Comparing biodiversity between protected savanna and adjacent non-protected farmland in the southern Kalahari

In this study we investigated the effect of different land use options (wildlife versus livestock) on species richness of plants and reptiles in the protected Kgalagadi Transfrontier Park (KTP) versus adjacent non-protected farmland within the same savanna habitat type (Aoub dune veld) in the southern Kalahari, South Africa. Our results show that both plant and reptile species richness as well as plant cover and reptile abundance was significantly higher in the protected KTP than in the non-protected farmland. The higher proportion of shrub but lower proportions of perennial grass cover, herb cover, and herb species richness in the farmland can be explained by higher stocking rates and the differences in feeding behaviour between native wild ungulates (e.g. Antidorcas marsupialis, Oryx gazella) and livestock (mainly sheep). The reptile’s prey availability and microhabitats (perennial grass tussocks and rodent burrows) for thermoregulation and protection against predators were significantly lower in the farmland. To conclude, our results clearly show that long term effects of different land use options (wildlife in protected KTP versus extensive livestock production in the non-protected farmland) even within the same habitat type have led to significant changes in vegetation composition, availability of microhabitat structures and in the reptile community.     

Early Eocene magnetostratigraphy and tectonic evolution of the Xining Basin,NE Tibet

The Cenozoic strata of the Xining Basin, NE Tibet, have provided crucial records for understanding the tectonic and palaeo-environmental evolution of the region. Yet, the age of the lower part of the sedimentary stratigraphy and, consequently, the early tectonic evolution of the basin remain debated. Here, we present the litho- and magnetostratigraphy of various early Eocene sections throughout the Xining Basin independently constrained by the U–Pb radiometric age of a carbonate bed. Our study extends the dated stratigraphy down to 53.0 Ma (C24n.1r) and reveals highly variable accumulation rates during the early Eocene ranging from 0.5 to 8 cm/ka. This is in stark contrast to the low but stable accumulation rates (2–3 cm/ka) observed throughout the overlying Palaeogene and Neogene strata. Such a pattern of basin infill is not characteristic of flexural subsidence as previously proposed, but rather supports an extensional origin of the Xining Basin with multiple depocentres, which subsequently coalesced into a more stable and slowly subsiding basin. Whether this extension was related to the far-field effects of the subducting Pacific Plate or the India–Asia collision remains to be confirmed by future studies.     

Statistical EOF analysis of spatiotemporal glacier mass-balance variability: a case study of Mittivakkat Gletscher,SE Greenland

An Empirical Orthogonal Function (EOF) variance analysis was performed to map in detail the spatiotemporal variability in individual stake mass-balances (ba) on Mittivakkat Gletscher (MG) – in a region where at present five out of ~20.000 glaciers have mass-balance observations. The EOF analysis suggested that observed ba was summarized by two modes: EOF1 and EOF2 represented 80% (significant) and 6% (insignificant) of the explained variance, respectively. EOF1 captured a decline in ba that was uniformly distributed in space at all stakes. The decline was correlated with albedo observations and air temperature observations from nearby stations. EOF2, however, described variations in ba that were heterogeneously distributed among stakes and associated with local slope and aspect. Low elevation stakes (~<400 m a.s.l.) showed relatively negative (out of phase) correlation and higher elevated stakes relatively positive (in phase) eigenvector correlation values with EOF2. Such relatively negative and positive eigenvector correlation values were present where the constituted of exposed glacier ice or snow cover, respectively. The results from this study show how EOF analyses can provide information on spatiotemporal patterns of glacier mass-balance. Understanding such detailed variabilities in mass-balance on a Greenlandic glacier is of interest because a fifth of the Arctic contribution from glaciers and ice caps to sea-level rise originates from Greenland.     

European Observation Network: Ground - Based Support for Gamma-Ray Satellites

We present first preliminary results obtained with the European Observation Network consisting of 9 observatories in the Czech Republic, Germany and Bulgaria. We also discuss related problems such as the background of unknown variable stars and suggest a strategy for work in this area.     

Palaeomagnetism of the Proterozoic Zig-Zag Dal Basalt and the Midsommersø Dolerites, eastern North Greenland

Summary. Palaeomagnetic investigations are reported from 24 sites in the Proterozoic Zig-Zag Dal Basalt Formation and 12 sites in the Midsominersø Dolerites of eastern North Greenland. The Zig-Zag Dal Basalt is a typical tholeiitic flood basalt sequence, and dolerite intrusions in the underlying sandstones are thought to be genetically related to the basalts.
After a detailed AF demagnetization programme 19 sites in the basalts and 10 sites in the dolerites reveal one stable component of magnetization, probably of TRM and/or CRM origin residing in small single domain titano-magnetite grains. The degree of anisotropy has not affected the direction of the remanent magnetization. The maximum axis of the anisotropy ellipsoid is parallel to the flow direction of the magma, whereas the minimum axis is perpendicular to the flow plane.
Only one polarity of the geomagnetic field was found. The mean palaeomagnetic pole positions for the two rock types are not significantly different (basalt: 12.2°S, 62.8°E with A ₉₅= 3.8°; dolerites: 6.9°S, 62.0°E with A ₉₅ = 5.1°). After correction for Phanerozoic drift of Greenland the two mean poles compare closely to a relevant North American APW-curve for 1250–1350 Ma, in good agreement with Rb-Sr isochron ages of 1250 Ma obtained for the intrusives. The palaeogeographical position of Greenland was near equator with the major geographical axis orientated E-W.     

Small towns resisting urban decay through residential attractiveness. Findings from Denmark

Small towns are often considered as losing out in the current trend towards urban development. However, research from around Europe shows a great diversity of small town development, including successful development trajectories despite geographical disadvantages. Investigations into this are predominately done in the context of economic development and urban systems, but such approaches fail to explain why a number of small towns that are not centrally located near a metropolitan region are not in decay. This paper examines how the restructuring of retail and service sectors, demographic composition, residential migration, social organisation and community engagement form and affect small town (1000–5000 inhabitants) development patterns in Denmark and specific place-based endowments. The study is carried out with mixed methods, comprising a quantitative analysis of development trends, complemented by qualitative case studies in six small towns. Our findings show how favourable development paths are a combination of a positive development in population, provision of daily commodities and attractive housing, and a high number of local voluntary social organisations. Introducing the concept of ‘residential urbanism’, the paper discusses the extent to which a residentially driven urban development can compensate for the generally unfavourable regional development context.     

Urban-waterfront developments: a geographic problem in search of a model

A modified version of the economic rent model is applied to the significant urban-waterfront changes which have characterized most European and North American port cities during the twentieth century. The model is at this stage conceptual, although supported by case studies, and employs elements which are characteristic of the majority of waterfront renewal literature. The model addresses four different conditions, three of which trace the evolution which has characterized the traditional inner-city port. The first analyzes the conditions prevailing prior to the late 1950s, when most ocean cargo still used the traditional harbor. The second application of the model relates to the dynamic changes which started in the late 1950s and lasted approximately 20 years, a period in which many piers and warehouses were abandoned and destroyed. The urban-waterfront renewal efforts which have occurred in both Europe and North America are analyzed in the third phase, which emphasizes boundary changes and potential and real economic rent windfalls accruing to landowners in the path of or adjacent to proposed urban-waterfront renewal efforts. The final application of the model reviews the impact on both economic rents and land uses of improvements to the shore and nearshore marine environment.