Some recent, ongoing or future projects are listed here in short form.

Investigation into the dispersal and deposition of seed banks under conditions of progressing desertification supported by computational fluid dynamic atmospheric modeling techniques

Annethea A Muller, Environmental and Geographic Department at University of Namibia, MA (scheduled to end Apr 2010)

• In this study the focal theme will be to portray how desertification, due to climate change and land use, may affect seed bank dynamics in terms of possible changes to the dispersal and deposition within and between seed banks. Seeds, collected by ground based and elevated nets, vials and buckets, will be sorted from detritus in order to quantify rate of dispersal, rate of deposition, seed densities and viable seeds between and within microhabitats. In addition, anemometers will be used to determine wind flow characteristics of the study areas. Once the relationship between seed, wind, topography and soil characteristics for an undisturbed environment is understood, it can be applied to a disturbed environment in order to explore consequences due to desertification as well as mitigation measures for such an environment.

"Non rainfall" Atmospheric Water in Arid Ecosystem Ecology

Kudzai Farai Kaseke, University of Stellenbosch, MSc in Conservation Ecology (2008)

• "Non rainfall" atmospheric water (dew, fog & direct water vapor adsorption) are an important source of water for arid ecosystem functioning. Farai's project aims to quantify and differentiate the input from the 3 processes along a transect on the South West Coast of Africa (Namibia to South Africa), to determine the influence of soil properties on this input and the effect of this water on soil respiration, which is an indicator of ecosystem activity. "Non rainfall" atmospheric water plays a crucial role in ecological processes and supplies water to the various organisms of these ecosystems. The influence of this water is greatest in the upper soil profile because of the small amounts deposited and its leaching capacity. The absolute amounts of water inputted by these 3 processes into the soil are often unknown because of instrumentation constraints. At best, the measurments give a proxy of these amounts due to differing surface characteristics to the receiving soil surface. This leads to over and under estimation of this input to soil and conclusions drawn from this data is therefore not accurate. This project will employ the use of microlysimeters, a direct method of measuring input into the soil. Potential applications of this project include combating desertification, dryland agriculture and rehabilitation of semi-arid areas where water scarcity is a limiting factor to productivity.

Isotopes, Fog and Dust in the Namib

Keir Soderberg, University of Viriginia, Environmental Sciences (Ongoing Research, Status quo: 8 March 2007)

• Many interesting research questions remain regarding the role and fate of fog in the Namib ecosystems. As an Environmental Sciences PhD student with the University of Virginia, Keir will be using this year to look into some of these questions using stable isotope geochemistry of fog, aerosols, soil and vegetation. What percentage of deposited fog becomes viable for use in the ecosystem? How do marine and terrestrial aerosols affect fog occurrence and composition? What role does fog play in nutrient cycling?

Water sourcing by riparian tree species in ephemeral rivers

Klaudia Schachtschneider, Botany Department of the University of Cape Town PhD (Scheduled to end in March 2008)

• The aim of Klaudia’s PhD is to gain a better understanding of the interactions between water sources and riparian tree species, working in the densely vegetated parts of the Kuiseb River around Gobabeb and Swartbank. It is anticipated that some tree species will change their distribution, physiological structure and/or appearance when faced with reduced water availability. Such tree responses can be used as bioindicators for determining ephemeral ecosystem health. Klaudia works on Faidherbia albida (Ana tree), Acacia erioloba (Camelthorn) and Tamarix usneoides (Tamarisk), measuring their growth rate, water stress, transpiration rates and foliage cover over a period of two years.

Regeneration and utilization of Faidherbia albida and Acacia erioloba along ephemeral rivers of Namibia

Petra Moser, University of Bonn (2006)

• In this study, the regeneration processes of the two tree species and their utilisation by local resource users was studied in the ephemeral rivers Kuiseb, Omaruru and Ugab. Germination of seeds ingested by animals and seedling emergence from different depth was tested, as well as seedling root growth, seedling survival, fitness and annual growth of juveniles, tree growth locations and tree utilisation by farmers. This study shows that regeneration of the two fodder trees Faidherbia albida and Acacia erioloba along ephemeral rivers in Namibia depends on rare surface floods of high magnitude and is threatened by increasing land-use intensity. A loss of the two tree species would limit the ability of the local resource users to derive their livelihoods form subsistence livestock farming.

Social organisation of the black backed jackal Canis mesomelas in a high density population on the desert coast of Namibia.

Nicky Jenner, Institute of Zoology, Zoological Society of London, U. K. (2006)

• This study focused on a black backed jackal population in the Cape Cross Seal Reserve and West Coast Recreation Area on the desert coast of Namibia. A large Cape fur seal colony supports populations of black-backed jackal and brown hyaena. In this study behavioural observations were used (observations conducted during the breeding season), as well as molecular (microsatellite analysis of faecal and tissue DNA) and spatial (GPS tracking and GIS) techniques to investigate the social organization of this high density black backed jackal. In particular the social and genetic mating system was investigated and the adaptive nature of helping behaviour for breeders and their offspring.

Nocturnal long-distance navigation in the Dancing White Lady Spider

Thomas Nørgaard PhD (2006)

• When searching for females the adult males of the Dancing White Lady Spider are able to wander long distances across the seemingly featureless dunes in the Namib Desert. Nearly every journey the spiders make on the surface ends with them returning to their burrows. Theoretically, such a navigational feat is only possible if the spiders employ external cues in some kind of navigational mechanism. The purpose of this study was to identify possible external cues used by the male spiders and to zero in on the underlying navigational mechanisms and strategies of these arachnids. The study shows that the direction of gravity, the sun, the moon, polarized skylight, olfaction, and vibrational beacons do not provide external cues used by the spiders. Surprising as it is, for such an extremely nocturnal spider, visual navigation based on landmarks (possibly in combination with a still unresolved path integration system) is the most likely mechanism employed by L. arenicola during its long-distance journeys. Future research should pursue these lines of reasoning and consider experimental paradigms, in which the positions of artificial local landmarks are manipulated experimentally.