Written Evidence submitted by Norwich Research Park (SH0045)


This submission has been produced by scientists from the Norwich Research Park; one of the largest single-site concentrations of research in agri-food, genomics and health in Europe. The Park is a partnership between the University of East Anglia (UEA), the Norfolk and Norwich University Hospitals NHS Foundation Trusts, and four independent world-leading research institutes, namely, the John Innes Centre (JIC), Quadram Institute (QI), the Earlham Institute (EI) and The Sainsbury Laboratory (TSL).

After London, Cambridge and Oxford, Norwich is ranked 6th in the UK for the number of most highly cited scientists. The Research Excellence Framework (REF) 2021 underlined UEA’s (and it’s co-assessed Park partners: QI, EI, TSL) pre-eminence as the number one Research Unit in Agriculture, Food and Veterinary Science in the UK. 

The Park hosts more than 70 research groups working on soil health relevant topics. These include groups undertaking research from molecular to catchments scales in the following: soil degradation/formation,

Currently the Park’s microbiology research is being reviewed and the findings of this review will be shared with UKRI for approval shortly. We will look to share the strategic outcomes of this review to further inform the inquiry once available.

1. What are the challenges in gathering data to measure soil health and how can these barriers be overcome? 

It is important to distinguish abiotic (everything physical and chemical, like sand/silt/clay proportions, elements and molecules) from biotic (everything living, such as earthworms and microscopic bacteria/fungi) factors that underly our definition of “soil health”. Both factors are important components of a healthy, sustainable soil.

To consider health using purely biotic parameters as a measure of “health” is fundamentally flawed. One cannot expect the same values of a given biotic measure if, for example, soil texture, soil pH, levels of organic matter and/or nutrients vary from field to field. Beyond these intrinsic relationships that influence biotic outcomes, externalities further complicate matters. Climate is critical to determining the values of health ultimately measured: a warm dry soil in the East of England will support a different portfolio of health parameter values when compared to a cold damp wet soil in the Northwest of Scotland. The seasons exert their influence too. At times, soil will saturate following heavy rain; heavy clay land might remain waterlogged for an extended period while light sandy land will return to a drier state much more quickly. The chemistry and biology of the soil will ebb and flow with these shifting conditions.

Thus, there will never be a one size fits all measurement of soil health. This said, there is potential for an assessment system where benchmarked “optimal” values of a given measure and/or set of indicators can be evaluated and holistic health can be determined within a constrained boundary of reasonable expectations.

The soil contains thousands of interacting microorganisms (the soil microbiome) that carry out a range of vital agricultural services. The roots of plants are hotspots for microbial life because of the availability of plant-derived root exudates. Plants secrete about a fifth of all of the CO2 they fix from the atmosphere back into the soil and this flow of carbon into the soil leads to a huge increase in microbial life directly surrounding plant roots. This community has profound effects on plant health, disease, and productivity.

These plant-associated microbes provide important nutrients and minerals to crops (e.g. fixing nitrogen from the air, solubilising inorganic phosphate and other micronutrients), they suppress plant diseases, break down organic matter, clean up soil pollution and promote plant growth. There is an emerging consensus that healthy soil not only needs to contain a good balance of nutrients, soil structure and organic matter, but also needs to have a healthy microbiome. The composition of the soil microbiome is highly important for its effectiveness in maintaining and/or enhancing soil health. While this is a relatively new field of science and there is still a lot to learn, we believe that targeted manipulation of the soil microbiome holds tremendous promise for the development of sustainable agricultural practices.

What to measure, and how to measure it?

We have a proficient understanding of important abiotic factors for soil health, but the biotic factors are much less explored and only recent technological developments (sequencing technology) have enabled efficient exploration of the microbes important in soil health.

Our current understanding is that microbes (fungi + bacteria + archaea + protozoa) living associated to plant roots are incredibly important in providing nutrients to plants and protection from pathogens. However, we do not know what the best composition and ratios of these microbes are to truly define “healthy soil”. Similarly, the trophic levels that exist above the soil microbiome are shaped by it and, like the microbiome, influenced by the prevailing soil condition. It is estimated that there are 100,000 different types of organisms living in soil with new species being discovered all the time. Coleman and Wall (2019; Chapter 5, Soil Fauna: Occurrence, Biodiversity, and Roles in Ecosystem Function, in Advances in Ecological Research, 61, (163-184) provides an excellent synopsis.

Even within bioclimatic regimes the biotic assemblages vary during the year. Thus, a soil health assessment made in January at one site will not be comparable to another made in August at another site.

To establish profiles indicative of good soil health, systematic cataloguing of the bacterial/fungal and faunal components of UK soils is needed. These catalogues should establish the defined ranges of taxa that should be present in specific soil types, at specific times and across different geoclimatic regimes.  As emphasised above, these assessments need to acknowledge variations driven by the seasons, climatic regime and must be tethered to the abiotic factors that underpin the microbiome boundary.

2. Do current regulations ensure that all landowners/land managers maintain and/or improve soil health? If not, how should they be improved? 3. What are the threats and opportunities for soil health as ELMs are introduced? 

Building soil carbon is the circuit-breaker to check and reverse damage done to soil natural capital. Not only will soil recarbonisation efforts sequester carbon, but they will also “nourish” the soil, improve its health and optimise its capacity to deliver its ecosystem services. 

Beyond carbon storage, soil carbon is the fuel that regulates soil-microbiomes, soil ecosystems and soil ecosystem services. Yet the shaping influence of different pools of carbon on soil ecology remains poorly understood.

While one might, for example, build soil carbon quickly with recalcitrant biochars, this carbon will not sustain the life in the soil in of itself. Indeed, evidence shows biochar carbon, because it is so recalcitrant, can prime the degradation of in situ soil carbon. So, on one hand, there is an intervention that could build a robust carbon credit (biochar supported long-term carbon storage), on the other, the same intervention might stimulate unwanted CO2 emissions from soil and diminish the “nutrition” that underpins soil life. The Government must recognise in regulations and requirements that not all soil carbon is equal and acknowledge the assessment of both permanent and labile carbon stocks/assets.

The UK is developing a Farmland Soil Carbon Code (FSCC) to inform and guide soil carbon management to complement already established Woodland and Peatland Carbon Codes. The FSCC will shape changes on a farm level and at landscape dimensions. Central to success of the Code will be robustly defining long-term “permanent” soil carbon storage.

While the current state of the art technologies can measure soil carbon content, this is not the same as knowing how long that carbon will persist. While we have some grasp on how interventions (e.g. cover-cropping, minimum tillage, etc.) can increase soil carbon we cannot accurately predict how long newly sequestered carbon will persist for, nor how different UK soil types and climate influence carbon storage permanence. If we are to embrace soil/nature-based approaches to carbon sequestration it is essential that we understand the feedbacks, synergies and antagonisms associated with soil recarbonisation. 

Nationally determined contributions to achieve climate targets, as well as private sector net zero plans, frequently place considerable hopes in soil-carbon-based offsets. However, such aspirations often ignore the issues of reversibility, impermanence, and limited capacity of soil carbon sequestration. Hence, a comprehensive understanding of how soil carbon balances respond to land management practices, agricultural inputs, and weather conditions over a medium- to long-term timeframe is necessary to inform policy and practice.

Offsets are becoming increasingly commonplace, with biodiversity offsetting now mandatory for new developments. Yet, the industry and regulators needed to support this economy are immature with the essential skills largely absent on the ground. Granular understanding of carbon stocks and flows also needs to be translated to provide a realistic grounding for policy and the design of carbon markets. This requires a better discourse between soil scientists, economists and policy experts, to overcome the limits of each discipline. The challenge for new soil carbon policy is to appreciate the dual role of different sorts of soil carbon and financially reward both. It is possible to assess different carbon pools, but the UK Farmland Soil Carbon Code does not recognise this. 

Similarly, other ecosystem service assets – biodiversity net-gain, nutrient retention, flood mitigation – delivered by soils need more comprehensive understanding. Expertise is needed to develop effective and transformative natural capital pricing through market or policy tools.

When exploring land management, we must consider the role of tenant farmers. Will a tenant farmer be motivated to manage soil sustainably, sequester carbon, improve soil health and optimise the delivery of soil goods and services if they have no legal access to these goods and the revenue they might command? Further, these assets may not “mature” within the envelope of a tenancy - so why work towards creating these assets when only the landlord has title over them? This is not a trivial matter. Around a third of land farmed under tenancy and these issues of entitlement require government attention if improved soil health is to be delivered to capacity and with equity.

Inherent to this is the establishment and governance of the emerging ecosystem service markets including carbon-credits, nutrient-credits and biodiversity credits The shift to this new economy is underway, but we currently lack workplace skills to effectively manage this paradigm shift risking absolute market failure if not addressed.

4.      What changes do we need to see in the wider food and agriculture sector to encourage better soil management and how can the Government support this transition? 

The UK agri-food system accounts for almost a quarter of greenhouse gas emissions and almost half of these come from the agricultural sector although emissions from agriculture are estimated by the Government to have broadly flatlined since 2008.  Regardless, the Climate Change Committee’s Sixth Carbon Budget assumes significant change in the agri-food system up to 2050 to meet the UK’s net zero target.  The transition pathway it advocates involves maintaining food production at current levels, reducing the amount of land farmed by almost a quarter, and markedly reducing emissions from remaining farming practices.  Significant spared land will be required to plant almost a million hectares of trees by 2050, raising UK forest cover from 13 per cent to approaching 20 per cent.  Such significant land use change is also likely to require an acceleration of dietary change, including reduced consumption of ruminant meats and dairy.  The net zero challenge is increasingly framing the development of the agri-food system in the UK and internationally.  Similarly, other countries such as Ireland, Netherlands and New Zealand are developing measures including taxes, levies and livestock reduction targets to reduce emissions from their livestock sectors.  Net emissions reduction must become the key strategic priority steering the Government’s approach to the agri-food system and rural land management.  Soil management will need to be a key component of this approach but will need to be accompanied by appropriate measures to: i) encourage dietary change; ii) free up land from agricultural production for other vital purposes, including sequestration; and iii) reduce net emissions from production practices on remaining land.

We assert that advances in sustainable agriculture could be made in three non-exclusive fields. The first of these is the development of smart land management practices that promote healthy soil microbiomes or shape the microbiome towards a desired agricultural goal. Approaches in this field are already widely used, for example in the adoption of no-till agriculture or successive monocropping of cereals to develop disease suppressive soil. That said, there is still room for substantial improvement in this area as our understanding grows on the relationship between agricultural practice and the soil microbiome.

The second major area for sustainable agricultural advances is in the development and application of effective bioactive agents. These products are typically composed of different combinations of soil dwelling microorganisms with agriculturally useful properties, such as the ability to suppress pathogens or fertilise soils. Again, these products are already in use, for example the application of the bacteria Rhizobium to boost nitrogen fixation in legume crops. Issues with reliability and efficiency currently limit the market for these products. However, the withdrawal of many pesticides on ecological/safety grounds, alongside a rapidly advancing knowledge of these microbes and their activities mean that there is potential for significant growth in this area.

The final field with potential for future growth in sustainable agriculture is in the breeding of crops that recruit beneficial microbes and sustain their own healthy microbiome; and by extension reduce the need for inputs of fertilisers, fungicides and pesticides. While modern breeding has massively increased yield per hectare for many important crops, very little attention has been given to breeding traits related to soil health. This is a very new field, but exciting research, including in the UK, supports the existence of breedable plant traits that could improve the relationship that crop plants have with their soil microbiome. Soil health is also important for supplying crops with a balanced and even supply of nutrients. Roots can input carbon to the soil to sustain the food web diversity that exists below ground. There are huge opportunities to improve below-ground diversity by growing a mix of crops that can promote soil health.

This could potentially lead to improved varieties that take less from the soil and maintain a healthy soil microbiome, while being less prone to soil diseases or environmental stress.  The breeding industry needs to be incentivised to deliver these goods and the policy framework across this area must be supportive of the adoption of novel techniques and technologies to meet these complex challenges. We are therefore supportive of the steps taken to enable this through the Genetic Technology (Precision Breeding) Bill. Advanced technologies such as gene editing and genetic modification have already enabled the development of disease resistant plants that will require significantly less fungicides. Such varieties will be more beneficial to soil health by lowering the negative impacts of these chemicals on soil microbiomes, and reducing occurrences of soil compaction associated with the tractors spraying these compounds. The benefits of this could be further enabled with support from retailers and buyers to encourage a more optimal pattern of land use in addition to increasing uptake for healthy and sustainable foods. 

Soil probiotics – defined cocktails of beneficial microbes to plants – could be used instead of chemically based fertilizers. To maintain and cultivate a locally present microbiome, such probiotic cocktails would ideally only be used in conjunction with monitoring the existing soil microbiome and intervening only if an adjustment would be required. Currently sequencing prices are decreasing and as a consequence monitoring of (microbial, perhaps with further development mesofauna also) soil health through DNA sequencing is thus becoming more feasible.

Given the increasing Government interest in soil per se, the services and goods it can deliver when its health is optimised and the increased accessibility to soil assessment platforms there is timely opportunity to define a Soil Health Framework. With the growing, albeit cautious, appetite of farmers and landowners to explore natural capital markets, and the prospect of catapulting an emerging natural capital financial market to drive economic growth, the Government has responsibilities to ensure soil health, and its monetarisation, is credible. Key to this will be the establishment of standards, verification procedures and governance systems.


February 2023