Fertiliser focus: Holding onto the country’s derogation

Two million water samples over the past nine years, six catchments and 300 farmers; you might not have heard about the Teagasc Agricultural Catchments Programme (ACP), but it’s playing a huge role in allowing Ireland to hold onto its nitrates derogation.

Information is crucial in securing this derogation and that’s exactly what the ACP provides – lots and lots of information.

The programme measures nitrogen and phosphorus levels in six catchments across the country. Water is sampled from streams and soil samples are taken to examine and improve fertiliser use efficiency.

It is important to sample water at weather events like the heavy snow last week

AgriLand visited the Castledockerell catchment in Co. Wexford during the week and spoke with Tom O’Connell, the communications officer for the ACP. He stated: “The ACP is well positioned to play an important part in providing the evidence to support the drive towards environmental and economic sustainability on Irish farms.

“Increasing farm output while meeting nitrates and Water Framework Directive water quality targets pose substantial challenges for Irish farmers, but also presents an opportunity.

This opportunity lies in the potential to capitalise on Ireland’s sustainable farming credentials.

“The ACP has increased our level of knowledge and our understanding. It has helped secure Ireland’s derogation by building up our knowledge.

This project is generating more information. It is helping to complete a picture of what’s going on.

Working with 300 farmers

Crucial to the programme is its direct link with farmers. 300 farmers are involved in the programme across the six catchments.

Soil samples are taken on all of these farms. Advisors also work with these farmers to make fertiliser decisions and all fertiliser used on these farms is recorded and added to the data. Wells have also been set up on some farms to sample water at different depths.

AgriLand met Joe Doyle a few weeks ago. Joe has been participating in the programme since it began.

Joe stated: “It has definitely changed the way we farm; there’s no doubt about it. It has all been positive in this area. I think it made people respect the importance of soil sampling.

You can’t control the price of barley, but you can control how much fertiliser you use.

“We’re saving on our fertiliser. To make a profit we have to. We’re putting out less, but we’re putting out a better combination.”

Also Read: Tillage focus: Balancing cereal and milk production perfectly in Co. Wexford

Setting up catchments

The programme is centered on six catchments. A laboratory is set up at the bottom of each catchment, where water can be sampled.

Tom explained: “The concept of a catchment is like a basin. All of the rainfall is collected at the plug hole. So, all of the water collects at this kiosk [where the water samples are taken].”

An important step in setting up the programme was to set up the catchments in an area that is representative of farming in Ireland.

Tom explained: “We set up this programme with six catchments. These areas were chosen to be typical of farming in Ireland and to collect data from the water, soil, weather and socio-economic data from the landowners as well.

Aoife Stafford and David Ryan, research technicians with the Teagasc ACP

The sites weren’t picked on an intensive or unintensive basis. They were chosen to take representative samples of farming in Ireland.

“We have a catchment in Cork, which is representative of an intensive dairy region. The catchment we’re in here at the moment [Castledockerell, Co. Wexford] is a spring barley growing area. There’s a second catchment in Co. Wexford; it’s mainly grassland, but on heavier soils [Macamores].

Sampling water at the weir in the Castledockerell catchment

“We have two catchments in the north east. Dunleer has heavy soils and is a mixture of grassland and winter cropping. The catchment in Monaghan has drumlins and the catchment in the west has no surface rivers. It is a typical karst landscape in Mayo and is important for the western lakes such as Lough Corrib.

“There’s also a different profile in terms of phosphorus and nitrogen in each catchment. Nitrogen is well below WHO (World Health Organisation) standards. However, phosphorus is more complex and levels vary across sites and years,” he added.

Knowledge is key

A large amount of information is collected from each catchment every day at the on-site laboratory that works automatically.

“Every year, this machine takes 100,000 samples. That is the key to this project. We are measuring water non-stop; traditionally, you would have been taking samples and bringing them to the lab.

“In these weather events it’s really hard to get out and sample. That’s where this lab comes in.

National EPA (Environmental Protection Agency) water quality figures are based on samples taken a few times in the year. This research programme is sampling water constantly.

A weir was built at the kiosk to make sure that there was enough water available to sample when the water levels decrease during the summer.

The weir at Castledockerell

“In summer, we generally have low rainfall and nutrient concentrations go up.”

What is being sampled from the water?
  • Nitrogen – nitrate nitrogen;
  • Phosphate – total and reactive;
  • Speed of the water;
  • Height of the water;
  • Water conductivity – a proxy for the amount of ground water in the stream;
  • Water turbidity – the cloudiness of the water, a proxy for the amount of sediment in the water.

Recent weather is affecting results

Aoife Stafford is a research technician in the two catchments in Co. Wexford – Ballycanew and Castledockerell. She looks after the laboratory on the two sites, analyses samples and downloads the data from both kiosks. This week she has seen some results which are out of the ordinary.

“We’ve noticed that the levels are very unusual because of the snow melt. However, we don’t have a lot of extreme weather events and, as a result, we don’t have a lot of data to compare it too.

The phosphorus levels are high at the minute. The causes of this are both farming and non-farming. Each site is different.

“There was a lot of slurry spreading and ploughing in the few days before Storm Emma came and we’re seeing that in the results. It wasn’t immediate, but when the snow started to melt it washed the ground water and the surface water through. We’ve noticed a big increase this week.

“It’s nice to see the data from these extreme weather events because we have a lot of data for normal, everyday weather. When we have storms it’s good to see the effects in the stream.”

It has also been difficult trying to keep everything working correctly in the kiosk during the cold weather.

We have a heater in the kiosk; but it’s hard to manage it when the temperature is at -7° and even down to -10°. They’re very exposed areas.

Taking snap shots from hot spots

There are certain areas or soil types which will leach more nutrients than others. Gathering this information allows the reasons for this to be investigated.

There are areas which have been picked out in the catchments that are more likely to leach nutrients. These areas are being sampled once a month and during weather events, like the snowfall last week.

“By looking at the hydrology and soil type, certain areas have been picked where snapshot samples are taken to see are there hot spots where nutrients are getting to the water and why,” Tom explained.

Big picture

The ACP has collected data from many sources. Having this data allows a picture of what’s going on in the water and the soil to be painted.

“We know what’s in this stream. We have snapshots of the surface water and we know what’s happening in the soils. Every 2ha of land on the farms has been sampled at least three times now. We have two met stations in each catchment.

We’re recording what’s in the water, the weather and what’s in the soil. It’s showing that one size doesn’t fit all and every catchment is different.