Water hyacinths: use them or lose them? Improving human and ecosystem health by bringing the science to the people of Lake Chivero, Zimbabwe

Water hyacinth (WHY), an invasive species in (sub-)tropical inland waters, clogs waterways and affects aquatic life and human activities, in addition, it can facilitate the spread of diseases. On the other hand, water hyacinth can be exploited to produce biofuels and other sources of income. A sustainable solution to water hyacinth encroachment "uses" WHY rather than just trying to "get rid of it". This project will use scientific research, satellite data and stakeholder experiences to co-create such solutions for Lake Chivero, the main source of drinking water for Harare, Zimbabwe's capital. This project is coordinated by Professor Timothy Dube (University of the Western Cape) & Dr. Ing. Marloes Penning de Vries (University of Twente). Consortium partners: University of the Witwatersrand; IHE Delft Institute for Water Education; Environmental Management Agency; Midlands State University; Netherlands Institute of Ecology (NIOO-KNAW)

Water op de Kaart: mobiliseren van mensen, data en beleid om waterkwaliteitsproblemen aan te pakken.

'Vang de Watermonsters' is een Citizen Science project dat de waterkwaliteit in kleine wateren in Nederland in kaart brengt. Door het inzetten van burgers voor metingen van de waterkwaliteit krijgen we een beeld van de waterkwaliteit in kleine wateren in Nederland. Kleine wateren zoals plassen, vennen, sloten en vijvers zitten niet in het standaard meetnet van de Waterschappen. Dit project is opgezet om die blinde vlek te kunnen vullen. Uit voorgaande jaren is gebleken dat de waterkwaliteit voor het overgrote deel in Nederland helaas nog slecht of matig scoort. Voor goede waterkwaliteit is helder water nodig met voldoende onderwaterplanten die als schuil- en broedplaats voor veel onderwaterleven dienen en zuurstof produceren in het water.

De resultaten van 2022 zijn te vinden op: https://nioo.knaw.nl/nl/nieuws/biodiversiteit-sloten-vennen-en-grachten-nog-steeds-in-de-knel

Meer informatie over het project is te vinden op www.vangdewatermonsters.nl

MANTEL (Management of Climatic Extreme Events in Lakes & Reservoirs for the protection of Ecosystem Services) is a Marie Sklodowska-Curie European Joint Doctorate Innovative Training Network that trained a cohort of Early Stage Researchers (ESRs) to investigate the effects of extreme climatic events on water quality. As one of 12 ESRs, Qing's MANTEL project focus on mitigating negative impacts of extreme events on the sustained provision of lake ecosystem services.

The outputs will support stakeholders through development of measures that mitigate the negative consequences of extreme events, including toxic cyanobacterial blooms, and runoff induced high nutrient loads. Lowering the trophic status of surface waters is expected to increase resilience against predicted global warming and therewith reduce problematic cyanobacterial blooms. Cost-efficient mitigation calls for a tailor made benefit oriented restoration plan, building on an arsenal of restoration techniques, combined with innovative techniques (e.g. geo-engineering techniques).

Qing will be primarily based in the Netherlands Institute of Ecology, Netherlands, supervised by Dr Lisette de Senerpont Domis, and will be co-supervised by and spend study time with Dr Miquel Lurling, Wageningen University, and Dr. Rafa Marcé, Catalan Institute for Water Research, Spain. The PhD will be awarded by Wageningen University.

More information about this project can be found: https://www.mantel-itn.org/

Using system diagnosis to assess pressures on aquatic systems

Pharmaceuticals are therapeutic agents contaminating aquatic systems and hence included in the Water Framework Directive’s watch list of Contaminants of Emerging Concern. High global consumption of pharmaceuticals has led to their increased occurrence in aquatic systems. As they are designed to be therapeutically active at ng/L to μg/L concentrations, pharmaceuticals can affect non-target organisms in aquatic system exhibiting sub-lethal effects. Sub-lethal effects caused by pharmaceuticals can be direct when there are similarities in the mode of action. Indirect effects triggered by pharmaceuticals can be density-mediated and/or trait-mediated including the once caused by the disruption and/or mimicking of infochemicals involved in chemical communication between organisms.
In this project, we explore the sub-lethal effects of pharmaceuticals on aquatic food web functioning. Firstly, by understanding the impact of sub-lethal concentrations of pharmaceuticals on trophic interactions. Secondly, we assess the significance of these sub-lethal effects on aquatic food web functioning. Therapeutic drugs with high global occurrence, environmental relevance and persistence are used for all the experiments. The observations and findings of this project will inform the water managers about the significance of considering the sub-lethal effects of environmental concentrations of pharmaceuticals on aquatic ecosystems while determining their environmental risk limits.

Over a million Dutch citizens use psychopharmaca like anti-depressants and anti-psychotics, which enter surface waters after use. Designed to affect the nervous system, psychopharmaca will mimic so-called infochemicals, and influence communication and behaviour of organisms. Thereby psychopharmaca potentially disrupt ecosystem structure and functioning. Their expected increased use challenges the management of water quality. This project focuses on possible reductions of emissions and effects. We aim at possibilities to improve regulations, to design more friendly alternatives, understand ecosystem effects and mitigate effects by water treatment technologies and nature-based solutions. Psychopharmac'eau is a collaborative project between NIOO-KNAW, University of Amsterdam(UvA) and Wageningen University and Research(WUR).

Though shallow surface waters are known GHG emission hotspots, the quantification of its GHG emission levels is hampered by the lack of accurate measurements and sound spatial extrapolation methods. As a consequence, climate-smart decision-support tools for surface water management cannot be developed. This is an important caveat, because there is a large potential to reduce GHG emissions from shallow surface waters. The project will tackle this problem by providing a first evidence-based estimate of GHG emissions of shallow inland waters in the Netherlands, and by identifying measures to reduce GHG emission and increase carbon storage in surface waters. These data will be used to develop and validate climate-smart management tools that can be applied by the water management stakeholders involved in the project. DIGS will provide means that will directly contribute to the principal priority of the Dutch government to combat climate change: reduction of Netherlands’ GHG emissions by 49% in 2030, compared to 1990 levels. DIGS is funded by the Open Technology Program of NWO and has a term of four years starting in 2021.

Plastics have been widely used in everyday life since the 1950s, mainly because they are cheap and have a long durability. Plastics have a long degradation period, remaining in the environment for hundreds and thousands of years. During this period, plastics break down, due to photodegradation, abrasion, hydrolysis and biodegradation into smaller particles called microplastics (< 5 mm). Until now, much attention has been paid to quantify microplastics in the oceans. However, there are indications that microplastics are accumulating in the food web not only in the oceans, but also in fresh water systems.

Because microplastics shield the light, they can cause growth inhibition and decrease photosynthesis activity of freshwater microalgae species. In addition, zooplankton and benthic invertebrates accumulate microplastics in their digestive tracts leading to a reduced feeding activity, and in some cases reduced survival and fecundity. The zooplankton benthic invertebrates are in turn consumed by fish. In this way, microplastics can affect the entire food web, including higher trophic levels such as birds and humans.

The objective of this research project is to demonstrate the effect of microplastics on trophic interaction and scale up to food web effects in large indoor mesocosms. Linking small-scale laboratory studies to large-scale experiments and exploring more environmentally relevant scenarios will provide critical knowledge on the effects of microplastics at the community and ecological level, essential for further risk assessment.

Nature's Integration in Cities' Hydrologies, Ecologies and Societies (NICHES)