The North Wyke Farm Platform is an exciting new facility that is being built by BBSRC
and hosted here at North Wyke, part of Rothamsted Research, as a national capability for researchers
to come and better understand aspects of grassland farming and farming sustainability.
The Farm Platform consists of about 80 hectares of land.
Here we've split it into three different farmlets, each of about 20 hectares, all comprising
different waste to manage, beef and sheep farming.
The reason we can capture all the water in one place on the Farm Platform is down to
our soils and the slopes we have here.
We have clay soils starting about 30 centimetres deep so any water landing on the land will
percolate down through the soil, either run off the top, or hit that clay there and then
run sideways down the slopes.
And to intercept that, we put in French drains.
The drains are 80 centimetres deep.
They have a perforated pipe at the bottom of them and then they're back filled to the
top with stone.
All of the water coming off the 12.5 hectares of land behind us is being channeled down
to this H flume.
Because we know the geometry of the front of this H flume, and where the water is being
channeled through, we simply need to calculate the level inside that, the water level inside
that, to be able to turn that into a flow rate.
So coming through here at the moment on a drizzly day in the middle of the summer, we've
got approximately 1/2 to 3/4 of a litre per second, but during a heavy rainfall event
we can expect up to 100 litres per second coming through this flume.
In here we have a range of sensors that measure the water quality parameters, so the water
that is coming off the fields.
The first one we have here is a dissolved organic carbon sensor.
We'll take that off to have a look at.
So this is a UV absorption sensor.
The wavelength of light is passed through the water and it measures what is absorbed.
So that's measuring dissolved organic carbon.
And at present we can see that in the last 15 minutes the carbon's DOC content was 22.5
milligram per litre.
Another sensor we have, this is a multi-parameter sonde measuring a range of sensors, a range
of parameters.
This one is measuring pH, conductivity and temperature, turbidity, chloride, ammonium,
and dissolved oxygen.
The three systems that we're comparing on the Farm Platform are increase in the use
of nitrogen on the existing permanent grassland, to reduce the amount of nitrogen that we use
and increasingly use biologically fixed nitrogen from legumes, and thirdly in a rotational
system to include new varieties of grasses and legumes.
So all this data is pumped into the boxes, the computers, so we've got a present 2.9
milligramper litre of nitrate and nitrite N coming in off the fields.
The carbon sensors are reading 21.4 milligrams per litre of dissolved organic carbon.
This device is the bubble meter, so this is a device measuring flow inside the flumes.
So at present we've got 25.2 millimetres of water level inside the flume, which equates
to 0.6 litres per second.
So all that data is transferred to a radio telemetry unit inside this box and that's
beamed up to site using a UHF radio every 15 minutes.
We're comparing the different farms through a number of means.
We're looking at all aspects from production through to looking at the environmental impacts,
for example water quality, air quality, and grassland quality.
But on top of that we're also looking at the economic aspects of that in terms of how much
fertiliser we're using, how much diesel we're using, how many man hours and tractor hours
that are going into managing each of the three systems.
We're looking at a 3D landscape of the Farm Platform.
This is created from a 3D geographical information system using an aerial photograph, over layered
on radar, and also digitised information.
We can see, in red, the dots are the 25 metre sampling grid and the blue lines are the drainage
from the hydrologically isolated fields.
One of the big challenges in the food security area is about feeding more people globally.
At North Wyke here we're setup now to understand how we can do that on a grassland system.