Air photointerpretation and satellite imagery analysis techniques for mapping cattail coverage in a northern Everglades impoundment

Color-infrared aerial photography taken in 1991 and 1995, and SPOT satellit e imagery taken in 1991, Miere utilized to create cattail coverage maps for Water Conservation Area 2A (WCA2A), an impounded portion of the remnant Ev erglades. Cattail stands were delineated and classified using conventional air photointerpretation and digital image processing techniques, respective ly. Four interacting confounding factors (i.e., water depth/color, impacts from fire, periphyton species composition, and growth morphology within a s ingle species) are implicated as possible elements that complicated vegetat ion classification. Photointerpretation techniques showed an increasing tre nd in cattail encroachment from 421.6 hectares of monotypic cattail in 1991 to 1646.3 hectares in 1995. A 1991 SPOT classified image appears to have o verestimated cattail coverage due to the interacting confounding mechanisms . Overall accuracies for 1995 air photointerpreted map and 1991 SPOT classi fied image were 95.2 and 83.4 percent, respectively.