US$300 billion. That’s the money needed to stop the rise in greenhouse gases and buy up to 20 years of time to fix global warming, according to United Nations climate scientists. It’s the GDP of Chile, or the world’s military spending every 60 days.

The sum would fund simple, age-old practices to lock millions of tons of carbon back into an overlooked and over-exploited resource: the soil.

“We have lost the biological function of soils. We have got to reverse that,” said Barron J. Orr, lead scientist for the UN Convention to Combat Desertification. 

Rene Castro Salazar, an assistant director general at the UN Food and Agriculture Organization, said that of the 2 billion hectares of land around the world that has been degraded by misuse, overgrazing, deforestation and other largely human factors, 900 million hectares (almost 5 billion acres) could be restored.

Returning that land to pasture, food crops or trees would convert enough carbon into biomass to stabilize emissions of CO2, the biggest greenhouse gas, for 15-20 years, giving the world time to adopt carbon-neutral technologies.

The heart of the idea is to tackle the growing problem of desertification — the degradation of dry land to the point where it can support little life. At least a third of the world’s land has been degraded to some extent, directly affecting the lives of 2 billion people, said Eduardo Mansur, director of the land and water division at the FAO.

Marginal lands are being stressed around the globe by the twin phenomena of accelerated climate change and a rate of population growth that could lift the global tally to almost 10 billion people by 2050, he said. 

“The idea is to put more carbon into the soil,” said Orr. “That’s not going to be a simple thing because of the natural conditions. But keeping the carbon in the soil and getting that natural vegetation, grazing land etc. thriving again — that’s the key.”

Last month, at a UN conference on desertification in New Delhi, 196 countries plus the European Union agreed to a declaration that each country would adopt measures needed to restore unproductive land by 2030. In many cases, the revitalized areas could benefit the local community and host country through increased food supply, tourism and other commercial uses.

Key to returning dry lands to vegetation is the use of fertilizer, said Mansur. But decades of poor agricultural practices have resulted in misuse, either from using the wrong products, using too much fertilizer, or in some areas using too little so that the soil loses its nutrients.

“The problem unfortunately is big and it is growing,” said Mansur. “The main cause of emissions from agriculture is poor land management. But the solutions are known: sustainable land management, sustainable water management, sustainable soil management.”

Mansur stresses that the problem isn’t about reclaiming desert, but restoring wasteland that was productive before human intervention.

Nor is it merely a matter of planting trees, since each area has to be considered in terms of the people who live there and how they can live on the land sustainably.

Kenya, for example plans to plant 2 billion trees on 500,000 hectares to restore 10% of its forest cover, but it is also working on ways to adapt to the changes in climate.

“We have to improve our livestock and crops to be drought resistant or drought tolerant,” said Kennedy Ondimu, director of environmental planning and research at the country’s Environment Ministry. “We have to look at developing our indigenous vegetables and indigenous livestock gene bank apart from embracing hybrid crop varieties and livestock varieties. We need to prioritize animal breeding.”

Still, the tide of desertification won’t be easy to turn. Yet, Castro Salazar says dozens of countries are fighting back with programs designed to reverse the loss of farmland and at least 20 nations have major efforts underway to replant lost forests.

“All these countries were able to keep producing the food they needed and growing the forest cover,” he said. “The myth was that in order to increase your productivity and your food sovereignty and security you needed to slash or burn the forest. We documented that it’s not true.”

Source: Financial Post