Angola is one of the countries with a high rate of waterborne diseases, due to the scarcity and poor quality of water for human consumption. The watercourses are receptors of many effluents, mainly domestic sewage, due to a precarious or inexistent sanitation system and a small number of wastewater treatment plants. Therefore, this study aims: (i) to evaluate the water quality (physicochemical and microbiological parameters) of three Angolan rivers (Kwanza, Bengo and Dande) in locations where water is used as drinking water or abstracted for human consumption; (ii) to develop a new water quality index able to quantitatively express the water quality in those sites; and (iii) to assess the spatial distribution of water pollution through principal component analysis (PCA).Water quality assessment was performed by conducting four field surveys (campaigns I to IV); the first two campaigns took place in the dry season, while the last two ones took place in the rainy season. In the first two campaigns, the water quality was suitable to be treated for the production of drinking water, while in the last two campaigns, the water was unsuitable for that purpose (high levels of faecal coliforms were detected). The water quality index allowed to classify the water as generally excellent (campaigns I and II) and poor (campaigns III and IV). The rudimentary disinfection usually performed by individual water suppliers may improve the water quality, but it was not enough to achieve the parametric values required for human consumption in the rainy season (campaigns III and IV) except for Bengo sites. PCA identified sampling sites with the same water quality patterns, grouping into four groups (Kwanza sites) and two groups (Dande and Bengo sites). Therefore, the results of this study may support decision-makers as regards water supply management in the river stretches under study.The new developed Water Quality Index can support decision-makers in terms of water supply management, especially in countries with a high rate of waterborne diseases (e.g. Angola).

South Atlantic studies referring to non-native taxa are mostly restricted to Argentinean, Brazilian, and South African coasts. In this study we examined the literature to provide a list of sessile marine invertebrates along the Angolan coast, to infer its introduction status according to their biogeographical distribution and natural history. We reported 29 non-native and 7 cryptogenic species, a small number when compared to other South Atlantic regions of similar extension. Half of the non-native species were reported for Luanda. The majority of the introduced species had a northern hemisphere origin, a consequence of the main introduction route being from the North Atlantic/Mediterranean Sea during the Portuguese colonization. This is the first comprehensive assessment of this kind for the Angolan coast and the diversity of introduced species is certainly underestimated. Regular and rigorous assessments and monitoring of introduced marine species will help to understand the vectors, routes and time of introductions.

Policymakers and authorities in Africa are often concerned about economic growth and stability owing to the long history of socioeconomic problems that have bedeviled the continent for years. However, increasing environmental degradation challenges in recent times beckons for adequate attention considering Africa’s vulnerability to climate change and environmental disasters. Thus, the current study examines the illustrious environmental Kuznets curve (EKC) hypothesis in a sectoral composition framework of fossil resources abundance among leading oil-producing African economies, including Algeria, Nigeria, Angola, and Egypt, using a combination of quantile regression (QR) approach and dynamic ordinary least square (DOLS) for data between 1995 and 2016. Based on the empirical results from the study, three main factors significantly increase environmental pollution through CO₂ emissions among the countries, namely: fossil energy consumption, income levels, and the shares of the manufacturing sector in the total gross domestic product (GDP). While income growth exacerbates pollution, the negative impacts of the income square were only significant at the lower and mid quantiles of the understudied periods in the QR estimates. Thus, the EKC hypothesis was not convincingly upheld for the countries as its validity demonstrates significant quantile effects. Furthermore, the tripartite causality nexus among real income, resource rent, and share of the service sector in GDP, which is unobserved in the share of the manufacturing sector, reflect the infamous Dutch disease argument among the resource-dependent countries. Hence, to promote environmental sustainability and address resource dependency toward the actualization of SDGs (1, 8, 12, and 13), the study recommends energy portfolios diversification alongside economic diversification.

This paper investigates the relationship between greenhouse gas emissions, energy consumption, and output growth among African OPEC countries (Libya, Nigeria, Angola, Algeria, Equatorial Guinea, and Gabon) using the panel autoregressive distributed lag model (PARDL) estimated by means of mean group (MG) and pooled mean group (PMG) for the period 1970–2016. The paper estimated three panel models comprising the components of greenhouse gasses which includes nitrous oxide, carbon dioxide (CO2), and methane and examined their relationship with economic growth and energy consumption. The findings of the study showed evidence of a positive impact of economic growth on both CO2 and methane emissions in the long run. Its impact on nitrous oxide emissions although positive was found to be statistically insignificant. Energy consumption was also found to produce an insignificant positive impact on CO2, methane, and nitrous oxide emissions in the long run. In the short run, economic growth exerts a significant positive effect on methane emissions; however, its effect on CO2 and nitrous oxide emissions although positive was found to be statistically insignificant. Energy consumption produces an insignificant impact on all components of greenhouse gasses in the short run. In addition, our empirical results showed the presence of a non-linear relationship between methane emissions and economic growth, confirming the existence of the environmental Kuznets curve (EKC) only in the case of methane emissions model.