UC Davis

The shape and size of planning units (PUs) at the initial stage of regional systematic conservation planning (SCP) can strongly affect the final portfolio. In previous studies, the influence of PU shape and size has typically been considered for single study sites that include mainly natural land cover types. The impacts of PU shape and size in areas dominated by different land cover types have not been compared. We identified and compared the influence of three types of land uses, and shape and size of PUs in the efficiency of final portfolios in SCP. We show that PU shape is not significant for portfolio efficiency in all areas dominated by different land cover types, while smaller size of PUs would be more useful in the heterogeneous landscapes like agricultural and urban areas than the homogeneous landscapes like forest. We also show that the magnitude of the influences of PU shape and size differs depending on the dominant land cover type. Areas dominated by agricultural land cover were the most sensitive to the influence of PU shape and size, whereas areas dominated by forest were the least sensitive. Therefore, we recommend to planners to understand the different impacts of PU shape and size by the dominant land cover type and consider a similar approach with this study.