Special Session - Marine and Coastal Applications in Landscape Ecology - Afternoon Session Chair(s): Nicholson, Matt¹, Hinchey, Elizabeth¹, Robbins, Brad², ¹ Atlantic Ecology Branch, Narragansett, RI² Landscape Ecology Program, Sarasota, FL
Friday, April 2, 2004 1:00 PM - 2:40 PM Apollo Room 8

Although applications in landscape ecology traditionally have been restricted to the study of terrestrial systems, the questions defining the science are equally relevant for marine systems. Indeed, knowledge of spatial pattern and the scales at which ecological processes take place is essential for effective management of marine environments. However, scattered and widely disparate field or ship-based observations historically precluded quantification of large-scale marine patterns. Recent advances in remote sensing and other technologies are permitting assessments of pattern and process that never before were possible. It is still unclear how the principles of landscape ecology can be translated into the marine environment, a three-dimensional milieu with physical and biological characteristics that often vary rapidly in space and time. This session will bring together researchers who are attempting to adapt the tools of landscape ecology to address ecological questions within marine and coastal systems. The unique challenges facing the growing field of “seascape” ecology will be addressed.

Linking spatial scale to process and pattern in marine estuaries. Garza, Corey^*,1, ¹ Center for Environmental Analysis, Los Angeles, CA, USA

ABSTRACT- Historically, many studies in landscape ecology have investigated how the physical features of a habitat (e.g. spatial scale) can affect the complex ecological interactions often observed in many ecosystems. Many of these studies have been conducted in terrestrial communities while few studies have examined how the physical features of marine communities can affect the interactions that occur between biological and physical processes in these systems. In this talk I will describe survey data collected as part of the USEPA Environmental Monitoring and Assessment Program (EMAP) that was used to discern a relationship between spatial scale and ecological processes in marine estuaries. In this survey, sites were randomly selected at three spatial scales using a probabilistic site selection algorithm applied to a GIS map of all U.S. coastal estuaries. At each site and sampling scale, data relating to invertebrate species diversity and sediment and water chemistry were collected. Additionally, measurements were made of anthropogenic inputs into each estuary. My analyses revealed that many estuary species, in particular polychaetes, displayed an increase in diversity towards the equator. It would also appear that across latitude both the rate of increase in and total diversity were affected by variation in the spatial scale over which the survey was conducted. Furthermore, variation in scale also affected interpretations of the magnitude to which natural and anthropogenic inputs affected species diversity. In particular, the data suggested that increases in scale obscured the negative relationship between anthropogenic inputs and species diversity across latitude in coastal estuaries. The results of this study suggest that assessments on the strength of the relationship between biological and physical processes and species diversity in coastal estuaries can be strongly affected by variation in scale.

KEY WORDS: marine estuaries, spatial scale, species diversity