Research Issue
On an annual basis, insects severely defoliate more than 20 million acres of forested land in the conterminous United States, affecting a larger area and incurring higher economic costs than any other disturbance. However, the long-term costs and ecosystem consequences of insect outbreaks on forest health and productivity are difficult to quantify at the regional scale because of the variety of pests involved, differences in forest types affected, and varying spatial scale and intensity of the impacts. In particular, the effect of insect activity on carbon cycling and sequestration at the annual and decadal scale is poorly characterized.
Our Research
We propose the development of a multi-scale approach to monitor defoliation and its impacts on forest carbon cycling using MODIS, Landsat (or similar), and high-resolution imagery. Our overall objective is to quantify productivity and carbon sequestration effects of insect activity in two representative regions of North America (Mid-Atlantic Highlands and Upper Midwest/adjacent Canada) at the scale of MODIS products. Our analyses will provide estimates of defoliation extent and intensity, as measured through seasonal losses in leaf biomass and changes to forest productivity derived from Terra MODIS imagery. The research is premised on the identification of characteristic trends in forest phenology associated with defoliation that can be applied across years to map defoliated areas and resulting declines in forest productivity. Remotely sensed estimates of reduced forest production will then be used to drive LANDIS-II, a spatially explicit forest simulator capable of modeling insect impacts on forest biomass and successional dynamics.
Expected Outcomes
Our research will reduce the uncertainties present in assessing forest carbon sequestration under scenarios of insect perturbations and related feedbacks (e.g., harvesting and fire). This will facilitate more accurate carbon accounting at the regional and potentially broader scales. Through the use of simulation models, we will address potential future impacts under different forest management scenarios and differing assumptions about the spread and prevalence of damaging pests. Through the use of MODIS, we propose a monitoring and measurement system that can potentially be adapted for temperate and northern forests worldwide, and will provide a tool to facilitate both forest management and policy decisions.
Research Results
McNeil, BE, de Beurs KM, Eshleman KN, Foster JR, Townsend PA. 2007. Maintenance of ecosystem nitrogen limitation by ephemeral forest disturbance: An assessment using MODIS, Hyperion, and Landsat ETM+ Geophysical Research Letters 34: L19406.
Research Participants
Principal Investigators
- Philip A. Townsend, Department of Forest and Wildlife Ecology, University of Wisconsin - Madison
- Brian R. Sturtevant, US Forest Service- Northern Research Station Research Ecologist
- David J. Mladenoff, Department of Forest and Wildlife Ecology, University of Wisconsin - Madison
Research Partner
- Robert Scheller, Department of Environmental Sciences and Management, Portland State University
For further details log on website :
https://www.nrs.fs.fed.us/disturbance/forest_health/carbon_dynamics_insect_defoliation/
Research Issue
The Northern Goshawk is a forest raptor found at low densities throughout northern hardwood forests of the Great Lakes region, and is a species of management concern for the Chequamegon-Nicolet National Forest (CNNF), Wisconsin, and Hiawatha National Forests, Michigan. The species has a circumboreal distribution and appears to be quite flexible in its nesting requirements and prey base, which limits the applicability of literature on nesting and foraging requirements from outside of the Great Lakes region. Therefore, there is a need for local information on these aspects of Northern Goshawk biology to inform land managers of the most effective means to conserve the species. In addition, it remains unclear what effect timber harvesting, which influences forest composition, has on goshawks within national forests.
Goshawks are associated with mature forest with large trees and open understories, but they may select nesting locations as close as possible to foraging habitats. We examined how landscape-scale forest composition and road density at several different distance from nest sites and random locations throughout the CNNF influenced goshawk nesting presence. The CNNF applies a 30 acre no-cut buffer surrounding nests and a second buffer extending another 330 ft in which only uneven-aged timber management is permitted. Using 10 years of goshawk monitoring data, we are evaluating how forest type composition as a result of management practices within 3 zones of influence (e.g., 200, 500, and 1000 m) may help explain the occupancy of goshawk nests. Current efforts are using the same approach on goshawk nest survey data on the HNF to compare across landscapes.
The Climate, Fire and Carbon Cycle Sciences staff develops a sound scientific basis and appropriate tools for making local to international resource management, human health/safety, and policy decisions in response to climate change, fire, air pollution, and other threats to people, forests, and watersheds. By connecting climate change and fire research to societal values, we foster innovative management solutions to sustain forests and forest-based values, and improve our quality of life.
Research Issue
Research Issue![[Image] Map of Northern FIA Inventory Area.](https://www.nrs.fs.fed.us/fia/local-resources/images/fia/main/NRS-FIA.gif)