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Evaluation of conservation status of roadside verges and their vegetation in North England

Akbar K., Hale W., Headley A., Ashraf I.

Polish Journal of Ecology

2010

Vol. 58, nr 3

459-467

The roadside verges and their vegetation in selected counties of north England were evaluated for their conservation status. Thirty five different road sections each 50 m long along different A and B class roads were surveyed and the criteria selected for conservation evaluation included verge area, plant diversity, species richness, disturbance, presence of rare species and structure of hedges. A field assessment sheet was prepared in which, for each factor, a numerical rating system was used. For each factor, information was recorded to help the surveyor in choosing the appropriate score for that site. The rarity of recorded species was determined from the published sources. Most of the surveyed verges (54%) are of low conservation value, 40% are of medium conservation value and only 6% have high conservation status. Despite the unsatisfactory situation, there is considerable potential for using roadside verges for nature conservation because medium class verges could be improved by adopting sound management techniques.

Floristic composition and environmental determinants of roadside vegetation in Northern England

Akbar K., Hale W., Headley A.

Polish Journal of Ecology

2009

Vol. 57, nr 1

73-88

The roadside vegetation in some counties of north England (north and west Yorkshire) was studied to determine the community structure according to the British National Vegetation Classification (NVC) and main environmental factors influencing its composition. The data from Phytosociological survey (699 quadrats) and from the physico-chemical analyses of 233 soil samples from 35 sites were obtained. Both the classification (TWINSPAN & MATCH) and ordination programs (Canonical Correspondence Analysis) were used. The roadside vegetation is mainly dominated by few grasses (Arrhenatherum elatius, Festuca rubra, Dactylis glomerata, Lolium perenne, Poa trivialis, Elymus repens, Holcus lanatus) and their associated herbs (Cirsium arvense, Heracleum sphondylium, Urtica dioica). Five NVC Mesotrophic grassland communities (Arrhenatheretum elatioris community MG1, Lolium perenne-Cynosurus cristatus grassland MG6, Lolium perenne leys MG7, Holcus lanatus- Deschampsia cespitosa grassland MG9, Festuca rubra-Agrostis stolonifera-Potentilla anserina grassland MG11) and one Upland Festuca ovina-Agrostis capillaris-Galium saxatile grassland, U4 were identified which in general, exhibited good fit with the typical NVC units. Altitude, pH, potassium, sodium and road age were found to be the main variables affecting the roadside vegetation. By relating the floristic composition with ecological characteristics of the roadside verges, three kinds of pattern of variation are observed. The first pattern is related to regional or geographical characteristics and the second pattern of variation exists across the width of the road verges showing a zonal pattern of plant distribution. The third scale of pattern is active at the local level including micro-environmental conditions, e.g., local edaphic variables.