Monitoring the health of Queensland's rivers: steps to designing an optimal spatial sampling scheme

  • Date: 01/18/2008

Melissa Dobbie (Commonwealth Scientific and Industrial Research)


Simon Fraser University


Spatial sampling design is a key step in developing an optimal
large-scale, multi-objective aquatic monitoring program. Aquatic
systems can be complex and irregular, thus it is critical to ensure
that a spatial design is statistically valid, implementable, and
flexible for meeting objectives such as assessing ecosystem health.
Design of monitoring programs for assessing aquatic ecosystem health
has been an active area of research in the United States in recent
years, especially in relation to the US Environmental Monitoring and
Assessment Program (EMAP). In particular, there have been innovative
developments on the statistical front of spatial sampling design in
order to achieve more efficient, flexible and practical monitoring and
assessment. One such development is the generalised random-tessellation
stratified (GRTS) design (Stevens and Olsen, 2004 J. Amer. Stat. Assoc.
99, 262-278) which generates a spatially-balanced sample of natural
resource populations such as a stream network. This talk motivates
adoption of this approach, provides some detail of how it works, and
illustrates its implementation to the redesign of Queensland’s ambient
aquatic ecosystem health monitoring and assessment program.

Dr. Melissa Dobbie ( from Australia's
Commonwealth Scientific and Industrial Research Organization (CSIRO)
will be visiting Canada in January-February 2008 as the second AusCan
Scholar. Dr. Dobbie specializes in spatial-temporal modelling;
environmental modelling; the analysis of ecological, biological and
environmental data; the analysis of zero-inflated count data; and the
design of aquatic monitoring programs. She received her PhD from the
Australian National University (ANU) under the supervision of Professor
Alan Welsh.

The AusCan Scholar Program promotes interaction between the Australian
and Canadian statistical communities by providing funding for young
scholars from either country to spend an extended period in the other.
Details of the program can be found on the SSC web site:

Dr. Dobbie's talk at SFU is supported by the Pacific Institute for the Mathematical Sciences.

Other Information: 

PIMS Distinguished Lecture 2008