According to the Washington-based Earth Day Network's recently released Urban Environment Report, Detroit needs more parks to help lower pollution levels and improve residents' quality of life. The city ranked last in a study of 72 cities based on 200 environmental, health and quality-of-life indicators, including toxics and waste, air quality, drinking and surface water, human and public health, and global warming/climate change. The purpose of the study is to encourage participation in environmental conservation activities. Fargo, N.D., topped the Earth Day list, scoring highest for maintaining its air quality.