Effect of fire frequency on the recovery of soil invertebrate communities in semi-arid savanna biome of the Eastern Cape, South Africa
- Authors: Madikana, Ayabulela https://orcid.org/0000-0002-9119-4650
- Date: 2021-04
- Subjects: Soil invertebrates , Fire ecology , Arid regions
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22831 , vital:52946
- Description: Fires are common in South African savanna habitats, which can disrupt the dynamics of entire invertebrate populations, endangering biodiversity and the environment. The aim of this study was to look at how fire frequency affected invertebrate population dynamics and biodiversity in a 41-year-old fire experiment at the University of Fort Hare research farm in Alice. The experiment had six different levels of burning frequency: no-burn (K), annual burn (B1), biannual burn (B2), triennial burn (B3), quadrennial burn (B4), and sexennial burn (B6). The experimental plots were replicated two times in a randomized complete block design and have been continuously retained since 1980. A ground yellow mustard solution was used to collect earthworms, which were then identified by an earthworm taxonomist. Pitfall traps were used to collect ants and other insects, which were then identified under a microscope. In total, three soil samples were collected from each plot to assess selected soil nutrients, moisture, and pH. The Shannon diversity index, richness, and population of earthworms, ants, and other insects were calculated, and a one-way ANOVA analysis was done to check if the treatments differed significantly. A correlations study was used to look for any influence connected to soil parameters, including the Shannon diversity index, species richness, and density of soil invertebrates. According to our findings, the measured parameters did not show any significant differences in the measured parameters between the different frequency levels. All the plots had two species of earthworm , Proandricus timmianus and Proandricus beddardi except the biennial burn plot, which had all three, the afore mentioned species and one other unidentified species, Proandricus sp. The triennial burn treatment slightly enhanced the insect diversity, richness, and evenness of ant species difference while the diversity, evenness, and richness were lowest in the sexennial burn plot. However, there was no signif difference in population. After B4, the no burn plot had the second largest diversity and species richness, and the third highest species evenness and had a 100 percent species similarity index. The ants were evenly distributed in the no burn plot compared to the other plots, with K having a lower density than the other plots except for B4, K being slightly more diverse than B6, and B1 with a slightly lower diversity than the other plots, and it being the third species rich plot after B2 and B3, followed by the rest of the plots. This study implied that fire frequency has an insignificant impact on invertebrates’ communities in Savanna biomes words.icant , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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- Date Issued: 2021-04
Geochemical exploration in arid and semi-arid environments
- Authors: Van Berkel, Ferdinand
- Date: 1983 , 2013-04-02
- Subjects: Geochemical prospecting , Arid regions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4920 , http://hdl.handle.net/10962/d1004389 , Geochemical prospecting , Arid regions
- Description: Anomalous element distributions within the regolith result from chemical adjustments of the earth's surface to prevailing climatic conditions. Because of the lack of moisture in the arid environment, chemical equilibrium related to paleoclimates is largely maintained. Mechanical or clastic dispersion dominates arid weathering and hence the exploration approach is largely dictated by the degree of preservation of the paleoregolith. Arid environment geochemists thus have to contend with surface materials ranging from laterite and calcrete in areas where the imprint of aridity is minimal, to more conventional sample media such as bedrock, stream sediment and lithic soils in actively dissecting areas. Extraction techniques are designed specifically to isolate clastic dispersion trains. Thick mantles of aeolian and water-borne overburden characterise desert lowlands and are a challenge to the exploration geochemist. Techniques showing the most promise in these areas include groundwater geochemistry, vapour geochemistry, surface microlayer geochemistry, geobotany and biogeochemistry which attempt to isolate gaseous and weak hydromorphic, ore-related trace-element dispersions. Termite mound sampling yields convincing results and appears to be an under-utilised geochemical approach. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
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- Date Issued: 1983