A personal perspective on four decades of paleolimnology and environmental change research

A personal summary of paleolimnological research activities in the UK and elswehere since the mid 1970s

Palaeoecological evidence for the timing and causes of lake acidification in Galloway, South West Scotland

During the contract period sediment cores from six lakes, three with non-afforested and three with partially afforested catchments, were analysed to enable lake water acidity (pH) to be reconstructed over approximately the past 200 years. The sites are all situated on granitic rocks in the Galloway Hills of S.W. Scotland. The results of diatom analysis show that five of the six lakes have become considerably more acid over this time period and that the acidification process is mainly independent of catchment afforestation effects. {210}^Pb dating of the sediment shows that there has been little change in sediment accumulation rates at sites with non-afforested catchments, but there has been significant increases in accumulation rate at afforested sites associated with erosion caused by pre-planting catchment ploughing. Pollen analysis indicates that no major vegetation change has occurred at the non-afforested sites whilst trace metal analysis of L. Enoch (not funded by this contract) shows elevated levels of Pb, Cu, and Zn 1n the upper, post 1800 sediments. It is concluded that acid precipitation is the most likely cause of acidification at these sites

Acid Lakes in the Galloway Uplands, South West Scotland: catchments, water quality and sediment characteristics

Reports of diminishing salmonid fisheries and increasing acidity of lakes and streams in S.W. Scotland have attributed the cause to low pH precipitation (Wright &Henriksen 1980) and afforestation effects (Harriman & Morrison 1982). In 1981 we initiated a project with CEGB funding to examine the history of lakewater acidity in both afforested and unafforested catchments in the Galloway uplands (see frontispiece). Analysis of diatom remains in lake sediments is used to reconstruct lake pH change over the past 150 years at each site. Sediment chronology is provided by lead-210 dating (Appleby & Oldfield 1978). Contemporary limnological data on water quality and diatom communities has been collected over an annual cycle (1981-82) to aid evaluation of the sedimentary data

Water quality and water availability variations in an upland Galloway loch with special reference to dissolved organic matter and the distribution of benthic diatoms

Upland waters in acid sensitive regions of Scotland are vulnerable to several disturbance processes that most importantly include atmospheric pollution and climate change as well as to local land use. Monitoring in the Round Loch of Glenhead (RLGH) since 1988 has shown that both water acidity and sulphate concentration have declined while the concentration of dissolved organic matter (DOM) has steadily increased. Currently, it is unclear if increasing DOM reflects climate change effects or relief from acid pollution. This report concerns recent research at the RLGH on relating seasonal changes in water supply and coloured dissolved organic matter (cDOM) to the distributions of benthic algae (diatoms). Diatoms are primarily limited by light which in turn varies according to season, water depth and water transparency. cDOM in lake water strongly influences water transparency and our central hypothesis is that benthic diatom distributions are influenced by changes in cDOM concentrations and light availability

Endogenous annexin A1 counter-regulates bleomycin-induced lung fibrosis

PMCID: PMC3212807This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

An enhanced SWAT wetland module to quantify hydraulic interactions between riparian depressional wetlands, rivers and aquifers

This study develops a modified version of the Soil and Water Assessment Tool (SWAT) designed to better represent riparian depressional wetlands (SWATrw). It replaces existing unidirectional hydrological interactions between a wetland and a river/aquifer with a more robust bidirectional approach based on hydraulic principles. SWATrw incorporates a more flexible wetland morphometric formula and a connecting channel concept to model wetland-river interactions. SWAT and SWATrw were tested for the Barak-Kushiyara River Basin (Bangladesh and India). Although the two models showed small differences in simulated stream flow, SWATrw outperformed SWAT in reproducing river stages and the pre-monsoon river-spills into riparian wetlands. SWATrw showed that the observed presence of dry season water in the wetland was due to reduced seepage to the local groundwater table whilst continuous seepage simulated by SWAT resulted in the wetland drying out completely. The new model therefore more closely simulates the hydrological interactions between wetlands, rivers and groundwater

Surface sediment diatom assemblages and water quality in Welsh lakes: brief descriptions of 33 sites selected for study

In May 1987 surface sediment and periphyton samples were collected for diatom analysis from 27 upland lakes in mid- and north Wales (Figure 1). The sites were selected to provide a range of water acidities from circumneutral to strongly acid. The results, together with those collected from other regions in the British Isles, are to be used to produce a UK diatom-water quality data set that will facilitate calibration of sediment core diatom assemblages and reconstruction of past water quality characteristics such as pH (eg. Birks et al. 1990)