Problem Area 1
Improved methods are needed for efficiently detecting forest threats, identifying meaningful change, and interpreting landscape patterns and processes.
The ability to observe and track threats from pests, climate, extreme weather, wildland fire, and land-use or land-cover change is fundamental to effective forest management. Forest monitoring depends on the availability of data, but data alone are not sufficient. A variety of regularly collected data streams, including Forest Inventory and Analysis (FIA) data, weather station observations, and satellite imagery are gathered at multiple spatial and temporal scales. Other ancillary data sources such as demographic or socioeconomic data are routinely gathered by various agencies and institutions. These sources provide a wealth of potentially useful data. The greater challenge is integrating these complex data streams to derive meaningful metrics for detecting potential threats, assessing forest conditions, and tracking change. Innovative foundational research is often necessary to overcome this challenge. New monitoring methods, metrics, and strategies must be evaluated for their sensitivity and effectiveness for their intended purposes.
The primary monitoring efforts of the Center are twofold: 1) to provide up-to-date information regarding specific threats to areas and resources of concern, and 2) developing specialized tools and techniques to improve monitoring. The Center provides critical details about the current location, scope, and status of recognized threats, and these efforts often serve as a basis for important and recurring Forest Service reporting efforts. In other cases, the Center highlights previously unrecognized threats, thereby serving as an early warning system. Vegetation monitoring conducted by the Center typically spans large geographic extents and multiple years; at these scales, such monitoring provides the context needed to separate changes of concern from normal forest dynamics. The broad scale of this work puts the Center in a unique position to provide synoptic evaluations that are impractical at finer scales.
The Center’s wide purview often demands novel approaches and tools for inventory and monitoring, including the synthesis of initially disparate data streams. For example, the Center actively seeks new methods to combine and leverage remotely sensed data (including airborne and satellite surveys) with ground-based measurements in order to understand forest changes within a greater regional or national management context. Remote sensing observations provide regional perspectives that cross vegetation types and jurisdictions, but these data typically are of moderately coarse resolution. For instance, the five-year National Land Cover Dataset products distinguish forests from grasslands at 30-meter resolution, but they do not distinguish compositional changes within forests or grasslands. In contrast, field-based data such as FIA monitoring plots provide more power to examine local phenomena, but represent a comparatively sparse landscape sample and are collected less frequently than remotely sensed data. The respective strengths and weaknesses of these alternative data sources are largely complementary, so that their effective combination promises a more rigorous and holistic view.
The Center’s monitoring efforts may target the condition of forests directly or the stressors that can affect landscape change. Importantly, the occurrence of even moderate levels of tree damage and mortality do not necessarily indicate problematic or abnormal conditions, as forest species and ecosystems are commonly adapted to and may even depend on specific stressors for their persistence. For instance, many ecosystems are adapted to short-term climatic stress such as temperature or moisture extremes. Recognizing the distinction between normal and abnormal conditions calls for nuanced inventory and monitoring approaches that are attuned to historical baseline conditions. One example of the need for nuanced monitoring is wildland fire in fire-adapted ecosystems. In order to understand the status of fire-adapted forests, researchers need to track the absence of wildfire as much as the direct effects of fire. In contrast, nuanced monitoring of native insects or diseases is considerably more difficult. Biotic agents are often numerous, populations can erupt naturally and unpredictably, historical data are limited, and effects are more difficult to ascertain. The Center aims to comprehensively understand native stressors so that they can be more intelligently monitored as indicators of significant change.
In addition to monitoring direct indicators of forest change and native stressors, the Center also tries to anticipate the effects of non-native invasive species. By understanding invasive species’ distributions and spread, Center scientists and partners can monitor the factors that govern their movement and predict how and where invaders might spread, as well as estimate their likely impacts before they arrive. This includes efforts like monitoring the movement of firewood and nursery products that convey alien species of concern quickly over large distances. By characterizing primary pathways for the movement of non-native invasive species, and developing approaches to monitor these pathways, it becomes easier to focus on the critical task of determining which species are likely to be major threats (or threatened), or evaluating the potential extent of their impacts.
Monitoring can be exploratory, designed to determine status or to summarize conditions, or it can be confirmatory, designed to verify or test results of prior management actions. In either case, monitoring is more likely to be utilized and maintained long-term if it is efficient and cost-effective. Mechanisms should be in place to evaluate and, if necessary, modify detection and monitoring efforts based on feedback from resource managers, policy-makers, and stakeholders.
Problem 1a. Detecting forest threats, monitoring their extent and severity, and tracking forest conditions through time require new methods and tools for processing, measuring, and interpreting observational data, as well as new techniques to combine multiple data sources in novel ways.
Problem 1b. Scientists and managers tasked with characterizing forest ecosystems require timely summaries of the status of current and emerging situations within and surrounding those ecosystems. A lengthy record of monitoring over a wide geographic area and across all types of land use/land cover is needed to help provide important context for interpretation and management insights.