Home About us Contact
|
Home About us Contact | ||
|
|
||
Cover Variables (cover + variable)
Selected AbstractsGround beetle species (Coleoptera, Carabidae) associations with land cover variables in northern England and southern ScotlandECOGRAPHY, Issue 4 2004M. D. Eyre Distribution data concerning 172 ground beetle species derived from 1145 pitfall trap sites in northern England and southern Scotland were used to assess the relationship between species distribution and 12 satellite-derived land cover variables at the regional scale. A number of species were strongly associated with one cover type and negatively with others. The major variation was for preferences for covers in upland or lowland parts of the region. Other distinct preferences for some species were covers such as those at the coast whilst a number of common species showed no strong preference for any cover variable. The synthesis of ground beetle species distribution and satellite-derived cover data is discussed in relation to environmental assessment and change. [source] The Yellow-necked Mouse Apodemus flavicollis in Britain: status and analysis of factors affecting distributionMAMMAL REVIEW, Issue 3-4 2001Aidan C. W. Marsh ABSTRACT A national survey of the Yellow-necked Mouse (Apodemus flavicollis) in Britain was undertaken by The Mammal Society. The live-trapping study sampled small mammal populations from 168 deciduous woodlands in autumn 1998. Within their range, Yellow-necked Mice were widespread in deciduous woodland and were more abundant than Wood Mice in 15% of the woodlands sampled. These trapping records, as well as records solicited from local recorders, record centres and individuals, supplemented the existing distribution map, confirming the general pattern, but with minor extensions to some range borders. Yellow-necked Mice were found in woodland of all ages, but were more common in woods of ancient origin than in younger woodland. Woodland size was not important in determining the presence or abundance of Yellow-necked Mice, but they were more often absent from woods more than 2 km from neighbouring substantial woodland. The presence of Yellow-necked Mice did not affect the relative abundance of Wood Mice (Apodemus sylvaticus). However, the decline in the proportion of breeding male Wood Mice at the end of the main breeding season was more marked in those woods that also contained Yellow-necked Mice. Where their ranges overlapped, Bank Voles (Clethrionomys glareolus) were less abundant where Yellow-necked Mice were also present. The distribution of the Yellow-necked Mouse was explored with respect to a number of climatic, soil and habitat variables. Maximum summer temperature was the most significant variable explaining distribution, although woodland cover variables also contributed. Soil moisture and pH, mean rainfall and winter temperature parameters did not predict Yellow-necked Mouse distribution. Low summer temperature may limit Yellow-necked Mouse distribution through its impact on tree seed production and diversity. Climatic change leading to a rise in summer temperature might encourage range expansion by Yellow-necked Mice, if their other habitat requirements are met. [source] Simulation of the mean urban heat island using 2D surface parameters: empirical modelling, verification and extensionMETEOROLOGICAL APPLICATIONS, Issue 3 2009Bernadett Balázs Abstract The spatial distribution of the annual mean urban heat island (UHI) intensity was simulated applying empirical models based on datasets from urban areas of Szeged and Debrecen, using simple and easily determinable urban surface cover variables. These two cities are situated on the Alföld (Great Hungarian Plain) and have similar topographic and climatic conditions. Temperature field measurements were carried out, Landsat satellite images were evaluated, and then one- and multiple variable models were constructed using linear regression techniques. The selected multiple-parameter models were verified using independent datasets from three urban settlements. In order to obtain some impression of the mean UHI patterns in other cities with no temperature measurements available, the better model was extended to urban areas of four other cities situated in geographical environments similar to Szeged and Debrecen. The main shortcoming of typical empirical models, namely that they are often restricted to a specific location, is overcome by the obtained model since it is not entirely site but more region specific, and valid in a large and densely populated area with several settlements. Copyright © 2009 Royal Meteorological Society [source] | ||||||||||