EXAMINATION OF FOREST SOILS-VEGETATION ASSOCIATIONS AND SITE PRODUCTIVITY BY LANDFORM

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: MCINTIRE-STENNIS
• Reporting Frequency: Annual
• Accession No.: 1001220
• Project Start Date: Dec 10, 2013
• Project End Date: Sep 30, 2018
• Program Code: [(N/A)]- (N/A)

Recipient Organization
UNIVERSITY OF ARKANSAS
(N/A)
FAYETTEVILLE,AR 72703

Performing Department
Forestry And Natural Resources

Non Technical Summary
The characterization of spatial and temporal variation in soil properties and the composition and growth of associated vegetative communities will be accomplished through the collection of soil samples using landform features for sampling stratification. Similarly, the vegetation occupying the landforms will be characterized by type and rate of growth. Statistical analyses of soils and vegetation will be conducted for inferences on the relationship between soil properties and the vegetative communities supported by the soil resource. Through an improved understanding of spatial and temporal patterns of soil properties and their influence on plant communities, management of forest ecosystems for multiple objectives can be improved.

Animal Health Component

70%

Research Effort Categories

Basic

0%

Applied

70%

Developmental

30%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
102	0110	1070	25%
101	0199	2061	45%
123	0699	1070	30%

Knowledge Area
102 - Soil, Plant, Water, Nutrient Relationships; 101 - Appraisal of Soil Resources; 123 - Management and Sustainability of Forest Resources;

Subject Of Investigation
0110 - Soil; 0199 - Soil and land, general; 0699 - Trees, forests, and forest products, general;

Field Of Science
1070 - Ecology; 2061 - Pedology;

Keywords

soil-plant associations

ecosystem services

forest site productivity

Goals / Objectives
This research will address questions relative to sustainable forest productivity and ecosystem services. Soil chemical and physical properties in both natural and plantation forest systems that influence ecosystem productivity will be measured, and attention will be given to correlations of soil properties and vegetative communities within and between landforms.

Project Methods
Methods: The Natural Resource Conservation Service (NRCS) through its National Cooperative Soil Survey (NCSS) program has mapped the soils of the United States in an effort to provide information on sustainable land uses for a broad range of soils. The soil surveys provide data on the general chemical, physical, and hydrological properties of soils, and soil map units (soil series) are delineated on the basis of similarities across soil individuals/ polypedons. Due to limitations in sampling for a given soil series, a soil survey only provides relatively coarse resolution data from which forest management decisions can be made, but the NRCS-NCSS map units provide a widely recognized stratification of soil variability. Accordingly, this research will utilize these established map units as a first consideration in sampling stratification. Within each map unit samples will be extracted from within the landform features that characterize the landscape, and spatial and temporal variation of soil properties will be examined within and among landforms. Soil Analyses Soil samples will be air dried and passed through a 2 mm sieve using a Ro-Tap sieve shaker, removing any roots or organic matter that become visible during the procedure. Sub-samples weighing 0.5 g will be analyzed in duplicate by means of catalytic tube combustion using an Elementar VarioMAX CN Macro Elemental Analyzer (Elementar Analysensysteme GmbH, Hanau, Germany) to determine the percent carbon, percent nitrogen, and the C:N ratio for each sample. Duplicates with variation greater than one standard deviation from the mean will be analyzed a second time. Extractions will be completed by placing 5.0 g of soil in a pre-weighed 60 ml syringe pre-packed with 1.0 g of filter pulp. Samples will be saturated with 10ml of 2M KCl prior to extraction. A SampleTek Model 24VE Programmable Vacuum Extractor (Mavco Industries, Inc., Lincoln NE) will be used to extract the KCl solution from the sample vials at a rate of 0.67 ml min-1. An additional 20 ml of 2M KCl will be added throughout the extraction process to ensure complete disassociation of the mineral nitrogen in the samples. Extracted solutions will be immediately weighed and refrigerated for a maximum duration of three days before chemical analyses are completed. Weights of the extractions will be used to determine the dilution factor of the 2M KCl solution using 1.085 g ml-1 as the density of 2M KCl. Chemical analysis will be performed using a QC 8000 Injection Analyzer (Latchet Instruments, Loveland, CO.). Nitrate and ammonium concentrations will be analyzed using QuikChem Methods 12-107-04-1-B (Lachat Instruments, 1992) and 12-107-06-2-A (Lachat Instruments, 1990), respectively. The samples will then sent to the University of Arkansas-Fayetteville Agricultural Diagnostic Laboratory for additional analysis of pH, P, K, Ca, Mg, S, Na, Fe, Mn, Zn, Cu, and B concentrations. Soil pH will be determined using a 1:2 soil/water ratio. The elemental analyses will be performed using a Mehlich 3 (1:10) extraction followed by inductively coupled plasma (ICP) spectroscopic analysis. Vegetation Sampling and Analyses For each landform vegetation composition will be characterized by species, frequency, and percent cover. Upon return to the laboratory, forest vegetation samples will be immediately placed in a drying oven at 60°C for 24 hours (Davidescu and Davidescu, 1982). Dried material was ground using a Wiley® mill (C.W. Brabender Instruments, Inc., South Hackensack, NJ) until fragments passed through a 1 mm sieve. Samples will then be placed into air-tight plastic containers, labeled, and refrigerated at 5° C. Foliar samples will be analyzed in duplicate sub-samples of 0.15 g for percent carbon, percent nitrogen and C:N ratio by means of catalytic tube combustion using an Elementar VarioMAX CN Macro Elemental Analyzer (Elementar Analysensysteme GmbH, Hanau, Germany). The remaining sample will be sent to the University of Arkansas-Fayetteville Agricultural Diagnostic Laboratory to be analyzed for P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, crude protein, acid detergent fiber (ADF), and neutral detergent fiber (NDF). Ankom digestion will be used to determine ADF and NDF. Elemental concentrations will be analyzed by HNO3/H2O2 digestion with subsequent ICP spectrophotometric analysis. Procedures for Achieving Project Objectives Following the sampling and analytical procedures described above, data will be analyzed in multiple ways to achieve the objectives of this project. Spatial patterns of soil properties across landforms and landscapes (objective one) will be modeled using spatial interpolation techniques, including ordinary kriging. Spatial analyses of soil density and texture are the primary physical characteristics that will be modeled, and analyses of carbon and nitrogen are the primary chemical properties. The spatial analyses of soil density and texture data for one study site in the Lower Mississippi Alluvial Valley (LMAV) have been initiated. Temporal patterns will be discerned by repeated sampling during multiple times/seasons of the year for changes in soil chemistry. Physical properties will not be evaluated temporally, as these properties exhibit little change over short intervals. Correlations between soil properties and vegetative communities (objective two) will be examined using regression analyses to relate soil bulk density, texture, carbon, and nitrogen with vegetation diversity and abundance. Landform features within landscapes will be utilized as a basis for sampling stratification, since patterns of vegetation species are known to differ across landforms. Additionally, analyses will be performed to relate the nutrient status of the vegetation with the nutrient status and physical properties of the soil in which it is growing. Growth of vegetation as a function of soil properties (objective three) will be evaluated based upon tree diameter and height growth across landforms in the same landscape but with variable density, texture and C:N conditions. If funding is secured to expand on these measurements, a broader evaluation of biomass accumulation that encompasses all vegetation on a site will be performed.

Progress 12/10/13 to 09/30/18

Outputs
Target Audience:University researchers, university students, and land management decision makers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Results have been disseminated through journal publications and presentations at professional meetings. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? One component of this research was focused on a tract of land designated as the Bob White Memorial Wetlands Research and Teaching Station (BWMW). This component addressed spatial variation of soil properties and differences in soil C and N across microtopographic features. A graduate student was hired to address questions related to differences in vegetation diversity across engineered microtopographic features, in addition to quantifying differences in soil C, N, and bulk density. A second component for evaluating ecosystem function in a natural forested wetland and in a restored forested wetland- the BWMW. This project built upon the soil and vegetation work conducted in the previous BWMW component. A second graduate student was hired to examine rates of leaf litter decomposition which were used as a metric of ecosystem function, since rates of nutrient turnover are related to nutrient availability for plant growth and overall site productivity and ecosystem energetics. In addition to comparing decomposition rates, the diversity of herbaceous vegetation also was compared between the natural and restored areas. For the decomposition aspect of the research, the leaf litter consisted of two species: green ash (Fraxinus pennsylvanica) and willow oak (Quercus phellos), and the decomposition study was replicated on three topographic features: ridges, swales and flats. Soil and litter samples were analyzed for C and N, as the ratio of these elements strongly influences decomposition rates. Engineered microtopographic features did provide a diversity of microsites for hydrophyte (wetland plant) establishment. Species richness, total plant cover and diversity were significantly influenced by microtopographic feature, similar to natural wetland conditions. These findings suggest that restoration efforts are being effective for creating conditions suitable for forest wetland vegetation. No significant trends in soil properties were found across the microtopographic features after twelve years. Decomposition did not differ between study sites with a (p = 0.08) indicating that restoration efforts at the BWMW were effective in restoring function, at least as it pertains to leaf decomposition. Decomposition rates differed over time based on species and collection period. Green ash had a significantly faster decomposition rate and higher litter quality than willow oak (P < 0.01). Indices were used for determining composition similarities between the BWMW and a comparison forested wetland. The BWMW had a species richness of 33 and the comparison site had a species richness was 47. Beta diversity between the two sites was 76 species, this value is high and suggests there is low similarity between the two sites. Sorensen-Dice Similarity Index value was calculated as 0.05, where on a scale of 0-1 a low value indicates low similarity in composition. The low similarity between the two sites suggests that vegetation composition at the BWMW has not been fully restored to conditions comparable to a natural setting. The decomposition rates were not significantly different and this could be because the soil C:N ratio was not significantly different between the two sites either. Soil C:N ratio has been found to influence decomposition rates. An explanation for this is the presence of Baccharis halimifolia (Eastern baccharis). Baccharis halimifolia inhibits other species from colonizing. The results from this study provide mixed evidence that restoration at the BWMW is succeeding; decomposition rates suggest success in restoring nutrient cycling, while vegetation lacks similarity.

Publications

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:University researchers, university students and land management decision makers Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Results have been disseminated through journal publications and presentations at professional meetings. What do you plan to do during the next reporting period to accomplish the goals?I will be continuing my work on changes in soil chemical and physical properties in forested wetlands, and I will be evaluating the influence of prescribed burning on soil carbon and nitrogen in upper mineral soil horizons. I will be pursuing additional funding to meet the objectives of my project goals.

Impacts
What was accomplished under these goals? In support of my forested wetland restoration project, I received a grant from the Mondi Group, Inc., in 2016 to examine relationships between soil chemistry and vegetation diversity in combination with the work being conducted on the natural and restored wetland areas. This work still is ongoing. The study area was converted from agricultural production to a wetland restoration area twelve years prior to study establishment. To evaluate the influence of created microtopography on the establishment of both hydrophytic wetland vegetation and hydric soil conditions, soil and vegetation samples were taken at hummock and swale locations, as well as in flat areas that were not disturbed during soil surface manipulation.Differences in total vegetative cover and species diversity were noted across the microtopographic features, but overall species richness did not differ. Greater proportions of hydrophytic wetland species were noted in swales and flats, suggesting that appropriate wetland hydroperiods were present in these locations compared with hummocks. Significant differences in soil density, carbon and nitrogen between swales and hummocks were observed, and these soil data serve as a baseline for future monitoring of hydric soil property development. The findings of this study support the establishment of microtopographic features in previously levelled lands for the reestablishment of wetland vegetation communities and for the restoration of associated forested wetland functions.

Publications

• Type: Journal Articles Status: Published Year Published: 2017 Citation: Sheldon, C.J., R.L. Ficklin, K.P. Fawley, M.W. Fawley, M. Bataineh, A.S. Nelson and S. Wilson. 2016. Vegetation diversity in natural and restored forested wetland sites in southeast Arkansas. Journal of the Arkansas Academy of Science 70:221-231. (published in 2017)
• Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Portner, B, M. Bataineh, M. Pelkki and R. Ficklin. 2017. Comparing the use of pyrometers and thermocouples for estimating prescribed burning flame temperature. 7th International Fire Ecology and Management Congress. November 28-December 2. Orlando, FL.

Progress 10/01/15 to 09/30/16

Outputs
Target Audience:University researchers, university students, and land management decision makers. Specific professional groups include foresters, soil scientists, wildlife biologists and managers, and biologists. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project has provided the opportunity for graduate student training in field sampling, laboratory analyses, data processing, and publishing. Similar professional development opportunities were provided to a research program technician. Landowners also had the opportunity for professional development through their participation in meetings where this research was presented and discussed. How have the results been disseminated to communities of interest?Results have been disseminated through journal publications and presentations at professional meetings. What do you plan to do during the next reporting period to accomplish the goals?As an extension of the work releated to forested wetland restoration, I am examining relationships between soil chemistry and vegetation diversity in combination with the work being conducted on the natural and restored wetland areas. I anticipate that this work will be completed in 2017.

Impacts
What was accomplished under these goals? Issue: In the lower Mississippi alluvial valley (LMAV) in southeast Arkansas, thousands of acres of forested wetlands were converted to agricultural land during the 20th century. Many of these areas proved to be poorly suited for agricultural production, and there are efforts to restore these marginal agricultural lands to forested wetland conditions. To facilitate these conversions, mechanical engineering of microsite topography has been employed as a means of recreating hydrologic regimes similar to those of natural forested wetlands. However, the effectiveness of these efforts has not been evaluated extensively. Activity: A study was conducted to examine whether engineered microtopographic features facilitated the reestablishment of wetland soil conditions and plant communities in an area undergoing restoration in the LMAV. Soil properties measured included bulk density, soil organic carbon, total nitrogen, and C:N. Vegetation parameters measured included total plant cover, plant species richness, plant diversity, and wetland indicator status. Soil and plant measurements were taken in three engineered microtopographic features: swales (depressions), hummocks (mounds) and flats. These features were established twelve years prior to measurements, so this study examined the degree to which vegetation and soil properties have progressed toward natural wetland conditions. Impact: Engineered microtopographic features did provide a diversity of microsites for hydrophyte (wetland plant) establishment. Species richness, total plant cover and diversity were significantly influenced by microtopographic feature, similar to natural wetland conditions. These findings suggest that restoration efforts are being effective for creating conditions suitable for forest wetland vegetation. No significant trends in soil properties were found across the microtopographic features after twelve years.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Sheldon, C.J., R.L. Ficklin, K.P. Fawley, M.W. Fawley, M. Bataineh, A.S. Nelson and S. Wilson. 2016. Vegetation diversity in natural and restored forested wetland sites in southeast Arkansas. April 1-2, 2016.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Sleeper, B.E. and R.L. Ficklin. 2016. Edaphic and Vegetative Responses to Forested Wetland Restoration with Created Microtopography in Arkansas. Ecological Restoration Journal 34(2):117-123.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Sharma, S., J.P. Adams, J.L. Schuler, R.L. Ficklin and D.C. Bragg. 2016. Effect of seedling stock on the early stand development and physiology of improved loblolly pine (Pinus taeda, L.) seedlings. iForest - Biogeosciences and Forestry 9:690-695.
• Type: Journal Articles Status: Accepted Year Published: 2017 Citation: Sheldon, C.J., R.L. Ficklin, K.P. Fawley, M.W. Fawley, M. Bataineh, A.S. Nelson and S. Wilson. In Press. Vegetation diversity in natural and restored forested wetland sites in southeast Arkansas. Journal of the Arkansas Academy of Science.

Progress 10/01/14 to 09/30/15

Outputs
Target Audience:University researchers and university students Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?It is too early to report to the communities of interest. What do you plan to do during the next reporting period to accomplish the goals?During 2016 a full characterization of understory plant diversity across topographic features on both the natural and the restored forested wetland will be completed. Final results of the decomposition component of the investigation also will be completed.

Impacts
What was accomplished under these goals? Field sampling of soils and vegetation was completed for a study initiated in 2014 on natural and restored forested wetland sites. In addition to soil and plant sampling, a leaf litter decomposition study was performed to assess differences in litter turnover rates between the natural and restored wetland areas. The litter consisted of two species (Fraxinus pennsylvanica and Quercus phellos), and the decomposition study was replicated on three topographic features: ridges, swales and flats. Soil and litter samples are being analyzed for C and N, and data preprocessing for statistical analyses has been initiated.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Sheldon, C, R. Ficklin and S. Wilson. 2015. Leaf litter turnover on natural and restored forested wetland sites in Southeast Arkansas. Abstract. Arkansas Academy of Science. Arkadelphia, Arkansas. April 10-11, 2015.
• Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Sleeper, B.E. and R.L. Ficklin. Accepted, under revision. Edaphic and Vegetative Responses to Forested Wetland Restoration with Created Microtopography in Arkansas. Ecological Restoration Journal.
• Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Sharma, S., J.P. Adams, J.L. Schuler, R.L. Ficklin and D.C. Bragg. Accepted, under revision. Effect of seedling stock on the early stand development and physiology of improved loblolly pine (Pinus taeda, L.) seedlings. iForest - Biogeosciences and Forestry.

Progress 12/10/13 to 09/30/14

Outputs
Target Audience: The primary target audience for this project during this reporting period consists of natural resource managers and researchers who are interested in wetland and bottomland hardwood forest (BLHF) lands. A peer-reviewed publication was produced during this reporting period to communicate with this audience. As the project progresses, there will be a second target audience which will include current BLHF landowners and other landowners with tracts of land suitable for establishment of BLHFs. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? From this work four presentations were made: two in Arkansas (Arkansas Department of Environmental Quality; Arkansas Academy of Science), one regional (Southeastern Natural Resources Graduate Student Symposium- Mississippi State University), and one international (Soil Science Society). One peer-reviewed manuscript has been published from this work, and a second manuscript is under preparation. What do you plan to do during the next reporting period to accomplish the goals? As a part of the assessment of ecological function, a leaf litter decomposition study will be installed on the area undergoing wetland restoration (the BWMW) and on a natural forested wetland area. Additionally, plant diversity will be measured across both areas.

Impacts
What was accomplished under these goals? One component of this research is focused on a tract of land designated as the Bob White Memorial Wetlands Research and Teaching Station (BWMW). This component addresses spatial variation of soil properties and differences in soil C and N across microtopographic features, and this aspect of the project is nearing completion. The graduate student I hired to work on the project, Ben Sleeper, is graduating in December. To meet the objectives of this NIFA project, I initiated a new component for evaluating ecosystem function in a natural forested wetland and in a restored forested wetland- the BWMW. This project builds upon the soil and vegetation work conducted in the previous BWMW component. Rates of leaf litter decomposition are being used as a metric of ecosystem function, since rates of nutrient turnover are related to nutrient availability for plant growth and overall site productivity and ecosystem energetics. In addition to comparing decomposition rates, the diversity of herbaceous vegetation also is being compared between the natural and restored areas.

Publications

• Type: Journal Articles Status: Published Year Published: 2014 Citation: Sleeper, B.E. and R.L. Ficklin. 2013. Distribution of soil density at a bottomland hardwood forest wetland restoration, Chicot county, Arkansas. Journal of the Arkansas Academy of Science 67:135-138.