2. Name: Southwestern Wetlands — Their Qassification and Characterization. 



Authors: David E. Brown. 



References: Brown, D.E. 1978. Southwestern wetlands — their classification and character- 

 ization, in: Proceedings of the National Riparian Ecosystems Symposium, Callaway Gardens, 

 Georgia, Dec. 1 1-13, 1978. pp. 269-282. 



Brown, D.E. and C.H. Lowe. 1973. A proposed classification for natural and potential 

 vegetation in the Southwest with particular reference to Arizona. Ariz. Game and Fish Dep., 

 Fed. Aid Proj. RpL W-53-R-22 WP^JI:l-26. 



Objectives: Provide a hierarchical structure for the worid's biotic communities based on 

 those factors most important in the evolution of origin, structure, and composition of aU 

 ecosystems, both wetland and terrestrial. Recognizes plant components within an assigned 

 ecological distribution and could lead to the species of wildlife expected to be present. 



Designed Users: Ecologists, wildlife biologists, zoologists. 



Area of Applicability: Everywhere. 



Classification Units Description, and Data: 



Classification Units 



Biogeographic 

 Realm 



Vegetation 



Formation Type 



Climate Zone 



Regional Formation 



Description 



Geographic and biologic origin-evolutionary boundaries. 

 Generally very large with the exception of small areas 

 showing high degree of endemism. Seven realms are used: 

 Nearctic (Continental North America exclusive of the tropics 

 and most highland areas south of the Tropic of Cancer); 

 Palaearctic (Eurasia exclusive of the tropics); Neotropical 

 and Antarctican; Oriental; Ethiopian; Australian; Oceanic. 



Classed as either upland wetland, or in the case of altered 

 lands, cultivated. All existing and potential natural 

 vegetation are placed in these classes. 



Refers to recognized ecological formations (biome interpre- 

 tation types). Wetland formation types include wet tundra, 

 forest, swampscrub, marshland, strand (unvegetated bank or 

 shore), and submergent. 



Refers to one of four world climate zones (arctic boreal, cold 

 temperate, warm temperate, tropical-subtropical). 



Refers to a subcontinental unit that is a major biotic commu- 

 nity (biome) usually centered in but not restricted to a 

 biogeographic region or province possessing a particular 

 precipitation pattern or other climatic regime. 



11 



