title: Using GIS to generate spatially balanced random survey designs for natural resource applications.
abstract: Sampling of a population is frequently required to understand trends and patterns in natural resource management because financial and time constraints preclude a complete census. A rigorous probability-based survey design specifies where to sample so that inferences from the sample apply to the entire population. Probability survey designs should be used in natural resource and environmental management situations because they provide the mathematical foundation for statistical inference. Development of long-term monitoring designs demand survey designs that achieve statistical rigor and are efficient but remain flexible to inevitable logistical or practical constraints during field data collection. Here we describe an approach to probability-based survey design, called the Reversed Randomized Quadrant-Recursive Raster, based on the concept of spatially balanced sampling and implemented in a geographic information system. This provides environmental managers a practical tool to generate flexible and efficient survey designs for natural resource applications. Factors commonly used to modify sampling intensity, such as categories, gradients, or accessibility, can be readily incorporated into the spatially balanced sample design.
authors.affiliation: Natural Resource Ecology Lab, Department of Natural Resource Recreation and Tourism, Colorado State University, Fort Collins, CO 80523, USA. david.theobald@colostate.edu
authors.forename: David M
authors.initials: DM
authors.lastname: Theobald
authors.forename: Don L
authors.initials: DL
authors.lastname: Stevens
authors.forename: Denis
authors.initials: D
authors.lastname: White
authors.forename: N Scott
authors.initials: NS
authors.lastname: Urquhart
authors.forename: Anthony R
authors.initials: AR
authors.lastname: Olsen
authors.forename: John B
authors.initials: JB
authors.lastname: Norman
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D003247:Conservation of Natural Resources; D040362:Geographic Information Systems; D011336:Probability; D012107:Research Design