Big questions in agriculture need bigger experiments
Multi-million pound North Wyke Farm Platform to compare agricultural methods at an epic scale.
18 September 2012
Imagine a study comparing the productivity of entire farms in a grassland ecosystem, recording the chemical constituents of water running from each field, detailing every input that goes onto the ground before finally measuring animal production. Now multiply that complexity by three contrasting farming systems and you're close to the scale and ambition of the North Wyke Farm Platform (NWFP).
Set in the Devon countryside at North Wyke, a part of the Rothamsted Research institute that receives strategic funding from BBSRC, the NWFP is one of the largest experiments underway in the UK and a unique project designed to compare different approaches to sheep and beef farming on forage yield, water and air and soil quality.
"The North Wyke Farm Platform is a facility that allows researchers to better understand aspects of the productivity and sustainability of grassland science and farming systems," says Head of Site at North Wyke Dr Phil Murray.
Officially launched in summer 2012, the farm platform is a BBSRC National Capability and funded via a national capability grant to provide a strategically important resource for the UK bioscience community. "The NWFP will help to enable researchers to tackle some of the biggest questions for food security, which is one of BBSRC's top strategic research priorities," says Dr Jef Grainger, Strategy and Policy Manager for the Agriculture, Food and Environment Unit at BBSRC.
Growing more food using fewer inputs, such as fossil fuel based fertilisers, is a major challenge in ensuring food security whilst reducing the negative impact that agriculture can have on the environment. The NWFP is now set to begin collating data which, Murray says, will ultimately provide a background and evidence for agricultural policymakers and policy development in the UK.
As you like it
The NWFP covers 67 hectares and specifically looks at the agri-environmental footprint of beef and sheep farming. The area has been sub-divided into three farmlets. The first serves as a control where conventional livestock practices will continue, such as using inorganic fertilisers to optimise grass growth for the yearling beef cattle, and sheep, to feed on. The second farmlet will largely replace fertilisers with nitrogen-fixing legume crops, such as red and white clover which can transfer plant growth-boosting nitrogen from the atmosphere to the soil via symbiotic bacteria living in their roots.
"We'll be able to compare optimal use of nitrogen fertilisers against biological fixation from legumes and see the impact that has on production," says Murray. "We want to optimise the production from our grasslands, but of course there's an environmental impact and the trade-offs are something we can look at."
The third farmlet will trial innovative species and varieties of plants, especially those being developed by the Institute of Biological, Environmental and Rural Sciences (IBERS), a sister BBSRC funded Institute. Examples include high-sugar grasses and deep-rooted plant varieties to lock carbon away in the soil and provide a controlled release of soil water in grasslands. This treatment will allow a greater degree of intervention and finer adjustment, allowing for precision farming techniques to be measured for example.
"The overall aim is to improve grassland productivity by optimising production from the three systems," says Murray. "Because we have the three contrasting systems, farmers will be able to see how they might use the outputs from the research to improve their own productivity."
The research aims to be as relevant and applicable to livestock farmers as possible, down to the last detail. For instance, at the farm platform, cattle and sheep will be housed separately during the winter, bedded on straw, and the farmyard manure produced will be returned to each respective farmlet.
Murray adds that they have established a group of farmers who will act as a 'sounding-board' for how they are managing the farmlets and who will ultimately champion the work to their peers.
Measure for measure
The big idea of the farm platform is to record inputs and outputs that go into, and come off each farmlet. But measuring what comes off each farm is a more complex issue than just weighing the animals reared to get a measure of productivity – many nutrients are washed away by rain for example.
This is where the design, layout and uniqueness of the site come into play. Most of the site is set against a natural slope with water-impermeable clay underneath, meaning that all the water falling onto and flowing off the site can be captured by simple structures called French drains. These stone-filled trenches contain a perforated pipe into which the water flows. The drains lead to 15 flumes where water-measuring instrumentation records the physical and chemical characteristics of the water that passes through.
"We can make many comparisons in terms of water quality, for example for nitrate, phosphorus, ammonium," says Murray. "And we're also measuring greenhouse-gas emissions from the system. The environment is a big issue within agriculture today, and on the farm platform we have full control over the inputs and outputs and we can measure."
At each of the 15 flumes, a data-reading station sends the water quality information and more than 200 instruments are deployed across the NWFP including those measuring rainfall, soil moisture and soil temperature. These are all reporting back to a central server every 15 minutes and the system can be monitored, controlled and adjusted from anywhere on the World Wide Web.
To obtain accurate data over the project's lifetime, it is critical to calibrate the multi-parameter water sensors. "One set of sensors is out in the field while the other set is back in the lab being calibrated," says Bruce Griffith of North Wyke's Sustainable Soils and Grassland Systems department. "We swap them every fortnight."
Griffith and colleagues have spent much of the past year testing and validating the site in readiness for the next phase when the new treatments begin. During the 2011-12 baseline period the team has been monitoring the site to understand more about the soils' nutrient content and structure. To this end, they've overlaid a grid over the farm platform with an intersection every 25 metres where they've taken a soil sample. This data is mapped using Geographical Information Systems (GIS) which are used as visualisations and to integrate information on local geography with statistics and analyses for all the NWFP data.
"Over 67 hectares that gives us more than 1000 soil samples," Griffith explains. "They are dried, ground and processed. They then go to the labs for analysis for total carbon, nitrogen, phosphorus and potassium measurement, as well as other factors such as bulk density analysis."
In fact, the team is trying to balance out some parameters such as pH, phosphorus and potassium levels over the whole site. "It's so the three farmlets we're comparing are in the same agronomic state in terms of productivity, fertility and going to grow similar yields at the start," he says. "Then we can change the management and compare the three systems and understand when they are similar, and if they are not, why not."
All's well that ends well
The NWFP is certainly an ambitious project built on an industrial scale so that the results can be applied to real farming systems that operate at similar scales. Construction of the infrastructure cost around £3.5M, which includes all 9.2 km of French drains, water quality measuring stations, and the instrumentation and laboratories. Murray adds that they have a National Capability grant which will run the project for the next five years.
"As a national capability, we're providing a background of core data against which other researchers can come and complete their own investigations," says Murray.
Other researchers include Defra scientists working on the Demonstration Test Catchment (DTC) project. Spread across three large river catchment areas in England, the DTC also aims to monitor environmental parameters in response to small-scale field manipulations.
The farm platform at North Wyke thus provides a unique farm-scale 'research hotel' for agri-environmental activities to attract researchers from different communities and disciplines to promote new ideas, better address key issues in sustainable agriculture, or to tackle old problems in innovative ways.
"This will ultimately be critical for informing land management decisions and policies that do not simply move particular issues for sustainability to another part of the farming system, and which take account of benefits and costs across the full range of services provided by agricultural landscapes," says BBSRC's Jef Grainger. "The NWFP presents a major opportunity for UK researchers to build on existing excellence and take a lead in this crucial area."
Follow the North Wyke Farm Platform on Twitter.
Tags: feature video