2002-07-08_GENERAL DOCUMENTS - M2002004 (3)

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plant communities and landscapes following mining. We also review the soil handling and reclamation plans at selected mine sites and critique the regulatory constraints that guide reclamation toward uniformity. Baseline soils and vegetation data are the best means to decipher the intrinsic diversity of a native landscape and identify gradients that may increase reclamation diversity. Examination of the physical and chemical variability of soils that influence premine plant communities can assist in the development of reclamation plans that may produce greater diversity. To illustrate how baseline data might be used to help design a diverse and beneficial post - mine landscape, we consider a current case in northwest New Mexico. The Bureau of Land Management recently changed the land use in the vicinity of an active coal mine to exclude grazing and improve mule deer winter range. The original reclamation plan developed by the mine operator for a grazing post -mine land use must now be revised for wildlife exclusively. This presented an opportunity to consider alternative reclamation methods that could potentially create more post -mine diversity and support wildlife. The premine toposequence illustrates the relationship between genetic soil (A & B horizons) depth and differing plant communities (Figure 1). The Pinon - Juniper woodland was a major premine community found on shallow, gravelly soils on ridges and shoulder Sage Grassland slopes. Portions of the P -J type were chained in 1961, and these areas subsequently ustollic Orchids ids Ustic Tarn wants Ustollic developed into highly diverse mixed -shrub communities. Moving downslope, Sagebrush- grassland and Grassland communities occupied deeper Aridisols of alluvial fans and upland valleys. In upland drainages, arroyos, and swales, deep alluvial Fluvents support shrubland communities of greasewood and sagebrush. Similarities between the premine plant communities are given in Table 1. Despite the moderately high level of similarity as measured by Sorenson's (1948) Index, when one views the premine landscape it is easy to discern the different plant communities. This physiognomic P -J Chained Grassland Sage Grassland Greasewood /Sage PREMINE LANDSCAPES & DIVERSITY 0.70 0 47 0.66 0.64 Pinyon- Juniper & P -J Chained I.ithic Torriorthents Figure 1: Toposequence of premine soils and associated plant communities in NW New Mexico. Genetic soil (A & B horizons) are indicated by clear Table 1: Sorenson's Index of Similarity for premine plant communities in NW New Mexico Plant Community Pinon- Juniper P -J Chained Grassland Sage Grassland 0.53 0.61 0.55 0.67 GreasewoodlSage 0.62 0.76 diversity is certainly what most reclamationists would like to recreate, but we must recognize that the species differences are not that extreme. Sage Grassland