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Disturbances from insect pests threaten ecologically and economically important goods and services supplied by forests, including wood production and carbon sequestration. We highlight the factors that influence these services’resistance, a term quantifying the initial response to disturbance. Insects inflict damage through a range of mechanisms, prompting distinct plant physiological responses that scale to influence ecosystem processes and, with time, goods and services. The degree and timing of tree mortality and defoliation affect the amount of residual vegetation available to support compensatory wood production and influence carbon sequestration by changing rates of detritus‐fueled decomposition. Compounding, or sequential, insect attacks may prime a forest for additional disturbance, further eroding wood production and carbon sequestration. Forest management practices that promote biological and structural diversity, and augment or retain limiting biological and nutrient resources, may buffer against the effects of insect pests on wood production and carbon sequestration.
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Insect and Disease Disturbances Correlate With Reduced Carbon Sequestration in Forests of the Contiguous United States
Major efforts are underway to harness the carbon sequestration capacity of forests to combat global climate change. However, tree damage and death associated with insect and disease disturbance can reduce this carbon sequestration capacity. We quantified average annual changes in live tree carbon accumulation associated with insect and disease disturbances utilizing the most recent (2001 – 2019) remeasurement data from National Forest Inventory plots in the contiguous United States. Forest plots recently impacted by insect disturbance sequestered on average 69% less carbon in live trees than plots with no recent disturbance, and plots recently impacted by disease disturbance sequestered on average 28% less carbon in live trees than plots with no recent disturbance. Nationally, we estimate that carbon sequestration by live trees, defined as the estimated average annual rate of above- and belowground carbon accumulation in live trees (diameter at breast height ≥ 2.54 cm) on forest land, has been reduced by 9.33 teragrams carbon per year (95% confidence interval: 7.11 to 11.58) in forests that have experienced recent insect disturbance and 3.49 teragrams carbon per year (95% confidence interval: 1.30 to 5.70) in forests that have experienced recent disease disturbance, for a total reduction of 12.83 teragrams carbon per year (95% confidence interval: 8.41 to 17.28). Strengthened international trade policies and phytosanitary standards as well as improved forest management have the potential to protect forests and their natural capacity to contribute to climate change mitigation.
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- Award ID(s):
- 1637685
- PAR ID:
- 10316155
- Date Published:
- Journal Name:
- Frontiers in Forests and Global Change
- Volume:
- 4
- ISSN:
- 2624-893X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3389/ffgc.2021.716582
