Browsing Faculty of Medicine, Dentistry and Life Sciences by Subjects
Now showing items 1-4 of 4
Biodiversity in the North West: The slime moulds of CheshireThe county of Cheshire, in its broadest, historical sense, has a rich diversity of wildlife, linked to a varied geology and land use. This is an account of a group of strange but fascinating organisms, the slime moulds, which straddle the boundaries between fungi and protozoans. After a short introduction to the biology and ecology of slime moulds, the physical and ecological environment of wider Cheshire is described. The main body of the work is a detailed catalogue of all the species ever recorded in the district. The records date back into the 19th century but are mostly concentrated in the last 40 years, since the author came to Chester. There are more than 90 maps, on a 5 km grid square base, of the commoner species.
The classification and management of limestone pavements - an endangered habitatThis thesis describes an in-depth study of limestone pavements across North West England and North Wales. The aim was to combine elements of geodiversity and biodiversity in order to create a holistic limestone pavement classification to inform future management. A field-based research protocol was used to assess a stratified random sample (46 pavements), accounting for approximately 10% of the limestone pavements in the geographical area. Detailed analyses of key elements are presented, along with important issues that continue to pose threats to this Annex One Priority Habitat. This research resulted in a comprehensive classification, using TWINSPAN analysis and Nonmetric Multidimensional Scaling, identifying six distinct holistic functional groups. The prime factors driving limestone pavement morphology, and hence the classification, were established to be lithology, proximity to structural fault, altitude and human intervention, particularly in terms of grazing intensity. Three upland, open limestone pavement classes were formed. Of these, the richest in terms of geodiversity and biodiversity was the group with the thickest bedding planes and hence the deepest grikes, typically greater than 1m. The class that was most species-poor was "at the highest altitude (above 450m), formed on the thin limestones of the Yoredales. These were characterised by shallow, wide grikes. The third upland limestone pavement group had mid-range grikes, generally 0.5-1m in depth, and small clints. Two wooded classes were identified. One was a lowland 'classic' wooded limestone pavement group with deep, narrow grikes and shallow soils. Indicator species included Juniperus communis and Taxus baccata. The second wooded group was situated proximal to a major structural fault. In this group the pavement dip ranged between 10°-40° with well-runnelled clints that were heavily moss-covered. The sixth group was low altitude, proximal to the coast, characterised by low moss growth, un-vegetated clints and the presence of Ulex europaeus. Conservation management was identified as key to the quality of the limestone pavement habitat and this thesis identifies best management practises and links these to the holistic limestone pavement classification. Finally, as a sample case study, this thesis presents mollusc species and diversity from eleven of the Yorkshire limestone pavements. Analysis establishes significant links between geodiversity and mollusc populations, with key drivers for mollusc communities echoing those of plant species on limestone pavement.
Grike-roclimatesThis journal article discusses data collected at two north Wales sites that demonstrates that the direction of grikes makes a significant difference on the biodiversity of limestone pavements.
Microclimate & limestone pavement biodiversity: A pilot project to look at the longterm effects of grike orientation on microclimate and biodiversity in North WalesA long-term project (two years initially) was set up to produce a valuable database of microclimate data across two complete seasonal changes through two winter and summer soltices. The results of the project to date are: grike orientation has the potential to greatly affect the vegetation within the grikes and influence both the timing of its germination, growth and development; the bottom of the grike sufferts less temperatire fluctuation than the surface; there is a significant difference in the solar ration at 57 cm depth between the winter solstice and Mid February 1999; the range of bottom temperatures is significatnly higher in the north-south grikes during the winter months; north-south grikes suffer lower minumum temperatures during the autumn months. Grikes at Y Taranau and Bryn Pydew nature reserve were analysed.