Hello Ecolog,

I'm aware of the use of nested quadrats to serve a couple of potential 
purposes when sampling a community. The approach records 
presence/absence of different species within differently sized quadrats 
(e.g., 1 m^2 nested within 10 m^2 nested within 100 m^2) at multiple 
locations within a site or study area. One application would be to 
generate species accumulation curves (e.g., estimate the number of 
species present at 1,000 m^2). Another application would be to ensure 
that a suitable quadrat size is available for estimating change in 
frequency over time or between sites. The rationale is that a common 
species should have frequency sampled on smaller quadrats (otherwise the 
data are all "present") and that rare species should be sampled on 
larger quadrats (otherwise the data are all "absent"). By using multiple 
quadrat sizes, it is more likely that most of the species will be 
sampled at an appropriate spatial scale.

My question is whether anyone is aware of an approach that uses the data 
for a given species from all of the quadrats to develop an index or 
estimate of abundance. Is there a theoretically sound way to use data 
collected at the different spatial scales? I'd appreciate any citations 
or approaches that list members could send my way.

Thanks!

Brian Mitchell
National Park Service
Southeast Region Inventory and Monitoring Division

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