Karen J. Esler

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ANNA L. JACOBSEN, LIZE AGENBAG*, KAREN J. ESLER†, R. BRANDON PRATT‡, FRANK W. EWERS§ and STEPHEN D. DAVIS¶ Department of Plant Biology, Michigan State University, East Lansing, MI 48824–1312, USA, * Department of Botany and Zoology, Stellenbosch University, Private Bag X1, 7602 Matieland, South Africa, † Department of Conservation Ecology and Entomology,(More)
Namaqualand is a winter-rainfall desert of some 50 000 km2, located in north-western South Africa. For a desert ecosystem, the region is characterized by a unique selective regime, namely highly predictable annual rainfall and a moderate temperature regime throughout the year. This selective regime is responsible for the unique plant ecological features of(More)
This paper investigates of the spatial arrangement of individual plants in mapped plots in two desert communities in the winter rainfall region of South Africa. In both communities there was a very strong tendency towards clumped patterns when all plants were considered together. There was also a predominance of clumped patterns when the most abundant(More)
The control of invasive alien plants often involves the integration two or more approaches, including mechanical clearing, the application of herbicides, burning, and biological control. More than one species of invasive plant can threaten the same area, which necessitates prioritization in the allocation of scarce resources to support the control of(More)
Mediterranean-type climate regions are highly biodiverse and predicted to be particularly sensitive to climate change. Shrubs of the mediterranean-type climate region of South Africa are highly threatened, and their response to water stress has been comparatively little studied. Resistance to water stress induced xylem cavitation (P(50)) and xylem specific(More)
Nowhere is the species diversity of geophytes greater than in the five mediterranean-climate ecosystems of the world. Of these, the Cape mediterranean zone of South Africa is the most speciose. While the relative diversity and importance of geophytes of all of the other four mediterranean regions of the world drops off sharply as one moves into adjacent(More)
Selected life-history characteristics of Mesembryanthema species occurring on and off mima-like mounds (heuweltjies) were compared at Tierberg in the southern Succulent Karoo, South Africa. Seed production, the number of seeds retained in seed capsules and germination behaviour were measured in fourteen species of Mesembryanthema which were representatives(More)
The Fynbos biome in South Africa is renowned for its high plant diversity and the conservation of this area is particularly important for the region. This is especially true in the case of endangered vegetation types on the lowlands such as Sand Fynbos, of which only small fragments remain. The question is thus whether the diversity of the above-ground(More)
Invasion biology is a growing discipline with clear ecological, social and economic implications. A wide range of research effort is thus required to address the invasion problem, and literature on the topic is extensive. However, the extent to which the invasion biology research is addressing the challenges associated with management and mitigation of the(More)