The Beartooth Butte Formation is found in many mountain ranges throughout central Montana and northern Wyoming. This study combines a variety of geologic data to provide a clearer understanding of the fossil fauna and environmental setting of this rock unit.
The successful restoration of riparian ecosystems to sustainable conditions requires that we understand the dynamic historical relationships between humans and the environment. Research is needed that measures the continuing effects of past human activities on contemporary ecosystem structure and function. An interdisciplinary approach is needed that incorporates expertise from archaeology, paleoecology, plant ecology, and geology.
The 51 papers in this proceedings include an introductory keynote paper on ecotones and hybrid zones and a final paper describing the mid-symposium field trip as well as collections of papers on ecotones and hybrid zones (15), population biology (6), community ecology (19), and community rehabilitation and restoration (9).
Analyses of water- and sediment-yield records from the Walnut Gulch Experimental Watershed, the San Simon Wash Basin, and the Jornada Experimental Range, combined with observations of regional variations in climate, geology and soils, vegetation, topography, fire frequency, and land-use history, allow estimates of present conditions of water and sediment discharges in the upper Animas Creek Basin, New Mexico.
Ecological units are described at the subsection level of the Forest Service National Hierarchical Framework of Ecological Units. A total of 91 subsections are delineated on the 1996 map "Ecological Units of the Northern Region: Subsections," based on physical and biological criteria. This document consists of descriptions of the climate, geomorphology, geology, vegetation, and soils that characterize each subsection.
The Middle Rio Grande (MRG) riparian forest, or "bosque", represents the largest cottonwood gallery riparian forest in the southwestern United States. This reach of the Rio Grande extends from Cochiti Dam downstream 260 Km to San Marcial, New Mexico. It constitutes 8% of the river’s total length and 34% of if its length in New Mexico. The valley traverses three major biotic communities, as defined by Brown and Lowe (1980).
There are two experimental forests in Montana established by the U.S. Department of Agriculture, Forest Service, Intermountain Research Station (INT). Both experimental forests are administered by INT's Research work Unit, RWU-4151, Silviculture of Subalpine Forest Ecosystems.
The Middle Rio Grande is part of the chain of structural basins, known as the Rio Grande depression, that extends from the San Luis Valley in Colorado to El Paso, Texas, and through which the Rio Grande flows (Chapin and Seager 1975). Bryan (1938) is credited with designating this reach as the Rio Grande "depression," because of his early research and the level of understanding he provided on the geology of the region.
Air quality is monitored continuously at GLEES. Air pollutants are considered an important component of the atmosphere that can have an effect on terrestrial and aquatic ecosystems. Atmospheric deposition of gases, wet deposition of chemicals in precipitation including snow and rain, and dry deposition of chemicals are all monitored at GLEES. Although GLEES is a relatively remote and unpolluted site, deposition of pollutants can be important.
This appendix provides a list of 230 vascular plant taxa that were field identified and/or collected over the period 1986-1990. Field identification was done by C.L. Simmons in 1986-87 (see Chapter 2). Subsequent taxa were field identified, collected, and verified by J.D. Haines and C.M. Regan in 1988-90. Voucher specimens were verified by taxonomists at the Rocky Mountain Herbarium.