Monitoring the Ranunculion Habitat on the River Itchen: Practical Application and Constraints

Abstract

The UK government has an obligation to monitor the condition of EUNIS habitat 3260 “Water courses of plain to montane levels with the Ranunculion fluitantis and Callitricho-Batrachion vegetation”. To assess the potential of the MTR data collection method to provide data for this monitoring, a study was carried out by the Environment Agency on the River Itchen SAC in Hampshire involving data collection in the spring, summer and autumn each year from 2004 to 2008. Data analyses included calculation of trends in MTR scores for each survey data-set, comparison against traditional concepts of conservation value and comparison of data on water-crowfoots. MTR scores were inconsistent and it seems unlikely that that they indicate changes in trophic state. Data were unsuitable for assessment against traditional concepts of conservation value as they do not relate to comparable habitats and specifically exclude habitats outside the channel. The taxonomy of the water-crowfoots, combined with the fact that data do not relate to phytosociological units, means that they cannot be used to demonstrate trends in the abundance or health of these plants. The conclusion was reached that MTR data collection method is not a suitable means of collecting data toward monitoring the condition of EUNIS habitat 3260.