Recipient Organization
Primordial Solutions, Inc.
(N/A)
Grand Junction,CO 81501
Performing Department
(N/A)
Non Technical Summary
The soils in arid environments of the Western United States are experiencing increasing pressure from mining, energy extraction, ranching, and population. These pressures lead to erosion, landscape degradation, and reduced biodiversity, that is shortly followed by unsustainable environments and degraded economies. The purpose of this project is to examine the factors that promote the reestablishment of the native photosynthetic microorganisms that are responsible for regulating the fertility and productivity arid ecosystems.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Goals / Objectives
The loss of soil through erosional forces leads to landscape degradation, diminished primary productivity, and reduced biodiversity. These losses result in unsustainable environments and economic poverty. Erosion control techniques are usually designed to establish vegetation in order to hold the soil in place. Various soil amendments such as fertilizers, mulches, glues, and geo-textiles are commonly used to promote the development of dense vegetative cover. However, the meager precipitation in arid ecosystems of the Western United States, are unable to support dense vegetative cover. Consequently, attempts in establishing dense vegetative cover rarely succeed, and cost-effective alternatives are needed. This is especially important in arid public lands where mining, energy extraction, and ranching are degrading these delicate ecosystems. Our objective is to demonstrate and validate an emerging technology that is designed to repair degraded soils in arid environments.
Our technology is based on the observation that arid ecosystems are dominated by photosynthetic microbial communities. Instead of dense stands of vascular plants, arid ecosystems are dominated by photosynthetic microbial communities that represent up to 70% of the living cover. These microbial communities are often dominated by nitrogen-fixing cyanobacteria, lichens, that in turn, support beneficial fungi and bacteria. These communities hold the soil in place, secrete nitrogen fertilizer, improve water relation thus improving soil fertility and enhancing biogeochemical cycles. This enhanced fertility support vascular plants to create sustainable arid ecosystems. Historically, these photosynthetic microbial communities have been called cryptogamic crust, microphytic soils, or more recently, Biological Soil Crust (BSCs). Despite the fundamental importance of BSC communities in desert ecosystems, they are just as susceptible to disturbance as the vascular plants, and are similarly slow
to recover. Estimates of recovery range from 20 to 3800 years depending on various environmental factors. As population pressure and human impact in the Western United States steadily increases, it becomes increasingly desirable to have a technology to ameliorate these impacts. This research intends to accelerate the recovery of BSC communities, and in turn facilitates the establishment and vigor of the sparse native vascular flora. We accomplish this goal by isolating the important crust-forming nitrogen-fixing cyanobacteria from the disturbed area, mass producing these organisms, and applying the microbial mixture to disturbed soils.
Project Methods
We are developing an approach that is intended to exploit the desirable ecological attributes of Biological Soil Crusts. The idea is simple, but the implementation requires the arts of microbiology, ecology, biochemistry, and engineering. First, colonized soils adjacent to the disturbed area are collected and the cyanobacteria are cultured. The resulting culture reflects the species composition of the native cyanobacterial community. The advantage of this approach is that the pre-adapted native microorganisms are used to remediate the given area. This approach is similar to using the native ecotypes of particular plant species. On the other hand, several cyanobacterial species are found in all North American deserts and it is currently unknown whether these entities are significantly different from one area to another. We therefore choose to err on the side of caution and cultivate organisms from adjacent areas. Second, the multi-species culture is mass-produced in a
photobioreactor. The physical and chemical conditions are manipulated to promote rapid growth and the development of nitrogen-fixing heterocysts. In addition, we manipulate the culture to induce the production of photoprotective pigments. The pigments, scytonemin and mycosporine-like amino acids (MAAs) absorb ultraviolet radiation in the UV-B range to protect the cells from DNA damage and photoxoidation. The induction process helps to ensure the survival of the cells during the early stages of soil colonization. Third, the cells are periodically harvested from the photobioreactor, air dried, and ground into a powder to facilitate dispersal. These desert adapted cyanobacteria are well known for desiccation tolerance where the cells remain viable following repeated cycles of hydration and dormancy when dehydrated. During drying, these organisms produce water stress proteins (WSPs) and various solutes that stabilize membranes to reduce membrane leakage upon re-hydration. If more carbon
resources are leaked than are produced during the short periods of hydration, the cell will die. Since we believe that the cells are most vulnerable when initially applied to the soil, we add xeroprotectant compounds to the cells prior to our air drying process. This research will lead to a renewable, self-sustaining, photosynthetic biofertilizers that improves the fertility of disturbed arid soils. Application of the biofertilizers is expected to either replace or supplement current revegetation techniques. Deployed cyanobacterial inoculants stabilize the soil, contribute fixed nitrogen and carbon, and increase soil moisture. Since the biofertilizers is alive, these attributes improve with time and enhances the productivity and nutritional value of the native vascular vegetation. Taken together, this new industry will benefit environmental restoration, mining, energy extraction, and livestock industry. Finally, the productivity and economic health, managed by the USDA and USDI, will
benefit.