Huge carbon stores discovered beneath UK grasslands

 

A nationwide survey by ecologists has revealed that over 2 billion tons of carbon is stored deep under the UK’s grasslands, helping to curb climate change.

However, decades of intensive farming, involving heavy fertilizer use and excessive livestock grazing, have caused a serous decline in valuable soil carbon stocks in grasslands across the UK.

The nationwide survey was carried out by a team of scientists from the Universities of Manchester, Lancaster, Reading and Newcastle, as well as Rothamsted Research.

The team found that 60% of the UK’s total soil carbon stored in grasslands – covering a third of UK land surface – is between 30cm and 1m deep. The team estimated the total grassland soil carbon in Great Britain to be 2097 teragrams of carbon to a depth of 1m.

Though the effects of high intensity agriculture are strongest in the surface layer of soil, they also discovered that this deep carbon is sensitive to the way land has been farmed.

Dr Sue Ward, the lead author of the paper from Lancaster Environment Centre, said:

“What most surprised us was the depth at which we were still able to detect a change in soil carbon due to historic land management.

“We have long known that carbon is stored in surface soils and is sensitive to the way land is managed. But now we know that this too is true at considerable soil depths under our grasslands.

“This is of high relevance given the extent of land cover and the large stocks of carbon held in managed grasslands worldwide.”

In contrast, the soils that were richest in carbon were those that had been subjected to less intensive farming, receiving less fertilizer and with fewer grazing animals. The team found that soil carbon stocks were 10% higher at intermediate levels of management, compared to intensively managed grasslands.

Professor Richard Bardgett from The University of Manchester said:

“Our findings suggest that by managing our grasslands in a less intensive way, soil carbon storage could be important to our future global carbon targets, but will also bring benefits for biodiversity conservation.”

He added:

“These findings could impact how grasslands are managed for carbon storage and climate mitigation, as current understanding does not account for changes in soil carbon at these depths.

“Our findings suggest that by managing our grasslands in a less intensive way, soil carbon storage could be important to our future global carbon targets, but will also bring benefits for biodiversity conservation.”

The research is part of a five year research project, supported by DEFRA, aimed at managing UK grassland diversity for multiple ecosystem services, including carbon capture.

 


The paper, ‘Legacy effects of grassland management on soil 1 carbon to depth’ is available in the journal Global Change Biology.

Mould unlocks new route to biofuels

A cross-faculty team of scientists have made an important discovery that could aid the production of biofuels and produce important chemicals much more sustainably.

The team, based at the Manchester Institute of Biotechnology, is made up of scientists from the Faculty of Life Sciences and the Faculty of Engineering and Physical Sciences. They have identified the structure of two key enzymes that were isolated from yeast moulds. These enzymes play an important role in the production of hydrocarbons – long chains of organic compounds that make up plastics, lubricants and transport fuels.

homebackground62Using existing biofuel technologies, it would be impossible to replace the current industrial demand for fossil fuels with ‘greener’ hydrocarbons. However, this research, published in Nature, provides a more environmentally-friendly, scalable alternative for the creation of biological hydrocarbons.

Professor David Leys, who led the research, investigated the mechanism that causes the common yeast mould to produce kerosene-like odours, right down to the atomic level. The smell occurs when the yeast mould is grown on food containing the preservative, sorbic acid. The team found that yeast uses a previously unknown form of vitamin b2 to help them make the volatile hydrocarbons that cause the kerosene-like smell. This same process was also discovered to help with the creation of vitamin Q10.

Professor Leys clarifies:

“Now that we understand how yeast and other microbes can produce very modest amounts of fuel-like compounds through this modified vitamin B2-dependent process, we are in a much better position to try to improve the yield and nature of the compounds produced.”

David Leys and his team didn’t stop there and have published side-by-side papers in the same Nature edition. In their second paper, the team looked at how alpha-olefins are produced. Alpha-olefins are a high value, industrially crucial intermediary class of hydrocarbons. They are used in the manufacture of flexible packaging and pipes, synthetic lubricants in oils and can be added to detergents to improve their strength. Better knowledge of these olefins could prove key in allowing us to become fossil fuel independent in the coming years.

Professor Leys concludes:

“This fundamental research builds on the MIB’s expertise in enzyme systems and provides the basis for the development of new applications in biofuel and commodity chemical production. The insights from this research offer the possibility of circumventing current industrial processes which are reliant on scarce natural resources.”


Paper 1

White, M. D. et al. “UbiX is a flavin prenyltransferase required for bacterial ubiquinone biosynthesis” will be published in Nature on Wednesday 17 June 2015. Advance Online Publication (AOP) on http://www.nature.com/nature

Paper doi: http://dx.doi.org/10.1038/nature14559

This manuscript explains how the vitamin B2 is modified and thereby recruited in bacterial vitamin Q biosynthesis.

Paper 2

Payne, K.A.P. et al. “New cofactor supports alfa-beta-unsaturated acid decarboxylation via 1,3-dipolar cycloaddition” will be published in Nature on Wednesday 17 June 2015.  Advance Online Publication (AOP) on http://www.nature.com/nature

Paper doi: http://www.dx.doi.org/10/.1038/nature14560

This manuscript establishes how the modified B2 is used to support the fuel-like compound production.