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Wassenaar T.D.,Center for Monitoring Research | Henschel J.R.,Center for Monitoring Research | Pfaffenthaler M.M.,Fauna and Flora International | Mutota E.N.,Center for Monitoring Research | And 2 more authors.
Journal of Arid Environments | Year: 2013

The Namib Desert is an ancient desert on the west coast of southern Africa. The Namib has unique endemic biodiversity and scenic landscapes, with a major part contained in the Namib Naukluft Park and the adjacent Dorob National Park, together forming a major tourism attraction in Namibia. There are currently large exploration and mining developments in the central Namib, fuelled by rising global demand for uranium. Mining contributes significantly to the Namibian GDP, but through destruction of habitats and ecological processes, may cause environmental degradation and loss of ecosystem services. Additionally, Namibia stands to lose a significant part of the biological diversity that makes it unique. These direct impacts are occurring in the context of regional climatic changes that are predicted to have their own severe impacts on biodiversity. A number of tools exist to counter these impacts, among which ecological restoration is an important one. Yet the extent of the damage to ecological processes and functions of the Namib, the interactions with climate change and the mechanisms through which the impacts will occur are still not well known. There is thus a crucial need for a better understanding of these arid ecosystems and their response to disturbance, to devise better restoration techniques, and to inform decision makers about management options. This paper analyses the extent of the threats to the central Namib's ecosystems and biodiversity due to mining, identifies critical knowledge gaps for restoration, defines policy needs, and proposes a broad strategy which is intended to be a framework for research, planning and management for sustainable use of this unique desert. © 2012 Elsevier Ltd. Source

Akhtar-Schuster M.,University of Hamburg | Thomas R.J.,Longwood University | Stringer L.C.,University of Leeds | Chasek P.,International Institute for Sustainable Development | And 2 more authors.
Land Degradation and Development | Year: 2011

The need to mainstream land degradation issues into national policies and frameworks is encouraged by international mechanisms such as the United Nations Convention to Combat Desertification (UNCCD) and the Millennium Development Goals (MDGs, 2000). However, mainstreaming has faced a number of interrelated institutional, financial, legal, knowledge and policy barriers. As such, despite 15 years of existence of the UNCCD, successes in reversing and/or preventing land degradation are widely perceived to be limited. This paper highlights the nature of these barriers to mainstreaming and identifies ways in which specific limitations that hamper mainstreaming of land degradation into national, regional and international activities and policies may be overcome. It also identifies institutional infrastructures through which scientific findings may more effectively enter policy, suggesting that scientific bodies are required to strategise, coordinate and stimulate the global scientific research community to support mainstreaming and the up-scaling of efforts to combat land degradation. Such a scientific body could also stimulate national cross-sectoral and multi-stakeholder knowledge exchange. The paper then moves to the national level to examine mainstreaming processes in Namibia, a country particularly advanced in taking a more integrated approach. Although the Namibia case study shows an impressive degree of integration, there are still many lessons to be learned in order to further strengthen mainstreaming processes. These lessons form the basis of our conclusion and recommendations, which outline a potential way forward. Copyright © 2010 John Wiley & Sons, Ltd. Source

Besler H.,University of Cologne | Lancaster N.,Desert Research Institute | Bristow C.,Birkbeck, University of London | Henschel J.,Gobabeb Research and Training Center | And 4 more authors.
Geografiska Annaler, Series A: Physical Geography | Year: 2013

The dynamics of a small linear dune on the northern margin of the Namib Sand Sea have been monitored using erosion pins placed at the dune tip since 1969. GPS measurements of these pins enabled estimation of the rates of advance and lateral migration of the dune. The average rate of advance of the dune tip over the period 1969-2012 was 1.99myr-1 towards 015°. Rates of advance and lateral movement varied over the period of monitoring, with a decrease in rates of advance by a factor of 50%, but an increase in the rate of lateral movement. Changes in dune behavior appear to be related to changes in wind regime and the vegetation cover of the interdune area, as a result of increased rainfall in recent years. This study demonstrates the dynamic nature of the tip of this dune and its sensitivity to changes in winds and sand supply. © 2013 Swedish Society for Anthropology and Geography. Source

Valverde A.,University of Pretoria | Makhalanyane T.P.,University of Pretoria | Seely M.,Desert Research Foundation of Namibia | Cowan D.A.,University of Pretoria
Molecular Ecology | Year: 2015

Most ecological research on hypoliths, significant primary producers in hyperarid deserts, has focused on the diversity of individual groups of microbes (i.e. bacteria). However, microbial communities are inherently complex, and the interactions between cyanobacteria, heterotrophic bacteria, protista and metazoa are likely to be very important for ecosystem functioning. Cyanobacterial and heterotrophic bacterial communities were analysed by pyrosequencing, while metazoan and protistan communities were assessed by T-RFLP analysis. Microbial functionality was estimated using carbon substrate utilization. Cyanobacterial community composition was significant in shaping community structure and function in hypoliths. Ecological network analysis showed that most significant co-occurrences were positive, representing potential synergistic interactions. There were several highly interconnected associations (modules), and specific cyanobacteria were important in driving the modular structure of hypolithic networks. Together, our results suggest that hypolithic cyanobacteria have strong effects on higher trophic levels and ecosystem functioning. © 2015 John Wiley & Sons Ltd. Source

Stomeo F.,University of the Western Cape | Stomeo F.,Kenya International Livestock Research Institute | Valverde A.,University of the Western Cape | Valverde A.,University of Pretoria | And 7 more authors.
Extremophiles | Year: 2013

The Namib Desert is considered the oldest desert in the world and hyperarid for the last 5 million years. However, the environmental buffering provided by quartz and other translucent rocks supports extensive hypolithic microbial communities. In this study, open soil and hypolithic microbial communities have been investigated along an East-West transect characterized by an inverse fog-rainfall gradient. Multivariate analysis showed that structurally different microbial communities occur in soil and in hypolithic zones. Using variation partitioning, we found that hypolithic communities exhibited a fog-related distribution as indicated by the significant East-West clustering. Sodium content was also an important environmental factor affecting the composition of both soil and hypolithic microbial communities. Finally, although null models for patterns in microbial communities were not supported by experimental data, the amount of unexplained variation (68-97 %) suggests that stochastic processes also play a role in the assembly of such communities in the Namib Desert. © 2013 Springer Japan. Source

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