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Following Muga and van der Zee (Muga and van der Zee, 2015), we generalize the standard Discontinuous Petrov–Galerkin (DPG) method, based on Hilbert spaces, to Banach spaces. Numerical experiments using model 1D convection-dominated diffusionproblem are performed and compared with Hilbert setting. It is shown that Banach basedmethod gives solutions less susceptible to Gibbs phenomenon. h-adaptivity is implemented with the help of the error representation function as error indicator.
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Fishes of the Lower Lulua River (Kasai Basin, Central Africa): A Continental Hotspot of Ichthyofaunal Diversity under Threat
The ichthyofauna of the Lulua River, a large right bank tributary of the Kasai River in central Africa, is among the most poorly documented in the Kasai ecoregion. To remedy this lack of knowledge, sampling was carried out between 2007 and 2014 along the main channel and in many tributaries. A total of 201 species distributed in 81 genera, 24 families, and 12 orders are reported from the lower reaches of the Lulua. The species richness reported in this study represents a substantially improved documentation of the Lulua ichthyofauna (historically estimated at only 79 species). Here, 129 species are recorded for the first time, bringing the total number of known species to 208. Among these, five have recently been described: Raiamas brachyrhabdotos Katemo Manda, Snoeks, Choca Manda, and Vreven 2018, Distichodus kasaiensis Moelants, Snoeks, and Vreven, 2018, Distichodus polli Abwe, Snoeks, Choca Manda, and Vreven 2019, Epiplatys atractus Van Der Zee, Mbimbi, and Sonnenberg 2013, and Hypsopanchax stiassnyae Van Der Zee, Sonnenberg, and Mbimbi 2015; numerous additional taxa are currently under investigation. Recognized here as a continental hotspot of ichthyofaunal diversity, the Lulua is under extreme threat from exploitation of forest products for building materials, deforestation for shifting agriculture and charcoal exploitation, destructive fishing practices, and mining, all of which are rapidly increasing in the watershed. The present study provides baseline documentation for use in conservation planning and future devel- opmental projects in the Kasai ecoregion in general and Lulua River basin in particular.
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- Award ID(s):
- 1655227
- PAR ID:
- 10327560
- Date Published:
- Journal Name:
- Diversity
- Volume:
- 13
- Issue:
- 341
- ISSN:
- 2291-0557
- Page Range / eLocation ID:
- 1-30
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/https://doi.org/10.3390/d13080341
