The effects of turf translocation and other environmental variables on the vegetation of a large species-rich mesotrophic grassland

This paper reports on the translocation of 5.6 ha of a 9.1 ha dry mesotrophic grassland in 1998. For 4 years before and 5 years after translocation, the vegetation was monitored annually by randomised quadrat sampling and compared with an area of the site which remained untranslocated. Associated soil and climatic variables were also monitored. The hypothesis to be tested was that changes in the vegetation ascribable to translocation were of a similar amplitude to those ascribable to other causes. Soil monitoring showed that it had been possible to reconstruct both vegetation and substrate with only minor changes in soil compaction and soil fertility. The frequencies of 28 species in the source meadow in the 4 years before translocation varied significantly. Three areas of the translocated vegetation monitored separately showed significant changes in frequency in a similar number of species, as did the untranslocated area. Species density gradually declined on the translocated turf for the first 4 years after translocation but recovered in the fifth year, although at least one species has so far failed to recover. Multivariate analysis showed that the translocated vegetation diverged from the untranslocated portion for the first 4 years but that this divergence ceased and partially reversed in the final year. The divergence involved an increase in the cover-abundances of several grasses and a parallel fall in a range of forbs. Weather records suggest that this pattern correlates with 4 years without water stress followed by a much drier growing season in the fifth year. It is concluded that there was a definite response to the 1998 translocation which appears to be comparable in severity with the pre-translocation changes in terms of the effects on species frequency. The untranslocated area also changed suggesting that the changes were not all the result of translocation, and the results for the last year of monitoring imply an element of recovery. The results support the use of turf translocation as a restoration technique where the alternative is the complete loss of the site and where the process of reconstructing the functioning of the ecosystem meets certain standards. Monitoring is continuing for 5 more years.