Valerie Mccarthy

Dundalk Institute of Technology | DIT · Department of Applied Sciences

Zooplankton communities are the primary conduit of energy from phytoplankton to planktivorous fish in freshwater ecosystems and play key roles in the functioning of these systems. Therefore, they are often proposed as ecological indicators. However, most zooplankton research focuses on a single waterbody or region, and insights from such studies ma...

Body size is a key functional trait that affects many physiological and ecological processes. Among ectotherms, body size patterns are strongly influenced by temperature variation (temperature-size rule). Consequently, climate change is likely to alter body size patterns affecting ecosystem function, particularly in size-structured aquatic communit...

Lakes play a key role in the global carbon cycle, transporting, processing and storing organic carbon (OC) along the land‐ocean aquatic continuum. There are, however, surprisingly few complete lake OC budgets, particularly for certain lake types and geographical areas. An OC budget for Lough Feeagh (Ireland), an oligotrophic, peatland lake in a tem...

The recent development of the Copernicus programme in Europe has ushered in a new generation of operational earth observing satellites. Field-based investigations and monitoring programmes are costly, time consuming and can be logistically challenging in remote or inaccessible locations. The advantages of in situ data monitoring are that they have...

Body size is a key ecological trait that plays a significant role in determining the functioning of size-structured freshwater communities (e.g., predator-prey interactions, energy transfer). Furthermore, body size change has been posited as a universal response to global warming. Despite previous research efforts, most studies on zooplankton body...

Until recent decades, most monitoring of surface waters relied exclusively on samples analysed in the laboratory for ecologically and management-relevant parameters. It is now possible, however, to automatically monitor many parameters using in-situ sensors and to provide remote web-based access to these data. Such data are typically provided at fr...

Extreme precipitation is occurring with greater frequency and intensity as a result of climate change. Such events boost the transport of allochthonous organic matter (allo-OM) to freshwater ecosystems, yet little is known about the impacts on dissolved organic matter (DOM) quality and seston elemental stoichiometry, especially for lakes in warm cl...

To reveal information about the responses of zooplankton to different DOC sources thereby improving the understanding of climate change effects on lake ecosystems

Adaptive neuro-fuzzy inference system (ANFIS) models were developed to elucidate the removal of molybdate reactive phosphate (MRP) and to predict effluent concentrations in integrated constructed wetlands (ICW). The ANFIS models were developed and validated with a four-year dataset from a full-scale ICW treating domestic wastewater. The models high...

Geological heterogeneity across the border counties of Ireland leads to variable levels of resilience in groundwater-dependent ecosystems (GWDEs). In a review of 26 catchments, with contrasting land-use and geology, we investigated the roles that soil and subsoil geochemistry may play in protecting GWDEs against nutrient enrichment from external so...

Contaminants discharging from on-site wastewater treatment systems (OSWTSs) can impact groundwater quality, threatening human health and surface water ecosystems. Risk of negative impacts becomes elevated in areas of extreme vulnerability with high water tables, where thin unsaturated intervals limit vadose zone attenuation. A combined geophysical/...

This study quantified the contributions of different P removal pathways in an integrated constructed wetland (ICW) treating domestic wastewater. Findings over the study period (February 2008 to March 2012) showed average P retention rates of 31 ± 2 mg/m2/day for molybdate reactive phosphate (MRP) and 40 ± 3 mg/m2/day for total P. Near complete P re...

We examined the efficacy of a full-scale integrated constructed wetland (ICW) to remove bulk organic pollutants (BOD5, COD, TSS) and nitrogen (total N, NH4-N, NO3-N) from wastewater. The ICW system was designed to treat domestic wastewater from Glaslough village in Ireland at a loading rate of 1750 population equivalents. During the four-year perio...

Monitoring large-scale treatment wetlands is costly and time-consuming, but required by regulators. Some analytical results are available only after 5 days or even longer. Thus, adaptive neuro-fuzzy inference system (ANFIS) models were developed to predict the effluent concentrations of 5-day biochemical oxygen demand (BOD5) and NH4-N from a full-s...

Monitoring large-scale treatment wetlands is costly and time-consuming, but required by regulators. Some analytical results are available only after five days or even longer. Thus, adaptive neuro-fuzzy inference system (ANFIS) models were developed to predict the effluent concentrations of BOD5 and NH4-N from a full-scale integrated constructed wet...

Nitrogen (N) transformations and removal in integrated constructed wetlands (ICW) are often high, but the contributions of various pathways, including nitrification/denitrification, assimilation by plants and sediment storage, remain unclear. This study quantified the contributions of different N removal pathways in a typical multi-celled ICW syste...

Due to the nature of the phosphorus (P) removal mechanisms associated with constructed wetlands, the sustainability of P treatment is usually of high interest. As a result, a 4-year dataset from a typical multi-celled integrated constructed wetland (ICW) located at Glaslough in Co. Monaghan, Ireland was evaluated to determine the effects of long-te...

The concept of Integrated Constructed Wetlands (ICW) promotes in-situ soils to construct and line wetland cells.The integrity of soil material, however, may provide a potential pathway for contaminants to flow into the underlying groundwater. This study assessed the extent of groundwater quality deterioration due to the establishment of a full-scal...

The Integrated Constructed Wetlands Concept is based on the free flow of water through a series of interconnected wetlands. Each individual wetland, called a wetland cell, is constructed and lined with local on-site soils. The integrity of soil materials, however, may provide a potential pathway for contaminants to flow into the subsoil and consequ...

The paper reports the treatment performance capability, during an on-going full-scale study, which was set to evaluate the novel concept of integrated constructed wetlands (ICW) for domestic wastewater treatment in Ireland. The ICW at the center of this study is located at Glaslough in Co. Monaghan, Ireland. The 3.25 ha ICW comprises of two sludge...

The concept of integratedconstructedwetlands (ICW) uses in situ soils to construct and line their cells. The integrity of soil materials, however, may provide a potential pathway for contaminants to flow into the subsoil. In this study, the rates of infiltration and contaminants loading occurring beneath a full-scale ICW treating domestic wastewate...

A wide range of household sources may potentially contribute to contaminant loads in domestic wastewater. Typically domestic wastewater is combined and transported as a single waste stream, however, there is considerable variation in the pollutant and pathogen content of wastewater derived from different activities within the home (e.g. toilet flus...

The nitrogen (N) removal performance of a 3.25 ha Integrated Constructed Wetland (ICW) treating domestic wastewater from Glaslough village in County Monaghan, Ireland, was evaluated in this study. The ICW consists of two sludge ponds and five shallow vegetated wetland cells. Influent and effluent concentrations of two N species, namely, ammonia-nit...

The nitrogen (N) removal performance of a 3.25 ha Integrated Constructed Wetland (ICW) treating domestic wastewater from Glaslough village in County Monaghan, Ireland, is evaluated in this study. The ICW consists of two sludge ponds and five shallow vegetated wetland cells. Influent and effluent concentrations of two N species, namely, ammonianitro...

The rural population of Ireland relies almost exclusively on on-site treatment systems for disposal of waste water. Septic tank systems, which discharge effluent to ground, constitute the dominant means of waste water disposal. Many of the areas that employ this technology rely on private or small group groundwater supplies, often located in close...

The importance of stoichiometric food quality constraints in influencing zooplankton community structure and distribution in six lakes with categorical variations in alkalinity were investigated by assessing the relationship between seston nutrient content, bulk zooplankton nutrient content and the abundance of individual zooplankton taxa. Stoichio...

Flow-proportional Passive Sensor Validation of Phosphorus and Nitrogen in Irish Rivers (Flow-Pro)

1. According to stoichiometric theory, zooplankters have a species-specific elemental composition. Daphniids have a relatively high phosphorus concentration in their tissues and copepods high nitrogen. Daphniids should, therefore, be more sensitive to phosphorus limitation and copepods more sensitive to nitrogen. A 2-year study of a shallow marl la...