Beyond a single temperature threshold: applying a cumulative thermal stress framework to plant heat tolerance
Data files
Mar 14, 2024 version files 18.08 MB
-
Airtemp_dfmean_long.csv
-
Cook_CleanData_R_TD_MmonEsoc2023_FINAL.csv
-
Cook_T50_selection_data_Mmon.csv
-
Fig_1.R
-
M.mon-highH2O-2_2-5-2017_processed.csv
-
Neuner_Buchner.R
-
Rainfall_df.csv
-
README.md
-
S1_raw_data_(FvFm).csv
-
Survival_1.txt
-
Survival_2.txt
-
Survival.txt
-
TDT_plants_final.R
-
Thermal_landscape_functions.R
-
Tmaxmin.csv
Abstract
Most plant thermal tolerance studies focus on single critical thresholds, which limit the capacity to generalise across studies and predict heat stress under natural conditions. In animals and microbes, thermal tolerance landscapes describe the more realistic, cumulative effects of temperature. We tested this in plants by measuring the decline in leaf photosynthetic efficiency (FV/FM) following a combination of temperatures and exposure times, then modelled these physiological indices alongside recorded environmental temperatures. We demonstrate that a general relationship between stressful temperatures and exposure durations can be effectively employed to quantify and compare heat tolerance within and across plant species and over time. Importantly, we show how FV/FM curves translate to plants under natural conditions, suggesting that environmental temperatures often impair photosynthetic function. Our findings provide more robust descriptors of heat tolerance in plants and suggest that heat tolerance in disparate groups of organisms can be studied with a single predictive framework.
README: Beyond a single temperature threshold: applying a cumulative thermal stress framework to plant heat tolerance
R Script and data for:
Cook et al. Beyond a single temperature threshold: applying a cumulative thermal stress framework to plant heat tolerance. Ecology Letters, 2024.
Contains 14 files:
(1) Analyses - R scripts to replicate analyses and figures in the manuscript and supplementary material (4 files total):
- TDT plants_final.R
- Thermal landscapes functions.R
- Fig 1.R
- Neuner_Buchner.R
(2) Datasets (7 files total):
Cook_Cleandata_R_TD_MmonEsoc2023_FINAL.csv
For thermal tolerance and temperature duration analysis
Columns:- ID - consecutive row numbers
- Trial - Trial 1, 2 or 3
- Date tested - Date leaves were tested
- Species - M.mon, Myoporum montanum; E.soc, Eucalytpus socialis
- Duration - (min) temperature stress duration; 5, 10, 15 or 30 min
- Temp - (°C), temperature of stress; 28, 48, 50, or 52°C
- Rep - leaf replicate (1-10)
- fvfm_0 - dark-adapted, maximum quantum yield (fv/fm) prior tolerance assay
- fvfm_0-gm - grand mean centered, dark-adapted, maximum quantum yield prior tolerance assay
- fvfm_on - overnight post assay dark-adapted, maximum quantum yield.
M.mon-highH2O-2_2-5-2017_processed.csv
Leaf and air temperature of M. montanum. T-type thermocouples (40 gauge) inserted into leaves, HOBO loggers, and Port Augusta Arid Lands botanic gardens. HW = high water treatment (irrigated), Plants were grown in the ground (red sand dune type substrate).
Columns:- #- sequential row record number
- Date Time
- HW_Tleaf1 - leaf rep 1 temperature (°C), irrigated plant
- HW_Tleaf2 - leaf rep 2 temperature (°C), irrigated plant
- HW_Tleaf3 - leaf rep 3 temperature (°C), irrigated plant
- HW_Tair - air temperature (°C) next to leaves
Tmaxmin.csv
Recorded air temperature for nearest Bureau of Meteorology site-18201, AGBoM (2018). Data for the dynamic model.
Columns:- Code - product number
- Station - Bureau of Meteorology station number
- Year - year of measurement
- Month - month in the year
- Day - day number in the month
- Tmax - (°C) maximun air temperature
- Tmin - (°C) minimum air temperature
- Missingrecord_Tmax - 'y' = yes, 'n' = no. Yes indicates that the blank cell in 'Tmax' (Col F) had no temperature record for that day from the weather station. See Australian Government, Bureau of Meteorology for their data cleaning processes.
- Missingrecord_Tmin- 'y' = yes, 'n' = no. Yes indicates that the blank cell in 'Tmin' (Col G) had no temperature record for that day from the weather station. See Australian Government, Bureau of Meteorology for their data cleaning processes.
Airtemp_dfmean_long.csv
Recorded air temperature at the sampling site (Ibutton). For Supplementary figure S1.
columns:- Day - date of measurement
- Measurement- mean, min or max temperature
- Temp - (°C) air temperature
Rainfall_df.csv
Rainfall from Australian Bureau of Meteorology, AGBoM (2018). For Supplementary figure S1.
Columns:- Date - date of measurement
- Rainfall_mm - rainfall in mm
- missing_record - 'y' = yes, 'n' = no. Yes indicates that the blank cell in col B (Rainfall_mm) had no rainfall record for that day from the weather station. See Australian Government, Bureau of Meteorology for their data cleaning processes.
Cook_T50_selection_data_Mmon.csv\
Data for Supplementary Figure S2.
Columns:- Trial - first trial
- Date - Day/month/year
- Species - Myoporum montanum
- Temp - (°C), temperature of stress; 28, 44, 46, 48, 50, or 52°C
- Duration - (min) temperature stress duration; 5, 10, 15 or 30 min
- Rep - leaf replicate (1-10)
- fvfm_0 - dark-adapted, maximum quantum yield (fv/fm) prior tolerance assay.
- fvfm_on - overnight post assay dark-adapted, maximum quantum yield.
S1 raw data(FvFm).csv
mean Fv/Fm data for 5 species response to temperatures 34 to 64°C and 1min to 512 min. Graciously provided with permission from Neuner & Buchner (2023). Pinus crembra, Picea abies, Larix decidua, Kalmia procumbens, Ranun glacialis.- Table per species with treatment duration (minutes) across the top (columns) and temperature (°C) down the rows. Values are the percentage loss of Fv/Fm with treatment. R code will read this file as is.
(3) text data- dynamic model outputs (3 files; see analysis code)
- Survival.txt - row number, DATE -date time, ta - temperature (°C), alive
- Survival_1.txt - row number, DATE -date time, ta - temperature (°C), alive
- Survival_2.txt - row number, DATE -date time, ta - temperature (°C), alive
References:
- AGBoM (2018a). Climate statistics for Australian Locations: Port Augusta AERO. Available at: http://www.bom.gov.au/climate/data/stations/2018.
- Neuner, G. & Buchner, O. (2023). The dose makes the poison: The longer the heat lasts, the lower the temperature for functional impairment and damage. Environmental and Experimental Botany, 212, 105395.
Methods
Leaf-level data was collected on plants at the Australian Arid Lands Botanic Garden, South Australia, Australia as per methods in the manuscript. Leaf FVFM data on collected detached leaves in response to thermal tolerance assays. Leaf temperature was collected in situ with thermocouples inserted into the leaf epidermis and modeling of leaf and reported air temperatures from the Australian Bureau of Meteorology. See the article for more details.