and there's another vital service that trees and plants prprovide: photosynthesis. vegetation reduces the greenhouse effect by taking cacarbon dioxide out of the atmosphere. a measure of what restoring nature can do has been shown here on china's loess plateau, where farmers have continued to prosper despite the worst drought in decades. >> [singing] >> since the beginning of the project, the soil that nurtures their crops has been accumulating organic material from plants and animals. this holds the moisture and contains carbon. what's interesting about this is all these root materials, all thihis other stuff, this is ororganic material. and this s organic material is m mixing together with thehe loess, ththe geologic soils here, andd is making a living soil. this is where the moisture resides. yesterday it rained and there's still moisture in the soil. this is where the nutrients are recycled so that each generation of life emerges here. and this is where the carbon is. whwhat's interesting aboutut th, they made e this field, this is s new, so they're helping to s

they make photosynthesis possible, they are critical to every plant that justin grows. so justin has totally revised the way his family farms along with many farmers like him across the great plains. they have retired their plows. they now farm in a way -- justin has not plowed in more than 15 years. he also has introduced enormous and ever-increasing diversity into his thousands of acres. so he keeps adding in new rotations of crops, and he also a ads in cover -- adds in cover crops. he plants mixes of crops, and those help protect and renourish the soil. he is the furthest thing from a small, organic local farmer, but his soils are rebounding in a really remarkable way. the levels of carbon and organic matter in his oils and the -- soils is and the level of life in his soils are beginning to approach the native prairie, and that's a really important achievement given how critical big farmers in the heartland are for all of our future. so i want to read just a little bit -- i spent many, many hours tromping around justin's fields with him. you walk on this beautiful ma