With European Union institutions locked in ongoing debates about making the Common Agricultural Policy (CAP) more sustainable, researchers say policymakers may be overlooking the importance ponds and wetlands play in making farms more environmentally friendly.

A new study by British researchers say farm ponds and small bodies of water can reduce carbon emissions and protect streams and lakes from fertiliser contamination. The pools of water that once provided water for livestock and irrigation have disappeared over the decades to put more land into production.

John Quinton of Lancaster University’s Environment Centre and a team of researchers have spent four years examining the environmental advantages of ponds. They found that the water bodies capture sediments that otherwise contribute to particulate air pollution, trap carbon, and absorb nitrogen and phosphorous produced by crop fertilisers.

The European Commission’s CAP proposals for beyond 2013 have called for expanding ecological areas in agriculture – including buffer strips, leaving land fallow and protecting natural water bodies.

In a setback for environmentalists, the Parliament and council of agricultural ministers have sought to weaken some of the “greening measures” outlined in October 2011 by Agriculture Commissioner Dacian Cioloş’s proposals released in October 2011 (see background).

Farm ministers meeting on Monday expressed doubts about proposals to reserve 30% of direct payments to farmers as an incentive to practice more sustainable farming. Meanwhile, a report presented the same day to the Parliament’s agricultural committee raised concerns that the Commission’s proposals were too complex.

Many agricultural ministers and farm lobby groups have complained that the Commission’s CAP proposals would create more work for farmers and potentially cut food production through measures aimed at reducing industrial-scale farming and creating uncultivated preserves.

Green groups fear a letdown

But conservation groups accused the Council and MEPs of seeking to weaken the “greening” measures.

The European Environmental Bureau, in a statement, accused the Parliament’s agricultural committee of “substandard work.” Véronique Rebholtz, coordinator of the Agricultural and Rural Convention group representing farm and ecology organisations, denounced the agricultural ministers, saying they “may miss the opportunity to create an effective and coherent greening component.”

The Lancaster University study – Mitigation Options for Phosphorus and Sediment, or MOPS – calls for protecting remaining farm ponds and encouraging their expansion.

“Ponds and wetlands have benefits not only for wildlife; they can also store floodwater and can potentially be used to clean runoff pollutants before they reach downstream rivers and lakes,” Quinton said.

“These results suggest that field wetlands can indeed be used to reduce diffuse pollution from agricultural land and we now need to work out how to make them even more effective and to look into the other benefits they can provide,” the Lancaster professor said in a statement.

Yet a century of agricultural intensification has led to the mass disappearance of small bodies of water on farms across the EU, according to a study by the European Environment Agency in Copenhagen. Meanwhile, the European Pond Conservation organisation notes that ponds are also vital to biodiversity yet are not protected under EU or national laws.