Management Impacts on Forest Floor and Soil Organic Carbon in Northern Temperate Forests of the US

No overall trend was found between forest floor carbon stocks in stands subjected to partial or complete harvest treatments. A few sites had larger stocks in control plots, although estimates were often highly variable. Forest floor carbon pools did show a trend of increasing values from southern to northern sites. Surface soil (0-5 cm) organic carbon content and concentration were similar between treated and untreated plots. Overall soil carbon (0-20 cm) pool size was not significantly different from control values in sites treated with partial or complete harvests. No geographic trends were evident for any of the soil properties examined.Results indicate that it is unlikely that mineral soil carbon stocks are adversely affected by typical management practices as applied in northern hardwood forests in the US; however, the findings suggest that the forest floor carbon pool may be susceptible to loss.The development of international, state, and regional climate agreements that call for reporting and reducing the emission of greenhouse gases has led to increased interest in forest carbon inventories and a greater demand for information relating to forest carbon sequestration. In 2009, US forests are estimated to have offset 13% of national greenhouse gas emissions [1], which makes understanding the effects of forest management on forest carbon cycles a high priority. Soil carbon in particular is poorly understood; little is known about the rate of carbon accumulation, the maximum amount of carbon that can be stored in soils, effects of vegetation type, or the impact of forest management practices on soil carbon cycles. An international agreement designating the "maintenance of forest contribution to global carbon cycles" as Criterion Five in the Montreal Process for the Conservation and Sustainable Management of Temperate and Boreal Forests [2] has added to the need to understand the effects of commonly employed silvicultural techniques on key forest carbon pools.Cov