Relationships between riverine and terrestrial dissolved organic carbon: Concentration, radiocarbon signature, specific UV absorbance.

The transfer of dissolved organic carbon (DOC) from land to watercourses plays a major role in the carbon cycle, and in the transport and fate of associated organic and inorganic contaminants. We investigated, at global scale, how the concentrations and properties of riverine DOC depend upon combinations of terrestrial source solutions. For topsoil, subsoil, groundwater and river solutions in different Köppen-Geiger climatic zones, we compiled published and new values of DOC concentration ([DOC]), radiocarbon signature (DOC), and specific UV absorbance (SUVA).

Determining E. coli burden on pasture in a headwater catchment: combined field and modelling approach.

Empirical monitoring studies of catchment-scale Escherichia coli burden to land from agriculture are scarce. This is not surprising given the complexity associated with the temporal and spatial heterogeneity in the excretion of livestock faecal deposits and variability in microbial content of faeces. However, such information is needed to appreciate better how land management and landscape features impact on water quality draining agricultural landscapes.

Clear and present danger? The use of a yeast biosensor to monitor changes in the toxicity of industrial effluents subjected to oxidative colour removal treatments.

Discharges of coloured effluents into surface waters provide conspicuous evidence of the impact of industry on the environment. The textile industry is an obvious candidate for sources of such discharges. Conventional treatment methods appear to alleviate this situation by removing colour, however the affect on toxicity is less obvious.

A yeast-based cytotoxicity and genotoxicity assay for environmental monitoring using novel portable instrumentation.

An assay capable of simultaneously measuring both general toxicity and more subtle genotoxicity, in aqueous environmental samples, is described. The assay uses eukaryotic (yeast) cells, genetically modified to express a green fluorescent protein (GFP) whenever DNA damage, as a result of exposure to genotoxic agents, is repaired. A measure of the reduction in cell proliferation is used to characterise general toxicity producing familiar EC(50) and LOEC data.