New Approaches in Embedded Networked Sensing for Terrestrial Ecological Observatories

Ecological observatories are a new class of multiuser research infrastructure designed and deployed to address a broad range of continental-scale ecological questions that until only recently were not technologically feasible. These highly networked ecological observatories, spread across the United States and featuring a diverse integration of programmable sensing capabilities and remote observational functions are expected to enable a transformation in the scope of environmental research, particularly in relation to understanding how global climate shifts and local and regional land use changes will quantitatively affect the composition, structure, and dynamics of the nation’s ecosystems and services. Observing systems research focused on terrestrial ecology is one of four core research application fields of the Center for Embedded Networked Sensing, which operates an engineering and experimental test bed located at the James San Jacinto Mountains Reserve, a biological field station that is part of the University of California Nat*Corresponding author: James San Jacinto Mountains Reserve, University of California, Post Office Box 1775, Idyllwild, CA 92549-1775. Phone: 951-659-3811; Fax: 951-659-0553; E-mail: [email protected] EMBEDDED NETWORKED SENSING FOR ECOLOGICAL OBSERVATORIES 193 ENVIRON ENG SCI, VOL. 24, NO. 2, 2007 INTRODUCTION TO ECOLOGICAL OBSERVATORIES UNDERSTANDING CHANGES IN THE COMPOSITION, structure, and dynamics of the nation’s ecosystems and services and how these changes are likely to affect us, present complex challenges that require the coordinated measurement of a wide range of physical and biotic elements (Hamilton, 2004; Porter et al., 2005). Fortunately, new generations of terrestrial and aquatic ecological observatories, building upon the successes of today’s active biological and marine field stations and incorporating the newest developments in remote sensing and information management systems, are allowing scientists to conduct environmental and ecological research over a broader range of temporal and spatial scales than previously possible (Arzberger, 2004). The new generation of ecological observatories (EO), featuring a diverse integration of programmable sensing capabilities and remote observational functions, will enable a transformation in the scope of environmental research, particularly in relation to understanding the interrelationships between local, regional, and continental-scale patterns and long-term processes. One of the most ambitious new EO programs at the National Science Foundation is the National Ecological Observatory Network (NEON !www.neoninc.org"). The mission of NEON is to provide the capacity to forecast future states of ecological systems for the advancement of science and the benefit of society by focusing on several key questions, or “grand challenges” (AIBS, 2003; National Science Foundation, 2000, 2003; National Research Council, 2001, 2003). Summarized these are: (1) how are ecological systems affected by changes in land use, climate, and biogeochemistry across a range of spatial and temporal scales? (2) how do changes in the availability and distribution of the nation’s water supply affect ecological systems? (3) how do the patterns and movement of genes and organisms across the continent affect biodiversity, ecosystem function, and the spread of infectious diseases and invasive species? In order to quantify and forecast these changes, NEON infrastructure must advance the integration of multi-scale, spatially dense, real-time, biologically relevant observations, many of which will be automated, by utilizing embedded networked sensors and other types of networked instrumentation (Senkowski, 2005). A core feature of ecological observatories is standardized networked instrument arrays deployed on towers, in soil, and underwater, situated at one or more of the primary climatic regions of the United States. NEON proposes to incorporate a cluster of three sites within a region, each centered in a land cover type that is urbanized, agricultural, and wild land ecosystems, respectively. Within each, there will be as many as 10 replicates of sensor networks and data acquisition systems in order to capture variability that would occur due to local site variation. The instrumented units are being engineered to provide continuous data streams that mechanistically relate to the core ecological questions and to be used for sampling key indicator organisms and processes that are most likely to be sensitive to ecological change. Instruments and data streams will be managed by a infrastructure specifically engineered to provide detailed and comprehensive “sensor-to-scientist” operation, including control and calibration of sensors and instruments, tools for data query and mining, statistical analysis tools, modeling and simulation capabilities, and scientific data visualization (Estrin et al., 2003; AIBS, 2003). Data uses will range from scientific, policymaking, and educational applications, and the systems as a whole will be sufficiently modular to add additional functionality and extend the overall number of observatories as new partner agencies and organizations become involved with NEON. During the past 4 years, the Center for Embedded Networked Sensing (CENS !http://cens.ucla.edu"), a National Science Foundation Science and Technology Center, has worked to research and develop new environmental and ecological observing systems technologies that have relevance to the technological and scientific needs of proposed ecological observatories such as NEON, CLEANER (the Collaborative Large-Scale Engineering Analysis Network for Environmental Research), and ocean observatories (CENS, 2005). An objective of the CENS terrestrial ecologists has been to address aspects of the carbon cycle through the followural Reserve System. This paper describes the various experimental and deployed embedded networked sensing systems at the James Reserve, and suggests how similar systems and related infrastructure will be key to meeting the engineering and science objectives of future ecological research.