ALBERT

Description: High urbanization in Sub-Saharan Africa (SSA) has resulted in increased peri-urban groundwater contamination by on-site sanitation. The World Health Organization introduced Water Safety Plans (WSP) towards the elimination of contamination risks to water supply systems; however, their application to peri-urban groundwater sources has been limited. Focusing on Uganda, Ghana, and Tanzania, this paper reviews limitations of the existing water regime in addressing peri-urban groundwater contamination through WSPs and normative attributes of Transition Management (TM) towards a sustainable solution. Microbial and nutrient contamination remain prevalent hazards in peri-urban SSA, arising from on-site sanitation within a water regime following Integrated Water Resources Management (IWRM) principles. Limitations to implementation of WSPs for peri-urban groundwater protection include policy diversity, with low focus on groundwater; institutional incoherence; highly techno-centric management tools; and limited regard for socio-cultural and urban-poor aspects. In contrast, TM postulates a prescriptive approach promoted by community-led frontrunners, with flexible and multi-domain actors, experimenting through socio-technical tools towards a shared vision. Thus, a unified risk-based management framework, harnessing attributes of TM and IWRM, is proposed towards improved WSP implementation. The framework could assist peri-urban communities and policymakers in formulating sustainable strategies to reduce groundwater contamination, thereby contributing to improved access to safe water.

Description: Human cytomegalovirus (HCMV) is an opportunistic pathogen causing disease mainly in immunocompromised patients or after congenital infection. HCMV infection of the respiratory tract leads to pneumonitis in the immunocompromised host, which is often associated with a bad clinical course. The related mouse cytomegalovirus (MCMV) likewise exhibits a distinct tropism for the lung and thus provides an elegant model to study host-pathogen interaction. Accordingly, fundamental features of cytomegalovirus (CMV) pneumonitis have been discovered in mice that correlate with clinical data obtained from humans. Recent studies have provided insight into MCMV cell tropism and localized inflammation after infection of the respiratory tract. Accordingly, the nodular inflammatory focus (NIF) has been identified as the anatomical correlate of immune control in lungs. Several hematopoietic cells involved in antiviral immunity reside in NIFs and their key effector molecules have been deciphered. Here, we review what has been learned from the mouse model with focus on the microanatomy of infection sites and antiviral immunity in MCMV pneumonitis.

Description: Fertilization of soil is needed to fulfill the growing demand for livestock feed and human food requirements. However, fertilization has short and long-term impacts on the soil microbiota. These, in turn, may influence plant viability and growth. We investigated the soil microbiota of a 27-year field trial, focusing on the influences of mineral nitrogen (N) fertilization, different composts and combinations of compost plus mineral N as soil amendments. Two N rates (0 and 80 kg per ha) and four different composts (urban organic waste compost (OWC) green waste compost (GC), farmyard manure (MC) compost and sewage sludge compost (SSC)) were used. Soil samples for this study were taken in 2018 after the growing season of maize. In addition to maize yield, the effects on soil physicochemical properties and the soil microbiota were analyzed. There was a trend for increased maize yields for all fertilizers; however, only the application of GC and SSC in combination with mineral N fertilizer showed significant effects. The different organic amendments influenced physicochemical soil properties. Phosphorus concentrations were three times higher in plots receiving SSC (≈312 mg kg−1) and SSC + N (≈297 mg kg−1) than control (≈89 mg kg−1) or mineral N fertilizer (≈97 mg kg−1) alone. Magnesium concentrations in plots treated with SSC (≈74 mg kg−1) were lower compared to soils treated with GC and MC, respectively (≈135 mg kg−1 and 126 mg kg−1). Bacteria exceeded the fungal community in terms of both richness and diversity. While the bacterial community composition differed significantly among the treatments, the fungal community composition was rather unaffected. Our conclusion is that composts produced from various substrates serve as valuable nutrient sources for plants and can partially substitute mineral N. In addition, composts increased soil microbial biomass and modulated the composition of the soil’s microbial community.

Description: Within the CO2 time series measured at the Environmental Research Station Schneefernerhaus (UFS), Germany, as part of the Global Atmospheric Watch (GAW) program, pollution episodes are traced back to local and regional emissions, identified by δ13C(CO2) as well as ratios of CO and CH4 to CO2 mixing ratios. Seven episodes of sudden enhancements in the tropospheric CO2 mixing ratio are identified in the measurements of mixing/isotopic ratios during five winter months from October 2012 to February 2013. The short-term CO2 variations are closely correlated with changes in CO and CH4 mixing ratios, achieving mean values of 6.0 ± 0.2 ppb/ppm for CO/CO2 and 6.0 ± 0.1 ppb/ppm for CH4/CO2. The estimated isotopic signature of CO2 sources (δs) ranges between −35‰ and −24‰, with higher values indicating contributions from coal combustion or wood burning, and lower values being the result of natural gas or gasoline. Moving Keeling plots with site-specific data selection criteria are applied to detect these pollution events. Furthermore, the HYSPLIT trajectory model is utilized to identify the trajectories during periods with CO2 peak events. Short trajectories are found covering Western and Central Europe, while clean air masses flow from the Atlantic Ocean and the Arctic Ocean.

Description: Socio-institutional factors are poorly addressed in the risk assessment of groundwater contamination. This paper contributes to the development of a socio-institutional assessment framework based on a case study of contamination by on-site sanitation (OSS) in an informal settlement of Bwaise (Kampala, Uganda). We conducted a snapshot survey of the recent extent of groundwater contamination by OSS using microbial and hydro-chemical indicators. Through transition arenas and key informant interviews, we investigated the socio-institutional drivers of the contamination. Overall, 14 out of the 17 sampled groundwater sources tested positive for Escherichia coli during the wet season. Nitrate concentrations at four sources exceeded the World Health Organization guideline value (50 mg/L), attributed to OSS. Despite the high contamination, the community highly valued groundwater as an alternative to the intermittent municipal water supply. We deduced six drivers of groundwater contamination, including land-use management, user attributes, governance, infrastructure management, groundwater valuation, and the operating environment (“LUGIVE”). Qualitative indicators for each of the drivers were also construed, and their interlinkages presented in a causal loop diagram, representing a socio-institutional assessment framework. The framework can help policymakers and the community to analyze various socio-institutional control levers to reduce the risk of groundwater contamination by OSS in informal settlements.