William H. Schlesinger
Cary Institute of Ecosystem Studies
Schlesinger has spent his career examining human impacts on the natural cycles of elements like carbon and nitrogen at the Earth’s surface. These studies are far from esoteric: They provide estimates of the carbon content of vegetation and soils. They show how humans have reduced the storage of carbon in forests and soils. They reveal the potential to reverse that trend, so that forests can take up some of the carbon dioxide that is emitted to the atmosphere by burning fossil fuels. For a number of years, Schlesinger managed the Free-Air Carbon Dioxide Enrichment (FACE) experiment in central North Carolina. Experimental plots in a pine forest were treated with levels of carbon dioxide that we expect to see in the future. As a result, forest growth in these plots increased by about 15%, but only small changes occurred in the forest soils. Thus, some additional carbon sequestration will occur in temperate forests, even without any changes in forest management practices. But even greater success in carbon sequestration will be seen by preventing tropical deforestation and by reforestation of suitable areas.