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Pioneer Taashwa Gamundani Kudzai Mpakairi Christopher Magadza Shakkie Kativu Elmon Dhlomo 《African Journal of Ecology》2020,58(3):432-445
Climate models project a hot and dry future for Southern Africa. In this research, Maximum Entropy was used to model the extent to which climate change, land cover and distance from water edges may influence current and future distribution of the African skimmer in the mid-Zambezi Valley. Global Biodiversity Information Facility data collected between the years 2000–2019 were used to develop the models. Three models were built: one for current distribution and two for future distribution under Representative Concentration Pathways (RCPs) 2.6 and 6.0. Results revealed that annual precipitation and distance from water edges were the most important predictors of habitat suitability for the African skimmer under current and future climate. Temperature and land cover were least important in explaining current and future distribution of the species. The RCP 2.6 predicted future decrease in suitable habitat for the African skimmer in the mid-Zambezi Valley, while RCP 6.0 predicted future increase in suitable habitat for the species. This research conclusively revealed that precipitation and distance from water edges were consistently key predictors of suitable habitat for the African skimmer. 相似文献
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Stream fish assemblages in relation to environmental factors on a montane plateau (Nyika Plateau,Malawi) 总被引:2,自引:0,他引:2
Wilbert T. Kadye Christopher H. D. Magadza Ngonidzashe A. G. Moyo Shakkie Kativu 《Environmental Biology of Fishes》2008,83(4):417-428
Few studies have examined river fishes of Malawi. This study is one of the first to examine the stream fish assemblages on
the Nyika Plateau in northern Malawi. Twenty four sites were sampled over three different periods in two river systems of
the plateau. Eighteen species were collected and among these was Hippopotamyrus ansorgii, the first collection of this species in the Lake Malawi catchment. Three species, including a non-native trout, were common
in the two systems studied. Correspondence analysis (CA) suggested gradients in species composition related to altitude and
river type. Species succession, from a trout dominated upstream to a downstream dominated by indigenous species, was shown
on the first CA axis. The second CA axis showed the assemblage of the plateau separated by river type. A direct gradient analysis
method, canonical correspondence analysis (CCA), showed the importance of two stream position metrics (stream order and c-link),
depth, water temperature and substrate type in determining species composition. According to variation partitioning in CCA,
the spatial and temporal components respectively explained 46% and 3.6% variation in assemblage composition based on the all
species data matrix, and 48.7% and 2.6% variation in assemblage composition based on the native species data matrix. The species
collected were also discussed in relation to the morphological adaptations in their body forms to the environmental conditions
of the streams studied. 相似文献
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We tested the effect of cultivation on butterfly (Nymphalidae: Charaxes) and beetle (Coleoptera: Scarabaeidae: Cetoniinae) species richness and abundance along a cultivation intensification gradient. Results showed significant differences in species richness and abundance between natural woodlands and cultivated landscapes with larger differences in areas of high cultivation intensity. The results indicate that natural woodland clearing for cultivation purposes has negative impacts on arthropod diversity, a situation more severe in highly intensified cultivated areas. Our results imply that mosaics of different land‐use units, each in a different phase of clearance‐cultivation‐abandonment‐recovery‐clearance cycle could counter the negative effects of cultivation intensity on arthropod diversity. 相似文献
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The generic delimitation of the genus Chlorophytum Ker-Gawl emend. Nordal is discussed and outlined, especially in relation to the genus Anthericum L. Two new names and 39 new combinations for African taxa have been necessitated by the emendated delimitation of the genus. 相似文献
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Shakkie Kativu 《Nordic Journal of Botany》1993,13(5):501-505
Four new species of Chlorophyrum from tropical Africa are described: C. graniticola from Zimbabwe, C. minor and C. perfoliatum from Zambia, and C. velutirzum from Malawi, Tanzania, Zambia and Zaire. 相似文献
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Hulot Florence D. Prijac Antonin Lefebvre Jean-Pierre Msiteli-Shumba Stembile Kativu Shakkie 《Hydrobiologia》2019,837(1):161-175
Hydrobiologia - The transfer of terrestrial organic matter by terrestrial wild and domestic animals when they urinate and defecate directly in Savanna Rivers has already been studied. However, the... 相似文献
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