What are the economic and environmental gains from lime application?

Agriland

a day ago

Why the application of Grolime is both an economic and environmental win.
Increasing soil pH of an acidic soil through the application of lime delivers a major reduction in nitrous oxide (N 2 O) emissions, improves grassland productivity and provides a cost-effective route to greater farm profitability.
In current farming practices, where reducing greenhouse gas (GHG) emissions is now a key objective for Irish farmers, the application of Grolime is an efficient and reliable route to enhanced sustainability.
In addition to being licenced by the Department of Agriculture, Food and the Marine (DAFM), all certified Grolime suppliers undergo twice yearly testing for total neutralising value, moisture value, and grading.
That is why sourcing agricultural lime through a certified Grolime supplier is so crucial.
Research from Teagasc shows that maintaining higher soil pH levels reduces N 2 O emissions by up to 39%.
Soil acidity is recognised as the 'master variable' given its ability to control nutrient availability and microbial activity in the soil, along with its direct impact on the levels of N 2 O emitted from the soil.
Research demonstrates that gaseous emissions increase when soil pH drops to between 6.0 and 6.2.
In addition, essential nutrients, including phosphorus (P), potassium (K) and magnesium (Mg) become less available to the plant when soil pH falls to such levels.
Correcting soil pH also generates an improvement in nitrogen use efficiency (NUE) from 35% to 53% where P and K is sub-optimal in the soil.
Building on the previously mentioned environmental benefits, liming acidic soils can release up to 70 kg N/ha/year from the soil's organic nitrogen reserves.
While this is also considered an environmental gain, it has the added advantage of reducing the need for chemical fertilisers, thereby lowering costs - equivalent to the value of a bag of urea per acre.
As Denis Griffin of Ardfert Quarry Products, a certified Grolime supplier put it: 'In monetary terms, a farmer would have to spend approximately €100/ha/year of chemical fertiliser to achieve that 70kg N/ha/year, whereas using 5t of lime/ha over five years costs €35/ha/year.
"This is based on the assumption that the soil is at optimal pH and subsequently maintained at this level.'
In the case of grass clover swards, research has proven that increasing soil pH from 5.5 up to 6.8 by liming generates up to 1.4 additional tonnes of dry matter (DM)/ha.
Therefore, spending money on lime to correct and maintain soil pH also makes economic sense, with Teagasc estimating a return of €6-€10 for every €1 invested in lime.
Balanced soil fertility and improved NUE go hand-in-hand as limed soils drain more efficiently.
This drainage helps to prevent soil compaction and creates better conditions for root growth and biological activity.
Lime also plays a key role in the soil's physical structure, fertility and biological activity.
Good soil structure is characterised by the presence of small, rounded aggregates or peds - clumps of particles bound by the action of soil constituents, including clay particles, organic matter and cations including calcium.
Stabilising these peds improves porosity, in turn improving water movement through the soil, reducing nutrient run-off and leaching.
However, lime must only be applied according to soil test results, as liming too much too soon can create new problems when it comes to nutrient lock-up and loss.
Soil analysis reports are valid for four years.
Grolime delivers the desired environment for optimum soil performance during each and every application and represents the best long-term investment that farmers can make when it comes to soil health.