National Character Area 39

Humberhead Levels - Natural Capital and Key Ecosystem Services

Introduction

The Humberhead Levels NCA provides a wide range of benefits to society. Each is derived from the attributes and processes (both natural and cultural features) within the area. These benefits are known collectively as ‘ecosystem services’. The predominant services are summarised below. Further information on ecosystem services provided in the Humberhead Levels NCA is contained in the ‘Analysis’ section of this website.

Note: The natural capital in this NCA is mapped below. This displays more recent national and publicly available data sets as used within Natural England’s 2020 Natural Capital Atlas Profiles.

The predominant ecosystem services in this NCA are also summarised below. The text contained in this section is based on the previous NCA profiles in 2014, and so is not entirely current. Further information on ecosystem services provided in the North Northumberland Coastal Plain NCA is contained in the Analysis: Ecosystem Services page of this website.

What is Natural Capital?

Natural capital means “the elements of nature that directly or indirectly produce value to people, including ecosystems, species, freshwater, land, minerals, the air and oceans, as well as natural processes and functions” (Natural Capital Committee, 2017).

It is helpful to consider natural capital in the form of a logic chain that represents the links between ecosystem assets, services, benefits and value to people. The figure below displays that logic chain. The quantity and quality of ecosystem assets (woodland, bogs, etc) support different types of ecosystem services, such as carbon sequestration or water filtration. These ecosystem services then provide different benefits to society, providing value for people. The figure also shows how management interventions, as well as pressures and drivers of change, influence this chain. Other capital inputs are also often needed for people to obtain the benefits from ecosystem services (a simple example is the processing of trees to produce wood products).

As an example, an area of woodland (ecosystem asset) may reduce air pollution created by traffic on a nearby road. This woodland is therefore improving air quality (ecosystem service) in the local area which results in cleaner air and improved health in the adjacent residential street (benefit). This cleaner air has a value because we know it impacts the health and wellbeing of communities.

Sometimes for ease of understanding, economic framing is used to give these benefits a monetary value. The figure below shows how natural capital assets support the provision of ecosystem services, benefits and value. The roots of the tree show how aspects of asset quality are critical to the provision of ecosystem services. The roots also show that geodiversity underpins the ecosystem assets and therefore the ecosystem services and benefits they can provide. It is important to remember that this diagram, and natural capital frameworks more generally, are a simplification of how nature works in practice.

Natural Capital within this NCA

In 2018, Natural England published ‘Natural Capital Indicators: for defining and measuring change in natural capital’ (Lusardi et al., 2018). This report identified key properties of the natural environment vital for the long-term sustainability of benefits, which can act as indicators of change.

These indicators are designed to inform our understanding of the state of our natural assets. The indicators highlight the importance of our natural assets for delivering which ecosystem service and the benefits they provide for society. The indicators and datasets identified in Natural England’s Natural Capital Indicators Project provide the foundation for the Natural Capital Atlas Profiles.

Natural England’s Natural Capital Atlas Profiles provide an “off the shelf” natural capital evidence base for each county or city region. They have a wide variety of uses with more information in the How to Start Using Your Natural Capital Atlas.

The Natural Capital indicators are presented on the map below by broad asset theme, displaying the natural capital within the NCA.

It is noted that not all indicators listed within the Natural Capital Atlas Profiles are included within the map as data is not yet available to measure them. Refer to the “Indicator Gaps and Limitations” of the Natural Capital Atlas Profiles for further information.

Note that numbers and figures in the body of the text are based on the 2014 profiles, unless otherwise stated.

Provisioning services (food, fibre and water supply)

Food provision: This is one of the most productive agricultural areas in the country, with 10 per cent of the land classified as Grade 1, 33 per cent as Grade 2, while a further 41 per cent is Grade 3.

Biomass energy: The existing woodland cover of 5.4 per cent offers limited potential for the provision of biomass through bringing unmanaged woodland under management. However, there is potential for increasing the area of biomass crops such as miscanthus; the extent of this will be determined by the market led decisions of the many local power stations.

Water availability: The availability of water is likely to become more critical with the anticipated effects of climate change such as summer droughts. The western half of the NCA overlays the major Sherwood Sandstone Aquifer, which provides a strategically important source of water for domestic use as well as industry and agriculture, and needs to be replenished. Levels of abstraction of water from the rivers need to be managed carefully, and the demands of summer irrigation of crops may lead to an increase in construction of farm reservoirs. For information regarding the current state of water availability within this NCA, refer to the Environment Agency (Abstraction Licensing Strategy).

Regulating services (water purification, air quality maintenance and climate regulation)

Climate regulation: Significant climate regulation is offered by the carbon captured in the areas of peat with their high carbon content soils. An expansion of wetland habitats and permanent grasslands would also assist with building up soil carbon and reducing the use of artificial fertilisers.

Regulating soil erosion: The continued cultivation of peat soils, with the lowering of water table levels, is exacerbating the process of drying out and oxidisation of the peat, thus making them vulnerable to both wind and water erosion, while the organic content of the sandy soils is low. Agricultural practices should address protecting the soil resource from erosion by maintaining cover and increasing organic content.

Regulating coastal flooding and erosion: Some central stretches of this NCA are close to sea-level and are maintained as agricultural land by pumping. The Humber Estuary drains one fifth of the area of England and much of the area is at risk from fluvial flooding from rivers that drain into the Levels from surrounding higher ground. The risk is exacerbated by combinations of high rainfall within the catchment of the estuary, high tides, on-shore winds and low atmospheric pressure. Extensive areas are dependent upon flood defences including land in the floodplain of the rivers Ouse and Aire, while along the Humber Estuary some significant managed realignment is being carried out to increase the capacity of the river. Opportunities exist for extending flood storage areas and managed realignment of the estuary banks, with consequent creation of wetland and inter-tidal habitats. For information regarding current shoreline management within this NCA, refer to the Environment Agency (Shoreline management plans).

Cultural services (inspiration, education and wellbeing)

Sense of place/inspiration: A sense of place is provided by the flat, low lying and large scale farmed landscape crossed by major rivers and dykes. The big open skies and long views can be inspirational, as can the chances to see large numbers of birds, especially overwintering waders. The subtle variations within the area give rise to distinct local areas such as the quiet marshes and meadows of the Lower Derwent Valley and the heathlands of Skipwith and Strensall commons. The lowland peat bogs in particularly provide a sense of remoteness and wildness, unusual within such a cultivated landscape.

Sense of history: A sense of history is associated with the management of water, evidenced by old river courses such as the Don, historic ditches, berms, dykes, canals, bridges, disused windmills, water towers and canals, reflecting both the reclamation of the area for cultivation, and the importance of the waterways as major transport routes. There are distinctly different historic landscapes such as the warps near Goole, the cables near Thorne, and the enclosed agricultural landscape around Fishlake and Sykehouse. In particular there are the remnant medieval open field patterns of the Isle of Axholme, one of the largest examples of open field strip cultivation, which is associated with Haxey and Epworth Turbaries, where traditional peat cutting rights were exercised.

Tranquillity: Although the area has experienced a significant decline in tranquillity since the 1960s, there are still significant areas of tranquillity at Thorne and Hatfield Moors, the Lower Derwent Valley and around Fishlake and Sykehouse.

Recreation: There are recreational opportunities associated with the National Nature Reserves at Thorne and Hatfield Moors, flagship reserves for providing access, while the paths along dykes and canalised watercourses provide ways of experiencing the remote open spaces.

Biodiversity: While the predominant land use is agriculture, there are sites of international and national importance, including 2 Ramsar sites, 3 Special Protection Areas, 6 Special Areas of Conservation and 40 Sites of Special Scientific Interest, as well as 577 local wildlife sites. The lowland raised mires of the Humberhead Peatlands, the lowland heathland at Skipwith Common and the Lower Derwent Valley are all National Nature Reserves, while the Lower Derwent Valley and Humber Estuary are both Ramsar sites.