ROME (Thomson Reuters Foundation) - Asian farmers are growing rice and rearing fish in the same fields to increase their income and reduce weeds, while Ghanaians are using crop residues as compost to boost yields.

Such eco-farming techniques could deliver nutritious, environmentally friendly food for a growing world, increase farmers’ earnings and make farms more resilient to climate change, according to campaigners.

“Agriculture is in transition,” Pasquale Steduto, regional program leader for the United Nations Food and Agriculture Organization (FAO) in the Middle East and North Africa told the Thomson Reuters Foundation.

“Climate change is adding new uncertainty as well as increasing uncertainty. By introducing agroecology principles, you can reduce the risks of exposure to climate change.”

Global food production is currently based on extensive use of costly chemical fertilisers and pesticides, which damage the environment and human health, experts said at a three-day agroecology conference, which began Tuesday.

Yet less than 30 countries globally, and only two in Africa - Ivory Coast and Mauritius - have laws and policies that support eco-farming, the FAO said.

“We have three big challenges to manage - climate change, food security, and the connection between agriculture, forestry, economy and employment,” said Stephane Le Foll, a French parliamentarian and former agriculture minister.

The solution, he said, is ecological agriculture, which replaces chemical fertilisers with natural methods, such as planting trees amid crops and rotating foods grown to improve soils and deter pests.

Le Foll is vice-president of the “4 per 1000” initiative, which seeks to increase carbon held in agricultural soils by 4 percent a year to combat global warming.

Soil naturally absorbs carbon from the atmosphere through a process known as sequestration which not only reduce harmful greenhouse gases but also creates more fertile soil.

Fertile soils produce more food, which would feed more people and farming that is profitable could resolve unemployment, Le Foll added.

Agroecology has proven to work in Africa, where farmers are already grappling with degraded soils and unpredictable weather, said Million Belay, co-founder of the advocacy group Alliance for Food Sovereignty in Africa (AFSA).

In northern Ethiopia, eco-farming techniques provided better yields than chemical fertilisers in five critical crops, including barley and maize, a project by the Institute for Sustainable Development, an Addis Ababa-based charity, found.

But donors’ focus on commercial agriculture in Africa is holding agroecology back, Belay said.

“Philanthrocapitalists like Bill Gates and others come in with a lot of money to promote commercial agriculture,” he told the Thomson Reuters Foundation, referring to wealthy businesspeople who invest in ventures with a social goal.

The Gates Foundation was not immediately available to comment.

Le Foll said more people could be brought on board by showing that agroecology is profitable. Costs go down while productivity remains the same or even improves, he said.