Stable Grassland Ecosystem
This file was created by scanning the printed publication. Errors identified by the software have been corrected; however, some errors may remain. Chapter 5 Desert Grassland and Shrubland Ecosystems Samuel R. Loftin, USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Albuquerque, New Mexico Richard Aguilar, Sandia National Laboratories, Albuquerque, New Mexico Alice L. Chung-MacCoubrey, USDA Forest Service, . Rocky Mountain Forest and Range Experiment Station, Albuquerque, New MexIco Wayne A. Robbie, USDA Forest Service, Watershed an~ Air Management Staff, Region 3, Albuquerque, New MexIco INTRODUCTION taken from a review by Dick-Peddie (1993). The ex tensive grasslands and shrublands of North America The productivity, stability, and health of the Middle developed in response to climate change and the Rio Grande Basin, arid and semiarid grassland and uplifting of the western mountain ranges, includ.ing shrub land ecosystems depend upon complex inter the Rocky, Cascade, and Sierra Nevada Mountains, actions. These relationships occur between factors which began in the early to mid-Tertiary period (65- such as climate, domestic livestock, and wildlife use, 26 million years ago). The vegetation of North and human activities such as urban development, ag America early in the Tertiary period has been riculture, and recreation. These grassland/ shrubland grouped into three major geoflora.s. The Artc~ ecosystems are particularly sensitive to change because Tertiary Geoflora occupied cool, mOIst, upper latI they depend highly upon water availability. tudes, the Neotropical-Tertiary Geoflora occupied the Southwestern rangelands experienced heavy live warm, moist,lower latitudes, and the Madro-Tertiary stock grazing and human activities over the past cen Geoflora occupied intermediate, drier regions.
[Show full text]