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The plant communities of the Long Mynd plateau are the culmination of over 3000 years of human intervention that largely deforested the uplands, and subsequently maintained the generally treeless heath and grassland communities now extant. The capacity of these communities to respond to directional change is well known, indeed the traditional mode of heathland management, burning, depends on the regenerative capacity of the target species, generally heather (Calluna vulgaris), for its success. However, changes in post WW2 stocking practice; the loss of ponies followed by an increase in the numbers of sheep and a change to them being overwintered on the hill, led to excessive grazing and damage to the heath. This coincided with the spread over the hill by bracken (Pteridium aquilinum) and other changes in the distribution and nature of the vegetation. A sequence of vegetation surveys made by various individuals and organisations over the past 75 years or so has been analysed in an attempt to delineate spatial and temporal changes in the vegetation. This demonstrated the need for a standardised survey methodology to allow consistent monitoring. The analysis showed that bracken had been infiltrating most of the communities from its origins outside the lower limits of the Common as well as from some of the valley sides. Within the last decade, this expansion has apparently been contained in line with the current management plan for control. A survey of 730 quadrats in some 30 stands was made to characterise the variation of the vegetation on the plateau, and to relate it to some of the associated environmental factors. Classification, unconstrained ordination and ordination constrained by the abiotic environmental variables, showed that, a) the strongest trend in the vegetation distinguished water-flushed communities, b) non-wetland communities differentiate between heathland and grassland, c) this trend can be only partly be attributed to the measured abiotic environmental variables, d) the amount of pure Pteridietum [U20] is limited, although much of the heathland and grassland has bracken within it. There are indications that invasion by bracken often correlates with a loss of dominance of Calluna in favour of Deschampsia flexuosa and Vaccinium myrtillus. Difficulties in associating these trends with measured abiotic variables suggests, other factors probably management processes, are critical in driving this trend. Distribution of ‘heathland’ bryophytes was found to be associated more with the structure of their ‘host’ vascular communities rather than with abiotic factors. Finally, this investigation considers the practical implications with regard to the future encouragement of heather and the control of bracken. Cutting rather than burning appears to be the ecologically most suitable method for heather regeneration and bracken control.

The aim of this thesis was to carry out an analysis of primary school textbooks considering bryophytes and bracken, as well as to plan a biological excursion in the area of Dolský Mlýn which would include mapping the terrain. The sixth chapter contains the analysis of nine textbooks from different publishing houses. I have compared them in terms of the number of pages dedicated to bryophytes and bracken and in terms of the number of stated bryophytes and bracken representatives. I have also compared whether the textbooks are provided by workbooks, methodological guides and other material, which could variegate biology and natural history teaching. The seventh chapter characterises the location. Mapping of the terrain for the planned excursion took place in September 2012. I chose fourteen suitable sites which are were easily accessible. The eight chapter includes methodical instructions of the excursion for teachers, worklists and the key to determining types of bryophytes. The practical verification of my thesis took place in April 2013 during an excursion of seventh grade pupils from the school ZŠ a MŠ Děčín IV. Laboratory training, which represents an integral part of the excursion took place in March due to unfavorable chmate conditions. Pupils determined mosses of genus Merike according to their...

Thesis (M.A.)--Brigham Young University. Dept. of History. / Includes bibliographical references (leaves 116-118).

This study examined the psychometric properties of a new measure of attention-deficit/hyperactive disorder (ADHD) symptoms , the Boatwright-Bracken Child Attention Deficit Scale (BCADS), self- and parent-report forms. Parents and children with and without ADHD completed the BCADS to determine the reliability and validity of the BCADS . The BCADS-Child and Parent had high internal consistency reliability . The total sample parent-selfratings were moderately correlated, indicating a typical level of cross informant agreement. Results indicate that the BCADS differentiates children with ADHD from children without ADHD. Children and parents in the clinical sample reported more symptoms of ADHD than those in the comparison sample. Children with and without ADHD reported fewer symptoms of ADHD than their parents. Parents' ratings on the BCADS were moderately to highly correlated with an existing measure of ADHD. Overall, the results indicate the BCADS-Child and Parent forms are internally reliable and valid measures to use when assessing ADHD.

An understanding of the distribution of the Bracken fern (Pteridium aquilinum (L.) Kuhn) is critical for providing an appropriate management strategy. In this regard, remote sensing can play a critical role in mapping and modelling such distribution. In this study, an integrated approach using the random forest, maximum likelihood and vegetation indices was developed and tested to determine the capability of WorldView-2 multispectral eight band image in characterising the Bracken fern. Results based on the WorldView-2 were further compared to SPOT-5 multispectral (MS) image findings. The WorldView-2 (WV-2) image was spectrally resized to four traditional bands (blue, 450-510nm; green, 510-580 nm; red, 630-690 nm and NIR1, 770-895 nm) and four additional bands (coastal blue, 400-450 nm; yellow, 585-625 nm; red-edge, 705-745 nm and NIR2, 860-1040 nm) to evaluate the practicality of the spectral resolution in mapping the Bracken fern. The results from this analysis showed that the spectrally resized additional bands were more successful in general land cover mapping and characterising the Bracken fern. The result’s overall accuracy was 79.14% while the user’s and producer’s accuracies were 97.62% and 91.11% respectively. The second part of the study sought to improve the classification accuracy by applying a robust machine learning algorithm, the random forest. Since the random forest does not automatically choose the optimal bands, the backward variable elimination technique was employed to identify the optimum wavelengths in WV-2 for the identification of the Bracken fern. Respective out-of-bag (OOB) errors of 13.1% and 9.17% were achieved when the WV-2’s eight bands and optimally selected bands (n= 5) were used. These bands lie in the green (510-580nm), near-infrared1 (770-895nm), red-edge (705-745nm), near-infrared2 (860-1040nm) and the coastal blue (400-450nm) regions of the electromagnetic spectrum. These findings confirm the importance of the additional bands in vegetation analyses. The vegetation indices computed from these regions of the spectrum were superior to those in the visible region. The classification accuracy using WV-2 bands was superior to that from the commonly used SPOT 5 image. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2014.

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