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The hump-back relationship between species diversity and productivity predicts highest species richness at intermediate levels of biomass, and low species numbers in least and most productive habitats. Sodic patches of semi-arid savannas are considered ‘nutrient hotspots’ by producing high-quality forage. The impact of biomass reduction (due to overgrazing) and accumulation (in the absence of herbivores) on herbaceous species richness and diversity is still unknown for these hotspots. We tested the relationship between biomass and herbaceous species richness/diversity in savanna sodic sites across varying biomass levels obtained through different herbivore exclosures. LOWESS and quadratic regression analyses revealed a unimodal species richness/diversity–biomass relationship for biomass

It is impressive when a writer succeeds in synthesizing vast, complex literatures from a wide range of scientific disciplines and pens an engrossing and fluid best seller that does justice to the s...

The distinctiveness of Maputaland Woody Grassland lies within its richness of geoxylic suffrutices and herbaceous flora. Since it is well documented in the literature and easy to distinguish from other grassland types, it was possible to confirm a locality of this unique vegetation unit west of Richards Bay, where it probably forms the southernmost outlier population of this vegetation unit in the Indian Ocean Coastal Belt Biome. Phytosociological data obtained from the study area were analysed to identify plant communities and subsequent mapping units. Floristic gradients obtained through ordination techniques revealed the relationship that exists between the Woody Grassland of the study area and the Maputaland Woody Grassland of Sileza Nature Reserve. This confirms the occurrence of Maputaland Woody Grassland at Richards Bay. Two of the plant communities identified from the Richards Bay site are distinctively different, despite previously being lumped together by different authorities as either Kwambonambi Grassland or Maputaland Woody Grassland.

Very little is known about the relations between aloes and soil metals, despite evidence that aloes often form dense populations on metalliferous soils. This study targeted eight rock outcrops where aloes dominated the vegetation to determine whether these succulents have a preference for soils rich in heavy metals and whether they accumulate any of these metals in their leaf tissue. Soil analyses suggested that densely populated rock outcrops are rarely characterised by high concentrations of heavy metals. Analyses of leaf material revealed no metal hyperaccumulators, with most species acting as excluders of most metals. The only metals to be reflected in leaf material to some degree across populations were copper (mean of 4 µg g-1), iron (mean of 208 µg g-1), manganese (mean of 342 µg g-1) and zinc (mean of 31 µg g-1)(all values are based on leaf dry weight). Aloe greatheadii plants from the ultramafic-peralkaline Koedoesfontein Complex in the Vredefort Dome contained the highest concentrations of Mn (558 µg g-1) and were subjected to further sampling across four geological substrates to determine the limits of its accumulation ability (mean of 855 µg g-1 on wehrlite). This aloe was found to be non-hyperaccumulating, but tolerant to elevated Mn concentrations in its tissue. The uptake of Mn from the soil was not so much influenced by soil available Mn, but rather by decreasing pH, and increasing electric conductivity and soil potassium.

Giardia lamblia is the most common human parasite with a worldwide distribution and fecal-oral way of transmission. Diagnostic procedures include stool examination and gastroduodenoscopy with biopsy or secret aspiration. In most cases histology reveals a dense accumulation of the parasites on the surface of the duodenal mucosa with no or only slight inflammation. In rare cases, a dense inflammatory infiltrate with severe mucosal atrophy and increased count of intraepithelial lymphocytes may be seen. If in such cases the amount of parasites is low, the histological picture may mimic celiac disease. The two presented cases demonstrate the close morphological relationship and show the importance of considering giardiasis in the differential diagnosis in patients with suspected celiac disease.

The Primary Math Assessment (PMA) tool is increasingly being used in multiple districts in a northwestern state. The PMA provides both screening and diagnostic information in six domains to assess mathematical proficiency in young students in their early educational years. A previous study using multidimensional Rasch analyses found support for the PMA’s six-dimensional theoretical framework, and that the PMA is a reliable mathematics assessment for early grades. This study extended the examination of a Rasch model, implementing exploratory and confirmatory factor analysis, Item Response Theory, and Differential Item Functioning analyses. In doing so, this study found an IRT 2-PL model to fit best with these data and provided ways to improve the accuracy of measuring mathematical proficiency in early grades.

The advent of anti-TNF alpha antibodies has clearly improved the outcome of patients with Crohn's disease. With adalimumab, the first fully human, monoclonal anti-TNF alpha antibody, which can be administered subcutaneously by means of a pen, became available in 2007. In Europe adalimumab is approved for the treatment of severe, active Crohn's disease, in patients who have not responded despite a full and adequate course of therapy with a corticosteroid and/or an immunosuppressant; or who are intolerant to or have medical contraindications for such therapies. Adalimumab is clinically efficacious both in patients with Crohn's disease naive to previous exposure to anti-TNF alpha antibodies and in those previously exposed with a rapid onset of action and a confirmed maintenance performance over 3 years. A reduction in the rate of hospitalisation and an improvement of health-related quality of life are associated with this treatment. The safety profile of adalimumab is comparable to those of other TNF alpha inhibitors. Due to low immunogenicity, allergic reactions are rare. A careful screening of patients before and during treatment with adalimumab is of key importance. The presented therapy guidelines based on existing evidence are aimed to assist in the efficient and safe use of adalimumab in the treatment of Crohn's disease.

The need to conduct research on the impact of elephant on the environment prompted the construction of exclosures along two of the most important rivers in the Kruger National Park. Scientific research on these exclosures along the Sabie and Letaba rivers addresses how patterns of spatial and temporal heterogeneity of the riparian zone are affected by fire, flood and herbivory. To further assist this research programme, a vegetation survey was conducted at the Nkhuhlu exclosure site along the Sabie River to classify and map the vegetation of the area. This will provide baseline data to assess future changes in vegetation and floristic patterns due to small-scale environmental factors created by the presence/absence of herbivory and fire. Phytosociological data were analysed to identify plant communities and subsequent mapping units. Five plant communities, ten sub-communities and four variants were recognised and described in relation to prevailing soil forms. Differences in species richness, diversity and community structure of the plant communities are clearly articulated. http://www.scielo.org.za/scielo.php?pid=S0075-64582008000100015&script=sci_arttext http://www.koedoe.co.za/index.php/koedoe/article/download/138/738

The rattan flora of Central Sulawesi is abundant, species rich and patchily distributed in lowland and montane forests. I recorded the abundance and distribution of rattan on five randomly established 10 m × 1000 m transects between 830 and 1330 m elevation and associated changes in forest canopy heights, photosynthetically active radiation (PAR) and soil characteristics. Rattans were observed at all sites and elevations (100% of 10 m × 10 m sample plots in the transects contained rattan), but exhibited the greatest diversity (species richness) between 1180 and 1280 m elevation. Overall (all species and elevations), there was an average of 314 mature rattan genets per hectare. The two most prominent rattans in terms of size, abundance and distribution, Calamus zollingeri and Daemonorops robusta , averaged 62 and 40 genets/ha overall, respectively. Several other rattans, including C. leiocaulis , C. leptostachys, and C. ornatus occurred on all transects and all elevations. In contrast, C. didymocarpus , C. minahassae , C. symphysipus and Korthalsia celebica were patchily distributed, and C. didymocarpus and C. sp. (‘kalaka’) were restricted to higher elevations. Resident cane collectors differentiate C. zollingeri and D. robusta into low and high elevation forms on the basis of morphological and growth characteristics, but this distinction is not discernable in sterile specimens. Based on local classification, lowland forms of C. zollingeri and D. robusta were replaced by high elevation forms over less than 200 m vertical elevation which corresponds to the transition from upper lowland to montane forests. The mean canopy height of upper lowland forest between 900 and 1000 m was significantly greater than that of montane forests between 1100 and 1300 m (30.0 and 21.2 m, respectively). Soils in upper lowland forests had significantly higher concentrations of NO 3 and P, significantly lower organic matter levels and higher pH than montane soils in both O and A/E soil horizons. PAR levels did not vary significantly by forest type. Most large diameter rattans are marketed under a single trade name and cannot be distinguished by cane characteristics. These findings have significance for biodiversity conservation and management because rattan harvesting is widespread and unmanaged, and the Sulawesi rattan flora remains poorly known taxonomically and ecologically.

Rattan, Old World climbing palm, is an extremely valuable nontimber forest product whose canes are gathered for both market and nonmarket uses. I evaluated the effects of harvesting commercial rattan, Calamus zollingeri Becc., on genet survival and ramet demography in two primary forest sites near Lore Lindu National Park in Sulawesi, Indonesia. I monitored 168 permanently marked C. zollingeri genets for 4 years and surveyed random transects for C. zollingeri genet and ramet populations and evidence of cane harvesting in 1996 and 2000. Cane harvesting had no significant effect on genet survival or mean ramet densities. However, current cane extraction rates significantly reduced mean cane lengths and total available cane throughout the area during the study period. Based on observed genet and ramet populations and average cane growth rates of 1.4 m/year, the sustained-yield harvesting potential of C. zollingeri is approximately 101 m and 56 m/ha/year in the two study sites. Although C. zollingeri exhibits life-history traits well suited to sustained-yield harvesting, including production of multiple canes, cane resprouting following harvest, rapid cane growth, and widespread abundance below 1100 m, current harvest rates exceed growth and yield, and supplies of cane are being depleted. Rattan harvesting is widespread in Lore Lindu National Park. Approximately 18% of the park (42,000 ha) is likely subject to intensive and unsustainable extraction of C. zollingeri. Resumen: El ratan, palma trepadora del Viejo Mundo, es un producto forestal no maderable extremadamente valioso cuyas canas son colectadas tanto para usos de mercado como no mercado. Evalue los efectos de la cosecha del ratan comercial, Calamus zollingeri Becc., sobre la supervivencia de genet y demografia de ramulas en dos sitios de bosque primario cerca del Parque Nacional Lore Lindu en Sulawesi, Indonesia. Durante 4 anos monitoree 168 genets de C. zollingeri marcados permanentemente y revise transectos aleatorios en busca de poblaciones de genet y ramulas de C. zollingeri, asi como evidencia de cosecha de canas en 1996 y 2000. La cosecha de canas no tuvo efecto significativo sobre la supervivencia de genets ni las densidades promedio de ramulas. Sin embargo, las tasas de extraccion de cana actuales redujeron significativamente la longitud promedio de las canas y la disponibilidad total de canas en toda el area durante el periodo de estudio. Con base en poblaciones observadas de genets y ramulas y las tasas promedio de crecimiento de canas de 1.4 m/ano, el potencial de cosecha de produccion sostenida de C. zollingeri es de aproximadamente 101m y 56m/ha/ano en los dos sitios estudiados. Aunque C. zollingeri exhibe caracteristicas adecuadas para cosechas de produccion sostenida, incluyendo la produccion de canas multiples, rebrote de canas despues de la cosecha, crecimiento rapido de canas y amplia abundancia debajo de los 1100 m, las tasas de cosecha actuales exceden el crecimiento y produccion, y las reservas de cana se estan agotando. La cosecha de ratan es extensiva en el Parque Nacional Lore Lindu. Es probable que aproximadamente el 18% del parque (42,000 ha) este sujeto a la extraccion intensiva y no sostenible de C. zollingeri.

The biological diversity in traditional agroecosystems and potential diversity loss associated with land use change in upland Crete was investigated. Using transects, plots and point count sampling...

A hierarchical classification, description, and ecological and floristic interpretations are presented on the vegetation types of the ultramafic rock habitats of the Sekhukhuneland Centre of Plant Endemism. Relevés were compiled in 100 stratified random plots. A TWINSPAN classification, refined by Braun-Blanquet procedures, revealed 17 plant communities, which are classified into 13 associations belonging to four proposed alliances. Many new syntaxa are ecologically interpreted and described. For each syntaxon, the species richness, endemism and conservation status was determined. Much of the plant community distribution can be ascribed to specific habitat preference. The floristic and habitat information, proposed classification, general description and vegetation key are provided to aid future identification of conservation areas, land use planning and research. An ordination (DECORANA) based on floristic data confirmed potential relationships that could exist between the plant communities and associated habitats and environmental gradients.

The reasons why upland farmers on the Indonesian island of Sulawesi are engaged in a cacao boom and its long term implications are addressed in the context of protected area management regulations, and political and economic conditions in Post-Suharto, Indonesia. In the remote case study village of Moa in Central Sulawesi, we found that while few households cultivated cacao in the early 1990s, all had planted cacao by 2000. Furthermore, the vast majority cultivate cacao in former food-crop focused swidden fields under full-sun conditions. Farmers cultivate cacao to establish property rights in light of a land shortage driven in part by the prohibition of farming and forest product collecting in a nearby national park, and to secure a future source of income, a concern that has been exacerbated by Indonesia's economic crisis. However, conversion of swidden fields to sun-grown cacao constrains future food production opportunities, increases susceptibility to drought stress and potential soil nutrient and organic matter losses, and increases household dependence on a commodity that is subject to extreme price volatility. These factors raise significant concerns for local food security and agricultural sustainability.

Cutting small trees to float bundles of rattan cane to market is widespread in Indonesia and is purported to adversely affect primary forests and biodiversity conservation. I monitored rattan cane harvesting, tree species used as floater logs, and the locations and volume of floater log cutting in two forest villages adjacent to Lore Lindu National Park in Central Sulawesi, Indonesia for two years. During this period, an average of 135 and 100 tons of commercial rattan cane, primarily Calamus zollingeri, was harvested annually from the two villages, respectively. Floating cane to market required approximately 2350 and 1667 logs (each 3 m in length and 15-20 cm in diameter) or about 1175 and 834 trees annually in the two villages. Eight tree species were regularly used as floater logs and all were light-weight, fast-growing, pioneer species. Floater logs were harvested from fallowed shifting cultivation fields and naturally disturbed riparian flood plains. Over the two year study period, there was little floater log cutting in primary forests either inside or outside of the national park. The use of early successional tree species to float rattan to market does not appear to adversely affect primary forests or protected area management in this region.

Hepatic glycogen stores have long been known to decrease with starvation, trauma, acute stress, and shock. In this study, hepatic tissue was examined in 122 decedents ranging in age from 1 to 88 years who died of a variety of causes. Hepatic tissue was stained for glycogen/carbohydrates using the Best's carmine and/or period acid-Schiff (PAS)-alcian blue methods in 121 cases. The liver samples were evaluated for amount of staining, staining around hepatic injuries (if present), and presence of histologic abnormalities. Prominence of staining was decreased with increasing survival times after injury (P=.0001) and increasing postmortem interval. Staining along the edges of hepatic injuries was decreased in antemortem injuries but not in postmortem-induced injuries (P

The abundance, distribution and growth rates of the economically-important climbing palm, Desmoncus orthacanthos Mart., was investigated in response to cane harvesting, light and edaphic conditions in five forest sites in Belize. Desmoncus orthacanthos genet (i.e. entire plant) and ramet (i.e. individual cane or shoot) populations were abundant throughout Belize, ranging from 40 to 232 genets ha −1 and 72 to 532 ramets ha −1 in the five forest sites. Median genet and ramet populations and ramet lengths were significantly greater in high than low-light environments and in freely versus poorly drained sites based on Mann–Whitney U -tests. Similarly, the median number of new ramets produced and ramet growth were significantly greater on plants growing in high-light than low-light conditions and on plants in which ramets had been harvested versus unharvested controls 24 months after ramet harvesting. Desmoncus orthacanthos abundance, distribution and growth characteristics are typical of a wide-ranging generalist species.

This study investigated the intercropping of rattan, an important non-timber forest product, in coffee and cacao agroforests in Sulawesi, Indonesia. The viability of producing seedlings from seeds and vegetative cuttings with the large-diameter rattan, Calamus zollingeri Beccari, and initial seedling survival, growth and response to light and soil drainage were investigated in village nurseries and perennial farms. Over 96% of seeds and 61% of vegetative cuttings were raised to transplanting size (25 cm with two to three leaves) over 20 months. One hundred C. zollingeri seedlings produced from cuttings were transplanted into each of three coffee or cacao farms and one primary forest site and exhibited an overall survival rate of 96%, 12.7 cm of height growth and the production of 0.8 new leaves per plant after eight months. No significant differences were observed between the four sites with respect to seedling survival, growth, or leaf production and no significant differences were found between seedling survival, growth or leaf production and light intensity (based on multiple PAR measurements). However, poorly drained sites exhibited significantly reduced C. zollingeri seedling survival and growth. The cultivation of C. zollingeri rattan in coffee and cacao agroforests represents a potential means of intensifying and diversifying perennial cash crop farming systems.

Constraints on the proximity of the carboxyl carbons of the Asp-85 and Asp-212 side chains to the 14-carbon of the retinal chromophore have been established for the bR(555), bR(568), and M(412) states of bacteriorhodopsin (bR) using solid-state NMR spectroscopy. These distances were examined via (13)C-(13)C magnetization exchange, which was observed in two-dimensional RF-driven recoupling (RFDR) and spin diffusion experiments. A comparison of relative RFDR cross-peak intensities with simulations of the NMR experiments yields distance measurements of 4.4 +/- 0.6 and 4.8 +/- 1.0 A for the [4-(13)C]Asp-212 to [14-(13)C]retinal distances in bR(568) and M(412), respectively. The spin diffusion data are consistent with these results and indicate that the Asp-212 to 14-C-retinal distance increases by 16 +/- 10% upon conversion to the M-state. The absence of cross-peaks from [14-(13)C]retinal to [4-(13)C]Asp-85 in all states and between any [4-(13)C]Asp residue and [14-(13)C]retinal in bR(555) indicates that these distances exceed 6.0 A. For bR(568), the NMR distance constraints are in agreement with the results from recent diffraction studies on intact membranes, while for the M state the NMR results agree with theoretical simulations employing two bound waters in the region of the Asp-85 and Asp-212 residues. The structural information provided by NMR should prove useful for refining the current understanding of the role of aspartic acid residues in the proton-pumping mechanism of bR.

Several sources of errors leading to distortions in time-resolved step-scan Fourier transform infrared (FT-IR) measurements are described, and their effect on difference spectra and time traces is discussed. Fluctuations of the movable interferometer mirror as well as interference of the power line frequency are shown to be able to cause oscillations in the time traces of absorbance changes obtained by step-scan measurements. It is demonstrated that absorbance changes of the sample and thermal IR signals due to heating of the sample by laser excitation both contribute to the IR intensity changes at a fixed sampling position. Therefore, intensity variations of the laser pulses used to drive the sample reaction can cause considerable fluctuations of the time-dependent IR signals and, thereby, introduce multiplicative noise into the difference spectra. Means to correct these errors are proposed for some cases.

The aim of this study was to investigate the effects of the substitution of plowing with harrowing-twice in a 3-yr crop rotation-on persistence and distribution of a persistent herbidde such as trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) to rate these two tillage systems for their environmental impact (e.g., regarding potential ground water contamination with pesticides). Therefore, studies have been performed in Germany at two sites, a clayey silt in Reinshof and a loamy sand in Eickhorst. The herbidde was applied to oilseed rape (Brassica napus L. var. napus), followed in consecutive years by applications to wheat (Triticum aestivum L.) or to wheat followed by rye (Secale cereale L.). The disappearance time of 50% of the initial concentration (DT-50 value) decreased from >300 dafter preplant incorporation of trifluralin to

The implementation of a sample changing wheel in combination with a step-scan FTIR spectrometer is described. This device allows collecting and averaging time-resolved data of ten samples, which can be placed successively into the infrared beam. The high time-resolution of the step-scan technique can be retained to monitor the fast kinetics of systems with slow reaction cycles. Averaging the signals of several samples instead of signals of only one sample allows collecting the data with a repetition rate larger than what would be allowed by the time constant of the reaction cycle. Thus, instrumental instabilities due to a very long measuring time are avoided. It is demonstrated that, if at each mirror position the signals of the same samples are averaged, no multiplicative noise is introduced into the spectra. Results on the application of our method to the photocycle of the Asp96→Asn mutant of bacteriorhodopsin, which is slowed down by a factor of more than hundred compared to the native protein, are presented.

The D96N mutant of bacteriorhodopsin has often been taken as a model system to study the M intermediate of the wild type photocycle due to the long life time of the corresponding intermediate of the mutant. Using time-resolved step-scan FTIR spectroscopy in combination with a sample changing wheel we investigated the photocycle of the mutant with microsecond time resolution. Already after several microseconds an intermediate similar to the MN state is observed, which contrasts with the M state of the wild type protein. At reduced hydration M and N intermediates similar to those of wild type BR can be detected. These results have a bearing on the interpretation of the photocycle of this mutant. A mechanism is suggested for the fast rise of MN which provides some insight into the molecular events involved in triggering the opening of the cytosolic channel also of the wild type protein.

This study documents the abundance, distribution and knowledge of medicinal plant species in a Ransa Dayak village and adjoining forest in West Kalimantan, Indonesia. Over 250 medicinal plant species from 165 genera and 75 families are utilized by the local healer. Late successional, primary and river bench forests contained the highest diversity of locally-utilized medicinal species and the greatest number of species restricted to a single forest type for which alternative species or remedies were unavailable. Epiphytes and trees restricted to primary forests are particularly important sources for plants used to treat unusual ailments. A 100% survey of village residents 15 years of age and older (N = 32) revealed that people older than 25 years of age, and older females in particular, possessed greater knowledge of medicinal plants and their uses than younger people and males. All residents, except the male healer, were more knowledgeable about medicinal plants found in early successional forests than those of primary forests. Commercial logging and the loss of traditional knowledge through acculturation pose twin challenges to the persistence of traditional medicinal plant use in this Ransa village and throughout much of Kalimantan.

Purpose: To provide a method for calculating the transmission of any broad photon beam with a known energy spectrum in the range of 20-1090 keV, through concrete and lead, based on the superposition of corresponding monoenergetic data obtained from Monte Carlo simulation. Methods: MCNP5 was used to calculate broad photon beam transmission data through varying thickness of lead and concrete, for monoenergetic point sources of energy in the range pertinent to brachytherapy (20-1090 keV, in 10 keV intervals). The three parameter empirical model introduced byArcher et al. ["Diagnostic x-ray shielding design based on an empirical model of photon attenuation," Health Phys. 44, © 2014 American Association of Physicists in Medicine. © 2014 Am. Assoc. Phys. Med.

The transition from the Neoproterozoic Nemakit-Daldynian 1 Krol-E dolomite to the Tommotian Lower Tal phosphorite-chert–black shale sequence denotes a period of drastic change in the depositional environment and the chemical milieu of the sedimentation basin. These changes are reflected by a marked negative excursion of carbon isotopes, phosphorus enrichment, trace-metal content, high organic carbon burial and notably the first appearance of prolific small shelly fauna and burrowing organisms. Recent studies have documented these changes along several stratigraphic profiles in the Mussoorie Hills of the Garhwal Himalaya for which a single profile from the Durmala phosphorite mine provides a key section discussed here.

The effects of the management of straw, nitrogen fertilization, and application rates on the dissipation of metsulfuron-methyl, methabenzthiazuron, and trifluralin were investigated in a 3-year field crop rotation study, complemented with laboratory studies. The dehydrogenase activity in soil was measured as an indicator of the soil microflora. The effects were specific for the herbicides investigated. The amendment of straw accelerated the dissipation of trifluralin and methabenzthiazuron. Furthermore, the movement of trifluralin, but not methabenzthiazuron, in the top 30 cm of the soil was reduced. Nitrogen fertilization and high application rates significantly decreased only the dissipation of methabenzthiazuron in the laboratory. Dehydrogenase activity in soil was influenced mainly by the amendment of straw. There was no evidence for cumulative effects on herbicide dissipation due to crop management within the crop rotation. Keywords: Herbicides; degradation; straw incorporation; nitrogen fertilizatio...

Understanding relationships between large herbivores and plant species diversity in dynamic riparian zones is critical to biodiversity conservation. The Nkuhlu exclosures in the Kruger National Park (KNP) provided opportunity to investigate spatial heterogeneity patterns within riparian zones, as well as how these patterns are affected by fire and herbivory. A monitoring project was initiated to answer questions about the dynamics of the herbaceous layer and was aimed at determining, (1) whether there exists meaningful variance in herbaceous plant species richness and diversity across different treatments in the ecologically sensitive sodic zone and (2) whether an increase in herbaceous biomass, an artefact of herbivory and fire exclusion, suppresses herbaceous plant species diversity and richness. Herbaceous vegetation was sampled in two 1 m2 circular sub-plots in the eastern and western corners of 81 fixed plots. The biomass of each plot was estimated with a disc pasture meter (DPM) diagonally with the plot. DPM-readings were converted to kg/ha, according to the latest conversions for the Lowveld Savanna. Species richness and biomass showed significant variance across treatments, whereas no significant variation in herbaceous species diversity was perceived. Combined treatment of fire absence and herbivore presence contributed to higher forb species richness in the sodic zone. Biomass is significantly higher in fully fenced areas where herbivores are excluded, as opposed to the open and partially fenced areas. Although no significant variation was recorded for diversity across treatments, lowest diversity was recorded in the absence of all herbivores, especially in combination with fire treatment. Therefore herbivores are essential in sustaining herbaceous plant species richness in the sodic zone, whilst no significant results were found with regard to their effect on species diversity. Although statistically non-significant, fire seems to suppress species richness.Conservation implications: This study could be used as framework to advance and develop science-based management strategies for, at least, the sodic zones of the KNP. Research in these exclosures will create better understanding of these landscapes, benefit ecosystem conservation planning of national parks and also provide valuable long-term information on key ecological processes.

Calamus exilis and C. zollingeri are coppicing, clustering rattans that possess characteristics favorable to sustained‐yield cane harvesting in protected areas, including high population densities, year‐round cane availability, minimal adverse effects on other species when harvested, well‐developed trade networks, and strong market demand. Cane resprout and growth rate studies suggest that C. exilis can be repeatedly harvested at four year intervals; a longer, but as yet undetermined interval would be required for repeated C. zollingeri harvesting. Although ecological and economic aspects of C. exilis and C. zollingeri appear promising, sustainable harvesting by local people faces significant social and political constraints, including ill‐defined resource access and tenure arrangements, the absence of local village management organizations and harvesting guidelines, and weak political and economic power of rattan collectors and villages vis a vis outside commercial interests.

Reseach was done on the Sodics of the Nkuhlu long-term monitoring exclosures.Variation in different plant characteristics were analised across different treatments over time. No significant variation in morphological types could be detected.

Die groot vloede wat in die jaar 2000 in die Kruger Nasionale Park plaasgevind het, het die rivieroewerplantegroei versteur. Dit het die geleentheid gebied om heinings op te rig langs die Sabierivier om herbivore uit sekere gebiede uit te sluit en sodoende die herstel van die rivieroewerekosisteme te monitor.

Die groot vloede wat in die jaar 2000 in die Kruger Nasionale Park plaasgevind het, het dierivieroewerplantegroei versteur. Dit het die geleentheid gebied om heinings op te rig langsdie Sabierivier om herbivore uit sekere gebiede uit te sluit en sodoende die herstel van die rivieroewerekosisteme te monitor.

Savanna ekosisteme in Suid-Afrika word gekenmerk deur heterogeniteit op verskeie skale