Showing papers in "Biology and Environment-proceedings of The Royal Irish Academy in 2013"

Impact of Soil Type, Biology and Temperature on the Survival of Non-Toxigenic Escherichia Coli O157

Abstract: The occurrence of microbial enteropathogens in the environment can represent a serious risk to human health. The fate of enteropathogens introduced into the soil environment is dependent on a wide range of complex interacting environmental factors. While the effect of abiotic factors on enteropathogen survival has been widely examined, the interaction of enteropathogens with the soil microbial community is poorly understood. This study investigated the effect of soil biology and soil type on the survival of a non-toxigenic strain of Escherichia coli O157 under different temperature regimes. Soil microcosms of two soil types, with and without an intact microbial community, were inoculated with the enteropathogen surrogate, and survival was determined over a 64-day period, encompassing a shift from cold to ambient temperatures. In both soil types bacterial numbers decreased in soil with an intact microfl ora, while in the absence of an intact community E. coli populations increased. This effect was temperature specifi c, with E. coli populations remaining stable at low temperature, regardless of treatment. Soil type was of importance in survival at both cold and ambient temperatures. This work highlights the signifi cance of the soil microbial community in suppressing enteropathogens in soil, and of investigating die-off in a multi-factorial manner.

Geomycology: Fungi as Agents of Biogeochemical Change

Abstract: Geomycology is the study of the roles of fungi in geological processes. The biogeochemical importance of fungi is significant in several areas, including nutrient and element cycling, rock, mineral and metal transformations, bioweathering and mycogenic biomineral formation. Such processes can occur in aquatic and terrestrial habitats, but it is the terrestrial environment where fungi probably have the greatest geochemical influence. Of special significance are the mutualistic relationships with photo trop hie organisms: lichens (algae, cyanobacteria) and mycorrhizas (plants). Central to many geomycological processes are transformations of metals and minerals, and fungi possess many properties that effect changes in metal speciation, toxicity and mobility, as well as mineral formation or mineral dissolution or deterioration. Some fungal transformations have potential applications in environmental biotechnology, e.g. metal and radionuclide leaching, recovery, detoxification and bioremediation, and in the production or deposition of biominerals or metallic elements with catalytic or other properties. Metal and mineral transformations may also result in adverse effects when these processes result in spoilage and destruction of natural and synthetic materials, rock and mineral-based building materials (e.g. concrete), biocorrosion of metals, alloys and related substances, and adverse effects on radionuclide speciation, mobility and containment.

Do Irish forests provide habitat for species of conservation concern

Abstract: The importance of plantation forests for biodiversity conservation is greatest in landscapes that have experienced significant loss of natural forest ecosystems and the plantation forest estate continues to expand, as is the case in Ireland. We investigated the role of plantation forests in supporting forest plants, invertebrates and birds of conservation concern in comparison to semi-natural woodlands in Ireland. Of the 169 vascular plant species, 97 bryophyte species, 162 spider species, 159 beetle species and 36 bird species recorded 5, 3, 9, 1 and 5 species of conservation concern, respectively, were recorded. Many of these were found in semi-natural woodlands, highlighting the importance of the retention or restoration of these habitats for forest biodiversity. A number of species of conservation importance were also recorded in plantation forests demonstrating that the role of these forests in the provision of habitat for biodiversity conservation should not be overlooked.

Temporal changes in codium spp in lough hyne with records for the southern irish coast

Abstract: Surveys of non-indigenous species (NIS) typically concentrate on the establishment and expansion phases of population dynamics. Our study, in contrast, investigated the status of an invader that has declined to low levels throughout much of the British Isles. The green macroalga Codium fragile ssp. fragile (Suringar) Hariot appeared in the British Isles in the 1800s and probably entered Lough Hyne, County Cork, Ireland in the 1930s. It proliferated on Irish shores in the 1940s to 1970s, but has declined to low levels in the region. Broad-scale surveys in County Cork, SW Ireland (2002-2005) and extensive surveys (2001-2011) within Lough Hyne indicate that the introduced alga has declined substantially since earlier decades. These results are consistent with other studies on NE Atlantic shores indicating a long-term decline.

Assessing the influence of a range of spring meteorological parameters on tree phenology.

Abstract: The timing of phenological phases, such as leaf unfolding of trees, is partly driven by the weather. The impact of weather on the spring phenology of a selection of tree species in the phenological garden at Valentia Observatory, Caherciveen, County Kerry, Ireland, for the period 1967-2004 was assessed. In particular, the beginning of the growing season (BGS), as determined by the date of leaf unfolding, was considered. The impact on BGS of a range of meteorological parameters and derived parameters, including minimum, maximum and mean air temperature (°C), soil temperature (°C), rainfall (mm), sunshine (hours), number of air frost days and number of rain days was investigated. These parameters were averaged or summed over the months of February, March and April and linear regression analysis with BGS was carried out for several tree species. The results showed that the regression coefficients of BGS on minimum air and soil temperature were highest, with Populus canescens and Populus tremula showing the strongest relationships. Temperature parameters were found to be more important in driving advancing phenology than any other meteorological parameter tested.

The Cryptogenic Red Alga Bangia Atropurpurea in Lough Derg, River Shannon, Ireland

Abstract: The filamentous and euryhaline red alga Bangia atropurpurea (Rhodophyta, Bangiophyceae) is a littleknown member of the Irish aquatic flora. Although a common freshwater species in the northern hemisphere, it seems that the lower Shannon Navigation is one of the principal freshwater localities for the species in Ireland. It was recorded from thirteen sites in Lough Derg in 1972 and in the 2010 survey reported here at 40 sites including islands and navigation buoys as well as on lock gates. It attaches to rocks and other hard surfaces immediately above and below the waterline. It may have been introduced to Lough Derg on the hulls of commercial vessels. Changes in climatic conditions, eutrophication, competition from other filamentous algae and fluctuating lake levels are all pressures that could affect the sustainability of Bangia within the Shannon Navigation. Nevertheless, this study shows that B. atropurpurea has persisted for at least 40 years in Lough Derg and remains widespread despite highly variable environmental conditions.