Researchers studied logging roads in the U.S., finding that the roads and log landing areas had far denser soil than even logged parts of a forest.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/logging-roads-have-long-lasting-impacts-forests
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/mongabay
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/forests
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/deforestation
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/groundwater
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/united-states-america-us
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/ecology
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/environment
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/soil-erosion
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/forest-management