Welcome toHydroTalks, the new podcast series of the EGU HS division. Every month, we interview experts about the advancements, challenges, and opportunities in the field of hydrology.
As our first guest, we were pleased to interview Dr. Stefan Krause, a Professor of Ecohydrology and Biogeochemistry at the University of Birmingham. His research explores the interconnectedness of groundwater and surface water, water pollution, and ecosystem resilience.
Check out the podcast below, or read the interview summary in this blog!
What are key concepts in ecohydrology and biogeochemistry that all researchers should be aware of, but about which there is not a lot of information out there?
For hydrologists, it is key to understand where water flows and how long it takes since it controls a lot of non-physical processes like the behaviour of a lot of the contaminants and biogeochemistry.
We often take a very classic view and I want to challenge that. Hydrological fluxes control reaction rates and that impacts environmental conditions like carbon and nutrient availability in a habitat. Flow velocity has a significant impact on aquatic animals and plants. We are also trying to see how ecology is affecting hydrology and biogeochemistry. Many species like non-biting midges larvae would pump huge amounts of water and larger mammals like beavers would act as ecosystem engineers. So I think we need to see these interactions in a more circular way.
Why should the general public be interested in this feedback between ecosystems and hydrological processes?
Because it affects us all. Rising global demand for water concerns us all. But at our doorsteps, we are affected by the quantity and quality of our waters. Water pollution is an issue that affects us all the time. A very bad example is Untreated sewage releases in Britain have been affecting bathing water quality, and there are economic impacts on oyster production, fish stocks.
Do you think the policymakers are paying any enough attention to the ecohydrological feedback loop?
It varies a lot between countries. We are very happy that as a community we are finding a stronger voice in events like the UN Water Conference and International Association of Hydrological Sciences scientific decades. I think that’s where we can hopefully bundle our individual voices for actions and articulate what needs to be done.
How do emerging contaminants put pressures on the natural biogeochemical cycles?
The traditional view of looking into individual pressures and their impacts on biogeochemical cycles is not necessarily adequate anymore. Quite often due to the interaction of multiple stressors so-called tipping points can be reached much earlier. For instance, we can look into how toxicity of contaminants like engineered nanoparticles or microplastics is changing as water temperature also reaches a certain critical threshold and how ecosystems are interacting with other stressors.
What are engineered nano-particles?
There’s a broad range of nanoparticles that get engineered. Like titanium dioxide, for instance for sun-blocker creams, silver nanoparticles that are used in textiles, like reducing the smell of running socks. Nano-technology follows principles of safety by design standards, but that involves looking into how they behave in the environment. My current focus is on microplastics, and their impacts.
How are the microplastics getting into groundwater systems?
That is not very well established. We only recently were able to reveal that at the interface between groundwater and surface water, hyporheic exchange pumps large amounts of microplastics directly into stream bed environments. Also there is potential for transport particularly in fractured and karstic rocks.
Is there any remedy and recommendation for this problem?
The one that gets a lot of media attention are clean up operations.
I think we need to tackle the problem where we start emitting contaminants into the environment. There’s a lot of research into bioplastics and biodegradable solutions. I personally think that reduced consumption and reuse is a promising path forward.
What have been some breakthroughs in your field over the past decade and what questions should young hydrologists focus on?
I think a really big innovation over the last decade has been in-situ monitoring to monitor the hot moments or the hotspots of pollutants in a much better way. In the future I think that data sciences and AI can help us to better utilise big data, and also optimise these observations for being more economic.
I think focusing on the environmental fate and transport of many of the emerging contaminants is a potential field. A more general piece of advice is generous with ideas. I was able to have fantastic collaborations following that advice.
Listen to the full HydroTalk podcast for more insights from Prof. Krause, and stay tuned for upcoming episodes exploring the frontiers of hydrology and environmental science.
