This photograph of the Yellow River at Zhongwei in Ningxia province was shot in January 2020, soon after China’s Ministry of Ecology and Environment launched new investigations here related, in part, to black, pitch-like pollutants resulting from untreated waste from an old papermaking mill. Even artists that work with seemingly natural materials such as paper and ink must be vigilant when it comes to how their work might unwittingly be negatively affecting the environment.