Repeat Photography

Source: Allen, C. D., J. L. Betancourt, and T. W. Swetnam. 1995. "LUHNA Pilot Project - Southwestern United States." [http://biology.usgs.gov/luhna/chap9.html]. 7/6/99.

Repeat photography is a simple and inexpensive tool for reconstructing past environmental changes and monitoring future ones; it is particularly well suited for the relatively open landscapes of the western U.S. As a first approximation, past environmental change can be measured by finding the site of a historical photograph, reoccupying the original camera position, and making a new photograph of the same scene. Differences between then and now provide a basis for identifying and even quantifying changes, while the new photograph establishes a benchmark for future evaluation.

As photography was introduced in the West just after the Civil War and did not come into general use until the 1880s, many of even the earliest photographs are too recent to show conditions before heavy use of the area by stock. But at least some idea of the relative dominance of shrubs, herbs, or grasses can be gained even when the exact species cannot be determined.

Rephotography in the southwest has focused on key ecological concerns relevant to management of public lands, including shrub and tree encroachment upon grasslands, climatic effects on demographic trends in woodlands, post-disturbance histories (see photos below), and geomorphic, hydrologic and vegetation changes in riparian areas.

Fire suppression could explain the shifting of local ecotones, for example as shown in H. E. Gregory's 1920s (top) and Ray Turner's 1988 (bottom) photographs of Bear's Ears in southeastern Utah. Note the expansion of mixed conifer forest, including Douglas-fir, white fir, and ponderosa pine from Bear's Ears down to level terrain of Elk Ridge.

Where have all the grasslands gone? Numerous ecological studies across the Southwest have documented the decline in herbaceous vegetation (grasses and non-woody flowering plants) while forests thicken and brush invades. Documenting the changes in the Jemez Mountains of northern New Mexico, ecologist Craig Allen considers the evidence that these patterns are tied to changes in land use history, primarily livestock grazing and fire suppression.

Anonymous. No date. Vegetation changes on the Manti-LaSal National Forest: A photographic study using comparative photographs from 1902-1992. USDA Forest Service, Manti-LaSal National Forest, Price, Utah.

Allen, C. D., J. L. Betancourt, and T. W. Swetnam. 1995. "LUHNA Pilot Project - Southwestern United States." [http://biology.usgs.gov/luhna/southwest/southwest.html]. 7/6/99.

Arnold, J. F. 1950. Changes in ponderosa pine bunchgrass ranges in northern Arizona resulting from pine regeneration and grazing. Journal of Forestry 48: 118-26.

Arnold, J. F., D. A. Jameson, and E. H. Reid. 1964. The pinyon-juniper type of Arizona: Effects of grazing, fire and tree control. Forest Service Production Research Report, U.S. Department of Agriculture.

Baars, D. L., and C. M. Molenaar. 1971. Geology of Canyonlands and Cataract Canyon. Guidebook, 6th Field Conference, Four Corners Geological Society, Durango, CO.

Baars, D. L. 1973. Geology of the canyons of the San Juan River. 7th Field Conference, Four Corners Geological Society, Durango, CO.

Buchanan, H. 1971. Changing conditions in the forests of Bryce Canyon National Park, Utah. Pp. 31-36 In: Proceedings of the Utah Academy of Sciences, Arts, and Letters, pt. 1. Volume 48. Utah Academy of Sciences, Arts, and Letters, Provo.

Cooper, C. F. 1960. Changes in vegetation, structure, and growth of southwestern pine forests since white settlement. Ecological Monographs 30: 129-164.

Covington, W. W., and M. M. Moore. 1994. Southwestern ponderosa forest structure: Changes since Euro-American settlement. Journal of Forestry 92: 39-47.

Dolan, R., A. Howard, and A. Gallenson. 1974. Man's impact on the Colorado River in the Grand Canyon. American Scientist 62: 392-401.

Dutton, A. A., and D. T. Bunting. 1981. Arizona then and now: A comprehensive rephotographic project. Ag2 Press, Phoenix, AZ.

Frischknecht, N. C., and L. E. Harris. 1968. Grazing intensities and systems on crested wheatgrass in central Utah: Response of vegetation and cattle. Forest Service Technical Bulletin 1388, U.S. Dept. of Agriculture, 47 pp.

Gordon, B. R., G. P. Parrott, and J. Smith. 1992. Vegetation changes in northern Arizona: The Alexander Gardner photos. Rangelands 14.

Graf, W. F. 1978. Fluvial adjustment to the spread of tamarisk in the Colorado Plateau region. Geological Society of America Bulletin 89: 1491-1501.

Graf, W. L. 1983. Downstream changes in stream power in the Henry Mountains, Utah. Annals of the Association of American Geographers 73: 373-87.

Hastings, J. R., and R. M. Turner. 1965. The changing mile: An ecological study of vegetation change with time in the lower mile of an arid and semiarid region. University of Arizona Press, Tucson, AZ.

Johnsen, T. N., Jr., and J. W. Elson. 1979. Sixty years of change on a central Arizona grassland-juniper woodland ecotone. Agricultural Reviews and Manuals ARW-M-7, U.S. Department of Agriculture Science and Education Administration.

Leopold, L. B. 1951. Vegetation of southwestern watersheds in the nineteenth century. The Geographical Review 41: 295-316.

Malde, H. E. 1973. Geologic benchmarks by terrestrial photography. U.S. Geological Survey Journal of Research 1: 193-206.

Pearson, G. A. 1950. Management of ponderosa pine in the southwest. U.S. Dept. of Agriculture Monograph 6: 218.

Peterson, K. L., and P. J. Mehringer. 1976. Postglacial timberline fluctuations, La Plata Mountains, southwestern Colorado. Arctic and Alpine Research 8: 275-88.

Phillips, W. S. 1963. Vegetational changes in northern Great Plains. Report 214, University of Arizona Agricultural Experiment Station, Tucson.

Potter, L. D., and J. C. Krenetsky. 1967. Plant succession with released grazing on New Mexico range lands. Journal of Range Management 20: 145-51.

Rogers, G. F. 1982. Then and now: A photographic history of vegetation change in the central Great Basin Desert. University of Utah Press, Salt Lake City.

Rogers, G. F., H. E. Malde, and R. M. Turner. 1984. Bibliography of repeat photography for evaluating landscape change. University of Utah Press, Salt Lake City.

Shaw, H. G., and M. L. McCrosky. 1995. Historic photographs of central Arizona grasslands and associated habitats. Sharlot Hall Museum, Prescott, AZ.

Shoemaker, E. M., and H. G. Stephens. 1975. First photographs of the Canyon Lands. Pp. 111-222 In: J. E. Fassett, editor. Canyonlands country: Four Corners Geological Society Guidebook. Four Corners Geological Society, 8th Field Conference, Durango, CO.

Swetnam, T. W., C. D. Allen, and J. L. Betancourt. In press. Applied historical ecology: Using the past to manage the future. Ecological Applications.

Turner, R. M., and M. M. Karpiscak. 1980. Recent Vegetation Changes Along the Colorado River Between Glen Canyon Dam and Lake Mead, Arizona. USGS Prof. paper 1132. pp 125.

Turner, R. M., L. H. Applegate, P. M. Bergthold, S. Gallizioli, and S. C. Martin. 1980. Arizona range reference areas. General Technical Report RM-79, USDA Forest Service, 34 pp.

USFS. 1994. Vegetation changes on the Manti-La Sal National Forest: A photographic study using comparative photographs from 1902-1992. USFS, Intermountain Region, Price, UT.

Webb, R. H., S. S. Smith, and V. A. S. McCord. 1992. Historic channel change of Kanab Creek, southern Utah and northern Arizona, 1991. Grand Canyon Natural History Association, Grand Canyon, AZ.

Webb, R. H. 1996. Grand Canyon, a century of change: Rephotography of the 1889-1890 Stanton Expedition. University of Arizona Press, Tucson, AZ.