Code and data for: Global synthesis reveals systematic variation in trophic transfer efficiency across and within ecosystems
Data files
Apr 30, 2026 version files 580.94 KB
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distribution_model.R
7.49 KB
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distribution.csv
135.52 KB
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DOC_data.csv
419 B
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ecopath_model.R
3.82 KB
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ecopath.data.csv
43.83 KB
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environmental_factors.R
11.48 KB
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figure_2_S3.R
17.26 KB
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figure_3_S5.R
19.78 KB
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figure_4.R
6.18 KB
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figure_S1.R
9.67 KB
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figure_S2.R
22.53 KB
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figure_S4.R
4.59 KB
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figure_S6.R
3.69 KB
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Light_data.csv
3.16 KB
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mixed_model.CSV
236.82 KB
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mixed_model.R
10.98 KB
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Nutrient_data.csv
7.90 KB
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PP_data.csv
665 B
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predator_data.csv
2.56 KB
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README.md
4.43 KB
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study_information.xlsx
28.15 KB
Abstract
We conducted a comprehensive literature search using both ISI Web of Science and Scopus databases on May 31, 2025. The search yielded a total of 1543 articles, including 1151 unique entries. We then adopted a cross-search strategy and implemented a supplemental literature filtering process based on citation relevance using the following predefined set of criteria: (i) TTE values must be estimated directly from empirical data rather than indirectly from statistical fitting or optimization (e.g., Ecopath models); (ii) energy/nutrient representation should employ flux measures such as ingestion, assimilation, and production rather than biomass; and (iii) TTE should be assessed using the ratio of the same metric between adjacent trophic levels (e.g., productionn+1 / productionn) rather than focusing solely on its components, such as predation efficiency, assimilation efficiency, or growth efficiency. Based on these criteria, we identified 122 studies for our analysis, which contributed a total of 1,849 estimates of TTE (i.e., samples for our analysis). To understand the drivers of TTEe, we examined both ecosystem-level (e.g., ecosystem type, ecosystem origin, and temperature) and species-level (i.e., resource type, consumer type, and trophic level) factors.
Dataset DOI: 10.5061/dryad.ht76hdrv6
Description of the data and file structure
In this study, we present a comprehensive synthesis of the literature reporting TTE values based on empirical estimates of consumer and resource production (or their assimilation or ingestion) across ecosystems. To do so, we performed a meta-analysis of the published literature. Our final dataset included 122 studies and a total of 2,052 TTE estimates. Any empty cells represent data not available.
Files and variables
Data
1. study_information.csv: Contains information about the studies used in our analysis.
· new.id: The study identifier.
· Original.appellation: The term used in the articles to refer to trophic transfer efficiency.
· Original.function: The function of trophic transfer efficiency as defined in the articles.
· Our.function: The function of trophic transfer efficiency used in our study.
· Our.Definition: The definition of trophic transfer efficiency as applied in our study.
· Parse.from: The source of the data.
· flux.estimate.method: The method used to measure trophic transfer efficiency.
2. mixed_model.csv: Contains data on energy transfer efficiency and the corresponding ecosystem- and species-level factors.
· eff: The value of trophic transfer efficiency.
· Ecosystem.origin: The ecosystem type as reported in the original articles.
· Ecosystems/Ecosystem.type/Ecosystem.type2: Different classifications of ecosystem types.
· resource: Types of resources involved in the energy transfer.
· consumer: Types of consumers in the food web.
· TL: Trophic levels.
· Definition: The definition of trophic transfer efficiency used in our study.
· substance/substance 2: The substance involved in trophic transfer efficiency.
· Temperature: The temperature (degree C) value based on the recorded location and time as specified in the articles.
· Temp_from: The source from which the temperature data were obtained.
· Context: The site, time, and treatment conditions.
· stoich.pp: "1" indicates data from only predator or prey stoichiometry; "2" indicates data from both.
· unit: The unit of the stoichiometry data.
· CN.prey/CN.predator/CP.prey/CP.predator: The C:N or C:P ratio of predator or prey.
3. distribution.csv: Contains data on both energy and nutrient transfer efficiency.
4. ecopath_data.csv: Ecopath model data.
· FW: Food web identifier.
· Ecosystem: Ecosystem type.
· TL: Trophic levels.
· TTE: Trophic transfer efficiency.
5. environment:
· DOC_data.csv, Light_data.csv, Nutrient_data.csv, PP_data.csv, predator_data.csv: These files contain energy transfer efficiencies under different experimental treatments.
Code/software
1. mixed_model.R: R script for linear mixed-effects models to test the influence of ecosystem- and species-level factors on trophic transfer efficiency.
2. distribution_model.R: R script for linear mixed-effects models comparing differences among various definitions and substances of energy or nutrient transfer efficiency.
3. ecopath_model.R: R script for linear mixed-effects models examining the effects of ecosystem type and trophic level on energy transfer efficiency in Ecopath models.
4. environmental_factors.R: R script for linear mixed-effects models examining the effects of experimental treatments on energy transfer efficiency.
5. figure.R: R script for generating figures and the corresponding tables. First run the four R scripts listed above, followed by figure.R to generate the figures.
Access information
Other publicly accessible locations of the data:
- None
Data was derived from the following sources:
- None