MEDELLN: Land degradation will unleash a mass migration of at least 50 million people by 2050 as many as 700 million unless humans stop depleting the life-giving resource, more than 100 scientists warned Monday.

Already, land decay caused by unsustainable farming, mining, pollution, and city expansion is undermining the well-being of some 3.2 billion people 40 per cent of the global population, they said in the first comprehensive assessment of land health.

Land depletion threatens food security for all Earth`s citizens, and access to clean water and breathable air regulated by the soil and the plants that grow on it. The condition of land is `critical, alerted the Intergovernmental Science-Policy Platform on Biodiversity and EcosystemServices(IPBES).

`We`ve converted large amounts of our forests, we`ve converted large amounts of our grasslands, we`ve lost 87pc of our wetlands... we`ve really changed our land surface in the lastseveral hundred years, IPBES chairman Robert Watson said.

`Land degradation, loss of productivity of those soils and those vegetations will force people to move. It will be no longer viable to live on those lands,` he said.

The lowest number of 50 million migrants is a best case scenario.

It assumes `we`ve really tried hard to have sustainable agricultural practices, sustainable forestry, we`ve tried to minimize climate change,` Watsonexplained.

The high projection is based on a `business-asusual` approach in which rampant global warming wreaks havoc with the land fuelling desertification and drought.

By 2050, said the analysis, land degradation and climate change will reduce crop yields by 10cp globally up to half in some regions.

The report covers the entirety of Earth`s land, as well as the lakes and rivers it supports. It estimated that land degradation cost the equivalent of 10pc of global economic output in 2010.-AFP