Earthworm ecology
Earthworms are vital for terrestrial ecosystems. Many aspects of earthworm ecology are still not fully understood. I'm currently carrying out research on their role in boosting plant growth, their movement through soil and their enhancement of soil quality. On the "wish list" is work on aestivation, earthworm casts and earthworm-bacteria interactions.
Extreme weather events are increasing due to climate change but how will this impact on earthworms?
Dr Tamsyn Kiss studied the impact that flooding has on earthworm populations.
PhD title: Extreme weather, flooding and food security – can earthworms save the planet?
Funder: White Rose Consortium (Universities of Leeds, Sheffield and York)
Dates: 2016-2019
The flip side to how earthworms are impacted by flooding is how the earthworms in turn effect soil hydrology.
Dr Jamal Hallam studied this question for his PhD.
PhD title:Earthworm – water relations
Funder: Islamic Development Bank
Dates: 2015-2019
Ley strips are known to help regenerate arable soil but what role do earthworms play in this?
As part of the NERC Soil Security Programme we were members of the SoilBioHedge project (2015-18) led by Prof Jonathon Leake at the University of Sheffield. Dr Miranda Prendergast-Miller worked as the earthworm postdoc. on the project, investigating rates of change in earthworm populations in the ley strips. Other investigators on the project (it was a cast of thousands job!) included Profs Mike Burrell, Rob Freckleton, Steve Banwart, Duncan Cameron and Drs Dylan Childs and Jill Edmondson (Sheffield), Dr Thorunn Helgason (York) and Profs Les Firbank, Joe Holden, Dr Richard Grayson (Leeds).
One of the mysteries about earthworms is that they almost always increase plant growth. No one knows why this is but we are trying to find out in a NERC funded project "Whispers in the dark - do earthworms talk to plants?" (NERC standard grant NE/M000648/1, 2015-16). The project involved Professor Jane Thomas-Oates who heads up York University's Centre of Excellence in Mass Spectrometry and Dr Kirsty High who did all the hard work as the postdoc. We tested the hypothesis that earthworms release plant growth promoting hormones which "naturally" boost plant growth.
In his best selling 1881 book on earthworms Darwin wrote "“Even on the same field worms are much more frequent in some places than in others, without any visible difference in the nature of the soil”. We investigated what controls the distribution of earthworms in pasture land in a collaborative NERC project involving Paul Eggleton and David Jones from the Natural History Museum, Ron Corstanje at Cranfield University and Jo Witton here in the department (NE/K015338/1, Scaling and thresholds in earthworm abundance and diversity in grassland agricultural systems, 2014). We hope to be able to determine whether modern agricultural intensification is likely to increase or decrease earthworm populations and all the ecosystem services that they are ultimately responsible for.
Dr Hongling Qin visited us for a year (2014) from the Key Laboratory of Agro-ecological Processes in Subtropical regions, Institute of Subtropical Agriculture, Chinese Academy of Sceinces, Hunan, China. Also involved in the project are Drs Sylvia Toet (York Environment Department) and Andreas Heinemeyer (Stockholm Environment Institute) and Prof Phil Ineson (York Biology). We are investigating the emissions of greenhouse gases - carbon dioxide, nitrous oxide and methane - due to earthworm activity to assess what role earthworms have to play in natural emissions of these gases.
Dr Luis das Neves Cunha is carrying out work on earthworms in the Azores to determine how they have adapted to living in soils that contain high levels of CO2 and elevated temperatures. This multi-disciplinary NERC funded project (NERC standard grant, NE/1026022/1, 2012-13) is led by Pete Kille at the University of Cardiff. Read about the project and our sampling trip at our Blog site. The earthworms we are studying have adopted some extremophile traits and our results may have applications in underpinning bioeconomy (biotechnology, agriculture and vericompositing), medicine (models for anoxia & hypercapnia) and environmental management (through ecotoxicology, regulation and reclamation).
Ms Alice Johnston is modelling earthworm field populations in response to pesticide applications.
PhD title: Modelling earthworm population dynamics in agricultural fields
Co-supervisors: Professor Richard Sibly (main supervisor), Reading, Dr Permille Thorbek, Syngenta, Dr Tania Alvarez, EcoRiskSolutions
Funder: BBSRC Syngenta Industrial CASE award
Dates: 2010-4
Dr Dan Carpenter investigated the role of earthworms form different ecological niches in the breakdown of primary silicate minerals and the development of soils.
PhD title: Influence of earthworms on the physical and chemical weathering of soil minerals.
Co-supervisors: Dr Paul Eggleton, Natural History Museum, Dr Caroline Kirk, University of Loughborough
Funder: NERC CASE award with Natural History Museum - NER/S/A/2004/12417
Dates: 2005-8
