Yale Environment 360: The large-scale planting of jatropha trees in the world’s arid regions could help reduce atmospheric levels of carbon dioxide, a new study says. Using computer models and data from plantations in Egypt, India, and Madagascar, a team of German scientists calculated that plantations of the durable, scrubby jatropha — which can also be used as a biofuel — could capture 17 to 25 tons of carbon dioxide per hectare annually. Jatropha is particularly suited for so-called “carbon farming” because it can…