A review of present information on the zoogeography of Chironomidae at subfamily and generic levels is given. The known distribution, including some previously unpublished records, of all recognisable genera (307) and subgenera (56) is tabulated according to zoogeographical region. The greatest number of genera is known from the Nearctic (202)

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Passive treatment systems have primarily been used at abandoned mines to increase pH and remove metals from the drainage water. Two pilot-scale treatment wetlands were constructed and monitored at an active lead/zinc mine (Tara Mines) in Ireland to treat alkaline mine water with elevated sulfate and metal levels. Each system comprised three in-series surface-flow cells that contained spent mushroom compost substrate. Typically, aqueous concentrations of 900 mg L -1 sulfate, 0.15 mg L -1 lead, and 2.0 mg L -1 zinc flowed into the treatment wetlands at c. 1.5 L min -1 . During a two-year monitoring period, removal of sulfate (mean of 10.4 g m -2 day -1 (31%), range of 0-42 g m -2 day -1 (0-81%)), lead (mean of 1.9 mg m -2 day -1 (32%), range of 0-6.6 mg m -2 day -1 (0-64%)) and zinc (mean of 18.2 mg m -2 day -1 (74%), range of 0-70 mg m -2 day -1 (0-99%)) were achieved. These contaminants were somewhat associated with the vegetation roots but more significantly with the substrate. Communities of colonizing macroinvertebrates, macrophytes, algae, and microorganisms contributed to the development of a diverse ecosystem, which proved to be a successful alternative treatment process. The interacting processes within the wetland ecosystems responsible for wastewater decontamination are being further elucidated and quantified using a systems dynamic model.

Results of palaeoecological studies involving pollen analytical, chemical and palaeomagnetic investigations on a 3 m core from Lough Doo, NE County Mayo, are presented. The record, which commences shortly after 7000 BP, shows a sharp Alnus expansion coinciding with a decline in finus at 6400 BP, an elm decline taking place in the context of severe soil erosion and the final decline of Pinus occurring as the chemical record indicates onset of severe reducing conditions in the catchment. Pine becomes extinct at or shortly before 3200 BP in the context of increased farming activity and the expansion of blanket bog in the adjacent upland areas. A later feature (c. 1880 BP) is the expansion of Taxus to 7.1 % of total pollen.On the basis of the palynological evidence, it is concluded that there were no major Neolithic Landnam phases, which contrasts sharply with the evidence for widespread woodland clearance and the laying out of extensive and regular field systems in the northern coastal part of County Mayo. In the upper part of the core a severe inversion of I4C dates is recorded. O n the basis of the palaeomagnetic and pollen evidence this began at c. 1500 BP and is considered to have been initiated in the context of woodland clearance and a renewal in farming activity. v Journal of Quaternary Science

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