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Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013 The flood of 2000 caused extensive changes within the riparian landscape of the Sabie River, Kruger National Park (KNP). Changes within the riparian landscape and the removal of vegetation resulted in considerable changes in riparian vegetation characteristics. Open patches created by the flood served as a template for the establishment of new species and the regeneration of existing species, which consequently resulted in a patch mosaic. This memorable event encouraged an investigation into the response of the Sabie River ecosystem to the memorable Large Infrequent Disturbance (LID). Riparian ecosystems are driven by varying combinations of environmental factors, such as water availability, disturbance, herbivory, fire and river morphology. This complexity depicts unique vegetation structure and assemblages of associated plant species. The lack of sufficient knowledge on the role of riparian vegetation in the health assessment of surrounding ecosystems along semi-arid rivers prompted the establishment of the Kruger Rivers Post Flood Research Program (KRPFRP). Research conducted through this monitoring program four years after the 2000 flood, revealed no significant changes in the species composition, although the location and density of many common riparian species have been changed. There was a decrease in species density across the macro channel floor (MCF) and an increase in species density across the macro channel bank (MCB). Furthermore, it was reported that the flood altered the distribution of height classes across the macro channel. In general the riparian vegetation was shorter and bushier four years post-flood. These studies furthermore illustrated that the tree to shrub ratio did not change drastically from pre-flood conditions, although a decrease in the number of shrub individuals was reported. The research presented in this dissertation was designed to further explore changes in woody species composition and structure along the Sabie River, KNP at a post flood temporal interval, i.e. between the last survey in 2004 (by the KRPFRP) and 2010. For data compatibility, the sampling and analytical approach of this study conforms to the approach followed by the KRPFRP. Data were sampled within four preselected belt-transects that form part of the larger KRPFRP. All established woody individuals were counted and measured within each contiguous 10 m x 30 m plot within each of the four belt-transects. Log transformed species composition data were analysed through the application of the Bray Curtis dissimilarity index in combination with Ward’s method of clustering. Statistical significant differences between clusters were tested through the application of the Fisher’s exact relationship test. The MIXED Procedure or PROC MIXED model was used to investigate change within the vegetation structural data. Results obtained through the various analytical methods broadly support the findings of the KRPFRP. No significant change in woody species composition could be detected between 2004 and 2010. However, a change in the density (increase and decrease) of certain species across the MCB and MCF was revealed. Species richness and density increased significantly on the MCF oppose to small changes on the MCB. A significant increase in the total number of shrubs on the MCF contributed to an overall increase in woody density for the entire study area between 2004 and 2010. Shrubs therefore remained the most dominant growth form in both sampling years. Trees decreased across the MCB although the total number of established trees remained unchanged between 2004 and 2010. Riparian vegetation structure is directly linked to species assemblages, hence the continued dominance of shrub species along the Sabie River in the KNP The Sabie River riparian landscape is therefore still characterised by short and multi-stemmed woody individuals ten years after the LID. Masters

WOS: 000288187800014 The chlorococcal chlorophyte community structure and seasonal variations in terms of species composition and abundance of dominant species in Tatli, Gici, Liman, and Cernek lakes (Samsun, Turkey) were investigated between 1996 and 2003. Species richness and diversity (Shannon-Weaver, H') were measured monthly from stations at the surface of each lake. Changes in the Chlorococcales community structure were examined with nonmetric multidimensional scaling (NMDS) ordinations. A total of 36 Chlorococcales species were identified in these lakes located in the Kizilirmak Delta. While the Chlorococcales composition was similar in Tatli, Gici, and Liman lakes, Cernek Lake showed different seasonal trends, indicating high species richness. Ankistrodesmus falcatus and Kirchneriella obesa were important in terms of their contribution to the total Chlorococcales present in Tatli, Gici, and Liman lakes, and Monoraphidium irregulare had high concentrations among the Chlorococcales in Cernek Lake. There were clear increases in the species richness of Monoraphidium and Ankistrodesmus in all lakes during winter compared with other seasons. Scientific Research Foundation of Ondokuz Mayis UniversityOndokuz Mayis University [F212] This study was supported by the Scientific Research Foundation of Ondokuz Mayis University (Project No: F212). The authors would like to thank Beyhan TAS for sharing the data from Cernek Lake and for contributions to the manuscript.

In the tropics, human disturbance continuously challenges initiatives for habitat conservation. In these regions, as economical budgets for conservation shrink, conservation planning requires precise information on when and how different kinds of disturbance may affect natural populations, but also on adequate experimental designs to monitor them. Due to their high diversity, ecological role, stable taxonomy and facilities to sample, dung beetles are used in biodiversity surveys for conservation purposes worldwide. Here we studied the short-term effects of dung beetle communities to an important and widespread ecological disturbance due to road construction in the Amazon basin. We surveyed the dung-beetle community in a spatio-temporal context, i.e. in transects located at 10, 50 and 100-m from a newly constructed, 10-m wide, paved road. The sampling periods took place 1, 3 and 6 months after the construction. During the survey, we collected 4895 specimens that belong to 69 species in 19 dung beetles genera. Six dung beetles species (Canthon aequinoctialis, C. luteicolis, Dichotomius fortestriatus, Eurysternus caribaeus, E. confusus and Onthophagus haematopus) accounted for 55% of all individuals collected. Both species diversity and abundance tended to decrease during the 6 months after the opening of the road, but not with distance from the road. Accordingly, an NMDS analysis revealed clear differences in dung beetle community composition and biomass among the three sampling periods, but not with respect to transect location. However, the number of rare species tended to increase toward the forest interior. A detailed analysis of dung beetle species among transects revealed that 5 species (Sylvicanthon bridarollii, Canthidium sp. 2, C. sp. 6, C. sp. 7 and Ontherus diabolicus) were more abundant when getting further from the road. On the contrary 6 species (Eurysternus hamaticollis, E. velutinus, E. confusus, E. caribaeus, Deltochilum oberbengeri and D. orbiculare) increased in abundance in the transect next to the road. Our study therefore confi rmed that while overall community metrics did not respond to road construction, several rare dung beetle species did, within an incredibly rapid time frame. While pattern based descriptions of dung beetle responses to anthropogenic activities are common in the literature, our fi ndings suggest that effect of roads is certainly under emphasized.

Lo studio ha avuto lo scopo di evidenziare e valutare il possibile impatto legato alla fruizione didattica che insiste nella zona più sensibile della Riserva Marina di Miramare (Trieste), la zona di marea . Sono state definite e campionate due stazioni di superficie 50*100 cm, una delle quali è stata isolata e tenuta chiusa alla fruizione, all'interno della spiaggia a sabbia e ciottoli sulla quale si svolgono le attività di educazione ambientale. I dati raccolti nell'arco di un periodo di due anni, sono stati analizzati utilizzando l'analisi della varianza (ANOVA) e i criteri dell' analisi multivariata e i risultati ottenuti hanno evidenziato che nel sito chiuso la comunità mantiene nel tempo una costanza nella macrostruttura, contrariamente al sito di fruizione didattica dove si evidenzia una maggiore variabilità.

Cover crops are a suite of non-marketable plant species grown to improve soil quality. They may have additional benefits including reduced weed pressure and enhanced habitat for beneficial arthropods, but they do not provide direct revenue. Integrating sheep grazing for cover crop termination could make the use of cover crops more economically feasible. However, if grazing shifts biological communities to assemblages of less desired species, producers are unlikely to use this method of cover crop termination. We compared weed and carabid beetle (Coleoptera:Carabidae) communities between cover crops terminated by sheep grazing and those terminated by mowing. Our study consisted of two trials of a two-phase experiment. In the first phase (cover crop phase), we seeded a four-species cover crop to enhance nutrient cycling and prevent erosion. The cover crop consisted of buckwheat (Fagopyrum esculentum), sweetclover (Melilotus officinalis), beets (Beta vulgaris), and peas (Pisum sativum). The cover crop grew to anthesis, and was terminated by either sheep grazing or mowing. In the second phase (cash crop phase), we sowed three cash crops through the previously grazed or mowed plots to assess legacy impacts of cover crop termination strategies on weed community structure. Both years, weed species richness and biomass were greater prior to than after cover crop termination, but overall weed diversity, species richness, and biomass did not differ between grazed and mowed plots. We found no difference in weed diversity, species richness, biomass, or density in the cash-crop phase between previously grazed and mowed plots. Despite temporal differences in species richness and activity–density, carabid diversity, species richness, and activity–density did not differ between grazed and mowed plots. Overall, our results suggest that grazing and mowing act as similar ecological filters of both weed and carabid beetle communities.

Trotz der Vielfalt von Einstellungsdefinitionen und - konzeptionen stellen Fragen nach der Bewertung sozialer Konzepte unbestritten die prototypischsten Operationalisierungen von Einstellungen dar: „Wie sympathisch finden Sie den Politiker X“ oder „Wie gern wurden Sie mit dieser Person zusammenarbeiten“. Die Frage nach der Organisation oder Struktur sozialer Einstellungen wurde als ein Aspekt der Untersuchung individueller Differenzen schon fruh gestellt (z.B. Eysenck, 1954; Ferguson, 1941; Kerlinger, 1984). Analog zur Untersuchung von Personlichkeitsund Temperamentsmerkmalen wird in dieser Tradition die Struktur von Einstellungen mit Hilfe von Faktorenanalysen bestimmt. Als Datenbasis dienen hierfur die Antworten einer Stichprobe von Personen auf eine Vielzahl von Einstellungsfragen. Faktoren wie „Konservatismus“ oder „Liberalismus“ konnen auf diese Weise etabliert werden. Sie erlauben es, Unterschiede zwischen Personen bezuglich einer Reihe von Einstellungen okonomisch zu beschreiben, und dienen als Pradiktoren fur die Vorhersage von Unterschieden im Verhalten (z.B. Wahlverhalten).

Background Orf is a zoonotic and epitheliotrophic contagious disease that mainly affects sheep, goats, wild ruminants, and humans with a worldwide distribution. To date, there is little information on the characterization of ORFV strains that are endemic in Mainland China. In addition, the relationship between the severity of disease and the molecular profile of ORFV strains has not been fully elucidated. Results From the recent outbreak of a sheep herd in Nongan, northeast of China, the novel orf virus (ORFV) strain NA1/11 was successfully isolated. Western blot analysis indicated that the NA1/11 strain cross reacts with monoclonal antibody A3 and infected sheep ORFV antiserum. The purified virions revealed the typical ovoid shape when observed by atomic force microscopy. To determine the genetic characteristics of the NA1/11 strain, the sequences of ORFV011 (B2L), ORFV059 (F1L), ORFV109, ORFV110 and ORFv132 (VEGF) genes were amplified and compared with reference parapoxvirus strains. Non-metric multidimensional scaling (nMDS) was performed to analyze the nucleotide similarities between different ORFV strains. Conclusions Phylogenetic analysis based on ORFV 011 nucleotide sequences showed that the NA1/11strain was closely related to Xinjiang and Gansu strains. ORFV110 and ORFV132 genes are highly variable. The results revealed that precise phylogenetic analysis might provide evidence for genetic variation and movement of circulating ORFV strains in Northeast China. In addition, nMDS analysis showed that geographic isolation and animal host are likely major factors resulting in genetic differences between ORFV strains.