Wilson, Sally

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Digital Kenyon: Research, Scholarship, and Creative ExchangeKenyon Summer Science Scholars Program Summer Student Research ScholarshipSummer 2011Quantifying soil carbon sequestration rates, acritical ecosystem service, from measures ofwetland condition in freshwater wetlands of OhioSally WilsonFollow this and additional works at: https://digital.kenyon.edu/summerscienceprogramPart of the Biology CommonsThis Poster is brought to you for free and open access by the Summer Student Research Scholarship at Digital Kenyon: Research, Scholarship, andCreative Exchange. It has been accepted for inclusion in Kenyon Summer Science Scholars Program by an authorized administrator of Digital Kenyon:Research, Scholarship, and Creative Exchange. For more information, please contact noltj@kenyon.edu.Recommended CitationWilson, Sally, "Quantifying soil carbon sequestration rates, a critical ecosystem service, from measures of wetland condition infreshwater wetlands of Ohio" (2011). Kenyon Summer Science Scholars Program. Paper 151.https://digital.kenyon.edu/summerscienceprogram/151Quantifying soil carbon sequestration rates, a critical ecosystem service, from measures of wetland condition in freshwater wetlands of Ohio Sally Wilson1 and Siobhan Fennessy2 1. Undergraduate at Kenyon College 2. Professor of Biology, Kenyon College Introduction Results Discussion 0 10 20 30 40 50 60 70 0 0.5 1 1.5 2 Depth (cm) Bulk density (g/cc) Figure 3. Bulk density analysis of 2cm increments from a 58cm soil core taken from Ballfield, a high-condition depressional site, in Knox County, Ohio. Sampled in June, 2010. 0 5 10 15 20 25 30 35 0 0.5 1 1.5 2 Depth (cm) Bulk density (g/cc) Figure 4. Bulk density analysis of 2cm increments from a 32cm soil core taken from Hellbender, a moderate-condition riverine site, in Knox County, Ohio. Sampled in June, 2010. 0 5 10 15 20 25 30 35 40 45 50 0 0.5 1 1.5 2 Depth (cm) Bulk density (g/cc) Figure 5. Bulk density analysis of 2cm increments from a 44.5cm soil core taken from Kokosing, a moderate-condition riverine site, in Knox County, Ohio. Sampled in June, 2010. 0 5 10 15 20 25 0 0.5 1 1.5 2 Depth (cm) Figure 6. Bulk density analysis of 2cm increments from a 23cm soil core taken from Batnest, a low condition depressional site, in Knox County, Ohio. Sampled in June, 2011.  Bulk density (g/cc) Figure 9. A conceptual model of ecosystem service production. Figure 2. A. S. Moseley and S. Wilson in the field with soil corers. B. Extruded soil core. A. B. Methods Site name County (OH) HGM type Relative ecological condition Ballfield Knox Depressional High Batnest Knox Depressional Low Hellbender Knox Riverine Moderate Kokosing Knox Riverine Moderate Bee rescue Knox Depressional High Blackout Cuyahoga Depressional Low Lizard tail Cuyahoga Riverine Moderate-high  Secret marsh Cuyahoga Depressional High Skunk forest Cuyahoga Riverine High Vernal pool Cuyahoga Riverine Moderate-low Table 1. Experimental wetland sites (n=10) selected along a gradient of disturbance. High condition sites=least disturbed. Low condition sites = most disturbed.  Figure 7. Representative 137Cs profiles with depth for A. Ballfield B. Hellbender and C. Kokosing experimental sites. Zeroes denote where 137Cs was no longer detected. Cesium-axis values differ between graphs.   Soil Sampling and Analysis Soil cores 8.5 cm diameter by up to 60 cm deep were sectioned in the field into 2cm increments (Figure 3). Increments were air dried at 70°C and weighed for bulk density Bulk density = dry weight       volume of solids and pore spaces Bulk density provides a measure of soil porosity. Porosity determines root penetration, water movement, and gas movement. Ground and sieved samples were analyzed for 137Cs to determine vertical accretion. Cesium-137 maxima had well-defined peaks that represent the location of the soil surface in 1964, the year of peak deposition of atmospheric 137Cs from aboveground weapons testing. Accretion rate (mm/yr) = depth (mm) of Cs-137 peak in soil / time (years) since 1964.  Accumulation of C can be estimated from 137Cs vertical accretion rate and carbon concentration. A. B. Site name Ecological condition HGM type Accretion rate  (mm/yr) Lizard tail Moderate-high Riverine 1.5 Skunk forest High Riverine 1.5 Kokosing Moderate Riverine 3.3 Table 2. Comparison of soil accretion rate among riverine sites of varying ecological condition. The soil accretion rate at Kokosing was more than double the rate of accretion at  Lizard tail and Skunk forest, two other riverine sites of higher condition. Acknowledgements  Bulk density Of the local sites, the soil core taken at Batnest had the greatest bulk densities (Figure 6).  Typical mineral soils have bulk densities that range from 1.0 to 1.6 g cm-3. A bulk density greater than 1.6 g cm-3 may indicate compaction, which means the soil has low total porosity. Low porosity tends to inhibit gas movement and storage.  As a result, the rate of carbon accretion may be lower at Batnest due to compaction. Potential source of compaction: agricultural machinery (Figure 8). Future work I would like to acknowledge Dr. Siobhan Fennessy for her constant support and advice throughout this project; Sally Moseley ‘12, my field partner; Dr. Denice Heller Wardrop of Penn State and the Riparia research team, collaborators in this project; and funding from the EPA-STAR, EMAP, and USDA grants and the HHMI grant to Kenyon College’s Summer Science Scholar program. Bridgham, S.D. et al. 2006. The carbon balance of North American wetlands. Wetlands, 26(4): 889-916. Hossler, K. and V. Bouchard. Soil development and establishment of carbon-based properties. Ecological Applications, 20(2): 539-553. Loomis, M.J. and C.B Craft. 2010. Carbon sequestration and nutrient (Nitrogen, Phosphorus) accumulation in river-dominated tidal marshes, Georgia, USA. SSSAJ, 74(3): 1028-1036. Soil accretion Of the local sites, Kokosing had the greatest soil accretion rate (Figure 7).  Compared to other riverine sites, the soil accretion rate at Kokosing is higher (Table 2). Due to hydrologic alterations, Kokosing is beginning to functioning like a depressional wetland site with regard to soil accumulation. Figure 8. Photograph of Batnest, a low-condition depressional wetland in Knox County, Ohio.  Question How is the ability to provide carbon storage (quantified using carbon accretion rates) affected by anthropogenic disturbance?  Hypothesis We expected carbon accretion rates to be greater at depressional vs. riverine sites due to hydrology and greater at high condition vs. low condition sites due to anthropogenic stressors. We predict carbon accretion rates will decrease as the stressor gradient increases (Figure 1).  10 experimental wetland sites were selected along a gradient of disturbance (Table 1).  Disturbances: 1. Land use adjacent to the site and/or 2. Hydrologic alterations through drainage.  Accumulation of carbon (accretion) can be calculated using 137Cs vertical accretion rate and bulk density of soil core samples. Wetlands provide ecosystem services that increase our quality of life, including: the preservation and support of biodiversity, flood abatement, and nutrient transformation and sinks. Wetland soils are a major reservoir of organic matter and an important carbon sink.  Carbon accumulation supports anaerobic pathways of microbial metabolism and contributes to long-term wetland stability through organic matter accumulation and mineral sediment deposit.  Carbon storage capacity varies as a function of wetland type and condition. References 2011 summer research group in the Kokosing River. Nutrient analysis of organic C and N using a CHN analyzer and total P using colorometric analysis. Quantify C, N, and P accumulation using 137Cs vertical accretion rate and bulk density. Model estimated amount of carbon storage provided, taking into account the interactions in Figure 9. This model has application for restoration, management and policy. Figure 1. Hypothetical relationship between ecosystem service provisioning and stressor gradient.  

Quantifying soil carbon sequestration rates, a critical ecosystem service, from measures of wetland condition in freshwater wetlands of Ohio

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Quantifying soil carbon sequestration rates, a critical ecosystem service, from measures of wetland condition in freshwater wetlands of Ohio

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