Forest Soil

Importance / Issues

Soils are a critical component of forest ecological health, since they provide vegetation with support, water and trace nutrients. We will focus on ratios of carbon to nitrogen (C:N) and calcium to aluminum (Ca:Al) in the soil. The impacts of atmospheric nitrogen deposition are measured through changes in C:N ratios in the soil. Ca:A; ratios are reliable indicators of the ecological impacts of acidic deposition.

Our overall goal is to monitor status and trends in the structure, function and condition of NETN forested ecosystems in order to inform management decisions affecting those systems. To do so, NETN will interpret and report the ecological integrity of NETN forested systems from monitoring data. The “ecological integrity” of an ecosystem is a measure of the structure, composition, and function of an ecosystem as compared to pristine or benchmark ecosystems operating within the bounds of natural or historic disturbance regimes (Karr and Dudley 1981, DeLeo and Levin 1997, Czech 2004). Ecological integrity can be assessed by comparing key elements or attributes of an ecosystem to a reference area or to historical measurements or modeling efforts. In this way, NETN hopes to provide reliable data to inform management decisions relevant to NETN forested systems, including NPS land management and forest harvest plans, exotic species control, deer population management, NPS internal development, and national pollution control legislation.

Protocol Development & Status

The Long-term Forest Monitoring Protocol was implemented in 2006 and 2007 at the following parks: Acadia NP, Marsh-Billings-Rockefeller NHP, Minute Man NHP, Morristown NHP, Roosevelt-Vanderbilt NHS, Saint-Gaudens NHS, Saratoga NHP, and Weir Farm NHS. Forest soil is part of the protocol and detailed in the SOP: Soil Measurements and Sampling. Forest plots will be monitored on a four year cycle. The protocol is expected to be finalized in 2008.

The NETN Forest Protocol is designed to monitor forest ecosystem integrity in a standardized and cost-efficient manner across NETN parks. This protocol must allow statistical inference of status and trends within and across parks with sufficient statistical power. The use of permanent plots will increase power to detect trends over time by eliminating spatial variation. The protocol will also facilitate comparison of NETN data with other NPS networks and regional data such as that from the USFS FIA program.

Potential Measures

The SOP for soil measurement and sampling will be used to characterize soil chemistry within the rooting zone and provide information on the effects of atmospheric deposition upon the ability of these soils to support forested ecosystems. Soil samples will be shipped to designated facilities for soil chemistry analysis. The SOP also includes a rapid assessment of earthworm presence, used to characterize the spatial extent of earthworms across the network.

Preliminary Monitoring Objective

Qualitatively assess forest floor condition and estimate trends in spatial extent of earthworms and trampling impacts.

Determine status and trends in soil Ca:Al and C:N ratios to assess the extent of base cation depletion, increased aluminum availability and/or nitrogen saturation impacting NETN forest soils.

Contact Information

NPS Lead: Kate Miller

Email: Kate Miller

207-288-8736

References

Czech B. 2004. A chronological frame of reference for ecological integrity and natural conditions. Natural Resources Journal 44 (4): 1113-1136.

De Leo, G. A. and S. Levin. 1997. The multifaceted aspects of ecosystem integrity. Conservation Ecology 1:3.

Karr J. R. and D. R. Dudley. 1981. Ecological perspective on water-quality goals. Environmental Management 5 (1): 55-68.