Introduction

The distribution of species can change over time. This map shows the locations of common beach plant species described in studies published in the academic literature at three different points in time: 1936, 1974, and 2012. The support (point or aerial representation) is based on the description by the original author.

About the Maps

Locations

The point locations on all the maps are digitized from information supplied in published papers. Cooper's (1936) locations were digitized from georeferenced scanned maps published in his paper. Because of this, the locations are presence-only observations. Each point that appears in any species' distribution is a place where the species was observed; there are no locations marked where the species was not seen. The other locations - from Purer (1936), Barbour et al. (1974), and Tobias (2012) - all display presence-absence data. In these papers, it was clear which locations each author visited and which species were found at these locations. For these data, colored markers represent locations where the species was seen and white markers represent locations without the species.

Selecting Layers

Changing the species in one map does not automatically change the species distributions in the other maps (yet). Panning and zooming is now linked between the maps. Please be patient with the navigations and layer selection and make your selections carefully.

The 1936 map has distributions from two different studies.

Watercolor Tiles by Stamen Design, under CC BY 3.0. Data by OpenStreetMap, under CC BY SA. OSM Tiles by Open Street Map under Creative Commons Attribution-ShareAlike 2.0 license (CC BY-SA). Data by Open Data Commons Open Database License (ODbL).

References

Barbour, M. G., de Jong, T. M., & Johnson, A. F. 1976. Synecology of beach vegetation along the Pacific Coast of the United States of America: A first approximation. Journal of Biogeography. 3: 55-69.

Cooper, W. S. 1936. The strand and dune Flora of the Pacific Coast of North America: A geographic study. In T. H. Goodspeed (Ed.), Essays in geobotany in honor of William Albert Setchell (pp. 141-187). Berkeley, CA: University of California Press.

Purer, E.A. 1936. Studies of certain coastal sand dune plants of Southern California. Ecological Monorgaphs. 6(1):1-87.

Tobias, M.M. 2012. California Beach Plant Biogeography: Biogeomorphology and Ecological Succession, Effects of Foot-Traffic Concentration, and Low-Altitude Aerial Photography. Dissertation. University of California, Davis.