Development of Photosynthetic Nitrogen-Fixing Biofertilizers for Arid Land Reclamation

NON-TECHNICAL SUMMARY: The major challenges faced by vascular plants, in the context of arid land reclamation, include erosion, limiting levels of water, nutrients, and competition by exotic annual grasses. In arid ecosystems throughout the world, biological soil crusts (BSCs) have been shown to either reduce or eliminate these challenges. BSCs are formed by a complex microbial community consisting of nitrogen-fixing cyanobacteria and cyanolichens intermingled with fungi, eukaryotic algae, bacteria and bryophytes, that stabilize the soil, contribute fixed nitrogen, and increase moisture levels. However, their recovery rate is slow (ranging from 5 to 3,800 years) following major disturbances, such as fire, mining, over-grazing, and human recreation. This research will lead to a renewable, self-perpetuating, photosynthetic, nitrogen-fixing biofertilizer designed to improve the quality of disturbed arid soils. Single soil applications are expected to achieve dramatic improvements in soil stability and fertility based on the biofertilizer's self-propagating photosynthetic capabilities. Additional benefits include carbon dioxide sequestration and reduced agricultural nitrate pollution, as well as a strong potential as a drought-tolerant cover crop. This new industry will economically benefit environmental restoration companies, the mining industry, the livestock industry, and recreation trade. It will also benefit the US Department of the Interior and the US Department of Agriculture, federal agencies responsible for the stewardship of our public lands.