Developing spatially explicit and stochastic measures of ecological departure

Abstract

Background Ecological departure is a metric applied to mapped ecological systems measuring dissimilarity between the distributions of observed and expected proportions of non-stochastic reference vegetation classes within an area. Aims We created spatially explicit measures of ecological departure incorporating stochasticity for each ecological system and all ecological systems from a central Nevada, USA, landscape. Methods Spatially explicit ecological departures were estimated from a radius from each pixel governed by a distance-decay function within a moving window. Variability was introduced by simulating replicate climate time series for each spatial reference condition and calculating departure per replicate. Key results Single-system spatial ecological departure was high and extensive, except for one area of low-elevation groundwater-dependent systems. Variance of spatial ecological departure was extensively low, except in areas of lower ecological departure, despite vegetation differences among replicates. The multiple-system ecological departure exhibited lower values. Conclusions Spatial ecological departure is warranted for efficient land management as results were concordant between non-spatial and spatial metrics; however, rapid coding languages will be required. Implications Spatially explicit ecological departure of both single and multiple systems facilitate localised vegetation and wildlife habitat management and land protection decisions.