04 March 2015 | Online since 2003



Fertilisers destabilise grasslands in changing conditions


Fertilisation of grasslands significantly reduces their ability to cope with changing conditions even when they contain a diverse mix of plants, finds a global study involving Oxford University.

The research, published this week in Nature, showed that diverse grasslands were more stable over time but that this effect was weakened when the plots were artificially fertilised.

"More diverse areas are generally more stable because different plants will benefit from different things at different times," said Professor Andrew Hector of Oxford University's Department of Plant Sciences, senior author of the study.

"To take a simple example, if you have plants that thrive in heavy rain and plants that prefer lighter rain in the same field, then the total amount of plant matter in the field in a given year will be less dependent on rainfall as both types will balance each other out."

The study used an international network of natural grassland sites called the Nutrient Network (NutNet), maintained and monitored by plant scientists across the globe and led by Dr Eric Seabloom and Dr Elizabeth Borer of the University of Minnesota (UMN). At each site, plants were collected, sorted, dried and weighed to count the number of species and total mass of plants each year. These were compared over three years to give values for diversity and stability. Stability was defined as the average annual mass of plant matter divided by the variation in mass between years. The study further tested the effect of fertilizers on stability.

Fertilisers are known to drive down grassland diversity over time, but this study found that fertilised plots were less stable even before their diversity decreased. This effect was not expected based on previous results.

'"Finding the mechanisms by which the most diverse grasslands are less stable immediately after fertilisation took us completely by surprise,' said Dr Yann Hautier of UMN, lead author of the study.

"We certainly expected the grasslands to be less stable after fertilisation, but not in the way that it happened."

As fertilisation boosts total yields, it was expected to increase short-term stability by making small variations less significant. However, the study found that fertilisation disproportionately increased yearly variations in yield, particularly in the most diverse grasslands.

Dr Hautier will be joining Professor Hector at Oxford University this summer to further investigate this phenomenon at sites in the UK.

"We now know that fertilisation makes grasslands less resilient to change, even before we see decreases in diversity," said Dr Hector.

"This is something that we did not see in artificial grasslands in another project called BioDepth. This is similar to NutNet but uses controlled environments rather than natural outdoor spaces. Now we want to investigate how this effect develops in the longer term and would like to take a look at data from the Rothamsted Park Grass Experiment, the longest-running ecological experiment in the world.

"The experiment was set up by John Laws and Joseph Gilbert in 1856 to demonstrate the benefits of artificial fertilisers, and has been running ever since. Ironically, it has since told us a lot about the negative impacts of artificial fertilisers on biodiversity. We would like to compare this data to what we saw in NutNet to see how the effects pan out in the long term."

Download



Comments


No comments posted yet. Be the first to post a comment

To post comment without approval login or register

Display name

Please enter your name

Email (optional)
Comment

Please enter your comment

Post Comment

Your comment submitted successfully.Please wait for admin approval.

Some error on your process.Please try one more time.



Jobs


11 February 2015
Land Acquisition Manager UK
Searching of sites with potential for a PV Solar Farm. Acquiring land and rights to allow the installation of large scale PV ...

12 February 2015
Retail Manager
You will ensure that your team delivers fantastic customer service through their extensive knowledge and expertise whether it...

11 February 2015
SEASONAL STAFF
Children's Farm and Abbotsbury Swannery. Weekends and mid week shifts available....

11 February 2015
Digital & Print Designer
JJ is a 50 strong marketing communications agency, providing creative, digital, PR and media services to a blue chip client b...

27 February 2015
Animal Care Apprentice
Animal Care, Agriculture, Horticulture, Arboriculture, Veterinary Nursing, Trees and Timber, Sports Turf, entry requirements ...




Top stories you may have missed
2 February 2015 | Arable
Is EU membership damaging UK farming?

Is EU membership damaging UK farming?

Membership of the EU is damaging the British farming industry, according to...


29 January 2015 | Machinery and Equipment
Drones 'rapidly changing' agriculture

Drones 'rapidly changing' agriculture

BASIS has launched an accreditation for pilots of Unmanned Aerial Systems (...


23 January 2015 | Arable
UK wheat yields have potential to double

UK wheat yields have potential to double

UK wheat yields have theoretical potential to more than double over the nex...


23 January 2015 | Machinery and Equipment
Crowds flock to LAMMA 2015

Crowds flock to LAMMA 2015

Britain’s farmers flocked to Peterborough for the first day of LAMMA’15 to ...


22 January 2015 | Cattle
Don't blame supermarkets for milk crisis...

Don't blame supermarkets for milk crisis...

The crisis in the dairy industry is not the fault of supermarkets, accordin...


16 January 2015 | CLA
Families affected by HS2 face 'major wor...

Families affected by HS2 face 'major wor...

Transport Minister Baroness Kramer visited three rural businesses in Cheshi...


16 January 2015 | Machinery and Equipment
John Deere unveil new 6R tractor range

John Deere unveil new 6R tractor range

Spearheading the John Deere range of mid-size tractors from Mannheim, the n...


14 January 2015 | Animal Health
Monthly TB checks more effective than ba...

Monthly TB checks more effective than ba...

Regular testing for bovine TB could significantly reduce the number of infe...


12 January 2015 | News
Government regulations hampering UK agri...

Government regulations hampering UK agri...

Single-issue policy-making threatens to hamper, not help, the progress of U...


8 January 2015 | Cattle
2015: The year ahead for the beef market

2015: The year ahead for the beef market

2014 has been a “rocky old year” for the beef industry but better prices ar...