Paludiculture (Wet farming) is an emerging way of producing crops and resources on peat soils in a truly sustainable way. The benefit of this system is that it allows the peat to stay wet enabling it to store carbon and reduce greenhouse gas emissions [1] something that a conventional farming system cannot achieve on wetland soils.
As we learn about this wet farming system and suitable crops, the data will increase and knowledge will evolve. The information provided here is current and accurate at the time of writing and presented in good faith.
Why grow Reed as a crop? Common reed has a range of uses with established markets and new opportunities opening up.
Economics Using reed for sustainable, low carbon materials in the construction industry appears to be of most interest and potential. For example to produce moisture-resistant MDF boards [2]
Climate control and peat restoration. The crop cover and raised water level stops the peat blowing away. Carbon emissions from the peat are reduced and the plants actively store carbon. Common reed has a large nutrient removal capacity and can reduce concentrations of phosphates and nitrates within applied irrigation water, passing cleaner water on downstream.
Biodiversity Reedbeds are important habitats to increase the range and value of wildlife on the farm and assist in improving the wider nature recovery network. Rotational harvesting may be the optimum way to create and maintain a high biodiversity level.
Crop Notes Reed is versatile, tolerating conditions from damp wet ground, to standing water over a metre deep. This can allow flexibility with planting time for a new reed bed as long as there is water available after planting for the plants to establish.
Reed growth is quick, growing up to 2m tall, with large, dense reedbeds formed. Use of existing wild reed plants to establish the crop is possible but dependent on site and time. The crop can be sown but planting of young plants is more likely to be reliable where conditions are less favourable. For quicker establishment, bought in mature plants can be used. Input costs will vary depending on option used.
Reed beds remain productive for years; regular winter harvesting increases the above ground biomass for harvest and strong regrowth.
Biomass production yields can vary. A cost effective balance between yield and nutrient input could be considered by using nutrient enriched water that has come from other farm areas drains/ditches, potentially yielding 25 t ha-1 yr-1. With the double benefit of capturing nutrient run off and cleaning the water before it moves downstream.
End Products
High Value Industrial Chemicals: Reeds have a strong potential for use as a biomass feedstock for conversion to high-value industrial chemicals. For example Reed silica in the manufacture of anodes in lithium ion batteries [3], improving soils and strengthening concrete.
Building materials and Thatch: Traditionally reed has been used as a roofing material and has established markets. But now, new products and uses as building materials are being developed. Reed as a composite material compressed into a fibre-board is light, fire-proof, breathable and resistant to rot when waterlogged
Bioenergy and Biogas production: Common reed can be used as an energy source, either for direct combustion (chopped or pressed pellets) or for conversion to a further fuel product.Harvesting time can be flexible depending on the end use. If harvested between December and April for direct combustion biomass the moisture content must be below 20% if holding in store and for good calorific value.Harvesting in October gives the better quality biomass for anaerobic digestion.
The UK imports 25% of its bioenergy feedstocks [4] due to current limited production here, this leaves a large market gap that could be filled by increasing UK production. Biomass power plant location data suggests infrastructure may exist near to areas where wet farming crops may possibly be grown.
Key Points
Common reed is a versatile, quick growing and resilient plant.
Harvesting equipment developed and available.
Harvest periods flexible depending on product and quality required.
Crop management is dependent on end use for the reed.
Reed provides good economic and environmental benefits.
As demand increases so must the supply of good quality reed.
Common Reed is becoming recognised as an agricultural crop [5].
Wetland crops need to become eligible for agricultural payments.
Resources:
Paludi–Prima project Putting paludiculture into practice https://www.moorwissen.de/en/paludikultur/projekte...
Conservation Biomass to Bioenergy End User Report RSPB Sally Mills, DECC https://ecosystemsknowledge.net/
Loglogic–Low ground pressure tracked vehicles and associated equipment https://www.loglogic.co.uk/
References:
1 W. Wichtmann, C. Schröder and H. Joosten (eds.) Paludiculture – productive use of wet peatlands: Climate protection – biodiversity – regional economic benefits. Schweitzerbart, Stuttgart. pp. 100- 101. (ISBN: 9783510652839)
2 Notabo Hlabano, Lloyd N. Ndlovu, Nqobizitha R. Sibanda, Lindani K. Ncube (2018) Production and Characterization of Reed and Wood Particles/Phenol Formaldehyde Resin Composite Board. International Journal of Composite Materials 8(2): 25-31. doi:10.5923/j.cmaterials.20180802.01
3 Liu, Jun & Kopold, Peter & A. van Aken, Peter & Maier, Joachim & Yu, Yanlin. (2015). Energy Storage Materials from Nature through Nanotechnology: A Sustainable Route from Reed Plants to a Silicon Anode for Li- Ion Batteries. Angewandte Chemie International Edition. 54. 10.1002/anie.201503150.
4 Digest of United Kingdom Energy Statistics https://assets.publishing.service.gov.uk/governmen...
5 Geurts, Jeroen & Fritz, Christian. (2018). Paludiculture pilots and experiments with focus on cattail and reed in the Netherlands. 10.13140/RG.2.2.12916.24966.