Geoscience Reference
In-Depth Information
Fig. 9.1
Location of study area and water quality sampling sites
the metropolitan area. Different parts of the study area are currently with differ-
ent levels of urbanization, which generally decreases from the City of Boston to
outside.
Over the past several decades, the study area has being experienced substan-
tial urban sprawl, characterized by population decline and stable land use change in
central city but rapid population growth and land development in suburban and rural
areas (Tu et al.
2007
). The rapid urban sprawl is continuing to cause the fast conver-
sion of undeveloped land, mainly forest, into developed lands, especially residential
land. Urban sprawl is continuing to put great pressure on the undeveloped land (i.e.
forest and agricultural lands) and the ecosystem in the study area, especially in the
interface of rural and urban areas (i.e. suburban areas). To evaluate the impact of
urban sprawl on water quality is very important for regional land use and watershed
management. In addition, the different levels of urbanization across the study area
might result in spatially varying local water pollution sources and watershed char-
acteristics, and thus relationships between urbanization and water quality indicators
might change across the urbanization gradient. As a result, it is quite appropriate
