In this Issue

Abstract

i DOI: https://doi.org/10.3318/BIOE.2018.16 Biology and Environment: Proceedings of the Royal Irish Academy,Vol. 118, No. 3, i–ii (2018). © Royal Irish Academy Cite as follows: Osborne, B. 2018 In this Issue. Biology and Environment: Proceedings of the Royal Irish Academy 2018. DOI: 10.3318/ BIOE.2018.16 IN THIS ISSUE Bruce Osborne Using zebrafish as novel biomarkers Despite the best intentions and the introduction of a range of legislation often associated with significant financial penalties, pollution is still having a significant impact on natural ecosystems.As well as the continued presence of long-known pollutants, new industrial applications can result in new pollutants or the unexpected appearance of pollutants thought to have largely disappeared. Detecting the critical levels at which a particular pollutant has an impact is, however, no mean feat as these can be below the detection levels of many chemical procedures and/or depend on the use of expensive instrumentation and manpower. Many laboratories have, therefore, turned to alternative, cheaper and arguably more sensitive approaches for the identification and assessment of pollutants. One such approach uses zebrafish (Danio rerio) for a wide range of medically-­ related purposes as well as for assessing the effects of aquatic pollutants.There are several advantages in using zebrafish: they are easily cultured, develop rapidly and generally prove to be efficient when used in monitoring the metabolic and developmental effects associated with many inorganic and organic pollutants in water.As Akbulut et al., in this issue show, the organosulphur compound Thiourea dioxide has dramatic effects on the reproductive physiology of zebrafish, causing a disruption to ovary tissues and an inhibition of follicle development. Thiourea dioxide has a wide range of uses, including industries involved in leather, paper and textile production. As well as being a strong reductant it is also used as a decolourising agent in paper recycling and the printing of textiles. Given the current emphasis on paper recycling and the fact that the effects of pollutants on zebrafish can be extended to vertebrate development and reproduction in general, this would appear to be a significant cause of concern. Hedgerow trees Hedges are often considered a quintessential part of the farmed landscape in many northern temperate countries, giving rise to a mosaic of enclosed fields.The origins and functions of hedges are many and varied: some may reflect the remnants of past woodland, whilst others may have been deliberately planted to mark field boundaries or manage livestock. Many hedgerows in the UK are the result of the enclosures act (1760–1820), although others may even go back as far as Tudor times. Recent years have seen a significant decline in the extent of hedgerows due to field enlargements and the absence of proper management,coupled with a lack of appreciation of their ecological value.Hedgerows often contain a number of tree species, the importance of which has increased due to widespread deforestation. However, the status of these trees is largely unknown, and anecdotal information suggests that many are in decline,so that they may have a low value.In a survey conducted by Spaans et al., in this issue, the most common hedgerow tree in Northern Ireland was found to be ash (Fraxinus excelsior), which made up ~57% of the total trees­ surveyed. Rowan (Sorbus aucuparia) was found to be in the top six of the most common trees surveyed but over 30% of these displayed symptoms of declining health. In comparison another common tree species,Birch (Betula spp.) had a low percentage of unhealthy individuals. Older trees, isolated single trees and trees in hedgerows with a large number of connections to other hedgerows were shown to have a higher incidence of disease,whilst tree plantings next to roads were not associated with a higher incidence of pathogen attack.The authors conclude that many farmland hedgerow trees are in a poor condition and that further epidemics would lead to a significant loss of the ecosystem services provided by hedgerow trees. I think a wider message here is that retaining hedgerows/hedgerow trees per se is not sufficient in itself; to properly maintain the services they can potentially provide, hedgerows require appropriate management interventions. In the...