Research Highlights - Inventory, Monitoring, and Assessment
Check out our 2013 Research Highlights, focusing on Science for a Healthy Environment and Better Quality of Life.
Ensuring the health and sustainabilityof the nation’s forests requires scientifically credible and timely information about the extent, location, health, and ownership of these forests and the possible effects of global climate change. Forest managers and policy makers need detailed data to assess sustainability, to make important business decisions, to evaluate wildlife habitat, and for many other things. The Northern Research Station’s Forest Inventory and Analysis (FIA) team is an important part of the national FIA network, which provides information on northeastern, midwestern, and Great Plains forests.
2013 Research Highlights
What Lies Beneath Bog Lake Fen
Evaluating changes to carbon levels with trace gas measurements
Peatlands accumulate carbon because of waterlogged, low-oxygen (anoxic) conditions that favor plant production over decomposition. With climate change, these carbon-rich systems could become lesser sinks for carbon or even potentially sources of carbon that would further exacerbate climate change. Anoxic conditions also allow for the formation of methane (CH4), a greenhouse gas that has 25 times (on a 100-year time horizon) the global warming potential of carbon dioxide (CO2). We directly measured gas exchange between peatland and atmosphere year-round using the eddy covariance technique, which is continuous, fast-response, large-scale, and noninvasive. Ongoing monitoring of CO2 exchange (beginning June 2006) and CH4 emissions (beginning April 2009) have captured dramatic changes in carbon balance. In summer 2011, record high temperatures plus a high water table caused extended warming (2+ meters deep) in the peat column, resulting in CH4 emissions 2.5 times greater than other study years. Summer 2011 also recorded the longest period of net uptake of CO2. Climate changes to spring/autumn seasons and precipitation patterns have also altered carbon production and decomposition. The annual carbon budget for Bog Lake Fen in Minnesota, where measurements overlap, showed CH4 contributed significantly (23 to 39%) and based on the global warming potential of each gas, CH4 easily offsets the CO2 sequestration.
Products & Resources:
Linking Land Use to Great Lakes water quality
Research helps prioritize investment of restoration dollars by predicting which watersheds will contribute to impaired water quality
Watersheds have an important influence on water quality and watershed characteristics can be used to predict stream water quality. Forest Service scientists used novel information---derived from the Landsat data archive describing forest canopy cover change, along with forest inventory data and existing land cover data---to predict total phosphorus and turbidity in Great Lakes streams draining into Lakes Superior and Michigan. In the Lake Superior basins, phosphorus output increased with the amount of land used for agriculture, recent forest disturbance, and persisting forest cover; turbidity measurements increased with recent forest disturbance, the amount of land in agriculture, persisting forest, and urban land. In the basins draining into Lake Michigan, phosphorus output was related to ecoregion, increased with urban land, and decreased with older forest disturbance and watershed storage; turbidity measurements increased in some ecoregions and with recent forest disturbance, and decreased as the amount of conifer forest increased. Forest Service scientists used these relationships to identify and prioritize restoration areas in watersheds without observed in-stream data. This prioritization of watersheds will aid effective management of the Great Lakes Watershed and result in efficient use of restoration funds, leading to improved near-shore water quality.
Products & Resources:
National Maps of Forest Carbon Stocks from FIA Data
Raster maps facilitate regional analysis and reporting
The United States has been providing national-scale estimates of forest carbon stocks and stock change to meet the reporting requirements of the United Nations Framework Convention on Climate Change. Although these currently are provided as national estimates by carbon pool and by year to meet greenhouse gas monitoring requirements, there is growing need to separate these estimates into finer scales so that strategic forest management and monitoring activities can be focused on various ecosystem services such as carbon storage enhancement. Through application of a nearest-neighbor imputation approach, spatially extant estimates of forest carbon density were developed for the conterminous U.S. by Forest Service scientists using FIA annual forest inventory data. Comparisons among imputed maps indicate strong regional differences across carbon pools. The carbon density of pools related to detritus input is often highest in forests suffering from recent mortality events such as those in the northern Rocky Mountains. In contrast, live-tree carbon density is often highest on the highest quality forest sites such as those found in the Pacific Northwest. Forest inventory plot maps provide an efficient and flexible approach to monitoring diverse carbon pools at national and regional scales while allowing timely incorporation of empirical data.
Products & Resources:
Effectiveness of Landowner Assistance Activities
Forest Service's Forest Stewardship Program Examined
The Family Forest Research Center, a joint venture between the U.S. Forest Service Northern Research Station and the University of Massachusetts, Amherst, in conjunction with the University of Minnesota, completed a study to evaluate the Forest Service's Forest Stewardship Program (FSP), the nation’s most prominent private forestry assistance program. The team examined FSP using a mixed-methods approach that included analysis of annual FSP accomplishments; a survey of state FSP coordinators; analysis of similarities and differences between assisted and unassisted family forest owners; and focus groups with family forest owners. They found that 1) FSP reaches a small fraction of eligible landowners; 2) states use FSP funds to address local private forest land issues; 3) landowners obtaining assistance commonly associated with FSP (e.g., management plans) differ from others in terms of some socio-demographics, ownership objectives, and land management actions, but not in terms of intent to sell or subdivide forest land; and 4) traditional FSP activities are not influencing inactive family forest owners to become active managers. Based on findings, researchers believe that current practices (e.g., state-level flexibility) help FSP reach its goals; alternative assistance-related efforts may increase the reach of FSP and support strategic goals; and data collection improvements may enrich future FSP evaluations.
- Michael A. Kilgore, Stephanie A. Snyder, Marla A. Markowski-Lindsay, Paul F. Catanzaro, David B. Kittredge, Kyle Andrejczyk, Brenton J. Dickinson, Derya Eryilmaz, Jaketon H. Hewes, Paula Randler, & Donna Tadle
Products & Resources:
2012 Research Highlights
First National Inventory Developed of Standing Dead Tree Biomass/Carbon
Scientists at the Northern Research Station have developed a nationally consistent and comprehensive inventory of standing dead trees for the National Greenhouse Gas Inventory and Biomass Assessments. The inventory replaces models that were generalizations of regional averages by broad forest types. Instead of missing the impact of disturbances such as droughts and insect outbreaks, their effects on standing dead tree biomass/carbon estimates can now be measured in yearly time-steps as opposed to decades. Additionally, beyond simply counting standing dead trees, emerging research on standing dead-tree wood density reduction and structural deductions improves the accuracy of carbon stock estimates of standing dead trees. Mapping these pools of biomass indicate they are very prevalent in forests of the western United States.
Mark Harmon, Oregon State University
New NRS Publication Released About Forests of the Northern United States
Northern Research Station scientists recently produced "Forests of the Northern United States," a detailed portrait of recent trends and current conditions for the 20 northern states bounded by Maine, Maryland, Missouri, and Minnesota. This assessment of the Nation's most densely forested and most densely populated quadrant presents conditions in terms of eight criteria related to sustainable forests. Details for individual northern states are included in more than 100 maps, graphs, and tables as well as in online data exploration tools. Overarching issues identified for northern forests include interactions of forests and people, managing invasive species, sustaining biodiversity, and sustaining capacity for forest management.
Sherri Wormstead, U.S. Forest Service Northeastern Area State and Private Forestry; Francisco Aguilar and Nianfu Song, University of Missouri
Shifley, Stephen R.; Aguilar, Francisco X.; Song, Nianfu; Stewart, Susan I.; Nowak, David J.; Gormanson, Dale D.; Moser, W. Keith; Wormstead, Sherri; Greenfield, Eric J. 2012. Forests of the Northern United States. Gen. Tech. Rep. NRS-90. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 202 p.
Downturn in the Forest Products Industry of the United States
In recent years, the forest products sector of the United States has been reeling in the wake of the housing collapse, domestic and international financial crises, and the global economic recession of 2007-2009. Hundreds of thousands of jobs have been lost in the forestry and related sectors of the economy, and wood product output has been reduced to levels not seen in decades. The pattern of the downturn has varied by industry. Globalization of manufacturing and expanded use of electronic media have contributed to a decline in U.S. pulp, paper, and paperboard output since the late 1990s. The collapse of housing construction since 2005 and movement of furniture production off shore have contributed to declines in U.S. wood product output. Northern Research Station scientists have analyzed the downturn, focusing on trends in forest sector economic activity and employment. The analysis points to structural changes that may be difficult to reverse, but also finds some prospects for growth in the future, including increased forest product exports and wood-based biorefining.
U.S. Forest Service: Ken Skog and Peter Ince, Forest Products Laboratory; Brad Smith, WO RD; Francisco Aguilar, University of Missouri; Don Hodges, University of Tennessee; Charles Keegan and Colin Sorenson, University of Montana
Estimating Tree Volume/Biomass for the National Greenhouse Gas Inventory
Nationally consistent and documented procedures for estimating forest volume/ biomass are central to both bioenergy assessments and National Greenhouse Gas Inventories. To fill this need, scientists from the Forest Inventory and Analysis program of the Northern Research Station have documented a national approach to tree volume/biomass estimation (Component Ratio Method), evaluated its output in comparison to past methods, and implemented it in the 2012 National Greenhouse Gas Inventory.
2011 Research Highlights
Hurricanes Disturb Non-tree Subtropical Wet Forest Species Composition
Hurricane disturbance caused pronounced and persistent changes in the non-tree species composition of a subtropical wet forest. A unique long-term Forest Service dataset tracked the response and recovery of tropical forest herb, shrub, and vine communities to multiple hurricanes over 21 years on the 13-ha Bisley Experimental Watersheds in the Luquillo Experimental Forest, Puerto Rico. Analysis by Forest Service scientists found that hurricanes had altered non-tree community species composition by promoting the dominance of rapidly spreading ferns and vines.
These findings contrast sharply with other evidence showing that hurricane effects on the tree community is often negligible over similar time frames. These findings are particularly significant because non-tree species comprise the bulk of forest vascular plant diversity.
Tamara Heartsill Scalley U.S. Forest Service, International Institute of Tropical Forestry
Royo, A.A.; Heartsill Scalley, T.; Moya, S.; Scatena, F.N. 2011. Non-arborescent vegetation trajectories following repeated hurricane disturbance: ephemeral versus enduring responses. Ecosphere 2(7):art77. doi:10.1890/ES11-00118.1.
How Large-scale Forest Conditions Influence Northern Goshawk Nesting
Efforts to better understand nesting habitat requirements of the northern goshawk, a forest-sensitive species in northern Wisconsin, were enhanced by a collaborative research-management project. Forest Service scientists analyzed 10 years of nest survey data from the Chequamegon Nicolet National Forest and found that the key determinant of goshawk nest occurrence was the ratio of conifer cover to aspen-birch cover surrounding a potential nest site.
The nesting habitat requirements of the northern goshawk, a forest-sensitive species in northern Wisconsin, were analyzed in a research--forest management collaboration. Goshawks are woodland raptors that use a variety of forest types for nesting, making it difficult to determine nesting habitat requirements at the regional level. The hawks are associated with mature forests with large trees and open understories but may select nesting locations as close as possible to foraging habitats. Forest Service scientists in partnership with the Chequamegon-Nicolet National Forest examined how landscape-scale forest composition and road density at several different distances from nest sites and random locations throughout the forest influenced goshawk nesting presence. Nest survey and monitoring data from 1997 to 2006 indicate greater conifer and less aspen-birch cover, and fewer primary roads are in the area surrounding nests. The key driver is the ratio of conifer cover to aspen-birch cover surrounding a potential nest site. These results are extremely useful in sustaining populations throughout the forest.
Forest Service partners: Dan Eklund and Matthew StPierre, National Forest System, Chequamegon-Nicolet National Forest, Wisconsin
External partner: Dean Anderson, Landcare Research, New Zealand
Tropical Wetlands Found To Be Among Largest Carbon Pools on Earth
In spite of the well known values and ecosystem services of tropical wetlands to biodiversity, fisheries, water quality and storm protection, few studies have examined the carbon stocks of these ecosystems or the carbon dynamics related to land cover change. Although it is abundantly clear that tropical wetlands, especially peat swamps and mangroves, are important in global C cycling, tremendous uncertainties exist about how they are changing, and their potential as a source and sink of greenhouse gasses. This information is greatly needed to better understand the global role of these ecosystems as well as for monitoring, reporting and verification in proposed programs for reducing deforestation or degradation as mitigation strategies to climate change.
Carbon pools of coastal wetlands are poorly described at present and their potential role in climate change mitigation strategies is especially important. Forest Service scientists working with international colleagues have found that, mangroves have among the largest carbon stocks of any tropical forest. They assessed above- and below-ground carbon pools in 25 mangrove sites across Micronesia, Indonesia, and Bangladesh, comprising about 40% of the global area covered by this ecosystem. As land cover change rates are the highest in mangroves of any tropical forest type, greenhouse gas emissions may be as high as 10% of that of the total from tropical deforestation.
Forest Service partners: Daniel C. Donato, Pacific Southwest Research Station; Matthew Warren, Northern Research Station; Melanie Stidham, International Programs
External partners: Daniel Murdiyarso and Sofyan Kurnianto, Center For International Forestry Research, Bogor, Indonesia; Markku Kanninen, University of Helsinki, Finland
Kauffman, J.B.; Heider, C.; Cole, T.; Dwire, K.A.; Donato, D.C. 2011. Ecosystem carbon stocks of micronesian mangrove forests. Wetlands 31:343–352.
Donato, D.C.; Kauffman, J.B.; Murdiyarso, D.; Kurnianto, S.; Stidham, M.; Kanninen, M. 2011. Carbon-rich tropical mangroves and climate change mitigation in a time of rising seas, Nature Geosciences Vol. 4 May 2011.
Forest Land Estimates Improved by Novel Automated Mapping Technique Using Winter Satellite Imagery
New satellite-based estimates are consistent with those from FIA plot-based data and suitable for filling the gaps between FIA plots
Most automated satellite-based approaches for mapping forest lands rely on summer satellite imagery and are usually inconsistent with FIA plot-based estimates. Incorporating winter imagery in the mapping approach helps reduce the abundant false positives for forest and forest disturbance that frequently occur during the growing season, especially where forest is intermixed with wetland and agricultural landscapes. Reliable estimates of forest lands between FIA field plots allow customers the opportunity to explore forest dynamics more confidently beyond the grid of FIA plots.
Forest Inventory and Analysis (FIA) plot data provide invaluable information about the distribution and health of our nation’s forests to scientists and the public alike. Forest Service scientists found that winter satellite imagery with the vegetation change tracker (VCT) could generate more reliable estimates of forest lands in the western Great Lakes area. These VCT data were consistent with those from FIA plots. The VCT is an automated forest mapping algorithm that exploits the Landsat archive to produce comprehensive maps of forest changes and is well-suited for filling in data gaps between FIA plots. Using winter imagery exploited sharp seasonal contrasts of forested and nonforested areas and enabled the removal of most false positives, providing an efficient and reliable option for filling in gaps between FIA plots. False positives for forest and forest disturbance are a serious problem for the gaps in many FIA data grids, especially in intermixed forest and wetland and agricultural landscapes.
Forest Service Partners: Ian W. Housman, Jeremy B. Webb, and Robert A. Chastain, Remote Sensing Applications Center; Sean P. Healey, Rocky Mountain Research Station; and Warren B. Cohen, Pacific Northwest Research Station
External Partners: Chengquan Huang, University of Maryland, Department of Geography
2010 Research Highlights
Shrubland birds and their habitats
Populations of shrubland birds all over North America have decreased to historical lows, causing great concern among managers, researchers, and the birding public. Birds are highly valued by Americans. According to a recent USFWS report, 20% of the US population is interested in bird watching, thus spending 85 billion dollars and creating over 800,000 jobs. Unfortunately, 13 percent of the world’s birds are threatened with extinction in the near future. Shrubland birds require constant management, and thus, the need for reliable knowledge to guide management efforts is acute.
UMass Amherst; White Mountain National Forest; MassWildlife; Connecticut DEP; NRCS; Northeast Utilities Foundation; Massachusetts Audubon Society
Wolf recovery and the future of Wisconsin’s forests: A trophic link?
Overabundant white-tailed deer populations have serious negative effects on understory plant community structure and composition. Wolves, which are top predators of deer, have been recolonizing central Wisconsin since the early 1990s. NRS scientist Keith Moser and partners from the University of Georgia are measuring trophic cascade effects, that is, whether wolves are reducing local browse intensity by white-tailed deer and thus mitigating the biotic impoverishment of understory plant communities.
Wisconsin DNR wolf territory data combined with Forest Inventory and Analysis (FIA) data were used to develop a landscape-level spatially explicit analysis protocol in FIA plots categorized as high wolf impact areas and low wolf impact areas. : Preliminary results suggest that seedling survival of preferred, browse- sensitive seedlings is higher in areas continuously occupied by wolf packs.
Ramana Callan and Nathan P. Nibbelink, University of Georgia, Warnell School of Forestry and Natural Resources, Athens, GA
Urban Tree Canopy Assessment Program
Despite millions of dollars spent each year by federal, state, and local governments on remote sensing datasets, decision makers sometimes still find that they lack basic information about their community’s tree canopy because these datasets have not been converted into practical, readily interpretable information. In the Urban Tree Canopy (UTC) Assessments Program, NRS scientist Morgan Grove, with a partner from the University of Vermont’s Spatial Analysis Laboratory, has developed advanced processing techniques that to help fill this information gap.
Jarlath O’Neil Dunne, University of Vermont
Housing growth in and near protected areas
America’s public lands include some of the most scenic and highly valued resources in the country and thus attract nearby housing growth. NRS researcher Susan Stewart and cooperators at the University of Wisconsin and Oregon State University analyzed housing data from 1940 to 2030, within and surrounding each national park, national forest and wilderness area.
They found that 28 million new housing units had been built within 50 km of protected areas and that 40,000 new houses were added within national forest boundaries. During the 1990s, housing growth averaged 13 percent nationally, but grew at 20 percent within 1 km of protected areas. If these long-term trends persist, another 17 million housing units will be built within 50 km of protected areas by 2030, greatly diminishing their conservation value. Concern about the integrity of protected areas has focused on developing nations, where resource use pressure taken off a protected area can intensify pressure on surrounding lands. In the U.S., our demands on resources are typically for scenic vistas and proximity to trails; this research alerts resource managers, state and local planning authorities, and conservationists that when houses are built to satisfy these amenity demands, forests are fragmented, habitat lost, migration corridors disrupted, and biodiversity reserves isolated.
Volker C. Radeloff, Anna M. Pidgeon, Urs Gimmi, and David P. Helmers, University of Wisconsin – Madison; Roger B. Hammer, Oregon State University; Todd J. Hawbaker, USGS; Curtis H. Flather, RMRS
2009 Research Highlights
Tree species distributions are responding to climate change
Changes in tree species distributions are a potential impact of climate change on forest ecosystems. Although NRS scientists have already examined this possibility with computer modeling, real-world examination of this possibility has been limited due to a lack of consistent annual forest inventories across the United States. However, the Forest Inventory and Analysis (FIA) Program of the U.S. Forest Service, has now provided such inventories, and NRS scientists are now actually testing climate change hypotheses.
- C.M. Oswalt, U.S. Forest Service, Southern Research Station
- A.O. Finley, Michigan State University, Department of Forestry
Updating information on forest resources
Northern Research Station (NRS) Forest Inventory and Analysis researchers, Patrick Miles, Charles Perry, Scott Pugh, and Ron Piva, in cooperation with FIA staff from the Southern, Northern, Rocky Mountain, Pacific Northwest Stations, and Washington Office, updated U.S. forest resource statistics from the 2002 Resources Planning Act (RPA) Assessment to provide information on the nation’s forests for 2007.
- W. Brad Smith, U.S. Forest Service, Washington Office
Data informs energy policy debates
Northern Research Station Forest Inventory and Analysis (FIA) scientists provided the Forest Service Washington Office’s Legislative Affairs staff with a series of data summaries and maps. This information helped the Legislative Affairs staff demonstrate to lawmakers the important contribution that National Forest System (NFS) and Bureau of Land Management (BLM) lands could make to the renewable energy portfolios of the United States.
- FIA units of the Southern, Rocky Mountain, Pacific Northwest, and Pacific Southwest Research Stations
- FIA Washington Office staff
Great Plains Initiative -- Preparing for emerald ash borer
The Forest Inventory and Analysis (FIA) National Inventory and Monitoring Applications Center (NIMAC), in partnership with cooperators from state forestry agencies in North Dakota, South Dakota, Nebraska, and Kansas, processed data from a nonforest tree inventory aimed at assessing the potential impact of the emerald ash borer (EAB) and other factors on the states’ tree resources.
- States of Nebraska, North Dakota, Kansas, and South Dakota
2008 Research Highlights
Database summarizes characteristics of private and corporate forest-owners
More than 50 percent of forested lands in the United States are owned by private citizens and corporations. A Northern Research Station publication and database makes it easier to understand who these owners are and how they use their land.
“Family Forest Owners of the United States, 2006” is the first comprehensive analysis of family- and corporate-owned forests in more than a decade. Data can be accessed on a state-by-state basis to better understand private forest characteristics, ownership objectives and future intentions, as well as issues and concerns.
Current analysis indicates that private forests are not being managed in a sustainable manner, despite many of the owners’ good intentions. With this detailed understanding, public land managers can develop programs and resources tailored to meet the needs of these significant land-holders, and thereby improve the overall health of all America’s forests.
- USFS Forest Inventory and Analysis in cooperation with USFS State and Private Forestry, federal and state agencies, universities, nongovernmental organizations, and, of course, the landowners.
Improved online databases enable customized reports for natural resource partners
Forest Inventory Data Online (FIDO) catalogs the vast holdings of forest data collected over decades, and puts it at the fingertips of natural resource partners and the public. The improved database, developed by Northern Research Station Forest Inventory and Analysis scientists, allows users to create custom reports on the forest resources of the United States. This web based interactive tool provides easy and quick access to the latest FIA data for a wide range of users, including public and private land managers, planners and researchers who need the latest forest resource information.
This database is also compatible with other forest inventory tools. For example, data from an ongoing inventory designed by The National Inventory & Monitoring Applications Center (NIMAC) and conducted by Wisconsin’s Department of Natural Resources was integrated with FIDO. The alteration of FIDO to fit Wisconsin’s data not only provided the state with the ability to conduct their own queries using FIA methodology, but it also accelerated the development of FIDO thus benefiting other FIA customers. In several midwest states, NIMAC and FIA staff designed an inventory of trees in non-forest areas, adapted data recorder software, trained the crews, and facilitated the data collection effort, which finished its first season this summer (2008). In Maryland, NIMAC staff developed a stand-based imagery classification methodology and transferred the methodology as well as input data to state Department of Natural Resources staff. Maryland is using the techniques to independently conduct analysis of natural resources in new areas, using skills and methods acquired from working with NIMAC.
2007 Research Highlights
State and regional carbon estimates now available for U.S. Forests
NRS researchers produced a tool that uses data from the Forest Service’s Forest Inventory and Analysis Program to produce state-level estimates of forest carbon stocks and net changes, beginning in the base year 1990.
- U.S. Environmental Protection Agency
Monitoring network helps Wisconsin Maintain its sustainable forest certification
To establish a monitoring network on Wisconsin’s state-owned forest lands, NRS Forest Inventory and Analysis scientists developed a fractal-based technique to create spatially balanced networks of sample plots. The technique assures an even distribution of plots across the forest and over time.
- Wisconsin Department of Natural Resources
Better monitoring for less cost on the Mark Twain National Forest
NRS scientists worked collaboratively with the Mark Twain National Forest to investigate ways to provide inventory and monitoring information. Each National Forest must develop a monitoring plan to track the implementation and effectiveness of its forest plan.
- Mark Twain National Forest