Because legumes are critical to reclamation and restoration of nutrient-poor sites, we need to understand the mechanisms involved in their establishment.  Of key importance is defining and identifying what abiotic and biotic factors inhibit or facilitate colonization and growth over time.  The aim of this study was to determine the effect of rhizospheric microbial communities on nutrient acquisition by Lupinus diffusus, a colonizer of recently disturbed sites.  In addition, the study attempted to verify how seasonal trends affect microbial communities and nutrient availability.

Results/Conclusions

We used multiple regression to examine correlations between site specific environmental variables and the number of viable microorganisms per treatment.  The environmental variables (percent soil moisture, percent organic matter, and total mineral nitrogen) failed to explain a significant amount of the variation in the low enrichment culture method that was used.  This trend may be due to the already low amounts of nitrogen, and organic matter as well as the climatic nature of the region. However, increasing Phosphorus levels were associated with a decrease in colony forming units (CFUs). We hope that further exploration of the data will help to explain the results obtained.