Methodology and Statistics
International Conference, 24 - 27 September 2000
Hotel Bor and Castle Hrib, Preddvor, Slovenia


Watershed Frontier of Landscape Health Assessment in
Environmental and Ecological Statistics

G. P. Patil
Center for Statistical Ecology and Environmental Statistics
Department of Statistics
The Pennsylvania State University, University Park, PA 16802 USA

It is exciting to see that it looks now feasible to do landscape health assessment using remote imagery and multiscale landscape fragmentation. Using various technologies, it is now possible to provide snapshots of landscapes indicative of various features of interest pertaining to human societies, plant and animal communities, aquatic networks, etc. This information can be represented in various kinds of multicolor maps that depict political, natural, methodological, or other features. These multicolor maps provide a basis for comparative assessments of regions within a policy making and implementation context. It is also possible to extract meaningful profiles of management units, such as watersheds, that can be calibrated and compared in order to assess and manage watersheds of a region. These current developments are part of the environmental and ecological information superhighway and are at the cutting edge of regional policy research with remote imagery and geospatial information.

When a natural landscape is cast as a categorical raster map, a multiresolution characterization of spatial pattern can be obtained whereby the entropy is computed for a finer resolution map, conditioned on the values of a coarser resolution map. After application to a sequence of rescaled maps which have increasingly degraded resolution, the conditional entropy is plotted as a function of measurement scale (resolution), thus resulting in a multiresolution profile of fragmentation patterns.

For neutral landscapes that are simulated by multiresolution stochastic generating models, we present a method to directly compute conditional entropy profiles. Such profiles can provide benchmarks for comparing results obtained from raster maps of actual landscapes that are classified from satellite images. Results show that characteristic landscape types give rise to characteristic features of these fragmentation (conditional entropy) profiles.

Keywords: Multiscale landscape fragmentation profile, Multiscale assessment of landscapes and watersheds, Multiresolution stochastic generating matrices.

References

  1. Johnson, G. D., Myers, W. L., and Patil, G. P. (1999). Stochastic generating models for simulating hierarchically structured multi-cover landscapes. Landscape Ecology, 14, 413-421.

  2. Johnson, G. D., Myers, W. L., Patil, G. P., and Taillie, C. (1999). Multiresolution fragmentation profiles for assessing hierarchically structured landscape patterns. Ecological Modeling, 116, 293--301, 1999.

  3. Johnson, G. D., Myers, W. L., Patil, G. P., and Taillie, C. (2000). Characterizing watershed-delineated landscapes in Pennsylvania using conditional entropy profiles. Landscape Ecology. (Under revision).

  4. Johnson, G. D., Myers, W. L., Patil, G. P. and Taillie, C. (2000). Fragmentation profiles for real and simulated landscapes. Environmental and Ecological Statistics, 7(4). (To appear).

  5. Johnson, G. D., and Patil, G. P. (1998). Quantitative multiresolution characterizations of landscape patterns for assessing the status of ecosystem health in watershed management areas. Ecosystem Health, 4(3), 177187.

  6. Myers, W. L., Patil, G. P., and Taillie, C. (1999). Conceptualizing pattern analysis of spectral change relative to ecosystem health. Ecosystem Health, 5(4), 285293.

  7. Patil, G. P. (1998). Environmental and ecological regional policy research with remote imagery and geospatial information. Issues, approaches, and examples. Technical Report 98-1201, Center for Statistical Ecology and Environmental Statistics, Department of Statistics, Penn State University, University Park, PA.

  8. Patil, G. P., and Myers, W. L. (1999). Guest Editorial: Environmental and ecological health assessment of landscapes and watersheds with remote sensing data. Ecosystem Health, 5(4), 221224.

  9. Patil, G. P., and Taillie, C. (1999). Fitting a multiscale hierarchical generating model for thematic raster maps. Technical Report 99-0203, Center for Statistical Ecology and Environmental Statistics, Department of Statistics, Penn State University, University Park, PA.

  10. Patil, G. P., and Taillie, C. (1999). A Markov model for hierarchically scaled landscape patterns. In Bull. of the International Statistical Institute, Volume 58, Book 1. pp. 89-92.

  11. Rapport, D. J., Christensen, N., Karr, J. R., and Patil, G. P. (1999). The centrality of ecosystem health in achieving sustainability in the 21st century: Concepts and New Approaches to Environmental Management. Human Survivability in the 21st Century: Transactions of the Royal Society of Canada, University of Toronto Press, pp. 3--40, 1999.