Urban development causes substantial disturbance to the soil ecosystem.  Removal of topsoil, compaction, and addition of transported materials modify physical, chemical and biological conditions of the soil.  This initial disturbance, coupled with subsequent anthropogenic inputs including fertilizers, pesticides, atmospheric deposits, urban contaminants, extreme heat, and foot traffic, have the potential to produce unique soil properties and soil foodweb in urban ecosystems.  Therefore, the main objective of this study was to investigate the impacts of the length of urbanization period on soil chemical properties and nematode community in vegetation patches receiving different intensity of anthropogenic inputs.  Based on historical maps, urban boundaries from 1920’s (old), 1960’s (medium) and 2000’s (new) were identified from three cities in northern Ohio; Canton, Massillon and Wooster.  From each urban age ring, one public school site constructed within the defined urban period was selected.  Linear transects were setup in the middle of the two large lawns several meters away from the road and from two roadside lawns.  Five soil cores were collected at equidistant along each transect. 

Results/Conclusions

Regardless of the distance from road, the longer the urbanization period the higher was the total soil C and N in Massillon and Wooster (P-values<0.01).  On the contrary, soils from newly developed sites in Canton contained higher total C and N.  It is likely that the difference in Canton resulted from different lawn management practices such as compost amendment.  Abundance and genus-level richness of nematodes were also greater in old sites than those in new areas in Massillon and Wooster (P-values<0.10).  Furthermore, the distribution of nematodes among 12 dominant genera significantly varied with urban age in all three cities (P-values<0.001).  Regardless of urban age, total C and N levels were also significantly higher in roadsides from old and medium-aged urban sites (P-values<0.01), whereas no detectable differences were found in new urban sites.  This indicates that overtime soil C and N build up more rapidly in roadside soils than in the lawns farther from the roads.  However, there were no significant differences in nematode abundance and richness in response to the distance from road.  This study suggests that the age of urban site has influence on abundance and richness of nematodes, and soil C and N contents.  Furthermore, major differences in soil C and N contents between different urban age rings may arise in tree-lots adjacent to the roads compared to lawns away from the roads.