Change on the horizon: Emerging science in land, air and water

Dr Monica Rivas Casado, Reader in Environmental Systems Engineering

The uptake of emerging and disruptive technologies has significantly increased over the last decade across the water sector. Robotics and autonomous systems, as well as novel data science techniques (big data), are changing the ways we inform management decisions.

The deployment of these technologies embraces a wide range of applications, from the effective monitoring of greenhouse emissions with drones in wastewater treatment plants to the automated identification of surface water flood impact using artificial intelligence. This technology-data driven revolution has empowered organisations to collect, process and interpret more data than ever before.

There is an opportunity to unite efforts across organisations to collectively share their data and analytical tools to manage risk, plan ahead, and work towards a better future for the environment. A standardised approach to data collection, processing and interpretation would act as a conduit to maximise shared use of data and processing tools within the sector. The opportunity exists to devise a fit-for-purpose systems engineering approach to map data and technological interconnections across organisations. The combined use of both standardised approaches and systems engineering solutions would provide transformative change to the sector.

Sarah Horrocks, Head of Air Quality and Emissions

“Ecological damage caused by nitrogen deposition is now considered to be one of the most widespread and significant atmospheric pollution effects on the natural environment” (Natural England).

Nearly three quarters of England’s most important designated sites are sensitive to nitrogen (N) pollution. Critical loads for N deposition (Ndep) are exceeded in the majority of designated habitats, which affects their ability to reach favourable conservation status or condition.  Reductions in nitrogen oxides (NOx) and ammonia (NH3) emissions are therefore required to protect these sites.  

IAQM Committee members’ work for the JNCC Nitrogen Futures project found that actions and targets such as those set out in the Clean Air Strategy and National Air Pollution Control Programme, will improve air quality for biodiversity (as well as human health) but the improvements are not fully protective of UK ecosystems, especially in areas with high atmospheric nitrogen input to habitats.

In recent years some residential and agricultural developments have been rejected due to the European Court of Justice (ECJ)’s 2018 judgement in the ‘Dutch Nitrogen’ case under the Habitats Directive. The ECJ concluded that there needs to be certainty at the time of the assessment (“beyond reasonable scientific doubt”) of the benefits of mitigation measures. This includes autonomous measures, i.e. those not directly related to the plan or project being considered. The need for ‘certainty’, and the legislation’s requirement for a precautionary approach, has led to some competent authorities refusing planning consent. 

To help developers demonstrate their proposals will cause no overall increase in nutrient pollution at designated sites a nutrient neutrality (NN) approach for the mitigation of impacts on watercourses has been rolled out. The aim is to enable new development to take place through the mitigation or off-setting of additional emissions, most specifically phosphorous releases, as an interim solution whilst sites are restored to favourable condition. Actions to mitigate impacts include measures on or off-site, or to use a system of nutrient credits via a nutrient trading scheme e.g. land taken out of agricultural use and converted to wetlands and woodlands.  

A similar system for mitigating and off-setting air emissions from new development may help fulfil housing needs while reducing emissions to bring nitrogen sensitive sites closer to achieving their critical levels and loads.  Ammonia emissions would need to be a key focus for such a scheme as they are not showing as strong a rate of decline as combustion emissions such as NOx. Agriculture accounted for 87 per cent of total ammonia emissions in 2021 and this was the main contributor to the increase in emissions between 2013 and 2017. There may, however, be political and economic resistance to such an approach, not least because of the multiple pressures that agricultural land is coming under (including nature based solutions) and a full appraisal accounting for all factors will be needed.  

Jonathan Atkinson, Technical Director

At the recent MPs inquiry on soil health, soil was described as the Cinderella of the environment family, finally emerging from the kitchen shadows to show its wonderful, complex, and vitally important face among the step family of air, land and water. Yes, soil is part of land perhaps, but as always in the past with groundwater in the water family, underground is out of sight, and for too long land has been in the spotlight with regards to above ground biodiversity - a great thing of course - but all living things above ground depend on soil. 

With the Environmental Improvement Plan (EIP) giving soil its more deserved profile in the mix of land use, food security, sustainable development and resource management, soil scientists can take heart that their advice is finally being listened to. But the work is not over. We must now urgently move forward with actions to enable our soils to help society address its most severe challenges; food security, climate change, biodiversity loss, natural flood management, sustainable development and resource management. As the EIP points out soils are a resource not a waste to be thrown away or degraded carelessly. They are the basis of all living things! 

An overarching soils framework or strategy is needed to drive the change we need, to urgently enable soils across all sectors to help meet the very real challenges we face as a society in the next 10 years, here in the UK and around the world. The science is there, the tools are there and developing further, what is needed now is a framework to set soils on the same level as air, land and water, all issues we urgently need government and all sectors to address robustly. Let the soil scientists out of the labs and out into the field and help farmers, developers, resource managers, housing developers, infrastructure managers etc. to give soil the spotlight it deserves. The Society for Environment recently published its Ten Principles of Good Soils and Stones Management, that sets the scene nicely.

Soil is the Cinderella star of the Prince’s Ball, now our government needs be a real Fairy Godmother and provide the frock (soil resource management framework), dancing shoes (Environmental Land Management Scheme) and glittering carriage (Soil Health Action Plan for England) to get her to the ball in time. Our planet hasn’t got much time left to sort this out!

Seamus Lefroy-Brooks, Lead LBHGEO Ground Engineering

Although a greater focus on soil health is to be applauded, it needs to be clear that practice informed by soil science cannot be limited to agricultural soils but must be applied across the land condition sector. 

The value of natural soil is not yet realised by the development and construction sector and it is still commonly discarded as waste. On sites that have been earmarked for construction and development we need to improve the identification and segregation of:

• those soils that are in a natural “greenfield” state and have not been subject to past human interference (other than agriculture);
• those “brownfield” soils that have been disturbed and contaminated. 

Increased knowledge in this area will be an important aspect of influencing practice so that clean natural soils are not inadvertently discarded or mixed with other materials and thus their function as a vital resource to sustain ecosystems is not lost. 

We also need to make sure that the tools we have to support better environmental outcomes are supported by robust science. For example, the Biodiversity Net Gain Metric is currently based upon surface plant habitats without specific consideration of deeper soil health. This could be problematic as, for example, a historic landfills site may be valued as a plant habitat without accounting for the risk of harm presented by the contaminated land below. 

This presents some key areas that will need further research: 

• How can we measure soil health? 
• Should habitat types/values only be applied following initial assessments on soil health and contamination?