Research and analysis

Anthropogenic influences on the temperature regime in a chalk river

Examination of the temperature regime in the Hampshire Avon, particularly in relation to Atlantic salmon, and the human activities with potential to affect it.



This report, produced in collaboration with English Nature and the Wessex Salmon and Rivers Trust, presents the findings of a preliminary exploration into changing temperature conditions in the River Avon.

The report was commissioned following indications that reduced numbers of Atlantic salmon during hot, dry summers may be linked to high river temperatures. Using existing data sets, literature sources and dedicated water temperature measurements, the study makes a preliminary assessment of the Avon estuary’s summer temperature regime, and explores the likely influence of various human activities on water temperature.

It concludes that, of those activities investigated, the greatest impact on river temperature almost certainly stems from the historic removal of tree cover. The report provides some preliminary management recommendations and highlights a number of areas for further investigation.