M. Sheehy Skeffington

A comparison of the efficacy of pond-net and box sampling methods in turloughs - Irish ephemeral aquatic systems

Two methods were used to sample aquatic macroinvertebrates in three turloughs. Turloughs are systems that flood periodically from groundwater, in response to local rainfall patterns and contain rare aquatic species and assemblages. The first method used a standard pond net that was swept through the water column, while the second involved fixing a rectangular, open-bottomed box to the substrata and removing all organisms with a net. Similar overall sampling effort was applied to each method and individual box samples were found to take longer to gather than pond net samples. The box method, however, gave the maximum yield for a given sampling effort. Significantly more beetle species and individuals were recorded per unit area of bottom at all three turloughs using the box method. Multivariate analysis segregated samples, firstly according to site and secondly, with respect to method. The box method is a viable alternative to sampling with a pond net. It is more quantitative, objective, specific and reliable. This is particularly important in habitats distinguished by rare species and assemblages, and for which monitoring is driven by legislative needs.

The flora and carabid beetle fauna of a mature and regenerating semi-natural oak woodland in south-east Ireland

Abstract An investigation of the plant and carabid beetle communities of a mature and adjacent regenerating oak woodland site was carried out from June to September (1999) in County Wexford, south-east Ireland. Phytosociological classification (using 10 m ×10 m quadrats) identified the mature site as belonging to the coryletosum sub-association of the Blechno–Quercetum association. Vegetation was recorded in ten 2 m ×2 m quadrats at each site within which pitfall traps were placed to sample carabids. Median plant species richness per quadrat was greater in the regenerating site (11) than in the mature site (9.5), although this was not statistically significant. The median species richness of carabids per pitfall trap in the mature site (6) was significantly greater than in the regenerating site (3.5) at P

RIPARIAN ZONE CREATION IN ESTABLISHED CONIFEROUS FORESTS IN IRISH UPLAND PEAT CATCHMENTS: PHYSICAL, CHEMICAL AND BIOLOGICAL IMPLICATIONS

COFORD (The National Council for Forest Research and Development in Ireland) & coordinated by Coillte Teoranta and Marine Institute

Growth performance of an inland population of Plantago maritima in response to nitrogen and salinity

The inland distribution of Plantago maritima in Ireland and Britain is strongly western and generally associated with base-rich soils or with flushes in more acidic upland soils. Plants from an eastern Irish salt marsh and from an inland population growing on shallow calcareous soils in east County Clare, Ireland, were grown in culture solutions with a range of seawater dilutions (10–100%) and nitrogen (2.8–140 ppm N) concentrations added as ammonium nitrate. A low nitrogen supply (2.8 ppm N) resulted in very low dry matter production but with increased nitrogen, plant growth increased, even of inland population plants in 50% seawater. Some inland plants survived 100% seawater, but growth was much reduced. The relatively high salinity tolerance of this inland population is discussed.

Distribution and habitats of Erica mackayana and Erica × stuartii (Ericaceae): new insights and ideas regarding their origins in Ireland

Erica mackayana has an unusual disjunct distribution in Europe, as it occurs only in Ireland and northern Spain and is thus known as a Hiberno-Lusitanian species. In Ireland, it is confined to localised areas in the west coast counties of Donegal, Mayo, Galway, and Kerry, where it occurs in lowland, or Atlantic, blanket bog habitat. Detailed mapping, in all of the six known Irish sites, of the distribution of E. mackayana and its hybrid with E. tetralix, E. × stuartii here shown for the first time, reveals a specific pattern of occurrence especially for E. mackayana. This species very rarely occurs more than 1 km from a track or road, whereas the hybrid is more widespread throughout the adjacent bog. Since E. mackayana does not set seed in Ireland and therefore relies on vegetative propagation, its spread at any site is limited, though much increased by human activity. All the sites are in relatively remote areas near the Atlantic coast, and we suggest here that E. mackayana may well have been introduced to Ireland through trade, possibly even smuggling, of goods from northern Spain.Erica mackayana has an unusual disjunct distribution in Europe, as it occurs only in Ireland and northern Spain and is thus known as a Hiberno-Lusitanian species. In Ireland, it is confined to localised areas in the west coast counties of Donegal, Mayo, Galway, and Kerry, where it occurs in lowland, or Atlantic, blanket bog habitat. Detailed mapping, in all of the six known Irish sites, of the distribution of E. mackayana and its hybrid with E. tetralix, E. × stuartii here shown for the first time, reveals a specific pattern of occurrence especially for E. mackayana. This species very rarely occurs more than 1 km from a track or road, whereas the hybrid is more widespread throughout the adjacent bog. Since E. mackayana does not set seed in Ireland and therefore relies on vegetative propagation, its spread at any site is limited, though much increased by human activity. All the sites are in relatively remote areas near the Atlantic coast, and we suggest here that E. mackayana may well have been introduced ...