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Table 3 List of variables extracted for the systematic review on GMHT crops

From: What are the effects of the cultivation of GM herbicide tolerant crops on botanical diversity? A systematic review protocol

Variable Name Definition Type Closed terms
article_id Unique identification number assigned to each publication Integer No
Author Author(s) of the listed publication. Text No
Crop Common and species name Text Yes
publication_year Year of publication of study Integer No
citation Citation, e.g. journal name, volume and page numbers Text No
title Title of the publication Text No
author_affiliation Type(s) of institutions/organisations that the author(s) are affiliated with Text Yes
author_institute Institution of corresponding author (or of first author if no corresponding author was listed). Text No
funding Funding source Text No
peer_reviewed Indicates whether study was published in a peer reviewed journal. string yes
Location Geoposition or region/country where field study was performed string yes
Site_info Information on previous cropping, rotation, soil type, irrigation etc. string yes
expmt_num Number of experiments within a study (e.g. different locations, years, etc.) string no
data_location Figure number, table number or page number where means and variation were found. string no
was_data_scanned Indicates whether figures were scanned to obtain data values. YesNo yes
GM trait Herbicide tolerance gene engineered into the transgenic crop. string yes
Conv. herb Conventional herbicide comparator treatment string yes
event Transgenic event of the crop tested. string no
transgenic_hybrid_or_var Transgenic hybrid or variety name. string no
nontransgenic _var Non-transgenic comparator variety name. string no
Weed/plant_class taxonomic class string yes
Weed/plant_sub class Monocotyledon or dicotyledon string yes
plant_order taxonomic order string yes
plant_family taxonomic family string yes
plant_genus taxonomic genus string yes
plant_species taxonomic species string yes
plant_finest grouping Finest level of taxonomic resolution reported for the plant(s). string yes
Annual/perennial   string yes
Strata Emergence/establishment E= early, M= midseason, L=late string yes
replicate_data_issues Codes flag for non-independence to be considered for analyses: TGLE=taxonomic group lumped elsewhere; EMUE= experimental means used elsewhere; CMUE=control means used elsewhere; string yes
Plant _stage Stage. string yes
field_location Location of field(s) to the level of specificity provided by the author string no
number_of_fields Number of fields as described by the author. integer no
cultivation Cultivation practices used within the fields (notes on tillage, herbicides, etc.) string no
plot_size Size of replicate plots (in hectares) real no
plot_size_explanation Explanations for any calculations done to obtain plot size string no
is_plot_size_avg Indicates whether the listed plot size is an average or an estimate string yes
was_study_randomized Indicates whether the authors indicated that they randomly assigned replicates to treatments. string yes
planting_date Date on which field plots were planted. string no
first_sample Date on which first sample was taken string no
last_sample Date on which last sample was taken string no
study_duration More detailed description on study duration string no
herbicide_name Brand name of herbicides used. string yes
herbicide_active_ingr Active ingredient for herbicides used. string yes
_spray_rate Amount of active ingredient per spray. string no
mechanism_of_herbicide_app Indicates if herbicide was applied as spray, granule, LV,ULV string yes
num_of_herbicide_app Number of herbicide applications. real no
is_num_of_herbicide_app_avg Indicates if the number of herbicide applications is an average string yes
sampling_method_abbrev Abbreviated description of sampling method string yes
sampling_method_detailed Detailed description of sampling method. string no
sampling_frequency Frequency of repeated samples per replicate field or plot. string yes
number_of_sample_days The number of times that each replicate field or plot was repeatedly sampled over the duration of the experiment. real no
num_subsamples Number of subsamples per true replicate. real no
response_variable_abbrev Major category of response variable. string yes
response_variable_detailed Detailed description of response variable. string no
true_control_sample_size True sample size for control treatment. real no
true_expmtl_sample_size True sample size for experimental treatment. real no
authors_control_sample_size Sample size for the control treatment as stated by the author. real no
authors_expmtl_sample_size Sample size for the experimental treatment as stated by the author. real no
seasonal_or_peak Indicates whether values represent seasonal means across multiple sample days or means from peak days string yes
did-we-calc Indicates whether we calculated the seasonal mean or peak days. YesNo yes
calc_method_seas_mean Explains how we calculated the seasonal mean or peak days string yes
comparison_type Indicates whether the comparison is with conventional treated HT or conventional treated control, minimum tillage vs conventional tillage string yes
control_mean Mean for the control treatment. real no
expmtl_mean Mean for the experimental treatment. real no
control_std_err Standard error for the control treatment. real no
expmtl_std_err Standard error for the experimental treatment. real no
control_std_dev Standard deviation for the control treatment. real no
expmtl_std_dev Standard deviation for the experimental treatment. real no
mean_unit Unit of measurement for the response variable. E.g. weed/seed numbers, biomass, ground cover. string yes
statistical_test_used Statistical test used by author. string yes
is_effect_significant Indicates whether a significant effect was detected by the author. string yes
warning1 Space for remarks for this record string no
  1. Given is the variable name in the database, the definition of the variable, the type, and whether the variable content is restricted to closed (predefined) terms.