The Rare Ecology of Hinksey Meadows
Grassland Ecologist, Dr Timothy King is a fellow of Wolfson College, University of Oxford and a fellow of the Royal Institute of Biology. He has studied the unique plant community of Hinksey Meadows for several decades.
Hinksey Meadow - a thousand years old
Why Hinksey Meadows matters
Since World War 2 Britain has lost 97% of it's meadows.
Only about 2000 hectares of semi-natural floodplain meadows (MG4) remain in Britain.
7 hectares of Hinksey Meadows is 1000 year old floodplain meadow grassland. It is classified as MG4a grassland, the most revered of flood meadow grassland of which 192 hectares only remain nationally. So it is the rarest of the rare.
In the opinion of the Floodplain Meadows Partnership, the country’s experts, the quality of the Hinksey Meadow is outstanding. “It is better than the Sites of Special Scientific Interest (SSSI) that make up Oxford Meadows Special Area of Conservation (Pixey and Yarnton Meads) and the New Marston SSSI fields on the River Cherwell.”
Lying between Bulstake Stream and Hinksey Stream, 2 hectares will be lost.
The Environment Agency say they will translocate the 2 hectares but this has never been carried out successfully. They have also promised to replace with a new meadow. But it won't have the same value.
The rest of the site is threatened by changes in hydrology. This would mean the loss of a unique landscape that is irreplaceable at a time of biodiversity collapse.
Grassland is second only to peat for storing carbon
Grasslands, including floodplain meadows are second only to peat for carbon storage.
Over the centuries, massive quantities of carbon have been trapped in deep soils.
Carbon trapping is fuelled by nutrient input from river water.
This Carbon from photosynthesis, silt, and roots extends to 2 m deep and is trapped in dead microbes, soil pores. The first results coming through from Open University research students on carbon capture in flood plain meadow soils suggest current carbon storage of up to 109 tonnes per hectare, comparable to that in soils of ancient forests and second only to peat.
In disturbing soil either to remove it or to plant a new tree in a flood plain soil, so much of this carbon may be released by bacterial or fungal action that it might take 20-30 years for the tree to replace it.
The Snakeshead Fritillary
A Unique community of plants
The Snake’s Head Fritillary is Oxfordshire’s County flower and is characteristic of traditionally managed flood meadows.Hinksey Meadow is one of the few sites in the UK are considered to hold wild populations.
An old country belief about snakeshead fritillary was that it followed the path of the Romans, springing up wherever their footsteps had fallen.
There were record numbers of the plant in 2021 - 376, (up from 289 in 2019) and vegetative plants 363 (up from 134 in 2019). Non-flowering adult plants (vegetative plants) are part of the fritillary life cycle and these develop for 3-8 years, increasing in leaf number.
Oxford Preservation Trust manages Hinksey Meadow in a traditional manner with hay cut in July, followed by aftermath grazing by cattle. This has created a thriving population of a whole community of plants that act as pollinators and a seedbank for the future. This botanical wonder is now threatened by the Oxford Flood Alleviation Scheme.
What's at stake
Flood plain meadow and the future
Increased urbanization in the UK over a century is threatening biodiversity found in meadows, according to The World Wide Fund for Nature (WWF).
One single wildflower meadow can host up to a hundred varieties of plants and numerous insects – including bees, butterflies, and beetles. Flood plain meadows are even more threatened.
The situation is reversible if we preserve wildlife corridors.
"Essentially you form corridors of 'good habitat' to allow animals, birds, mammals and insects to move between these islands and gradually their populations will recover," said the WWF.
Given the "treasure chest" status of Hinksey Meadows, do we really want to disrupt this wildlife corridor? Do we want to lose it to a channel, which is the most controversial aspect of the scheme?