DOI: 10.5061/dryad.7m0cfxq1t
title: Data from: Annual species’ experimental germination responses to light and temperature do not correspond with their microhabitat associations in the field

description: Annual species have evolved sets of germination cues that are thought to
 be predictive of the post-germination environment. In naturally patchy
 environments, germination microsites often vary considerably in the amount
 of light they receive and in the diurnal temperature fluctuations they
 experience. However, whether species’ differential germination responses
 to light and temperature are associated with their spatial patterns of
 occurrence remains largely untested. We surveyed species’ occurrences in
 annual plant communities in 150 quadrats across gradients of canopy cover
 and litter cover. Nineteen species recorded in this survey were then
 included in a germination experiment that manipulated (1) Light vs. Dark
 (12h light or continuous dark) approximating seeds near the soil surface
 versus those covered by litter and (2) Cold vs. Warm temperature regimes
 (7/18 °C and 7/24 °C) approximating diurnal fluctuations experienced in
 shaded versus sun-exposed microsites, respectively. In the germination
 experiment, six species had highest germination probabilities in the Light
 treatment (regardless of temperature), five in Cold + Light, one in Warm +
 Light, two were indifferent to the treatments, and four did not germinate
 at all. Binomial linear mixed-effects models showed that species’ maximum
 responses to light and temperature did not explain their spatial
 distributions along canopy cover and litter cover gradients, contrary to
 theoretical expectations of germination being a strong driver of species’
 occurrences. Despite variation in species’ responses to experimental
 treatments, no association was found with their field microsite
 associations. Germination strategies in our system were wider than
 expected for Mediterranean systems. Our results support that germination
 cues are not strong drivers of microhabitat associations in this system.
description: We surveyed species’ occurrences in annual plant communities in
 150 quadrats across gradients of canopy cover and litter cover. Nineteen
 species recorded in this survey were then included in a germination
 experiment that manipulated (1) Light vs. Dark (12h light or continuous
 dark) approximating seeds near the soil surface versus those covered by
 litter and (2) Cold vs. Warm temperature regimes (7/18 °C and 7/24 °C)
 approximating diurnal fluctuations experienced in shaded versus
 sun-exposed microsites, respectively. Analyses were
 performed in R.
description: # Annual species’ experimental germination responses to light and
 temperature do not correspond with their microhabitat associations in the
 field Date created 01/03/2024 Authors: Isis A. da Silva, School of the
 Environment, The University of Queensland, St Lucia, QLD, Australia David
 J. Merrit, Kings Park Science, Department of Biodiversity Conservation and
 Attractions, Kings Park, WA, 6005, Australia and School of Biological
 Sciences, The University of Western Australia, 35 Stirling Highway,
 Crawley, WA 6009, Australia Todd E. Erickson, Kings Park Science,
 Department of Biodiversity Conservation and Attractions, Kings Park, WA,
 6005, Australia and Centre for Engineering Innovation: Agriculture and
 Ecological Restoration, School of Agriculture and Environment, The
 University of Western Australia, 35 Stirling Highway, Crawley, WA 6009,
 Australia Margaret M. Mayfield, School of Biosciences, The University of
 Melbourne, Parkville, VIC, Australia John M. Dwyer, School of the
 Environment, The University of Queensland, St Lucia, QLD, Australia Below
 are the metadata for data files -&gt; Germination_Occurrence.html contain
 code summary and all outputs including tables and figures and can be used
 to understand the analyses without R; To run all analyses: (1) Download
 and unzip the "Germination_Occurrence_Project" folder from
 Zenodo; (2) Create a "Data" and a "Outputs" folder
 into "Germination_Occurrence_Project"; (3) Download the data
 files (".csv") and save inside the "Data" folder; (4)
 Open the "Germination_Occurrence_Project.Rproj" file and then
 run Germination_Occurrence.Rmd script Datasets associated with this
 analysis: "baseline.csv" Data for calculating mean germination
 percentage of fresh seeds species- taxon scientific name treatment -
 experimental conditions in which germination was monitored. Light is
 12h/12h dark/light and Dark is continuous darkness rep- Replicate or Petri
 dish day_41- day of the first monitoring day_56- day of the second
 monitoring "cumulative_curve.csv" Data for cumulative
 germination curve for the main experiment species- taxon scientific name
 temp- temperature treatment. Cold (7/18°C) or Warm (7/24°C) light- light
 treatment. Light is 12h/12h dark/light and Dark is continuous darkness
 total_seeds_dish- is the total seeds sown in each dish total_seeds- total
 number of seeds sown per treatment per species dish- Replicate or Petri
 dish 2 to 32: number of germinants in each monitoring day
 "germ_cue.csv" Data for main analysis of germination responses
 to experimental treatments species- taxon scientific name temp-
 temperature treatment. Cold (7/18°C) or Warm (7/24°C) light- light
 treatment. Light is 12h/12h dark/light and Dark is continuous darkness
 total_seeds_dish- is the total seeds sown in each dish dish- Replicate or
 Petri dish germination_total- total seeds that germinated in each petri
 dish by the end of the experiment "legend_point.csv" Data
 containing legends for Figure 3. Cells containing NA mean "Not
 Applicable". species- taxon scientific name Treatment- treatment
 combinations from Pairwise analyses. Treatments were Cold (7/18°C), Warm
 (7/24°C),Light (12h/12h dark/light), Dark (continuous darkness). x and y -
 coordinates for placing the labels label- labels summarizing the results
 from the pairwise analyses to be plotted "occurrence.csv" Data
 containing occurrence data from the field id- block and plot ids combined
 species- taxon scientific name plot- id of 30 x 30 cm quadrats in which
 occurrence data was surveyed, there 150 in total block- iq of block (15 x
 15 m) in which quadrats were placed, there were 10 in total occurrence -
 binary variable for the presence absence of species in each quadrat/block
 combination canopy_cover - the percentage of tree canopy cover at each
 quadrat using a spherical densiometer litter_percent - the percentage of
 litter estimated by overlaying a 100-point grid on quadrat photos and
 counting all intersections covered by leaves or fallen branches
 "seed_mass.csv" Data containing seed mass values for species
 with sufficient germination species- taxon scientific name mean_SM - mean
 values of seed mass (mg)