# Arthropod biodiversity loss from nitrogen deposition is buffered by natural and semi-natural habitats

## TL;DR

Nitrogen pollution harms arthropod diversity, but natural and semi-natural habitats can help reduce these negative effects.

## Contribution

This study demonstrates that natural and semi-natural habitats buffer arthropod biodiversity loss from nitrogen deposition.

## Key findings

- Nitrogen deposition significantly reduces arthropod species richness and abundance.
- The strongest negative effects occur in less-modified habitats.
- Semi-natural habitats mitigate biodiversity losses from nitrogen deposition.

## Abstract

Nitrogen (N) deposition is known to strongly modify biogeochemical cycles and trophic interactions, in turn altering ecosystem functioning and plant diversity around the globe. However, our understanding of N deposition effects on arthropod diversity remains limited. Here, we investigate how N deposition impacts the diversity of arthropods by combining biodiversity data from the PREDICTS database with data on global N deposition and land cover using mixed-effects models. We then explore the potential for semi-natural and natural habitats (‘SNH’) to buffer against potential N deposition-linked biodiversity losses. N deposition has a negative effect on arthropod biodiversity. Both, species richness and abundance are significantly reduced in areas of high levels of N deposition when compared to areas of low N deposition, with responses varying across different land-use types. The strongest negative effects of N deposition on arthropod diversity were observed in locations where the local land use entails the least anthropogenic modification. At the same time, with the exception of cropland-dominated landscapes, increases in the amount of SNH in the surrounding landscape reduced arthropod biodiversity losses associated with N deposition. We conclude that SNH can play an important role in mitigating the negative effects of N deposition on arthropod diversity, with the conservation and creation of these habitats promoting arthropod diversity even under high levels of N deposition.

Nitrogen deposition reduces arthropod species richness and abundance, especially in less-modified habitats, highlighting its threat to biodiversity. This study shows that natural and semi-natural habitats can buffer against these losses, emphasizing their conservation value in mitigating nitrogen deposition’s negative effects on arthropod diversity.