Farm leaders have called on the Scottish Government to provide extra financial support towards the cost of upgrading slurry storage.
NFU Scotland (NFUS) wants government to increase the Agri-Environment Climate Scheme (AECS) budget and to ring-fence funds within the scheme for slurry storage investment.
It also wants the Scottish Agricultural Capital Grants Scheme (SACGS), which provides funding for precision slurry spreading equipment and slurry store covers, to be extended.
The union says estimates suggest less than 2% of the £290 million of AECS funding allocated since 2016 has gone on slurry storage with only 134 slurry storage applications approved.
NFUS said the new slurry rules, which come into force over the next four years and require minimum slurry storage of 22 weeks for housed cattle and 26 weeks for housed pigs, will require significant investment on farms across Scotland.
It says the rules will be particularly challenging for farmers in economically fragile locations such as the Orkney beef sector and Kintyre milk field.
NFUS president, Martin Kennedy, said although government had earmarked £5m of funding for slurry storage this year, it “falls way short” of what is required by industry.
“The financial impacts of compliance with new regulations on slurry on some farms and crofts may threaten their economic viability,” said Mr Kennedy.
“A significantly enhanced support package is crucial to delivery of the new regulations and vital if production levels from some Scottish livestock farms and crofts is to be maintained.”
A Scottish Government spokesman said the new slurry storage rules had introduced improved controls to reduce the risks of pollution and ensure more targeted spreading of slurry to maximise the nutrient benefit and reduce emissions.
He said: “We understand that farms will not be able to introduce these changes overnight; the changes will be phased in, with some farms having up to five years to comply.”
The spokesman said the 2022 SACGS scheme would include funding for tools which are proven to lower ammonia emissions, such as low emission slurry spreading equipment and slurry store covers.
He added: “The AECS 2022 round is currently open for slurry storage applications for famers and crofters within the SEPA identified priority catchments, this includes parts of Orkney and the Kintyre peninsula.
“Farmers and crofters can check if the option is available on their holdings by checking the targeting tool on the AECS website.”