The IAHS Science for Solutions decade, with Hydrology Engaging Local People IN one Global world (HELPING)

The new scientific decade (2023-2032) of the International Association of Hydrological Sciences (IAHS) aims at searching for sustainable solutions to undesired water conditions – whether it be too little, too much or too polluted. Many of the current issues originate from global change, while solutions to problems must embrace local understanding and context. The decade will explore the current water crises by searching for actionable knowledge within three themes: global and local interactions, sustainable solutions and innovative cross-cutting methods. We capitalise on previous IAHS Scientific Decades shaping a trilogy; from Hydrological Predictions (PUB) to Change and Interdisciplinarity (Panta Rhei) to Solutions (HELPING). The vision is to solve fundamental water-related environmental and societal problems by engaging with other disciplines and local stakeholders. The decade endorses mutual learning and co-creation to progress towards UN sustainable development goals. Hence, HELPING is a vehicle for putting science in action, driven by scientists working on local hydrology in coordination with local, regional, and global processes

Independent and combined effects of improved water, sanitation, and hygiene, and improved complementary feeding, on child stunting and anaemia in rural Zimbabwe: a cluster-randomised trial.

BACKGROUND: Child stunting reduces survival and impairs neurodevelopment. We tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF) on stunting and anaemia in in Zimbabwe. METHODS: We did a cluster-randomised, community-based, 2 × 2 factorial trial in two rural districts in Zimbabwe. Clusters were defined as the catchment area of between one and four village health workers employed by the Zimbabwe Ministry of Health and Child Care. Women were eligible for inclusion if they permanently lived in clusters and were confirmed pregnant. Clusters were randomly assigned (1:1:1:1) to standard of care (52 clusters), IYCF (20 g of a small-quantity lipid-based nutrient supplement per day from age 6 to 18 months plus complementary feeding counselling; 53 clusters), WASH (construction of a ventilated improved pit latrine, provision of two handwashing stations, liquid soap, chlorine, and play space plus hygiene counselling; 53 clusters), or IYCF plus WASH (53 clusters). A constrained randomisation technique was used to achieve balance across the groups for 14 variables related to geography, demography, water access, and community-level sanitation coverage. Masking of participants and fieldworkers was not possible. The primary outcomes were infant length-for-age Z score and haemoglobin concentrations at 18 months of age among children born to mothers who were HIV negative during pregnancy. These outcomes were analysed in the intention-to-treat population. We estimated the effects of the interventions by comparing the two IYCF groups with the two non-IYCF groups and the two WASH groups with the two non-WASH groups, except for outcomes that had an important statistical interaction between the interventions. This trial is registered with ClinicalTrials.gov, number NCT01824940. FINDINGS: Between Nov 22, 2012, and March 27, 2015, 5280 pregnant women were enrolled from 211 clusters. 3686 children born to HIV-negative mothers were assessed at age 18 months (884 in the standard of care group from 52 clusters, 893 in the IYCF group from 53 clusters, 918 in the WASH group from 53 clusters, and 991 in the IYCF plus WASH group from 51 clusters). In the IYCF intervention groups, the mean length-for-age Z score was 0·16 (95% CI 0·08-0·23) higher and the mean haemoglobin concentration was 2·03 g/L (1·28-2·79) higher than those in the non-IYCF intervention groups. The IYCF intervention reduced the number of stunted children from 620 (35%) of 1792 to 514 (27%) of 1879, and the number of children with anaemia from 245 (13·9%) of 1759 to 193 (10·5%) of 1845. The WASH intervention had no effect on either primary outcome. Neither intervention reduced the prevalence of diarrhoea at 12 or 18 months. No trial-related serious adverse events, and only three trial-related adverse events, were reported. INTERPRETATION: Household-level elementary WASH interventions implemented in rural areas in low-income countries are unlikely to reduce stunting or anaemia and might not reduce diarrhoea. Implementation of these WASH interventions in combination with IYCF interventions is unlikely to reduce stunting or anaemia more than implementation of IYCF alone. FUNDING: Bill & Melinda Gates Foundation, UK Department for International Development, Wellcome Trust, Swiss Development Cooperation, UNICEF, and US National Institutes of Health.The SHINE trial is funded by the Bill & Melinda Gates Foundation (OPP1021542 and OPP113707); UK Department for International Development; Wellcome Trust, UK (093768/Z/10/Z, 108065/Z/15/Z and 203905/Z/16/Z); Swiss Agency for Development and Cooperation; US National Institutes of Health (2R01HD060338-06); and UNICEF (PCA-2017-0002)

Management of Edible Stinkbugs (Encosternum delegorguei) in Bikita District, Zimbabwe

Forest products resources in most communal areas of developing countries are common property resources. Forests are important for the exploitation of timber and non-timber forest products such as industrial wood, fuel wood, grass, fibre, medicinal herbs and roots, harvesting of fauna associated with forests such as caterpillars, locusts, bees (honey) and animal habitats. The management of these forest resources at the community level appears to be done at best through communal system. Community-based natural resource management is a potential solution to the inter-related problems of poverty alleviation if it is based on sound management principles that incorporate transparency, efficiency, accountability and democracy. This paper explores the management of edible stinkbugs (Encosternum delegorguei) in the Jiri Forest of Bikita district in Zimbabwe. Research findings reveal that traditional institutional arrangements composed of chiefs, headmen, village heads and villagers that have been in place for a long time are coherent and have been able to withstand pressures on forest degradation.Key words: common property resources, traditional institutions, forest based livelihood

IMPACT OF CLIMATE CHANGE ON RESERVOIR RELIABILITY

Research and observations indicate that increases in atmospheric carbon dioxide (CO2) are raising global and regional temperatures, and producing changes in other climate variables that drive the terrestrial hydrological cycle, most notably precipitation and potential evaporation. This paper presents results of a study conducted to evaluate the possible impacts of climate change due to doubling of atmospheric carbon dioxide on the reliability of Mazowe reservoir in Zimbabwe. The reservoir supplies most of its water to citrus plantations. Thirty years (1961-1990) of hydrological data (reservoir inflows) and meteorological data were collected from the Zimbabwe National Water Authority (ZINWA) and Department of Meteorological Services, respectively. outputs from the Canadian Climate Centre (CCC) model for the 2CO2 temperature and rainfall scenarios were used in the study. The Penman model was used to estimate potential evapotranspiration, while reservoir catchment runoff was simulated using the Pitman lumped conceptual model. Research findings revealed that doubling of CO2 in 2050 would significantly increase mean monthly temperature by 3\ub0C, potential evapotranspiration (11.8%), rainfall (15%), runoff (23.5%) and annual reservoir yield (20.4%) at the 10% risk level. Based on the research findings, appropriate mitigation measures should be employed to minimise high rates of evaporation from the reservoir. on the other hand, the predicted high reservoir yield requires an increase in water use activities such as extension of irrigated area.La recherche et les observations indiquent que l\u2019accroissement du dioxyde de carbone atmosph\ue9rique (CO2) \ue9l\ue8ve les temp\ue9ratures mondiale et r\ue9gionale, et produit des changements dans d\u2019autres variables climatiques qui d\ue9terminent le cycle hydrologique de la terre, notamment la pr\ue9cipitation et l\u2019\ue9vaporation potentielle. Cet article pr\ue9sente les r\ue9sultats d\u2019une \ue9tude men\ue9e pour \ue9valuer les impacts possibles du changement climatique d\ufb \ue0 un doublement du dioxyde de carbone atmosph\ue9rique sur la fiabilit\ue9 du r\ue9servoir Mazowe au Zimbabwe. Le r\ue9servoir alimente en eau les plantations d\u2019agrumes. Trente ans (1961-1990) de donn\ue9es hydrologique (apports au r\ue9servoir) et m\ue9t\ue9orologique ont \ue9t\ue9 recueillies aupr\ue8s de l\u2019Autorit\ue9 Nationale de l\u2019Eau du Zimbabwe (ZINWA) et du D\ue9partement des services m\ue9t\ue9orologiques, respectivement. Les r\ue9sultats du mod\ue8le du Centre Climatologique Canadien (CCC) pour la temp\ue9rature 2CO2 et la pluviom\ue9trie ont \ue9t\ue9 utilis\ue9s dans l\u2019\ue9tude. Le mod\ue8le de Penman a \ue9t\ue9 utilis\ue9 pour estimer l\u2019\ue9vapotranspiration potentielle, alors que la r\ue9serve des eaux de ruissellement du bassin versant a \ue9t\ue9 simul\ue9e \ue0 l\u2019aide du mod\ue8le conceptuel de Pitman. Les r\ue9sultats de recherche ont r\ue9v\ue9l\ue9 que le doublement du CO2 en 2050 augmenterait de mani\ue8re significative la temp\ue9rature moyenne mensuelle de 3\ub0C,l\u2019\ue9vapotranspiration potentielle (11.8%), les pr\ue9cipitations (15%), le ruissellement (23.5%) et le rendement en r\ue9serve annuelle (20.4%) au niveau de risque de 10% .Se basant sur des r\ue9sultats de la recherche, des mesures appropri\ue9es de r\ue9duction du taux d\u2019\ue9vaporation \ue9lev\ue9 du r\ue9servoir devraient \ueatre prises. D\u2019autre part, le haut rendement de la r\ue9serve pr\ue9vu requiert une augmentation des activit\ue9s de consommation d\u2019eau telle que l\u2019extension de la zone irrigu\ue9e

IMPACT OF CLIMATE CHANGE ON RESERVOIR RELIABILITY

Research and observations indicate that increases in atmospheric carbon dioxide (CO2) are raising global and regional temperatures, and producing changes in other climate variables that drive the terrestrial hydrological cycle, most notably precipitation and potential evaporation. This paper presents results of a study conducted to evaluate the possible impacts of climate change due to doubling of atmospheric carbon dioxide on the reliability of Mazowe reservoir in Zimbabwe. The reservoir supplies most of its water to citrus plantations. Thirty years (1961-1990) of hydrological data (reservoir inflows) and meteorological data were collected from the Zimbabwe National Water Authority (ZINWA) and Department of Meteorological Services, respectively. outputs from the Canadian Climate Centre (CCC) model for the 2CO2 temperature and rainfall scenarios were used in the study. The Penman model was used to estimate potential evapotranspiration, while reservoir catchment runoff was simulated using the Pitman lumped conceptual model. Research findings revealed that doubling of CO2 in 2050 would significantly increase mean monthly temperature by 3°C, potential evapotranspiration (11.8%), rainfall (15%), runoff (23.5%) and annual reservoir yield (20.4%) at the 10% risk level. Based on the research findings, appropriate mitigation measures should be employed to minimise high rates of evaporation from the reservoir. on the other hand, the predicted high reservoir yield requires an increase in water use activities such as extension of irrigated area.La recherche et les observations indiquent que l’accroissement du dioxyde de carbone atmosphérique (CO2) élève les températures mondiale et régionale, et produit des changements dans d’autres variables climatiques qui déterminent le cycle hydrologique de la terre, notamment la précipitation et l’évaporation potentielle. Cet article présente les résultats d’une étude menée pour évaluer les impacts possibles du changement climatique dû à un doublement du dioxyde de carbone atmosphérique sur la fiabilité du réservoir Mazowe au Zimbabwe. Le réservoir alimente en eau les plantations d’agrumes. Trente ans (1961-1990) de données hydrologique (apports au réservoir) et météorologique ont été recueillies auprès de l’Autorité Nationale de l’Eau du Zimbabwe (ZINWA) et du Département des services météorologiques, respectivement. Les résultats du modèle du Centre Climatologique Canadien (CCC) pour la température 2CO2 et la pluviométrie ont été utilisés dans l’étude. Le modèle de Penman a été utilisé pour estimer l’évapotranspiration potentielle, alors que la réserve des eaux de ruissellement du bassin versant a été simulée à l’aide du modèle conceptuel de Pitman. Les résultats de recherche ont révélé que le doublement du CO2 en 2050 augmenterait de manière significative la température moyenne mensuelle de 3°C,l’évapotranspiration potentielle (11.8%), les précipitations (15%), le ruissellement (23.5%) et le rendement en réserve annuelle (20.4%) au niveau de risque de 10% .Se basant sur des résultats de la recherche, des mesures appropriées de réduction du taux d’évaporation élevé du réservoir devraient être prises. D’autre part, le haut rendement de la réserve prévu requiert une augmentation des activités de consommation d’eau telle que l’extension de la zone irriguée