By Manuela Andreoni SAO PAULO, May 9 (Reuters) – When Xing Yanling posted on WeChat about her visit to the Brazilian Amazon in April, she described to her friends in China the unforgettable sensation of being “enveloped by tens of thousands of shades of green.” Xing is no ordinary tourist. She leads the Tianjin Meat Industry Association, representing importers responsible for around 40% of China’s beef purchases from Brazil. Under her leadership…