Spains Hall Estate

Introduction

Spains Hall Estate (SHE), a farm in south-east England, have established a completely new model of farming including forest restoration, agroforestry, biodiversity-friendly farming methods and farming for ecosystem services, including natural flood management.  It is a superb example of how land can provide both high value crops for the market and a range of ecosystem services as public goods .  Policysupport.org (King's College London and AmbioTEK) have worked with Spains Hall Estate since 2019, monitoring and modelling the meteorological, hydrological and biodiversity baseline and helping understand landscape processes and the environmental benefits of the farming interventions made.

Sustainable farming

Spain's Hall Estate is actively engaged in several environmental initiatives:​

Natural Flood Management: The estate employs natural flood management techniques, such as use of leaky debris dams, beaver re-introduction and reforestation, to reduce flood risks. These methods enhance water retention and slow runoff, protecting downstream communities. 

Biodiversity Net Gain: By restoring habitats (e.g. woodland and wet woodland) and incorporating nature into farming systems (e.g. herbal leys), Spain's Hall Estate contributes to biodiversity net gain, including the generation of some 500 BNG credits. 

Countryside Stewardship: Participating in Countryside Stewardship schemes, the estate adopts sustainable farming practices, hedgerow planting, and field margin management to enhance wildlife habitats. ​

Agroforestry: The estate is developing the largest agroforestry project in Europe. This farming system is more resilient than arable to climate drying, provides high value nut crops, improves soil health, increases carbon sequestration, provides shade for other crops and enhances overall farm resilience.

Agriculture: The estate employs nature-friendly agricultural techniques for more sustainable food production, environmental conservation and nature recovery.

Ongoing research

Our research at Spains Hall Estate has been ongoing since 2019, funded by H2020 NAIAD and H2020 ReSET and involves the development of environmental intelligence for understanding strategy and effectiveness assessment for nature-based solutions.  This involves intensive digital monitoring using www.FreeStation.org open source monitoring systems and detailed spatial modelling using WaterWorld and Co$tingNature.  The current network of monitoring stations is shown in the map below.  Activities include:

• Monitoring streams and ditches to better understand the source areas for water and the dynamics of streamflow in relation to  rainfall, land cover and soil properties;

• Monitoring the impact of natural flood management interventions — including leaky debris dams and beaver re-introduction — on flood peaks, dry season flows and water quality;

• Monitoring of weather and its variability in time and space across the estate, including measurement of novel metrics such as instantaneous rainfall rates;

• Monitoring of soil moisture dynamics across the estate and the impact of different farming practices on soil moisture.  Monitoring of moisture dynamics in agroforestry systems and the potential for drought impacts of tree growth;

• Monitoring of biophony using acoustic monitoring methods, for better understanding spatio-temporal variation of audio-ecological surrogates for biodiversity.  

• Modelling the effectiveness of natural flood management (NFM) interventions in reducing flood peaks, with WaterWorld/local

• Mapping the ecosystem services provided by SHE using Co$tingNature/local

Data

We have >26 long-term data loggers in place, making SHE one of the most intensively monitored farms in the world. These dataloggers are our own www.freestation.org designs and record data every 10 mins to characterise meteorology, hydrology and audio-ecology at SHE.  As developers of the FreeStation technology, we have also tested and perfected a number of new FreeStation prototypes at SHE.  We have also developed an instance of Co$tingNature/local and WaterWorld/local at 10m spatial resolution for SHE. Co$tingNature/local maps nine ecosystem services (wildlife services to cropland - pollination and pest control; grazing and fodder services; carbon storage and sequestration, fuelwood, water pollution dilution; natural flood storage; water resource provision; urban cooling and soil erosion mitigation) and helps to understand nature's benefits to people.  Example data are shown below.

Results so far

To date, our research as part of the H2020 NAIAD and H2020 ReSET projects has focused on the development of low-cost, open source environmental sensors, dataloggers and networks of sensors and their application to environmental intelligence.  Having developed a reliable, accurate, maintainable and integrated network of sensors our current work is focused on using data from the network to better understand the impacts of interventions at SHE on biodiversity and ecosystem services.  With the data collected so far, we have shown that:

• Most (~75%) of the flow to Finchingfield originates in the main Finchingfield Brook with ~11% from the beaver stream and some ~14% from the East Stream (outside of SHE). Some 22% of flow originates in the upper sub-catchment of the Finchingfield Brook (also outside of SHE).

• The leaky debris dams installed in 2019 have been effective in reducing flood risk to Finchingfield since they have restored the floodplain function of the brook, causing it to overflow during extreme events, flooding the surrounding riparian grassland, instead of the village just downstream.

• The 2019 Beaver reintroduction has created a new wet woodland with at least 1.66 ha of wetland storing 1.66 m3  of water for each 1cm of water depth.  During an extreme event in the winter such as Storm Henk (2024) this wetland is capable of storing 7.5% of the water generated by the area upstream.  The much larger beaver enclosure on the Finchingfield Brook has, within two years, created significant areas of wetland on this much more significant stream.  Though beaver dams do breach, as a result of water overflow or treefall, they are rapidly repaired ensuring their role in natural flood management is maintained long-term.

• Soil moisture dynamics in the agroforestry plots show very high spatial variability within  and between fields.  They dry out significantly in the summer, particularly near the surface and from July to September.