Epiphytes constitute an element of climate regulation in the tropical zone. In Cameroon, the decline in forest area of about 220,000 ha, partly due to urbanization, has been observed. The research aim was to characterize the epiphytic flora of the urban ecosystem of Douala. Four zones represented by nine neighbourhoods were chosen for the surveys. Four transects of a maximum distance of 500 m were scanned on each neighbourhood. Epiphytes were checked by direct visual observation on the host trees. Epiphytes’s life forms were determined, and the fixation zone was established using the Johanson method. A total of 72 species of epiphytes were identified, dominated by Polypodiaceae. Casual epiphytes were the most abundant life-form, and true epiphytes were the least, divided into Polypodiaceae, Dryopteridaceae, and Orchidaceae within the genus Calyptrochillium . Twenty-two species of host trees were inventoried in the study area. Rutaceae was the most represented family with six species. True epiphytes were abundant in seaside and peripheral areas, while Casual and Hemiepiphytes were in the central sectors. The domestication of epiphytes must be initiated in order to preserve their diversity in urban ecosystem.
The effect of different concentrations of Indole acetic acid (IAA) on spore germination and gametophyte development of Ceratopteris thalictroides , a leptosporangiate fern of the family Pteridaceae found at the marshy places near Sitamata sanctuary in Rajasthan, was observed. The highest spore germination percentage was recorded in the 2 to 6 ppm concentration range of IAA, with minimum in the 10 ppm concentration. The number of cells in the protonemal filament and percentages of 2-D growth, spatulate and cordate gametophyte were highest in the 1 ppm concentration of IAA, followed by the control. Maximum percentages of archegonia and antheridia development were also recorded in 1 ppm IAA and control treatments, with percentages gradually declining from 2 to 10 ppm treatments. However, the maximum percentage of sporophyte development was recorded in 4 and 6 ppm IAA treatments.
Adiantum capillus-veneris is a cosmopolitan, globally distributed terrestrial fern in warm temperate to tropical regions.It is also widely cultivated in indoor and outdoor settings.The natural habitat of A. capillus-veneris includes limestone rocky places with consistent sources of water, including shady alkaline, moist cliffs and on vertical surfaces in moist forested locations, preferably with calcareous soils; however, it is also found on sandstone.There is increasing evidence that it is relatively tolerant of desiccation stress, under appropriate environmental circumstances.This is a report of a laboratorybased study of the photophysiology of A. capillus-veneris, including an analysis of the effects of leaf excision and varied degrees of desiccation on leaf resilience and physiological properties, with comparisons to Nephrolepis exaltata (L.) Schott and Adiantum tibeticum Ching.Evidence is also presented on the rate of excised leaf desiccation in relation to the role of humidity in mitigating stress due to limited access to moisture.The ecophysiologial variables examined include: Variations in photosynthesis rate relative to light intensity, dark respiration rate, leaf parameters including chlorophyll concentration index (CCI), specific leaf area (SLA), and leaf fluorescence evidence for functioning of photosystem II (PS II).
The production of macrophyte biomass holds a crucial role in supporting diverse life forms within wetland ecosystems. However, this biomass production is intricately tied to hydrology of the inland wetland system, which in turn is driven by the local climate's seasonal patterns. The response of macrophyte biomass production to seasonal changes in water depth, influenced by rainfall patterns and air temperatures in the freshwater King’wal riverine wetland of Kenya, remains unclear. This study investigated seasonal productivity of emergent macrophytes in relation to water depth and human-induced disturbances in the King’wal riverine wetland of Kenya. Water depths were measured across four study sites using a graduated meter-ruler. Monthly harvesting of above-ground emergent macrophyte biomass took place just above the soil surface in three 1 m2 quadrats at each of the four sites, spanning from September 2021 to August 2022. The harvested macrophyte samples were cut, air dried, and oven dried at 65°C to constant weight. The weight was expressed in grams per square meter. Historical rainfall data spanning from 2011 to 2021 was acquired for two stations near the wetland. Daily data for both rainfall and temperature were collected for the study period from three stations: Baraton, Tebeson farm, and Moi University. The Mann-Kendall test was employed, revealing a significant reduction in rainfall (tau = -0.102, P < 0.05) in the area. A negative and significant relationship was established between water depth in the wetland and biomass productivity (rho = - 0.59; P < 0.001). Biomass accumulation and productivity can indicate climate change impacts over a longer period of time. Key words: Rainfall Anomaly Index, Temperature, above ground biomass, Inland wetland, Kenya.
Wetland ecosystems and the fisheries that depend on them are vital to the survival of million individuals in poor nations. Although this habitat is contracting because of heavy pressure brought on by the expansion of the population and the increase of human activity in Cameroon. Yet it is crucial to evaluate the management practices used to ensure its durability. In this study, we look into wetland stakeholders' perspectives. Therefore, it is important to assess the management to make a strategic suggestion for the formulation of a national strategy. Totaling, 277 individuals were interviewed from the Rio del Rey, Ebogo, Barombi, and the Cameroonian portion of Ntem wetlands, and Dschang's municipal lake. The samples were taken utilizing a structured questionnaire between 4 February and 20 July 2001, when fishing was at its peak. Results show that 95.6% of management actors believe that this ecosystem is significant and valuable (χ2=21.965; ddl = 15; P=0.015); furthermore, the results show that 86.7% of respondents are unaware of any laws or other legal instruments that are currently in effect. From one site to another, there were substantial differences in how local management committees were seen (χ2=27.29; P<0.05). Additionally, various institutional issues discussed include the following: weak institutional cooperation (28%)> inadequate legislative policy (24%)> conflicts of interest (21%)> inadequate funding (18%)> lack of political will on the part of the authorities (6%%)> inadequately qualified people (3%). The study also shows that Cameroon's wetland suffers from a lack of adequate restrictions. Consequently, it is essential to implement wetland management strategy. Key words: Wetlands, national strategy, sustainable management, perception, Cameroon.
The aim of the study was to determine how mining operations affected the health of aquatic ecosystems.The investigation was carried out in the diamond, gold, and manganese mining areas of Tortiya, Hiré, and Lauzoua.Leaf litter bags were used to assess breakdown.To further identify macroinvertebrates in the laboratory, leaves from emerged large-mesh bags were preserved in 70% alcohol.The results showed that there was no statistically significant difference in lost masses between small mesh nets and large mesh nets for a foliar species at the same station.The breakdown rates of Alchornea cordifolia in large mesh nets at N'Teko station were significantly higher (p<0.05)than in small mesh nets (0.017 j-1).The majority of the macro-invertebrates found in leaf litter bag were insects and gastropods, with proportions exceeding 50%.Insects dominated the macroinvertebrate group involved in leaf litter decomposition in Lauzoua (91% of associated species) and Hiré (56.5%), whereas gastropods (Mesogastropoda and Basommatophora, 77% of related organisms) were most abundant in Tortiya.The functional feeding groups of macro-invertebrates involved in the breakdown of leaf litter were dominated by predators (46% of species) and scrapers grazers (27% of taxa).Shredders made up only 1% of the species associated with leaf litter.Macro-invertebrates' contribution was significantly higher (Mann -Whitney test, p <0.05) at Bou 1 station.Insects and gastropods made up the majority of the macro-invertebrates involved in litter decomposition.Breakdown rates were relatively low at all stations.
The Bandama River contributes essentially to the well-being of the Ivorian population. Unfortunately its biodiversity is strongly threatened by human activities. In order to assess the water quality of the Bandama River and its impact on fish fauna, a scientific study was carried out from March 2019 to February 2020 in its estuarine zone. Thus, the physico-chemical variables of the water, the contents of Pb, Mn, Fe, Cd and Hg in the water and sediment matrices were measured in the three stations defined for the study. Twenty fish species were selected to assess the level of ecological stress observed on the fish fauna. The analysis of the water variables revealed a fairly oxygenated watercourse with temperature above 25°C, acidic pH, high conductivity and salinity above 10‰. The analysis of heavy metal contents revealed a high enrichment of the Bandama estuary in Mn and Hg due to human activities in the whole catchment area. Ecological stress data indicated high fish stress with negative allometric growth for most economically important fish collected in the Grand-Lahou area. Awareness raising among local communities and management measures should be implemented for the conservation of aquatic species in this freshwater Key Biodiversity Area. Key words: Heavy metals, anthropic activity, conservation, Azagny National Park, coastal wetland.
