How to balance eco-environmental improvement and investment shortage ----- practice from the eco-environmental public-private partnership projects in ChinaYu Fan, Yunhao Zhao, Lu Xin, Jing Lu, Shunqing Xu and Zhijie XuE3S Web Conf., 292 (2021) 03020DOI: https://doi.org/10.1051/e3sconf/202129203020