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In February 1993, a snow pillow was installed at Widdibank Fell near Cow Green reservoir (in Upper Teesdale) to monitor snow water equivalent. This paper describes existing snow‐measurement techniques in the UK and the site‐selection process and installation details for the snow pillow. Following a winter of more than 100 days with snow cover at the site, the success of the pillow in representing site and catchment snow conditions and in providing operationally useful snowmelt information for flood warning has been assessed.

Summary The main features of the vegetational history revealed by study of two sets of cores from Dubh Lochan, near Loch Lomond are as follows:  There was a brief pioneer phase during the end of the Younger Dryas period after the disappearance of the Loch Lomond glacier. Dwarf shrubs and herbs, including arctic‐alpines and pteridophytes, predominated.  There followed a brief phase of Empetrum and Juniperus in the earliest Flandrian.  Next came the expansion of tree Betula and then Corylus at 9350 years B.P. Together these dominated for up to 3000 years, with the arrival of Ulmus and Quercus and expansion of the latter, towards the end of the period.  There followed a temporary expansion of Pinus and the development of mixed Quercus forest with Alnus before 6000 years B.P. The Ulmus decline at 4900 years B.P. was well marked.  Major differences in the pollen spectra of the two cores in terms of the regional, extra local and local components occur during the last 4000 to 5000 years B.P. A hydroseral succession from open water through a Salix carr to a Myrica carr was noted only from the marginal core.  Though pollen indicative of human disturbance occurs from the Ulmus decline onwards and expands towards the top of the sequences, the area has stayed under Quercus forest with Alnus and Betula, there having been no substantial disforestation until the last 1000 years.

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Eleven years of weekly observations on the phosphorus cycle in Lough Pieagh are analysed. The data comprised inputs, outputs and lake concentrations of the soluble and particulate phosphorus fractions. It is shown that the particulate phosphorus input quickly sediments to the bottom and the particulate phosphorus in the lake is largely made up of phyt'oplankton. The average pliosphorus retention in the lake was 34 O,l0, similar to the particulate phosphorus input. Climate has a big influence on the phosphorus input and sediment release, both of which varied two-fold. A simulation model suggested that suppression of sediment P release wonld reduce lake winter phosphorus concentrations by an average of 29 0'". Rough grazing19 0 ,, Area 387 kmz Mean depth 8.9 in Volume 3.45 km Retention time 1.24 yr C j Grassland 74 0 -4rable 7 0 0 a) Mean 1941-1970 b) 1979 data C ) Mean 1969-1985 li Int. Rcviie ges. Hydrobiol. 73 (1988) 3