Tuesday, August 7, 2007 - 4:40 PM

COS 57-10: Reclamation of native vegetation on western post-coal-mine landscapes: Analysis, methods, and recommendations

Ken Aho and T. Weaver. Montana State University

Given the realities of coal mine and coal bed methane expansion in the Western United States effective strategies for vegetation reclamation are imperative.   It is often desirable or required by law that post-mine landscapes be reclaimed with native vegetation.  We outline a three step strategy, based on pre-mine vegetation types and their environments, to facilitate successful reclamation of native vegetation. 

(1) Identify reclamation targets using classification analyses of pre-mine vegetation.  We review a number of existing classification methods along with existing and original methods for finding the correct number of legitimate data clusters in datasets.  We demonstrate our analyses using a large (> 800 site) dataset from a pre-mine steppe landscape in Southeastern Montana. 

(2) Characterize target vegetation types.  We recognize important or dominant species in target communities to guide the creation of seed mixes.  We also recognize the role of infrequent, non-dominant species and the seral/climax character of communities in creating realistic reclamation goals and time-frames.           

(3) Model the environments of target vegetation types as a guide for landscape engineering. We found that environmental data gathered ‘on site' by consultants was generally much more precise than GIS layers or 10-30m DEMs.  We utilized two quantitative strategies to match vegetation types to their environments.  We used logistic regression to express probabilities for the occurrence of specific vegetation types given environmental responses. We also used classification and regression tree analysis as a basis for simultaneously mapping optimal vegetation types onto a post-mine surface.  While useful, the predictive power of both approaches were limited by the quality and types of environmental data gathered.