Effects of Illegal Artisanal Gold Mining Operations on Groundwater Quality in Ghana: The Case of Ahafo-Ano South District

The general properties and overall chemical quality for potability of groundwater in Ahafo-Ano South District of the Ashanti Region of Ghana have been evaluated. With respect to pH, about 92% of groundwaters were potable while 8% were acidic and not potable. Approximately 4%, 32%, 56% and 8% of sampled groundwater were soft, moderately soft, hard and very hard respectively. The overall chemical quality analysis of groundwaters showed that 20%, 28%, 40%, 4% and 8% had excellent, good, poor, very poor and unsuitable drinking water qualities respectively. Approximately 12%, 40% and 84% of As, Ni and Pb exceeded their respective WHO limits while 32% of Cd and Fe exceeded their respective limits for potable water. These higher concentrations of heavy metals were observed to have occurred in communities with intensive illegal gold mining operations. Inhabitants in these areas could potentially be more predisposed to potential health hazards including cancer, nervous system damage, low IQ in children, reduced growth of foetus and premature birth in pregnant women, and kidney damage. It is expected that illegal artisanal gold mining activities will be banned while policies aimed at providing alternative livelihood be instituted to minimize any potential health hazards on humans in the District

Designing River Diversion Constructed Wetland for Water Quality Improvement

Constructed wetlands are recognized as viable potential technology for reducing pollution load and improving quality of water and wastewater. The use of river diversion wetlands is gaining place for improving quality of river and stream water. However, the design criterion for this category of wetlands has not been fully established, and there is a need to optimize existing approach to enhance operational performance. This chapter presents a step-by-step approach for the design of a typical river diversion constructed wetland intended to remove some pollutants and improve river water quality. The approach focused mainly on water quality objective and outlined simple criteria, guidelines, and model equations for the design procedure of a new river diversion constructed wetland. The design of constructed wetlands is generally an iterative process based on empirical equations. Thus, this approach combines simple equations and procedure for estimating the amount of river water to be diverted for treatment so as to assist the designer in sizing the wetland system. The novel approach presented may be useful to wetland experts as some of the procedures presented are not popular in wetland studies. However, this may improve existing river diversion wetlands’ design and development

Trends and impacts of climate change on crop production in Burkina Faso

Understanding past climate trends and their impacts in the Sahel region is fundamental for climate change (CC) adaptation and mitigation. This study analyses climate trends from 1961 to 2020 in three climatic zones in Burkina Faso and the impacts of CC on five major crops production. Long time series of daily rainfall and temperature data from National Meteorology Agency for the period 1961 to 2020 has been compiled. Crop production data (1984–2020) were retrieved from the agriculture department. Climate temporal variations in each climatic zone were analyzed using extreme climate indices and principal component analysis. Linear regression was used to assess climate impacts on crop production. The results showed a high rainfall variability and changes in temperature extremes in the three zones. The climate window, 1991–2020, was hotter than 1961–1990, while the last decade (2011–2020) was the wettest. Most climate indices (67%) showed significant correlations with crop yields. Dry spells, cool days, cold nights, average daily wet days and rainfall intensity showed positive and negative effects on maize, cowpea, millet and sorghum yields. This study highlights the importance of climate-smart policy promoting drought-resistant and short-duration varieties in addressing the adverse effects of CC on crop production. HIGHLIGHTS The warm tails of the daily temperature distributions are changing faster than the cold tails witnessing a warming climate in Burkina Faso.; Recent decade was wetter across the Sahelian and Sudano-Sahelian zones, supporting rain resumption and the Sahel greening hypothesis.; The major crops were differently affected by climate extremes and were more sensitive to these extremes than the average climate conditions.