Modeling the impacts of hemlock woolly adelgid infestation and presalvage harvesting on carbon stocks in northern hemlock forests

To better understand the potential impact of HWA and presalvage activities on carbon (C) dynamics in northern hemlock stands, we used the Forest Vegetation Simulator and Forest Inventory Analysis data to model C storage and successional pathways under four scenarios: presalvage harvesting; HWA-induced mortality; presalvage harvesting plus HWA-induced mortality, and a no disturbance control. Our simulation showed that all treatments differed in total C storage in the short term, with HWA-induced mortality providing the highest total C storage due to regeneration and ingrowth of replacement species combined with retention of standing and downed dead wood. At the end of the 150-year simulation, all disturbance scenarios had significantly lower total C than the control. The cumulative net C gain, was lower for the two presalvage than HWA scenario, indicating that allowing HWA to progress naturally through a stand may result in the least impact to long-term C sequestration and net C storage. While differences were not significant on low hemlock density stands, impacts to the estimated 267,000 hectares of northeastern forests where hemlock is dominant could result in conversion to red maple and a net loss of over 4 million metric tons of potentially sequestered C over the next 150 years.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author