Now showing 1 - 3 of 3
  • Publication
    Regional and farm system drivers of avian biodiversity within agriculture ecosystems
    Farm-wide bird surveys were carried out on 119 grass-based farms located in three separate regions in Ireland during the winter and breeding seasons. Data relating to livestock production system (dairy or non-dairy) and participation in the Irish agrienvironment scheme (AES) at the time, the Rural Environmental Protection Scheme, were collected. GLMMs were used to establish the factors influencing bird populations during the winter and breeding season. Region and farming system had significant effects on avian biodiversity and there were frequently greater numbers on more intensively managed dairy farms, compared with less intensive non-dairy farms. AES participation had no significant effect on bird populations. Our findings demonstrate a clear influence of region and farm system on avian biodiversity, and suggest that the greater resource availability in more intensive farm systems may actually be beneficial for certain components of farmland biodiversity.
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  • Publication
    Interactions between livestock systems and biodiversity in South-East Ireland
    Botanical and arthropod surveys at field level, and bird counts within field boundaries were undertaken on the same random sample of 50 grass-based farms in SE Ireland. Additional data relating to farm system, farm-level nutrient inputs, stocking rates, and participation (or otherwise) in the Irish Rural Environment Protection Scheme (REPS) were collated. Generalized linear models (GLM) showed that farm system was a predominant influence explaining observed biological diversity. Both sward plant and arthropod diversity were greater on non-dairy (drystock) farms, but total arthropod abundance was greater on dairy farm swards. Both the breeding bird abundance and species richness were significantly greater in field boundaries on dairy, compared with non-dairy farms. These insights have relevance to the debate regarding the most effective use of public expenditure on agri-environment policy, and suggest that such incentive schemes need to become more clearly customised to realise the conservation potential of different farming systems.
      1296Scopus© Citations 24
  • Publication
    Different bioindicators measured at different spatial scales vary in their response to agricultural intensity
    Ecologically, potential bioindicator taxa operate at different scales within agricultural ecosystems, and thereby provide a means to investigate the influence of changing management practice on biological diversity at different scales within the agro-ecosystem. Surveys of grassland plant species at field level, parasitoid Hymenoptera at the field and farm scale, and bird populations and habitats at farm scale were carried out on 119 grass-based farms across three regions in the Republic of Ireland. In addition, habitat richness and aquatic macroinvertebrates were quantified at landscape scale. Agricultural intensity on the surveyed farms was quantified by mean farm stocking rate, calculated as livestock units per ha (LU/ha), and generalised linear mixed models used to evaluate relationships between stocking rate and the incidence of chosen bioindicator groups. Field scale bioindicators (plant species richness and parasitoid taxon richness and abundance) were negatively associated with mean farm stocking rate. Over much of its observed range, mean farm stocking rate was positively associated with total bird species richness and abundance, and the species richness and abundance of farmland bird indicator species recorded in the winter season. However, these relationships were quadratic, and above a relatively high upper limit of 2.5–3.5 LU/ha, further increase in farm stocking rate had a negative influence. Results demonstrate that different bioindicators measured at different spatial scales vary in their response to agricultural intensity. The lack of a consistent bioindicator response to farm stocking rate suggests that within predominantly farmed regions, maximising biodiversity requires a careful targeting and monitoring with bioindicator taxa that are informative of influences at relevant operational scales. The insights provided may then be much more informative for the design and implementation of agri-environment measures that maximise biodiversity within farmed landscapes.
      1094Scopus© Citations 24