Study Objectives


Given the success of these previous studies and the need to expand coverage of these biomonitoring efforts, a new project was undertaken in 2002 to accomplish the following tasks:

  • establish additional permanent study sites in nine national parks in the NCR.
  • collect floristic and elemental data systematically within each permanent study site so that a baseline of lichen biomonitoring information is available.
  • assign species to indicator categories based on existing information about pollution sensitivity.
  • compare data from new sites with previously collected data wherever possible.
  • resample each site at five year intervals.

Management Questions

The management questions addressed by this study are:

  • What is the present distribution of species richness in lichen communities sampled in the largest parks of NCR?
  • How do community distribution, species richness and relative species abundance compare with what should be found in ecologically similar areas along the Potomac River?
  • What evidence is there for changes in air quality over time?
  • What evidence is there for present-day pollution hot spots? What are the implications when pollution thresholds are exceeded?