiforme from its southern population growing with Sanionia uncinata from its northern population. \- HNSN is Hypnum cupressiforme from its northern population growing with Sanionia uncinata from its northern population. \- HSSS is Hypnum cupressiforme from its southern population growing with Sanionia uncinata from its southern population. \- HNSS is Hypnum cupressiforme from its northern population growing with Sanionia uncinata from its southern population. **season:** Season of measure of moss transplants. **area:** Area of moss transplants in cm2. **lastseason:** Last season's area of moss transplants in cm2. **species2:** Moss species, S for Sanionia uncinata and H for Hypnum cupressiforme. **comp:** Competition, NO for single transplants, YES for mixed transplants. **range2:** Origin of moss - S for south, N for north, in the moss species respective range. **year2:** Year of measure of area of moss transplants. **GDD:** Growing Degree Days (climate variable from local measuring temperature loggers, unitless). **light_untransformed:** Light in terms of canopy openness (proportion). **light:** scaled light **VPD:** Vapor Pressure Deficit measure from local measuring temperature and humidity loggers (unit: kPa). **VPDscale:** VPD scaled **GDDscale:** GDD scaled **lastseason2:** scaled last season area of moss transplant. --- **predictors_60.csv** includes all predictors for all initial sites scaled and unscaled format for each year separately. Untransformed means not scaled. **site:** ID for transplant site **GDD:** Growing Degree Days (unitless) **VPD:** Vapor Pressure Deficit (unit kPa) **light:** Canopy openness (proportion). --- **propchangedat.csv** includes change in proportion of total area in cm2 held by the northern moss over three growing seasons with predictors. **site:** ID for transplant site **moss_id:** ID for moss transplant **range_S:** origin of Sanionia uncinata **comprange_S:** origin of Hypnum cupressiforme **propchange:** Proportional change in relative abundance between Sanionia uncinata and Hypnu cupressiforme in mixed transplants between the start of the transplant experiment in 2019 to the end in 2021. **GDDmean:** Mean values of GDD from 2019-2021 (unitless) **VPDmean:** Mean values of VPD from 2019-2021 (unit kPa). **light_untransformed:** Light, in terms of canopy openness (proportion). --- **Analysis_figure2_3.Rmd** script includes code to generate models and figure 2 and figure 3. **mossmap.Rmd** script includes code to generate the calculations of mean annual temperature for the European distribution of the two moss species as well as a occurrence map in 0.5 degrees resolution.