Original Research ARTICLE
Deicing salt pollution affects the foliar traits and arthropods’ biodiversity of lime trees in Riga’s street greeneries
- 1Université de Neuchâtel, Switzerland
- 2University of Latvia, Latvia
- 3WSL Institute for Snow and Avalanche Research SLF, Switzerland
- 4Ecology and Evolutionary Biology, Université de Neuchâtel, Switzerland
Street greeneries and other green spaces within the urban matrix can potentially reduce air pollution and increase urban biodiversity. Yet, these services can be negatively affected by anthropogenic stress factors. In the boreo-nemoral zone, large amounts of salts are spread each year for deicing the pavement. To address the effect of deicing salt on street lines of lime trees and how this cascades up to influence the surrounding arthropod biodiversity, we compared heavily salt-polluted and less polluted sites in the city of Riga, Latvia. We analyzed the impairment of foliar functions and development of aphids’ colonies using a common garden experiment. We found marked variation in the soil physico-chemical properties in polluted versus unpolluted sites. The overall abundance of arthropods, including that of the lime tree aphid specialist, was decreased and, as a consequence, less biotic injury was observed in foliage. The exposure to increased salt levels in the soil caused functional as well as structural injuries within foliage and slowed down the development of aphid colonies. The effects of de-icing salts thus appeared to cascade up through the trophic chain and to negatively affect not only the trees but also the associated arthropod biota. These findings point at the necessity of a wider screening of plant species and cultivars that not only better tolerate anthropogenic stress but also promote the biodiversity in cities.
Keywords: Arthropod biodiversity, Deicing salt, Eucallipterus tiliae, multidisciplinary functional approach, Plant tolerance, Urban Ecology, urban soils
Received: 28 Feb 2019;
Accepted: 11 Jul 2019.
Edited by:Shannon Murphy, University of Denver, United States
Reviewed by:Elsa Youngsteadt, North Carolina State University, United States
Steve Frank, North Carolina State University, United States
Copyright: © 2019 Bouraoui, Cekstere, Osvalde, Vollenweider and Rasmann. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Sergio Rasmann, Université de Neuchâtel, Ecology and Evolutionary Biology, Neuchâtel, Switzerland, firstname.lastname@example.org