A global database to catalogue the impacts of agricultural management practices on terrestrial biodiversity

Abstract

Habitat loss and degradation due to global agriculture land use is a major threat to biodiversity. Identifying agricultural management practices that mitigate these impacts is urgently needed. Thousands of experiments have been conducted worldwide in the last decades to compare the impacts of various agricultural management practices on biodiversity. The magnitudes of difference in biodiversity responses between pairs of agricultural practices, i.e. effect sizes, have now been synthesised in a growing number of meta-analyses. Yet, each meta-analysis generally focuses on a specific type of farming practice and on specific taxonomic groups, or a single region. Meta-analyses could furthermore yield different or sometimes opposite results for the similar research questions. Gathering all the effect sizes in one single dataset helps to critically assess and weigh the available evidence across all studied practices, taxonomic groups and geographical areas, and provide stakeholders a solid base to better inform their decisions. Here, we present a comprehensive dataset of 200 published meta-analyses gathering 1885 effect sizes based on more than 14 000 primary studies. We detail the effect of 8 main individual field practices (e.g. pest and disease management, amendment and fertilisation), 3 agricultural systems (e.g. organic farming, conservation agriculture) and 2 landscape level interventions (i.e. landscape complexity, land-use change). Our dataset covers numerous taxonomic groups over 14 phyla, including animals (e.g. birds, insects), microorganisms (e.g. fungi, bacteria), plants (e.g. trees, weeds). The dataset presented provides a resource to support decision-makers, farmers, and conservation ecologists alike for managing agricultural land for biodiversity.

Keywords: Abundance; Agriculture; Biomass; Land-management practices; Meta-analysis; Richness; Taxonomic groups.

Fig. 1

Cumulative number of meta-analyses included in our database (left panel) showing the effects of agricultural management practices on biodiversity over time, compared to the cumulative number of meta-analyses referenced in the Web of Science over the same period (right panel). Left panel: One meta-analysis may be attributed to one or several types of intervention, depending on the effect size(s) that were extracted from it. We considered 3 types of intervention: ‘Individual practice’ (in orange) for individual management practices (e.g. tillage, use of biocide…), ‘Agricultural system’ (in green) for sets of practices tested together (e.g. organic agriculture) and ‘Landscape’ for landscape-scale management studies (land-use change, landscape complexity). Right panel: We extracted from the Web of Science (in January 2023) the number of references containing “meta-analysis” in all fields, belonging to ‘Environmental sciences’ categories only, which represents 5938 results.

Fig. 2

Total number of effect sizes (in brackets) and mean number of paired data per effect size (box plots, points) for each agricultural management practice (left panel) and taxonomic kingdom (right panel). x-axis: number of paired data used to calculate each effect size, presented in boxplots with jitter points (for clarity, in both panels 28 jitter points in total were hidden as they represent a number between 300 and 800); in orange: individual practices, in green: agricultural systems, in yellow: landscape scale management. y-axis: agricultural management practices (left) and kingdom (right), with in brackets the number of effect sizes. A total of 368 effect sizes are not represented as they do not provide the number of paired data used for their calculation. GMO: genetically modified organism; NA: kingdom not precised or multiple kingdoms are involved within the effect size.

Fig. 3

Decision trees for the first (a) and second (b) step of the screening procedure.

Fig. 4

Flow diagram reporting the different steps of our methodology and the number of relevant literature references retained at each stage.

Fig. 5

Ontology listing the entries available in our database for the type of intervention and the biodiversity outcome (taxonomic group, biodiversity metric). GMO: genetically modified organism.