Progress 01/01/03 to 09/30/08
Outputs
OUTPUTS: The objectives of this project were met through the integration of data collected from both controlled greenhouse experiments and randomized field trials. A greenhouse experiment was conducted to quantify soil carbon enrichment via rhizodeposition from loblolly pine seedlings. Trends were observed for plant photosynthate allocation in roots and foliage as a function of fertilization and soil texture (sand or loam soil). Fertilization resulted in a reduction in the proportion of photosynthate allocated to loblolly pine seedling roots relative to aboveground allocation. Additionally, the effect of fertilization on overall biomass growth as well as carbon allocation above and below ground was more pronounced in sand textured planting media. Field trials of the effects of organic fertilization (poultry litter) on soil and water chemistry yielded results that suggest more nitrate ends up in soil and surface waters in pastures than in forests. Due to the interrelationship of the biogeochemical cycle of carbon with nitrogen, all experiments in this project quantified nitrogen as well as other physical and chemical parameters known to influence changes in soil carbon. Estimates of nitrogen mineralization potentials were conducted following aerobic incubations, and the results of these procedures suggest that litter applications may differentially alter the microbiota in pasture and forest soils, resulting in changes in rates of mineralization and nitrification. Changes in mineralization potentials appear to be linked with the trends observed in both soil and runoff waters. To address the objectives outlined in this project, accurate determination of carbon and nitrogen contents in soils was essential. This need is common to researchers around the globe. Standardized soil samples are very limited in supply and are very expensive, so a substitute was needed. I created and tested a compound that behaves as a mineral soil sample in dry combustion analyzers. The main advantages of this compound include low cost and the ability to customize the concentration of carbon and nitrogen in samples that are being used for machine calibration or quality control check samples. A study was conducted in the Ozark Highlands to study of the relationships between soil fertility, forage quality, and foliar spectral signatures. The results of this investigation provide evidence that the use of near infrared reflectance spectroscopy (NIRS) coupled with multivariate modeling may be effective for rapidly and accurately quantifying the physical and chemical properties of soils. In addition to using NIRS analyses of soil properties, it was found that Vaccinium spp. foliage was significantly correlated with soil C, N, Ca, pH, and P, and spectral data explained more than fifty percent of the variation in soil nutrient content. By increasing the size of the spectral database is should be possible for researchers and resource managers to utilize NIRS technology for expediting biogeochemical characterizations of plant and soil samples. PARTICIPANTS: M. Blazier, LSU Agriculture Center, Baton Rouge, LA R.I. Dresbach, Civil and Environmental Engineering, University of Missouri R.E. Kissell, Jr., School of Forest Resources, University of Arkansas at Monticello H.O. Liechty, School of Forest Resources, University of Arkansas at Monticello S.R. Mehmood, School of Forest Resources, University of Arkansas at Monticello D. Patterson, School of Forest Resources, University of Arkansas at Monticello M. Pelkki, School of Forest Resources, University of Arkansas at Monticello J. Schuler, School of Forest Resources, University of Arkansas at Monticello M.G. Shelton, USDA Forest Service, Southern Research Station H.C. Stuhlinger, School of Forest Resources, University of Arkansas at Monticello TARGET AUDIENCES: Forest Landowners Environmental Researchers Soil Scientists Ecologists Atmospheric Scientists Farmers PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Based upon the results of this project, a new project has been initiated to further develop near infrared reflectance spectroscopic (NIRS) models for characterizing soil chemical and physical properties. By establishing field studies in areas mapped as the same soil map unit, it is hoped that soil characteristics identified in the soil survey can be used as proxies for estimating soil carbon enrichment by loblolly pine. Identification of suitable proxies should make site characterization work in the future more cost effective. The quantification of soil carbon enrichment via loblolly pine rhizodeposition provided data suitable for modeling potential soil carbon sequestration in loblolly pine plantations. Given the importance of intensive silviculture in Arkansas and the valuation of carbon sequestration, the experiments conducted for this project provided a critical component for comparing the effects of different forest management practices on the sequestration of atmospheric carbon. The data from the organic fertilization study in pine stands and pastures have profound implications for Arkansas. Disposal of litter is a serious problem, as many pastures that have been used for litter disposal are becoming saturated with nitrogen. Applications of nitrogen in excess of the capacity for the soil or vegetation to absorb the nitrogen result in a site becoming a source rather than a sink. From a nitrogen management perspective, forest soils were found to be effective sinks for litter disposal; however, the number of applications that forest soils can receive without creating environmental problems is unknown. In a broader context, the carbon-nitrogen compound developed for dry combustion analyzers has garnered attention from researchers and laboratory managers across the country and around the globe. This impact was secondary to the primary objectives of this project; however, this outcome is among the most significant of this entire project in terms of reach.
Publications
- Liechty, H.O., M.A. Blazier, J.P. Wright, L.A. Gaston, J.D. Richardson, R.L. Ficklin. 2009. Assessment of repeated application of poultry litter on phosphorus and nitrogen dynamics in loblolly pine: implications for water quality. Forest Ecology and Management.
- Ficklin, R. L., S. M. Foley, and R. E. Kissell, Jr. 2007. Evaluating soil chemical properties and nutrient concentrations through the use of chemical and near infrared spectroscopic analytical techniques. Journal of the Arkansas Academy of Science 61:44-50.
- Ficklin, R.L. and M.G. Shelton. 2007. Effects of light regime and season of clipping on the growth of cherrybark oak, white oak, persimmon, and sweetgum sprouts. Journal of the Arkansas Academy of Science 61:51-58.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: Near infrared reflectance spectroscopy (NIRS) and multivariate modeling were utilized to quantify relationships between Ozark forest understory vegetation and the soils in which the vegetation grew. NIRS calibration models were developed from spectral scans of both soil and Vaccinium spp. foliage to evaluate the feasibility of applying NIRS analytical techniques for rapid assessment of changes in soil carbon in managed forest ecosystems. Two regional and two national presentations were given on this work. One manuscript on the soil spectral models is in press, and a second manuscript relating soil and vegetation using spectral models currently is in review. One Master's thesis was defended and delivered on this work. The biomass project initiated during 2006 was instrumented to facilitate monitoring of volumetric water content and fine-root turnover in the rooting zone of the selected tree species established for the study. The data collected on soil moisture and root growth
during 2007 were used to calibrate sampling methodologies for measuring changes in soil chemistry that influence carbon sequestration in the soils of the study area as well as the aboveground biomass that is to be used as a bioenergy feedstock. Signage also was installed in this study area to improve the use of the area as a demonstration and field tour site. Forest and pasture areas in SE Arkansas that were treated with poultry litter and commercial fertilizers for monitoring changes in soil and water chemistry were used extensively for educational activities in 2007. A field day for practicing foresters and other land managers was conducted at the experiment station on which the study is established, and forestry students also toured the study area as part of a summer field studies course.
PARTICIPANTS: Shane M. Foley, Graduate Research Assistant Robert E. Kissell, Jr., Assistant Professor of Wildlife Management and Spatial Information Systems (Co-Principal Investigator) Hal O. Liechty, Professor of Forest Ecology (Co-Principal Investigator) Michael G. Shelton, Research Forester, USDA Forest Service-SRS (Co-Principal Investigator) University of Arkansas at Monticello Arkansas Game and Fish Commission U.S.D.A. Forest Service
PROJECT MODIFICATIONS: There was a significant level of seedling mortality in the biomass study one year after establishment. Seedlings that were planted in buffer areas (non-monitoring areas) were transplanted during the dormant season to replace dead seedlings. The transplanted seedlings are from the same initial planting stock, and transplantation during the dormant season is expected to reduce or eliminate long-term effects of the transplantation on growth measurements.
Impacts
NIR Spectral data were significantly correlated with crude protein, acid detergent fiber and neutral detergent fiber in Vaccinium spp. vegetation in addition to a number of other elements in the foliage. NIRS models of soil samples from the Ozark Highlands also indicated significant correlations for several chemical properties, and the success of these preliminary modeling efforts has spawned a new research project. I initiated the new NIRS project for modeling soil carbon and other chemical and physical soil properties in forested areas of the Lower Mississippi Alluvial Valley (LMAV) of Arkansas. In this new research effort, models are being developed for a soil series commonly found in the LMAV as well as the Western Gulf Coastal Plain region of Arkansas. A graduate research assistant was recruited and is working on this new initiative. By developing spectral equations for soils based on established soil map units, it should be possible for researchers and resource
managers to utilize NIRS technology for expediting biogeochemical characterizations of plant and soil samples. Implementation of this technology will improve sustainable forest resource management. The "synthetic mineral soil" (SMS) compound I developed has been adopted in multiple laboratories as the quality control standard when analyzing carbon and nitrogen in soils via dry combustion. It is my intent to evaluate the use of the SMS in the development of NIRS spectral models in combination with the new applications of NIRS I am researching.
Publications
- Ficklin, R.L., S.M. Foley and R.E. Kissell, Jr. 2007. Quantifying soil chemical properties using near infrared spectroscopy. Journal of the Arkansas Academy of Science (in press).
- Ficklin, R.L. and M.G. Shelton. 2007. Effects of light regime and season of clipping on the growth of cherrybark oak, white oak, persimmon, and sweetgum sprouts. Journal of the Arkansas Academy of Science (in press).
- Ficklin, R.L and S.M. Foley. 2007. Chemical Analysis of Ozark Forest Soils Through Near Infrared Reflectance Spectroscopy. Abstract- International ASA-CSSA-SSSA meetings. New Orleans, LA. November 4-8, 2007.
- Ficklin, R.L and S.M. Foley. 2007. Using Near Infrared Reflectance Spectroscopy to Relate Forest Soil and Plant Chemistry. Abstract- International ASA-CSSA-SSSA meetings. New Orleans, LA. November 4-8, 2007.
- Foley, Shane M. 2007. Utilizing near infrared reflectance spectroscopy as a tool for assessing soil/plant chemistry and forage quality in the Ozark Highlands. Masters Thesis. University of Arkansas, Monticello. 117 pp.
- Foley, S.M., R.L. Ficklin and R.E. Kissell, Jr. 2007. Utilizing near infrared reflectance spectroscopy as a tool for relating plant and soil chemistry. Forest Ecology and Management (pending).
- Foley, S.M., R.E. Kissell, Jr. and R.L. Ficklin. 2007. Utilizing near infrared spectroscopy to determine forage quality of blueberry plants in the Ozark Highlands for white-tailed deer. Journal of Wildlife Management (pending).
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Progress 01/01/06 to 12/31/06
Outputs
The field sampling for the Ozark investigation of soil and plant biogeochemical interrelationships and herbaceous plant forage quality is complete, and additional near infrared (NIR) spectral analyses were performed on soil samples as well as the plant tissue samples. I determined that Vaccinium spp. foliage was significantly correlated with soil C, N, Ca, pH, and P, and spectral data explained more than fifty percent of the variation in soil nutrient content. Furthermore, spectral data were significantly correlated with CP, ADF, and NDF, with ninety to ninety-nine percent of the variation in forage properties explained by the spectral data. By increasing the size of the spectral database is should be possible for researchers and resource managers to utilize NIRS technology for expediting biogeochemical characterizations of plant and soil samples. Implementation of this technology will improve sustainable forest resource management. I, along with a multidisciplinary
research team, have initiated a biomass project in SE Arkansas, and provisions are in place to expand the Ozark spectral research into the Lower Mississippi Alluvial Valley (LMAV). Plots have been laid out for the establishment of five woody species and one grass species to quantify biomass production and quality. This research is important for expanding biofuel technology in the cellulose-rich state of Arkansas. The study of changes in soil chemistry and water quality in pastures and forests following poultry litter applications continues, and year three soil samples were extracted in January of this year. Results to date suggest that forest stands are desirable locations for litter disposal, as nitrogen mineralization and subsequent nitrification were slower in forest plots. Accordingly, nitrates in soil water were lower in the forest stand which suggests that for a given quantity of litter applied, less nitrogen is likely to enter the groundwater in the forest compared to the
pastures. Monitoring of soil, soil water, and runoff water will proceed until the system reaches nitrogen and/or phosphorus saturation. To address the objectives outlined in my CRIS project it is critical that I be able to accurately determine carbon and nitrogen contents in soils, and this need is common to researchers around the globe. Standardized soil samples are very limited in supply and are very expensive, so a substitute has been sought by many researchers for several years. This year I published my findings on a compound that behaves as a mineral soil sample behaves in dry combustion analyzers. The main advantages of this compound include low cost and the ability to customize the concentration of carbon and nitrogen in samples that are being used for machine calibration or quality control check samples.
Impacts
The Ozark work has proven that the use of NIRS for assessing biogeochemical parameters related to site productivity is effective and accurate, which should make site characterization work in the future more cost effective. The biomass and the poultry litter studies both address timely agricultural/silvicultural issues related to renewable energy and preservation of environmental quality and ecosystem services. The compound that I developed for dry combustion analyzers has garnered attention from researchers and laboratory managers across the country and around the globe.
Publications
- Ficklin, R.L., R.I. Dresbach and J.D. Richardson. 2006. A reliable, inexpensive method for creating samples of known carbon and nitrogen concentrations for use in dry combustion C-N analyzers. American Laboratory News 38(17): 26-27.
- Ficklin, R.L., S.R. Mehmood and P.F. Doruska. 2006. Integrating science into public policy: challenges and opportunities for improved forest carbon accounting. Journal of Agricultural, Food and Environmental Sciences (ISSN 1934-7235). Available at http://www.scientificjournals.org/articles/1026.htm (verified 20 Feb. 2007).
- Richardson, Joshua D. 2006. Effects of poultry litter applied to pine plantations and pastures on water quality and soil nitrogen mineralization. Masters Thesis. University of Arkansas, Monticello. pp. 105.
- Ficklin, R.L. 2006. Factors for forest landowners to consider when marketing the value of carbon sequestration by their loblolly pine stands. Abstract- Arkansas Forest Resources Center Symposium. Ferndale, Arkansas. May 25, 2006.
- Foley, S.M., R.L. Ficklin and R.E. Kissell, Jr. 2006. Relationships among soils, forage plant quality, and White-tailed deer reproduction in the Ozark highlands. Abstract- Arkansas Forest Resources Center Symposium. Ferndale, Arkansas. May 25, 2006.
- Richardson, J.D., H.O. Liechty, R.L. Ficklin, S.D. Wilson. 2006. Using poultry litter as a nutrient amendment in mid-rotation loblolly pine plantations: Short-term impacts on groundwater qualityin comparison to pasture application areas. Abstract- Arkansas Forest Resources Center Symposium. Ferndale, Arkansas. May 25, 2006.
- Foley, S., Kissell, R.E., and Ficklin, R.L. 2006. Relationships Between Soil and Forage Plant Quality Related to White-Tailed Deer in the Ozark Highlands. Abstract-The Wildlife Society Conference. Anchorage, AK. September 25-29, 2006.
- Kissell, R.E., Hines, R., Foley, S., and Ficklin, R.L. 2006. Changes in Deer Weights Over Time on the White River National Refuge. Abstract- The Wildlife Society Conference. Anchorage, AK. September 25-29, 2006.
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Progress 01/01/05 to 12/31/05
Outputs
Destructive sampling of loblolly pine seedlings and processing and analyzing soil samples for the rhizodeposition project is complete with a subset of biomass samples awaiting processing. Soil texture was found to correlate well with observed changes in soil carbon. Once other soil and plant biomass chemical parameters are analyzed, developing a model for estimating soil carbon enrichment is planned. The poultry litter study of the effects of litter applications on soil and water chemistry has yielded preliminary results that suggest more nitrate ends up in soil and surface waters in pastures than in forests. Estimates of nitrogen mineralization potentials were conducted following aerobic incubations, and the results of these procedures suggest that litter applications may differentially alter the microbiota in pasture and forest soils, resulting in changes in rates of mineralization and nitrification. Changes in mineralization potentials appear to be linked with the
trends observed in both soil and runoff waters. The Ozark study of the relationships between soil fertility, forage quality, and foliar spectral signatures has been fully established, and soil samples from the fall sampling period have been analyzed. Some spectral analyses have been conducted on foliar tissues, but further spectral analyses will not occur until weather conditions are appropriate. A new project was implemented to investigate what influence forest vegetation has on the accuracy and precision of commercial grade GPS units that often are used for non-GIS research, including the studies that I am conducting.
Impacts
With increasing interest in sequestering atmospheric carbon, Arkansas landowners will have a tool for estimating soil carbon sequestration potential based on the relationships defined between loblolly pine biomass and foliar chemistry with soil carbon enrichment. A tool/model such as this is needed if landowners are to maximize their benefit in a carbon credit trading system. Early results indicate that forests are as good as or better than pastures for the disposal of poultry litter. These findings suggest that poultry farmers will have more options for the efficient and environmentally responsible disposal of litter. Data from the Ozark study will improve the understanding of the relationship of deer health as it is related to the nutritional value of available forage.
Publications
- Ficklin, R.L., J.D. Richardson and H.O. Liechty. 2005. Carbon and nitrogen status of forest and pasture soils nine months after poultry litter application. Abstract No. 324-5. International ASA-CSSA-SSSA meetings. Salt Lake City, Utah. November 6-10, 2005.
- Ficklin, R.L. 2005. Soil carbon enrichment by loblolly pine rhizodeposition. Abstract. Southern Regional Branch ASA meetings. San Antonio, Texas. June 19-21, 2005.
- Ficklin, R.L. 2005. Loblolly pine biomass corollaries of soil organic carbon content. In: Arkansas Academy of Science- 89th Annual Meeting. Conway, Arkansas. April 8-9, 2005. pp. 36.
- Ficklin, R.L., M.G. Shelton and A.M. Carter. 2005. Carbon sequestration with loblolly pine-storage both aboveground and belowground. In: Proceedings of the 2004 Arkansas Forestry Symposium. R.E. Parris, Ed., Little Rock, AR, May 26, 2004. pp. 71.
- Ficklin, R.L. 2005. Skidding logs with draft animals: still a viable option? Faculty Impact Statements; Romund, Holland & Medders, Eds. Arkansas Agricultural Experiment Station, Research Series 528. pp. 78.
- Liechty, H.O., J. Richardson, R. Colvin, S. Wilson, and R.L Ficklin. 2005. Surface and soil water chemistry following poultry litter application to pastures and a loblolly pine plantation. Abstract No. 299-10. International ASA-CSSA-SSSA meetings. Salt Lake City, Utah. November 6-10, 2005.
- Richardson, J.D., R.L. Ficklin and H.O. Liechty. 2005. Effects of land-use and poultry litter application on water quality and soil nitrogen mineralization. Abstract No. 34-1. International ASA-CSSA-SSSA meetings. Salt Lake City, Utah. November 6-10, 2005.
- Richardson, J.D., H.O. Liechty and R.L. Ficklin. 2005. Effects of land-use and poultry litter application on soil nitrogen mineralization. Abstract. Southern Regional Branch ASA meetings. San Antonio, Texas. June 19-21, 2005.
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Progress 01/01/04 to 12/30/04
Outputs
The controlled greenhouse evaluation of loblolly pine seedling rhizodeposition to soil carbon enrichment has run its cycle, and final destructive sampling of remaining samples is underway. Final analyses are forthcoming, but trends with respect to aboveground biomass relative to belowground biomass appear highly correlated with soil texture and fertilization treatments. Correlations between aboveground woody biomass and soil carbon enrichment via rhizodeposition will be determined upon completion of sample processing and chemical analyses. Plans and preparations for a field study were suspended after on-site soil sampling revealed that proposed field sites were too heterogeneous to expect meaningful interpretations of soil/seedling relationships to rhizodeposition. Alternatively, the correlation of micronutrients with observed carbon and nitrogen changes are being determined. In addition to the ongoing work on carbon-nitrogen dynamics following poultry litter
applications to forest and pasture soils, a new study has been initiated to evaluate the relationship of soil/site chemistry with forage quality for deer health. This project will establish foundational information on Arkansas Ozark soils, forage/browse, and white-tailed deer populations. Soil samples one year after the first poultry litter application to forest and pasture have been taken, and sample processing and C-N analyses are in progress. Other elemental analyses are scheduled after samples are prepared.
Impacts
These ongoing projects are designed to be specifically relevant to Arkansas stakeholders; however, each project also has scientific merit and applicability to other states and nations. Quantifying and modeling soil carbon sequestration through rhizodeposition has financial and ecological implications, as does the study of forest soil and pasture soil responses to poultry litter amendments. The proposed research to study soil/forage quality and deer health is an integrated project that is expected to provide a more complete understanding of deer herd health in the context of forage quality and soil properties.
Publications
- Ficklin, Robert L.; Dwyer, John P. and R.D. Hammer. 2004. Changes in soil organic carbon concentration and quantity following selection harvesting. Proceedings of the 14th Central Hardwood Forest Conference. USDA Forest Service General Technical Report NE-316; pp. 217-223.
- Ficklin, R.L., M.G. Shelton and A.M. Carter. 2004. Carbon sequestration with loblolly pine- storage both aboveground and belowground. Poster paper, proceedings pending. Arkansas Forest Resources Center Symposium. May 26th. Little Rock, AR.
- Ficklin, R.L., B. Zeide and R. Colvin. 2004. Fertilization of agroforests- a double-edged sword? In: Book of Abstracts. The 1st World Congress of Agroforestry. Chair: P. K. R. Nair. Gainesville, Florida, USA. June 27 to July 2, 2004. pp. 304.
- Ficklin, R.L., M.G. Shelton. 2004. Effects of fertilization on root-to-shoot biomass allocations in loblolly pine seedlings. Faculty Impact Statements; Medders, Romund & Holland, Eds. Arkansas Agricultural Experiment Station, Research Series 516. pp. 26.
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Progress 01/01/03 to 12/31/03
Outputs
In addition to publishing data from pre-existing research, presentations and publications were submitted on the linkage of carbon policy and forest management. A greenhouse project has been initiated to quantify soil carbon enrichment via rhizodeposition from loblolly pine seedlings, and destructive sampling of seedlings from the first growing season has occurred. Carbon, nitrogen, and other elemental analyses are being performed on both the soil and the plant tissues of the greenhouse grown seedlings at present. Trends already have been observed for plant photosynthate allocation in roots and foliage as a function of fertilization and growing medium (sand or loam soil). Water stress was eliminated as a factor by watering on a mass basis, and soil water contents are kept below saturation and above wilting point. Study sites have been identified for the establishment of a field trial for the measurement of soil carbon enrichment by loblolly pine under actual plantation
conditions. The loblolly pine seedlings for the field planting have been purchased from an International Paper nursery in Arkansas, and these seedlings are from the same family of second generation improved stock. Using the same family of seedlings will minimize genetically controlled variations in rhizodeposition; however, there still will be some variation as these seedlings are not clones. The variability of soil properties in the study areas is expected to be the primary source of rhizodeposition variability. To minimize this field variability effect, the study areas were selected using published soil survey information. All seedlings will be planted in areas classified as the same soil map unit. Another project has been initiated to quantify changes in soil carbon and nitrogen following poultry litter applications to both forest and pasture lands in southwest Arkansas. Baseline soil samples have been extracted, and sample preparation is underway.
Impacts
The quantification of soil carbon enrichment via loblolly pine rhizodeposition will provide data suitable for modeling potential soil carbon sequestration in loblolly pine plantations. Given the importance of intensive silviculture in Arkansas and the potential valuation of carbon sequestration, these studies provide a critical component for comparing the effects of different forest management practices on the sequestration of atmospheric carbon. By establishing a field study in areas consisting of the same type of soil map unit, it is hoped that soil characteristics identified in the soil survey can be used as proxies for estimating soil carbon enrichment by loblolly pine. The implications of the poultry litter project are profound for Arkansas. Disposal of litter is becoming a serious problem, as many pastures that have been used for litter disposal are becoming saturated with phosphorus. If forest soils are suitable for litter disposal, then these poultry waste
materials may be an asset for improving forest site productivity. Concurrently, as site productivity improves, it is expected that carbon sequestration also will increase in both the soil and the trees.
Publications
- Ficklin, Robert L.; Dwyer, John P. and R.D. Hammer. 2003. In Press. Changes in soil organic carbon concentration and quantity following selection harvesting. Proceedings of the 14th Central Hardwood Forest Conference. 10 p.
- Ficklin, R.L., R.D. 2003. Measuring soil organic carbon in forest landscapes with diverse landforms. Faculty Impact Statements; Medders & Romund, Eds. Arkansas Agricultural Experiment Station, Research Series 503. pp 48-49.
- Ficklin, Robert L.; Mehmood, S.R. and P.F. Doruska. 2003. In Review. Integrating science into public policy: challenges and opportunities for improved forest carbon accounting. In: For. Ecol. and Mgmt. - special publication of the 10th North American Forest Soils Conference-Forest soils research theory, reality and its role in technology transfer. July 20-24. Sault Ste. Marie. 40 p.
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