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In urban areas, human activities result in the discharge of a variety of chemical substances into the environment. This affects soil quality, plant species diversity and human security. To suggest appropriate management strategies that ensure soil quality and human security amid urbanization, this study assessed the relationship between macrophyte diversity and some soil characteristics of wetlands that are adjacent to urban, peri-urban and rural areas in Bamenda Municipality, Cameroon. Plant communities were sampled for species composition and relative abundance, using the Braun-banquet method. Species richness was evaluated using Simpson’s diversity index. Twenty-one soil samples (0–25 cm depth) were randomly collected within the wetlands and analyzed for their physicochemical characteristics using standard methods. The hierarchical cluster analysis (HCA) was used to group the wetlands under managing units. The dominant species ranked in order of abundance in the rural wetland were Raphia farinifera > Ludwigia hexandra > Coix spp. > Leersia hexandra > Ehchinochloa paramidelis. The Peri-urban wetland dominant species stood at Commelina bengalensis > Leersia hexandra > Cyperus distance > Ehchinochloa pyramidalis. In the Urban segment, Pennisetum purpureum > Echinochloa pyramidalis > Tithonia diversifolia > Leersia hexandra were the abundant species. The Simpson index of diversity was 0.94 for the urban and 0.96 for the peri-urban and rural sites respectively. The soils were slightly acidic with pH KCl ranging from 4.87 to 5.41. From the coefficient of variability classes, Sand, pH-H2O, pH-KCl, and Na consistently varied slightly across the three sites. Two significant clusters (management units) representing a combination of urban, and peri-urban/rural were formed from the hierarchical dendrograms. The Mann–Whitney U test revealed a significant (P < 0.05) lower exchange acidity in the rural than the urban sites indicating contamination of the urban site, reducing its macrophyte diversity. Intensification and extension of urbanisation are gradually reducing the macrophyte diversity and also contaminating the soils of the wetlands of the Bamenda municipality in Cameroon, warranting monitoring. The chemical composition of soils in the urban cluster needs early remediation by encouraging the planting and monitoring of certain plants that can already take up the elements.

Onchocerciasis is a parasitic infection affecting a relatively small population globally but has very devastating pathological outcomes. Ivermectin and recently moxidectin are the only drugs approved for clinical management of the disease, both of which have several limitations. In particular, they are efficacious against microfilariae (microfilaricidal) with no activity against adult worms (nonmacrofilaricidal). Promising anthelmintic activity has been reported in some lichens. This study investigated three lichens, Usnea articulata, Parmotrema tinctorum, and Heterodermia obscurata, found on Mount Cameroon, for potential macrofilaricidal activity. Organic extracts were screened for anti-Onchocerca activity against Onchocerca ochengi isolated from cattle skin using worm motility and MTT formazan assays. Toxicity of highly active extracts was investigated on monkey kidney epithelial (LLCMK2) cells and in BALB/c mice (2000 mg/kg body weight) including effects on liver enzymes. The methanol extract of P. tinctorum (Pammet) was the most active against adult male worms ( I C 50 = 8.1  μg/mL) with the highest selectivity index ( SI = 21.3 ). U. articulata was the most active against the adult female ( I C 50 = 36.3  μg/mL) but had a low SI value (3.4). No mortality and no adverse effects were recorded in the acute toxicity test. These two most active extracts had no significant effect on liver enzymes, alanine aminotransferase, and aspartate ( P values < 0.05), but a high AST : ALT ratio (2.59) for Pammet indicates likely reversible adverse hepatic toxicity. The high macrofilaricidal activity and selectivity of P. tinctorum suggest it is a potential source of new macrofilaricides which should be further investigated to identify its bioactive constituents.

AimsIn urban areas, human activities result to the discharge of a variety of chemical substances to the environment, playing a substantial role in soil quality, plant species diversity and human security. In order to suggest appropriate management strategies that ensures soil quality, their sustainable utilization and human security in the midst of urbanization, this study assesses the relationship between macrophyte diversity and some soil characteristics of wetlands in Bamenda Municipality, Cameroon at different stages of urbanization. It examines (i) macrophyte diversity and soil characteristics of wetlands adjacent urban and peri-urban areas. MethodsPlant communities were sampled for species composition and relative abundance, using the Braun-banquet method. Species richness was evaluated using the Simpson’s diversity index. Twenty-one soil samples (0 - 25 cm depth) were also randomly collected within the wetlands and analyzed for their physico-chemical characteristics using standard methods. The hierarchical cluster analysis (HCA) was used to group the area under managing units. ResultsFrom the results, 50 macrophytes species distributed in 28 families were documented in the area. The species observed were mostly emergent herbaceous plants (grasses) with only few shrubs and trees. The Simpson indices of diversity were 0.94 and 0.96 for the urban and control sites, respectively. The soils were slightly acidic. Sand, pH-H2O, pH-KCl, Na were consistently least variable across the three sites. Two significant clusters representing a combination of urban and peri urban/rural were formed from the hierarchical dendrograms for classification of the chemical variables for the surface soils wetlands with associations to plants species. The Mann-Whitney U test, revealed a significant lower (P <0.05) concentration of the chemical constituents of the control site and the urban sites indicating contamination.ConclusionIntensification and extension of urbanisation is reducing the diversity of the wetlands of the Bamenda municipality warranting monitoring.

Tree composition and ecological structure were assessed in Akak forest area with the objective of assessing the floristic composition and the regeneration potentials. The study was carried out between April 2018 to February 2019. A total of 49 logged stumps were selected within the Akak forest spanning a period of 5 years and 20m x 20m transects were demarcated. All plants species &lt;1cm and above were identified and recorded. Results revealed that a total of 5239 individuals from 71 families, 216 genera and 384species were identified in the study area. The maximum plants species was recorded in the year 2015 (376 species). The maximum number of species and regeneration potentials was found in the family Fabaceae, (99 species) and (31) respectively. Baphia nitida, Musanga cecropioides and Angylocalyx pynaertii were the most dominant plants specie in the years 2013, 2015 and 2017 respectively. The year 2017 depicts the highest Simpson diversity with value of (0.989) while the year 2015 show the highest Simpson dominance with value of (0.013). The year 2013 show a highest Shannon evenness with value of (0.4879). Logged compartment 2015 has a highest fisher alpha with value of 137.7 depicting highest specie richness The Shortest Euclidean distance of 123.44 between year 2013 and 2017 show that they both have many plants species that are similar. Evidently the forest area is very rich in trees in the lower diameter classes, and the structure of the Akak forest area is J reverse indicating that the forest is growing to climax.

Concern about maintaining the biodiversity of lichen communities' species has been an issue with lichenologists for many years. Many of the understudied regions face increasing threats from urban development, pollution, and potentially climate change, among other factors. The objective of this study was to examine the diversity of lichens on Mt. Cameroon. To achieve this objective, eight collection sites were surveyed on two flanks of the mountain at elevations ranging from 3 to 2178 m above sea level. The visual estimate sampling method using circular plots was adopted for the survey. Voucher specimens were collected in triplicate and deposited in the herbaria in Limbe and the University Buea. Lichens were identified by studying the morphology and chemical spot test. The morphology of the thallus and reproductive structures were examined under the stereomicroscope at 10×. The K-test, Ctests and KC-spot test were performed for each specimen with KOH and Ca(OCl) 2 . The abundance rating scale, species diversity, similarity and richness indices were computed. Identification by molecular, morphological and chemical spot tests produced a total of 89 species, 22 site-specific species, 52 genera belonging to 27 families and 11 orders. Four lichen specimens were identified to genus level and eighty-five to species level. According to the Cameroon lichen database, 82 of these are new discoveries. Parmeliaceae, Heterodermia, Usnea and Dirinaria applanata dominated the area. The identified species occurred in six growth forms and from nine substrates types. Foliose and corticolous lichens were most represented. Among the sites surveyed, Upper Buea situated on the leeward flank at high altitude >1000 m, recorded the highest diversity and site-specific species.