my name is john d. liu. i've been documenting the changes on the plateau for 15 years. i first came here in 1995 to film an ambitious project where local people were constructing a new landscscape on a vast sca. transforming a barren land into a green and fertile one. the projecect certainly changed my life, convincing me to become a soil scientist. the lessons i've learned in the last few years have made me realize that t many of the human trageds that we regularly witness around the world, the floods, mudslides, droughts and famines, are e not inevitable. here on the loess plalateau i've witnessed that people can lift themselves out of poverty. ththey can radically improve their environment. and by doing so, reduce the threat of climate change. >> > [singing] >> when i first came to the loess plateau, i was astounded by the degree of poverty and degradation. and i w wondered, "how could the chinese people, the largrgest ethnic group oon the planet, and my fatather, and my o own ancestors come f from a place that was this barren?" china's loess plateau is a region that