About the Authors

Shuang Zhang

Contributed equally to this work with: Shuang Zhang, Yuxin Zhang

Yuxin Zhang

Contributed equally to this work with: Shuang Zhang, Yuxin Zhang

Keming Ma

mkm@rcees.ac.cn

Affiliation State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, People's Republic of China

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: SZ YXZ KMM. Performed the experiments: SZ YXZ. Analyzed the data: SZ YXZ KMM. Contributed reagents/materials/analysis tools: SZ. Wrote the paper: SZ YXZ.