Introduction

Surface Range Envelope is an envelope-style method similar to Bioclim. It is a presence-only model that uses the environmental conditions of locations of occurrence data to profile the environments where a species can be found. The envelope is defined by the minimum and maximum values of the environmental variables for all occurrences. Any location with environmental conditions that falls within this envelope is included in the potential range for a species. To avoid the over-predictive effect of outliers, the envelope can be reduced at specified percentiles or standard deviations.

Advantages

• Simple and intuitive

• Presence only model, no absence data needed

• Provides ranking of environmental predictor variables

• Useful in teaching species distribution modelling

Limitations

• Susceptible to overprediction

• Does not account for interactions between predictors

• Cannot use categorical variables

• Does not make quantitative predictions or provide confidence levels

Assumptions

The model assumes a normal distribution of the predictor variables.

Requires absence data

No.

Configuration options

BCCVL uses the 'sre' function in the ‘biomod2’ package. The user can set the following configuration options:

References

• Araujo MB, Peterson AT (2012) Uses and misuses of bioclimatic envelope modeling. Ecology 93(7): 1527-1539.

• Booth TH, Nix HA, Busby JR, Hutchinson MF (2014) BIOCLIM: the first species distribution modelling package, its early applications and relevance to most current MAXENT studies. Diversity and Distributions, 20(1): 1-9.

• Thuiller W, Lafourcade B, Araujo M (2012) Presentation manual for BIOMOD. Laboratoire d'Ecologie Alpine, Universite Joseph Fourier, Grenoble, France.