| Abstract: | Research efforts studying dune fields as spatial units are limited and the historical dynamics associated with dune field-scale pattern attributes are currently not well documented. Historical repeat aerial photography was used to quantify temporal changes in the crescentic dune pattern at the White Sands Dune Field, New Mexico. A Geographic Information System (GIS) was used to digitize ~ 14,000 dune crests from the combined photoset. Crest length, sinuosity, spacing, orientation, transport vector, and defect density were calculated from these measurements and statistically analyzed. The pattern analysis revealed that crest length, sinuosity, and defect density were highly variable pattern elements over a 60-year period. These dune pattern elements also exhibited temporal relationships, such as the inverse relationship between crest length and sinuosity over time. Defect density calculations revealed that the dune field is trending to a possible state of disorganization. This trend was temporarily interrupted in 1985 by a massive period of organization in which crest length was inversely related to defect density and defect density was proportionally related to sinuosity. The temporal variations in these pattern elements and the episodic organizational event in 1985 were likely climatically induced. |
