Think Piece. Human Vulnerability to Depleting Water Resources in Cameroon: Sensitisation approaches

The ecological diversity of Cameroon is linked to its geology, morphology and climate. This diversity is unique, not only in the central African region, but on the African continent as a whole. It ranges from wetlands along the Atlantic coast in the south, through equatorial rain forest, to savanna in the Sahel, and then to desert scrub in the southern fringes of the Sahara Desert at the extreme northern end of the country around Lake Chad (Figure 1). This uniqueness is also reflected by the variations in the culture of the people who speak over 250 languages. The determinant factor for the distribution and concentrations of both urban and rural populations, as well as their livelihood, is accessibility to water supplies. The potential of these resources is dependent on the types of aquifers which, according to Ayonghe (1998), are recharged by rainfall in sedimentary rocks, fault zones in Precambrian crystalline rocks, weathered Cretaceous granites and Tertiary volcanic rocks. Phreatic aquifers constitute the main catchment areas in the country, especially along the dominant morphological high termed the Cameroon Volcanic Line. According to Ntasin and Ayonghe (2001) rivers radiate from this major catchment in all directions (Figure 1). The groundwater within this main catchment area has, over the past few decades, been observed to be under stress – as indicated by the depleting volumes of water in the rivers.  Complete or total disappearances of perennial springs, leading to dried-up streams and drastic decreases in the volume of rivers, especially during dry seasons, are common (Ayonghe, 1998). In fact, hydrogeological events within the last 10 years have left almost every critical hydrological observer with the conclusion that the stock of water resources in the country has been declining. The marked reduction in the size of Lake Chad,located at the northern end of the country, the growing potable water crises in both urban and rural communities, the reducing volumes of water in nearly all rivers leading to shortages of electricity supplies from hydroelectric generating stations, and the increasing southward migration of communities from the north, are also strong pointers to the fact that a major water crisis is looming. Consequently, there is need to pay urgent attention to this problem. This paper constitutes a critical review of the causes of the depleting water  resources, the trends related to some of the causes, projected impacts in the near future, and the possible impacts of such trends.&nbsp

Defluoridation of fluoride-rich groundwater in Mayo Tsanaga River Basin-Cameroon using locally produced bone char

With fluoride-rich groundwater causing a climatic-dependent fluorosis in Mayo-Tsanaga River Basin, the overall objective of this study was to reduce fluoride concentrations in drinking water to acceptable levels thereby improving the resilience of the population to this climate change induced pathology. The specific objectives were to: (1) assess water chemistry in the study area to re-affirm the undesirable fluoride levels; (2) assess the impact of seasons on the concentrations of fluoride; (3) construct and evaluate the performance of a household bone char-based adsorption defluoridation filter. A combination of hydrogeochemical and engineering analyses demonstrated that the groundwater is predominantly Ca+Mg-HCO3 type, which contains as much as 6.73 mg/l of undesirable concentrations of geogenic fluoride. These concentrations increased with elevated pH, electrical conductivity and in the dry season, and were reduced to less than 0.2 mg/l when the groundwater was subjected to filtration through 300 g of 0.2-0.8 mm faction of charred cow bones in a home-based defluoridation filter. The bone char in the filter can effectively reduce fluoride concentration to less than 0.7 mg/l, which is the local threshold limit, without negative impact on the organoleptic (taste, color and odor) characteristics of drinking water. Compared with the commercially activated carbon, the bone char has an additional capacity of adsorbing fluoride at a rate of 4 mg/liter in 30 minutes, which indicates that with a defined saturation time, the bone char filter can protect the population against climate change-induced fluoride enrichment in drinking water.Keywords: Groundwater. geogenic fluoride. climate dependent fluorosis. bone char defluoridation. water chemistr

Defluoridation of fluoride-rich groundwater in Mayo Tsanaga River Basin-Cameroon using locally produced bone char

With fluoride-rich groundwater causing a climatic-dependent fluorosis in Mayo-Tsanaga River Basin, the overall objective of this study was to reduce fluoride concentrations in drinking water to acceptable levels thereby improving the resilience of the population to this climate change induced pathology. The specific objectives were to: (1) assess water chemistry in the study area to re-affirm the undesirable fluoride levels; (2) assess the impact of seasons on the concentrations of fluoride; (3) construct and evaluate the performance of a household bone char-based adsorption defluoridation filter. A combination of hydrogeochemical and engineering analyses demonstrated that the groundwater is predominantly Ca+Mg-HCO3 type, which contains as much as 6.73 mg/l of undesirable concentrations of geogenic fluoride. These concentrations increased with elevated pH, electrical conductivity and in the dry season, and were reduced to less than 0.2 mg/l when the groundwater was subjected to filtration through 300 g of 0.2-0.8 mm faction of charred cow bones in a home-based defluoridation filter. The bone char in the filter can effectively reduce fluoride concentration to less than 0.7 mg/l, which is the local threshold limit, without negative impact on the organoleptic (taste, color and odor) characteristics of drinking water. Compared with the commercially activated carbon, the bone char has an additional capacity of adsorbing fluoride at a rate of 4 mg/liter in 30 minutes, which indicates that with a defined saturation time, the bone char filter can protect the population against climate change-induced fluoride enrichment in drinking water

The influence of seasonal variations on malaria prevalence in Mount Cameroon Region: A review

Malaria is Cameroon's most serious and complex public health problem. Its transmission is usually associated with topography, climate and socio-economic conditions. The problem of the disease is aggravated by changing climate, poverty, and lack of efficient controlling mechanisms. Also, the emergence of new parasite strains, expansion of host range due to human population growth and movement, land use change, increasing vectorial capacity, and deteriorating public health infrastructures contribute to the spread of the disease. Due to climate and ecological diversity, there is apparent variation and instability in the epidemiology of its transmission and prevalence. All age groups are particularly vulnerable to even mild malaria during epidemics. The challenges posed by seasonal changes on malaria prevalence urgently demand re-visiting control measures and policy of urban planning. This paper reviews previous studies on seasonal variations and the prevalence of malaria in Mount Cameroon Region. Generally, seasonal changes from these studies are highly linked to malaria prevalence in the region. We also present in this review new measures that need to be taken to harness existing malaria control measures and evade possible malaria epidemics in the region and Cameroon as a whole. We proposed future studies which involve monitoring and modeling the influence of climate change and land use changes on the malariology indices in the Mount Cameroon Region.Keywords: malaria, prevalence, seasonal variationsJOURNAL OF THE CAMEROON ACADEMY OF SCIENCES Vol. 11 No. 1 (2013

Forensic assessment of the 1999 Mount Cameroon eruption, West-Central Africa

The 28March to 22 April 1999 eruption ofMount Cameroon volcano in southwest Cameroon occurred frommultiple vents along fissures at two sites. Vents opened first at the upper site 1 (2650 m) and were more explosive than vents at the lower site 2 (1500m), which were more effusive. Earthquakes, lava flows, tephra fall, ballistics and gas emissions affected the volcano's west and south flanks, including forests, plantations, stock animals, water supplies, coastal communities and their people. Through an analysis of existing published data and new interview data, we provide an overview of the environmental, social and economic consequences of these hazards on infrastructure, human health, and socio-economic and agricultural activities of the four coastal communitiesmost affected by the eruption: Batoke, Bakingili,Debundscha and Idenau. The collected data provide amore detailed description of the short- and long-term direct and indirect effects of the eruption and response than has been provided to date. Sedimentation of tephra and ballistics from site 1 produced both short-term and longlasting impacts on people, through the contamination of plants and water supplies, which induced impacts on human health and commercial activities. A ~9.2 km long lava flow erupted from site 2 received significant short-termattention as it severed the only arterial coastal highway, forced the evacuation of some 600 residents of Bakingili, and interrupted commerce between communities. The agricultural sector also suffered due to burning of crops and soils. The only obvious significant benefit of the eruption appears to be that the long lava flowhas become a tourist attraction, responsible for bringing in money for food, drink and lodging. However, the longterm cascading effects caused by the hazards have proven to be more severe than the immediate direct and indirect effects during the eruption

Remote sensing study of the Mt Cameroon volcano, SW Province, Cameroon

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