Crowley." This kind of ecological partitioning follows existing national and regional 

 schemes, whereas the basic concepts and principles of the approach were based on 

 international experiences. 



The principal agencies involved with natural resource inventories have agreed to 

 coordinate work on classification systems. Hirsch et al. have outlined the coordi- 

 nation efforts of the federal agencies under an Interagency Agreement Related to 

 Classification and Inventories of Natural Resources} 



In 1976, the Forest Service began planning for a new classification system for the 

 1990 national assessment required by the Resources Planning Act. Because of the 

 need for and interest in an interagency land classification system, several other 

 agencies, especially the Bureau of Land Management, Fish and Wildlife Service, 

 Geological Survey, and Soil Conservation Service, became involved in the develop- 

 ment of the system. These agencies are developing a single National Site (Land) 

 Classification System. The system, like ECOCLASS, is a component system. It was 

 prepared, 2'» reviewed, and tested in the field. It is based upon four relatively 

 independent components— vegetation, soil, landform. and water — organized into a 

 hierarchial classification structure (Table 2). A recent interagency review endorsed 

 the concept embodied in the system, suggested major revision in the landform and 

 water components, and noted the need for further work in relating the system to 

 mapping procedures, sampling techniques, and component integration. Also 

 identified was the need for further refinement of the vegetation component to more 

 succinctly define the linkages between climax vegetation and existing vegetation. 



Currently, the Forest Service's Resources Evaluation Techniques Program is 

 working on completion of the classification system.. -^ Included in this work is the 

 development of a process of combining (integrating) the components into a 

 hierarchial ecosystem classification scheme suitable for national assessments/ 

 appraisals, land management planning, and program planning. 



The Bureau of Land Management aggregates wildlife data according to its 

 Integrated Habitat Inventory Classification System. ^f' This classification provides a 

 six-level hierarchial system for organizing species occurrence data from the smallest 

 geographic units (special features and plant communities) to the largest units 

 (physiographic regions). At the higher classification levels, data can be crossed into 

 other classifications, including Kiichler's'* associations and Bailey's^' ecoregions. 

 Since the lowest level at which inventory data are collected is the present and 

 potential plant community, these data can be used in component classification 

 including the National Site Classification System. The Bureau of Land Management 

 is developing a classification system for aquatic wildlife habitats, in which 

 consideration is given to the Fish and Wildlife Service's wetland/aquatic classifi- 

 cation. ^"^ 



The Soil Conservation Service is basing its Resource Conservation Act assessment 

 on a classification organized around relationships which are significant to natural 

 resource use on a state and farm production region basis. This approach groups the 

 organizational geographic units related to land use, topography, climate, water, and 

 soil into Land Resource Regions and Major Land Resource Areas. ^o The collected 

 data are statistically reliable at state level aggregation. 



The Fish and Wildlife Service has developed a classification system for wetlands 

 and associated aquatic habitats which is being used to conduct the National 

 Wetlands Inventory. ^9 This system is expected to replace that developed by Martin et 

 al.,3' which has been widely utilized for wetlands management since its publication. 

 The Fish and Wildlife Service has also been developing improved approaches to 

 wildlife habitat classification for habitat other than wetlands and is working closely 

 with the other concerned agencies in developing compatible systems. 



The Geological Survey's Land Use and Land Cover Mapping Program" provides 

 broad-based information. Although it is not intended for wildlife habitat classifica- 

 tion, the USGS program can assist in interpreting wildlife habitat information. 



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