|
|
The manual zoom transfer scope is a device that allows for simultaneous viewing and scale matching of a variety of sources (such as aerial photos, plats, and surveys) to a georeferenced base map, such as a U.S. Geological Survey topographic map. After the zoom lens is used to adjust for scale differences, data can be transferred (traced) to a stable base overlay (such as mylar or acetate) and digitized by using a geographic information system.
|
The geographic information system pilot project on Pool 13 of the Upper Mississippi River System was initiated to evaluate system-wide application of various methods of capturing, processing and converting resource data. Classification schemes were developed for two data themes: land cover/land use (vegetation) and aquatic areas. Evaluation of 1:15,000 scale aerial photography indicated that (1) color infrared transparencies were essential for accurately mapping major vegetation classes and vegetation units less than 1 acre; (2) color infrared prints were essential for field work (delineating work areas on the photos and identifying in the field; (3) true color (Ektachrome) transparencies and prints were not useful...
|
The Upper Mississippi River System (UMRS) is physically diverse and biologically productive, providing habitat to hundreds of species of plants and animals. Aquatic and terrestrial plant communities provide structure, food, and shelter to a variety of organisms, influence nutrient dynamics and water quality, and stabilize sediments (Sculthorpe 1967; Wetzel 1983). Although aquatic and terrestrial vegetation have important ecological value, there are few long-term studies directed toward understanding spatial and temporal changes or understanding potential factors influencing this important component.
|
An experiment to improve ecological conditions while maintaining a 9-foot (2.74-m) navigation channel was continued in 1995 and 1996 on the three pools of the Upper Mississippi River managed by the St. Louis District, U.S. Army Corps of Engineers. Water levels were held from 1 to 3 feet (0.3 to 0.9 m) lower than maximum regulated elevations at the dam from about mid-June through July in Pools 24 and 25 and Melvin Price Pool. Water levels were then gradually raised as discharge allowed. Vegetation was surveyed along an elevational gradient in eight areas in 1995 and six areas in 1996. Seven plant genera were identified in 1995 and five genera in 1996. Amaranthus spp. (pigweed), Cyperus spp. (chufa), Echinochloa spp....
|
The Environmental Management Technical Center hosted the first Upper Midwest Gap Analysis Workshop to initiate the coordination and implementation of Gap Analysis in the states of Minnesota, Michigan, and Wisconsin. Presently, Gap Analysis projects are being completed on a state-by-state basis, depending on level of interest and need by each state. Because Gap Analysis provides a standardized method and format, as state projects are completed the data can be edge-matched with adjacent states to reveal actual patterns of biodiversity at scales relevant to both the magnitude of present-day changes and the multiple levels of biological organization. Gap Analysis products are being used by state and local governments,...
|
View more...
|
