As China enters autumn, a dark, furry-clawed crustacean – no larger than a human palm – becomes one of the most sought-after delicacies in the country. Chinese hairy crabs, a national obsession traditionally raised in the freshwater lakes of the Yangtze River Delta, are now being farmed on a stretch of salt-affected alkaline wasteland in the northwest province of Shaanxi. The area along Yellow River floodplains is unsuitable for conventional crops, but farmers have transformed over 600 hectares...