Urban environment density

Caprio, R J, Margulis, H.L., Joseloe, M.M. Lead absorpton in children and its relationship to urban traffic densities, Arch, Environ. Heath, 28, 195, 1974. 

SIR models typically are used to model a single population of the host species. However, metapopulation dynamics can be incorporated by linking individual colonies (each with its own SIR model) via prairie dog and flea movement parameters, /ZpD and /Zp. These parameters can themselves be functions of the landscape context surrounding individual colonies. Flea movement rates, in particular, may be enhanced in urban environments because of the increased density of domestic predators. Once the SIR models are developed, numerical simulations can be used to conduct a series of experiments that evaluate the overall risk of human infection given particular combinations of parameter values. Furthermore, by basing parameter estimates on field data, empirically based models can be developed for specific urban areas being investigated. 

Safety in digging a slit trench work is a topic of high importance especially in an urban environment. Trenches in urban environment are characterized by the density of infrastructure found and the lack of space for normal street traffic and pedestrians during the works. Some of these works of digging a slit trench depend on workers perception and experience on site, due to absence of entries or downgrade of local buried infrastructure. 

Hatt BE, Fletcher TD, Walsh CJ, Taylor SL (2004) The influence of urban density and drainage infrastructure on the concentrations and loads of pollutants in small streams. Environ Manage 34 112-124... 

Contamination of urban soils by POPs such as PCBs is of concern for human and ecological health. Soil contamination by metals and persistent organics disrupts nutrient cycling and is associated with declines in density of sod microfauna and lower rates of decomposition of organic compounds (Carreiro et al., 1999 Pouyat et al., 1994), an important process for the removal of organic contaminants from the environment. Ironically, urban warming may counteract this effect in some locations (McDonnell et al., 1997). 

The dynamics of fire growth is strongly influenced by the kinematics of flow through porous vegetation and urban structures (the canopy). The local wind and turbulence environment at the source determines the initial spread of a fire. Wind profiles vary depending upon the density (porosity) of the surrounding objects, their distribution vertically or laterally, the presence of below canopy open regions, and the distance... 

Mead MI, Popoola OAM, Stewart GB, Landshoff P, Calleja M, Hayes M et al (2013) The use of electrochemical sensors for monitoring urban air quality in low-cost, high-density networks. Atmos Environ 70 186-203... 

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