The importance of interaction strength for food web dynamics and ecosystem functioning

Global biodiversity is eroding at an alarming rate, through a combination of anthropogenic disturbance and environmental change. Ecological communities are bewildering in their complexity. Experimental ecologists strive to understand the mechanisms that drive the stability and structure of these complex communities in a bid to inform nature conservation and management. Two fields of research have had high profile success at developing theories related to these stabilising structures and testing them through controlled experimentation. Biodiversity-ecosystem functioning (BEF) research has explored the likely consequences of biodiversity loss on the functioning of natural systems and the provision of important ecosystem services. Empirical tests of BEF theory often consist of simplified laboratory and field experiments, carried out on subsets of ecological communities. Such experiments often overlook key information relating to patterns of interactions, important relationships, and fundamental ecosystem properties. The study of multi-species predator-prey interactions has also contributed much to our understanding of how complex systems are structured, particularly through the importance of indirect effects and predator suppression of prey populations. A growing number of studies describe these complex interactions in detailed food webs, which encompass all the interactions in a community. This has led to recent calls for an integration of BEF research with the comprehensive study of food web properties and patterns, to help elucidate the mechanisms that allow complex communities to persist in nature. This thesis adopts such an approach, through experimentation at Lough Hyne marine reserve, in southwest Ireland. Complex communities were allowed to develop naturally in exclusion cages, with only the diversity of top trophic levels controlled. Species removals were carried out and the resulting changes to predator-prey interactions, ecosystem functioning, food web properties, and stability were studied in detail. The findings of these experiments contribute greatly to our understanding of the stability and structure of complex natural communities.

Sectoral impacts on the diversity of carabid beetles (Coleoptera: Carabidae) and their associated ecosystem service of biocontrol

This thesis aimed to provide an understanding of how human-induced changes in the economic sectors of agriculture and transport affect carabid diversity, potential carabidmediated biocontrol and predator-pest interactions. The research involved both observational and manipulative laboratory and field-based studies. Observational research consisted of two large-scale investigations of (1) the impact of Miscanthus and oilseed rape production (n=45) and (2) the impact of horticultural and ecological based landscaping of roadside verges (n=64). This research is the first record of carabid diversity, potential biocontrol and community assemblage with respect to bioenergy crop production and roadside landscaping in an Irish context and it is also an important addition to the limited knowledge of carabid populations in these ecosystems internationally. Manipulative work involved the examination of the role predator identity, diversity and biomass play in the suppression of pollen beetle larvae (an economically damaging insect pest of oilseed rape in Europe), using a novel experimental design called ‘simplex’. To complement this research, an additional field study on the impact of low and high oilseed rape pesticide management on carabid species richness and abundance, and crop yield, was also conducted. This research is a great contribution to the existing understanding of what constitutes the important components of predator biodiversity and expands the knowledge of the usefulness of carabid predators in the context of pollen beetle larvae control. In particular, the work shows that the abundance or biomass of beetles has an effect that is far larger than the effect of diversity on the capacity of beetles to consume prey. In turn, the field study showed that pesticide applications had little impact on yield, or carabid richness, but that carabid abundance/biomass declined drastically. The work provides compelling evidence that management practices erode the useful components of biodiversity that are essential for the delivery of biocontrol services.

Self-neglect: development and evaluation of a self-neglect (SN-37) measurement instrument

Aim: To develop and evaluate the psychometric properties of an instrument for the measurement of self-neglect (SN).Conceptual Framework: An elder self-neglect (ESN) conceptual framework guided the literature review and scale development. The framework has two key dimensions physical/psycho-social and environmental and seven sub dimensions which are representative of the factors that can contribute to intentional and unintentional SN. Methods: A descriptive cross-sectional design was adopted to achieve the research aim. The study was conducted in two phases. Phase 1 involved the development of the questionnaire content and structure. Phase 2 focused on establishing the psychometric properties of the instrument. Content validity was established by a panel of 8 experts and piloted with 9 health and social care professionals. The instrument was subsequently posted with a stamped addressed envelope to 566 health and social care professionals who met specific eligibility criteria across the four HSE areas. A total of 341 questionnaires were returned, a response rate of 60% and 305 (50%) completed responses were included in exploratory factor analysis (EFA). Item and factor analyses were performed to elicit the instruments underlying factor structure and establish preliminary construct validity. Findings: Item and factor analyses resulted in a logically coherent, 37 items, five factor solution, explaining 55.6% of the cumulative variance. The factors were labelled: ‘Environment’, ‘Social Networks’, ‘Emotional and Behavioural Liability’, ‘Health Avoidance’ and ‘Self-Determinism’. The factor loadings were >0.40 for all items on each of the five subscales. Preliminary construct validity was supported by findings. Conclusion: The main outcome of this research is a 37 item Self-Neglect (SN-37) measurement instrument that was developed by EFA and underpinned by an ESN conceptual framework. Preliminary psychometric evaluation of the instrument is promising. Future work should be directed at establishing the construct and criterion related validity of the instrument.

Comparing impacts of new cropping systems on biodiversity in traditional rural China

This study selected six geographically-similar villages with traditional and alternative cultivation methods (two groups of three, one traditional and two alternatives) in two counties of Henan Province, China—a representative area of the Huang-huai-hai Plain representing traditional rural China. Soil heavy metal concentrations, floral and faunal biodiversity, and socio-economic data were recorded. Heavy metal concentrations of surface soils from three sites in each village were analysed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS, chromium, nickel, copper, cadmium, and lead) and Atomic Absorption Spectrophotometer (AAS, zinc). The floral biodiversity of four land-use types was recorded following the Braun-Blanquet coverage-abundance method using 0.5×0.5m quadrats. The faunal biodiversity of two representative farmland plots was recorded using 0.3×0.3m quadrats at four 0.1m layers. The socio-economic data were recorded through face-to-face interviews of one hundred randomly selected households at each village. Results demonstrate different cultivation methods lead to different impact on above variables. Traditional cultivation led to lower heavy metal concentrations; both alternative managements were associated with massive agrochemical input causing heavy metal pollution in farmlands. Floral distribution was significantly affected by village factors. Diverse cultivation supported high floral biodiversity through multi-scale heterogeneous landscapes containing niches and habitats. Faunal distribution was also significantly affected by village factor nested within soil depth. Different faunal groups responded differently, with Acari being taxonomically diverse and Collembola high in densities. Increase in manual labour and crop number in villages using alternative cultivation may positively affect biodiversity. The results point to the conservation potential of diverse cultivation methods in traditional rural China and other regions under social and political reforms, where traditional agriculture is changing to unified, large-scale mechanized agriculture. This study serves as a baseline for conservation in small-holding agricultural areas of China, and points to the necessity of further studies at larger and longer scales.

Towards a regional understanding of Irish traditional music

The geography of Irish traditional music is a complex, popular and largely unexplored element of the narrative of the tradition. Geographical concepts such as the region are recurrent in the discourse of Irish traditional music but regions and their processes are, for the most part, blurred or misunderstood. This thesis explores the geographical approach to the study of Irish traditional music focusing on the concept of the region and, in particular, the role of memory in the construction and diffusion of regional identities. This is a tripartite study considering people, place and music. Each of these elements impacts on our experience of the other. All societies have created music. Music is often associated with or derived from places. Some places construct or reinforce their identity through the music and musicians through which they are associated. The thesis challenges conventional discourse on regional styles that construct an imagined pattern of regions based on subtle musical differences that may, though are not always, shared by people in that region and focuses on the social networks through which the music is disseminated. The thesis also challenges the abandonment of regional styles and the concept of regions in understanding the complex geographies of Irish traditional music (Morton, 2001). It seeks to find a middle ground between discourse analysis, musical analysis, the experience of music and place, and the representation of music and place. The dissertation is divided into three parts. Part one considers the development of music geography, noting and critiquing the abandonment of useful paradigms in both geography and ethnomusicology in search of new ways of understanding. Of particular interest is the concept of the region but it also considers the study of landscape and the humanist approach in cultural geography. The second part focuses on the discourse and study of regions in Irish traditional music and the various agents and processes that shape the concept of the region in Irish traditional music. The final part presents a case study of the Sliabh Luachra region combining and applying the various perspectives and paradigms drawn from geographical, ethnomusicological and anthropological sources. It attempts to generate an understanding of Sliabh Luachra as a region in the Irish traditional music narrative that is based on a combination of musical, socio-cultural and locational/environmental factors.

Ecology of frontier populations of the invasive grey squirrel (Sciurus carolinensis) in Ireland

The rise in invasive species, together with habitat destruction, is associated with worldwide declines in biodiversity and ecosystem functioning. Management of invasive species, as well as amelioration of invasion impacts, provide challenges to species and ecosystem ecologists and conservation managers. Although any species can become invasive if it is transported to, establishes in and spreads in a new environment outside of its native range, rodents are a particularly frequent invader. Rodent introductions are often inadvertent but are also commonly intentional as these animals are traded and transported as pets and may escape from captivity. Tree squirrel species are attractive to humans and are able to establish populations with only a few founding individuals, making them a group well suited to performing the role of biological invaders. The eastern grey squirrel (Sciurus carolinensis) is the most commonly introduced squirrel species worldwide. This research addressed the grey squirrel invasion and frontier population biology. Novel results were generated through diverse research techniques. Public sighting surveys and hairtube surveys were used to locate the southern frontier of grey squirrel range expansion in Ireland. A 22-month intensive live trapping study of two frontier populations facilitated the collection of personality and demographic data from squirrels in increasing populations. A systematic literature search on grey squirrel demography provided context for the studied populations, among frontier and established introduced populations, as well as those in the native range. Advanced spatially explicit population modeling techniques predicted future range expansion and objectively compared the outcomes of 12 grey squirrel management strategies. The methods and results are discussed in both a basic scientific and applied invasion management context. An improved understanding of the behaviour, population dynamics, and future scenarios at the frontier of species invasions is crucial for managers worldwide and this is provided here for the grey squirrel in Ireland.

ENVIRON 2011: 21st Irish Environmental Researchers Colloquium

The theme of this year’s colloquium is “Towards 2020: Environmental challenges and opportunities for the next decade” which reflects the many environmental targets that have been set for the year 2020 in areas of climate change, renewable energy, water protection and biodiversity. In relation to the latter, we are delighted to have Professor Michael Depledge (Former Chairman of UK Science Advisory Committee on the Environment & Climate Change) at ENVIRON 2011 to deliver the colloquium keynote address on “Health and the Value of Nature”. The colloquium plenary session has a number of high profile speakers who will address the colloquium theme of environmental challenges and opportunities for the next decade including Professor John Sweeney (NUI Maynooth), Ms Laura Burke (Director of EPA’s Office of Climate, Licensing Research and Resource Use) and Mr John Mullins (CEO of Bord Gais). The research programme has 95 oral presentations and 60 poster presentations in the themes of water quality, energy and climate change, marine and coastal research, environmental management, environmental technologies, environment and health, and biodiversity and ecosystems. In addition, for the first year, poster presenters have the opportunity to make a 1 minute oral presentation on their poster during the oral sessions in the relevant theme. The 2011 colloquium also sees an increase the number of workshops and seminars accompanying the programme with an emphasis on training and development for postgraduates in the environmental area. We are particularly pleased to have a link with the Environment Graduate Programme in the “Ocean Studies Workshop” which illustrates how the ENVIRON colloquium can support and benefit from the various graduate programmes currently being developed within Universities. Finally ENVIRON 2011 and the UCC 2011 Law and the Environment symposium have been deliberately scheduled together at the same time and location to allow delegates from both conferences to benefit from each other’s programmes.