Habitat connectivity in agricultural landscapes improving multi-functionality of constructed wetlands as nature-based solutions

TL;DR

This study presents a methodology combining ecological niche modeling and graph theory to identify optimal locations for constructed wetlands that both mitigate agricultural water pollution and enhance habitat connectivity for amphibians.

Contribution

It introduces a novel framework integrating habitat suitability modeling and connectivity analysis to optimize constructed wetlands for pollution reduction and biodiversity support.

Findings

Identified key areas for wetlands that improve amphibian habitat connectivity.

Demonstrated the potential of habitat connectivity assessment to enhance multifunctionality of NBS.

Showed that strategic placement of wetlands benefits both water quality and biodiversity.

Abstract

The prevention of biodiversity loss in agricultural landscapes to protect ecosystem stability and functions is of major importance in itself and for the maintenance of associated ecosystem services. Intense agriculture leads to a loss in species richness and homogenization of species pools as well as the fragmentation of natural habitats and groundwater pollution. Constructed wetlands stand as nature-based solutions (NBS) to buffer the degradation of water quality by intercepting the transfer of particles, nutrients and pesticides between crops and surface waters. In karstic watersheds where sinkholes short-cut surface water directly to groundwater increasing water resource vulnerability, constructed wetlands are recommended to mitigate agricultural pollutants. Constructed wetlands also have the potential to improve landscape connectivity by providing refuge and breeding sites for wildlife, especially for amphibians. We propose here a methodology to identify optimal locations for water pollution mitigation using constructed wetlands from the perspective of habitat connectivity. We use ecological niche modelling at the regional scale to model the potential of habitat suitability for nine amphibian species, and to infer how the landscape impedes species movements. We combine those results to graph theory to identify connectivity priorities at the operational scale of an agricultural catchment area. Our framework allowed us to identify optimal areas from the point of view of the species, to analyze the effect of multifunctional constructed wetlands aiming to both reduce water pollution and to improve amphibian species habitat overall connectivity. More generally, we show the potential of habitat connectivity assessment to improve multifunctionality of NBS for pollution mitigation.