Sampling organisms while describing the continent: the development of NEON's observing strategy for organismal biology

Background/Question/Methods

 The National Ecological Observatory Network (NEON) will document ecological responses to drivers of change via three primary integrated data streams. At each NEON site, tower sensors will provide temporally continuous and spatially discrete data, aerial spectrometry and LiDAR will deliver temporally discrete and spatially extensive data, and field measurements will complement the sensor data by generating temporally discrete and spatially replicated measurements of biota, soil, and water. With respect to the field measurements, the observatory approach to organismal ecology presents challenges in the consistent and comparable collection of information at the continental scale and over decades. Here we discuss four general principles that guide the NEON field sampling: 1) site-specific measurements must contribute to a robust observation that is representative of the local site at annual and key phenological time steps; 2) sampling should be capable of detecting local process-level trends across spatial and temporal scales and multiple biological groups; 3) measurements should be co-located where appropriate and tied to ecologically significant estimates of the abiotic environment; and 4) observations should be suitable for integration with other data streams (e.g. sensor measurements) to facilitate the extrapolation of ecological patterns and understanding to regional and continental scales.

Results/Conclusions

Statistically robust study designs have been devised that integrate multiple types of biological measurements across both aquatic and terrestrial systems. The design framework is structured to capture site-specific, local-scale heterogeneity that will inform our understanding at larger spatial scales. Sampling of biota, soil, and water will be iteratively optimized as initial design assumptions are confronted with actual response data, and further adjusted to respond to patterns of change across landscapes through time. This presentation will highlight the manner in which sampling schemes are integrated to generate observatory data products that elucidate continental-scale ecology and enhance our ability to forecast change over time. Specifically, we present the general sampling design NEON will employ to capture long-term dynamics in soil biogeochemistry, soil microbial communities, infectious diseases, and plant, insect, bird, and mammal populations. We also present the current field sampling strategy to link plot-based measurements with data obtained from NEON’s tower and aerial remote-sensing instruments.