6CURRIE B A, BRAD B. Estimates of air pollution mitigation with green plants and green roofs using the UFORE model[ J]. Urban Ecosystems, 2008,11 ( 4 ) : 409-422.
7United States Department of Agriculture. Tools for assessing and managing community forests [ EB/OL]. [ 2012-12-30 ]. http : // forums, itreetools, org/.
