Recipient Organization
UNIVERSITY OF WYOMING
1000 E UNIVERSITY AVE DEPARTMENT 3434
LARAMIE,WY 82071-2000
Performing Department
Ecosystem Science and Management
Non Technical Summary
This proposal addresses use of carbon-rich soil amendments to manipulate nutrient cycling by stimulating microbial immobilization of plant available nutrients. This practice has been shown to suppress weeds, many of which metabolize available nitrogen more rapidly than native species, increase biomass of native plants, and increase soil organic matter content. The research proposed here would translate this contemporary body of basic ecological research from natural plant communities at risk of weed invasion to practical application on reclaimed sites were disturbance releases a pulse of plant-available N and significantly reduces SOM content, both of which facilitate weed invasion and make restoration of native sagebrush-steppe vegetation difficult. Reclamationists and weed control agents in Wyoming need guidelines for using C-rich amendments available from farmlands and forest management practices near energy extraction sites. Forest and habitat managers also need information on whether they can promote use of woody waste materials for reclamation. We propose to implement parallel field and greenhouse studies at the Pinedale Anticline and Jonah natural gas well fields and the UW Laramie Research and Extension Center greenhouse to evaluate high, medium, and low rates of materials with a range of quality, including conifer wood chips (C:N ~ 588), wood chips plus compost (C:N ~ 300), and wheat straw (C:N ~ 187). Rates are based on values reported to effectively immobilize N in other environments and on reclamationists' judgments about economic and logistical feasibility, and include a high rate providing about 16,000 kg C ha-1 and a low rate providing about 3200 kg C ha-1, equivalent to about 15 and 3 tons per acre of wood chips, respectively. Field experiments will be laid out in a randomized complete block design with four replications of eight treatments plus a control on 10- x 15-foot plots (80 plots total at two sites with 3 treatments plus control x 4 reps x 2 sites). The greenhouse experiment will be established in two-liter pots and will include soils from the two field study sites plus one more saline site. The experiment will be laid out in a randomized complete block design with four replications of three pots for each treatment: one each with a native grass, a native forb, and a noxious weed representative of vegetation at each field site 360 pots total). Data collected will include basic soil quality parameters plus dynamic SOM and microbial community parameters from both the field and greenhouse studies; vegetation cover and biomass; and economic parameters for assess cost-benefit ratios. The research addresses both basic and applied questions and we expect information compiled to support future funding for basic research on restoration ecology and soil development following disturbance, as well as for development of more comprehensive guidelines on organic amendments funded by energy companies and the School for Energy Resources. This work will produce an MS thesis, peer-reviewed journal articles, a UW CES peer-reviewed bulletin, and presentations at scientific meetings and reclamation workshops.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Goals / Objectives
Our goal is to determine the value of C-rich materials available to Southwestern Wyoming reclamationists as soil amendments for difficult-to-restore semiarid plant communities. 1. Determine effects of the C-rich amendments on soil properties that support reclamation. 2. Determine effects of the C-rich amendments on weed infestation and success of reclamation seedings. 3. Determine economic feasibility of using C-rich amendments with respect to their efficacy as a reclamation tool and their overall costs compared to standard procedures. Expected outputs include: 1. Peer-reviewed scientific publications in Rangeland Ecology & Management or Restoration Ecology; 2. One peer-reviewed UW CES (University of Wyoming Cooperative Extension Service) bulletin; 3. Presentations at at least three of the following: a. 2011 or 2012 American Society of Mining and Reclamation annual meeting; b. 2012 Soil Science Society of America annual meeting; c. CES reclamation workshops; d. 2012 Wyoming Reclamation and Restoration Center symposium e. 2011 or 2012 Petroleum Association of Wyoming Reclamation workshop.
Project Methods
Field plot evaluations will be established at the Pinedale Anticline (ecological site = loamy 10-14" precip) and Jonah gas well fields (ecological site = shallow loamy, 7-9" precip). Both plot studies will be established on recently reclaimed well pads adjacent to identically managed sites utilized in our ongoing research on soil C and N dynamics during development and reclamation of natural gas well pads. Field treatments will be established in a randomized complete block design with four replications at each of the two study sites. Treatments include (dry-weight basis): 1) Control; 2) straw, rate 1: 2.2 Mg ha-1; (1.0 ton acre-1); 3) straw, rate 2: 6.7 Mg ha-1 (3.0 tons acre-1); 4) straw, rate 3: 11.2 Mg ha-1 (5.0 tons acre-1); 5) wood chips, rate 1: 2.9 Mg ha-1 (3 tons acre-1); 6) wood chips, rate 2: 19.2 Mg ha-1; (9 tons acre-1); 7) wood chips, rate 3: 32.0 (14.25 tons acre-1); 8) wood chip/compost mix, rate 1: 3.6 Mg ha-1 (1.6 tons acre-1); 9) wood chip/compost mix, rate 2: 10.7 Mg ha-1 (4.8 tons acre -1); 10) wood chip/compost mix, rate 3: 17.8 Mg ha-1 (7.9 tons acre -1); Soil properties, soil organic matter pools, and microbial community changes will be monitored from three sampling events (fall, late spring, fall). Vegetation canopy cover by species will be recorded at peak growth and at the end of the growing season in year two. A parallel greenhouse pot study will be established in early 2011 at the research greenhouse at the UW Laramie Research and Extension Center in greenhouse space to be reserved for this project. The greenhouse pot study will mirror the field studies utilizing topsoils (0- to 15-cm depth) collected at each of the field study sites plus from saline site (Wamsutter, ecological site = saline upland, 7-9" precip.). One native forb and one native grass shared among the seeding mixes associated with each field study area, plus one annual invasive weed to be identified in conjunction with collaborators (i.e., halogeton [Halogeton glomeratus (M. Bieb.) C.A. Mey.] Russian thistle [Salsola kali L.], or others) will be included in the greenhouse studies. We will establish four replicate pots of each plant species, ecological site, and soil amendment combination for a total of 360 total pots arranged in a randomized complete block design in the Laramie Research and Extension Center Greenhouse. Emergence and growth of seeded species will be monitored. The well pads with the C amendments will be compared to standard reclamation procedures in terms of the costs and re-vegetation benefits. The value of the benefits will be assessed in terms of forage and wildlife habitat. C additions will be ranked by economic attributes such as: 1) cost of material; 2) transportation and application; 3) labor; 4) local and consistent availability; and 5) ecological contribution. We will develop a cost/benefit figure for each plot based on the results of the cost analysis and the soil and vegetation monitoring. We will use this to determine whether there are advantages to using additions that offset increased costs, and, if there are advantages, what the thresholds are based on the benefits of the treatments.