The tighter purse strings which have cut the returns from UK farmers' core agriculture operations are capping profits from a lucrative sideline too – rental income from mobile phone masts.

The rental revenues that landowners received from mobile phone operators for accommodating masts jumped 8.4% to £7,335 apiece last year, research from property consultancy Savills said.

However, a spate of operational tie-ups and mergers between mobile operators, aimed at promoting cost cuts, has put the brakes on this gravy train.

"The recent trend of service providers amalgamating and consolidating aerials is likely to see pressure on this income source in the next 12 months," Savills said.

Operators Vodafone and O2 in March unveiled a pan-European network-sharing agreement, while Oragne and T-Mobile last month unveiled a full UK merger.  T-Mobile and 3 two years ago announced a mast-sharing deal.

The UK has about 52,000 masts, including equipment sited on urban buildings as well as standalone rural poles.

'Star performer'

Savills made the prediction in a report showing that net income to English country estates rose by 6% to £102 per acre in the 12 months to April.

"Agriculture was the star performer," the report said, contributing 36% of gross income, putting it in line with housing assets.

For estate owners to run their own farms proved more lucrative than renting them for the first time in a decade, returning £110 per acre, although this advantage looked "unlikely to be maintained" as lower crop prices hit home.

Much of these profits were ploughed back into farm repairs, spending on which jumped 65% to £7.65 per acre. Estates with dairy farms, which enjoyed soaring prices until midway through the year, spent £24 per acre.