Progress 10/01/07 to 09/30/13
Outputs
Target Audience: Soil Scientist, Cooperative Extension County Agents and Specialist, Farmers, Organic and Limited Resource Farmers Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Graduate student and undergraduate students were trained under this program and opportunities for both faculty student and staff to participate and present at local regional and national meetings. How have the results been disseminated to communities of interest? Information from the project was presented to the scientific and extension communities at local, regional and national meeting. Information was also shared with local farmers through the cooperative extension system. Results were also shared with farmers at the Annual Farmers and the Professional Agricultural Workers Conferences. Classroom presentation was made to students at both the graduate and undergraduate level. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The use of organic mammedmendt is becoming popular as an alternate form of nutirnt for plants. The increase in organic agricultural products and demand for organic food products have called for theeavluationi of other plant nutrient sources and study its impact on soil quality. A field experiment was conducted to evaluate the impact of organic amendments and fertilizer on the soil microbial community in the rhizosphere’s of four sweetpotato cultivars (J6/66, NCC-58, BH, and TU). Experiments were conducted as a randomized complete block design in a 4x4 factorial arrangement with three four replications. Organic amendments were broiler litter (BL), fish fertilizer (FSH), and commercial fertilizer (NPK), and an untreated check were split and applied at the rate of 54.7305 kilogram/acre ( kg/ac) based on soil tests one week after planting and at four weeks as single bands 15cm from the plant and covered. Rhizosphere soil samples were collected at harvest and analyzed using 454 pyrosequencing. Fertilizer had a significant impact on bacteria at every taxonomic level. Significant main effect was found between the sweetpotato cultivar and organic amendments where the soil pH in treatments and sweetpotato variety with BH variety untreated soils had significantly higher pH than other treatments, and the fish fertilizer had significantly lower pH in the TU variety. Fertilizer had no significant impact on soil organic carbon (SOC) but cultivars did with soils from Whatley/Lortan rhizosphere having lower SOC than other cultivars. Plots that received fertilizer and organic amendments had significantly higher enzyme activity compared to the control plots, but there was no difference among amendments, while cultivar had no significant effect on the enzyme activity. In general, the addition of fertilizer and organic amendments had a significant impact on bacteria at every taxonomical level. The results indicated that Proteobacteria was the most dominant phylum identified, of which three of its classes (alphaproteobacteria, betaproteobacteria, gammaproteobacteria), as well as the class actinobacteria were the most prevalent in the class groups. This observation is consistent with the literature which has found that proteobacteria to be ubiquitous in the soil ecosystem. Several of the other classes like betaproteobacteria and gammaproteobacteria contain many ammonia-oxidizing bacteria (AOB) which play important in N cycling. The abundant concentration of Azospirilla spp.was also consistent as this species well known as nitrogen fixing bacteria which can account for sweet potato’s ability to grown in N deficient soils. Cultivars TU Purple, and Whatley/Lortan significantly impacted the Gemmatimonadetes at every taxonomical level suggesting that these cultivars produce exudates that may attract the bacteria. Bacteria belonging to phylum Gemmatimonadetes are frequently detected in a variety of environments and is noted as one of the nine most commonly found phyla in 16S rRNA gene libraries from soil. Bacteria belonging to the class alphaproteobacteria, such as sphingomonas spp. and novosphingobium spp., are also players in C cycling.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Paul, S. C., Githinji, L. J., Ankumah, R. O., Willian, K. R., and G. Pritchett, G. 2014. Sorption Behavior of Ibuprofen and Naproxen in Simulated Domestic Wastewater. Water, Air, & Soil Pollution, 225(1), 1-11.
- Type:
Theses/Dissertations
Status:
Awaiting Publication
Year Published:
2014
Citation:
Lindsey, Lauren. 2014. Investigating the short term impact of organic amendments on sweetpotato rhizosphere microbial communities in South Central Alabama organic farms. M.S. Thesis. Tuskegee University, Tuskegee, Alabama.p 98
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Progress 10/01/10 to 09/30/11
Outputs
OUTPUTS: Three studies were conducted to evaluate effect of land use on soil and water quality. In the first study, the efficacy of transgenic cotton plants transformed with the synthetic antimicrobial peptide D4E1 that has been demonstrated in greenhouse studies to confer tolerance to the fungal pathogens Aspergillus, Verticillium, Thielaviopsis and Fusarium was evaluated in firld trials. Two consecutive field studies were conducted with transformed cotton plants (Gossipium hirsutum cv. Coker 312) to examine the efficacy of this peptide on the control of Cotton Seedling Disease Complex. In 2008 and 2009, 150 x150 feet test plots, with a natural load of pathogens, were arranged in a completely randomized design and were assigned one of 3 isogenic lines of cotton transformed with D4E1 or a control line. Each transgenic line and control was then examined and evaluated to determine the level of infestation. The impact of the transgenic cotton plant on soil quality was examined by assessing the soil microbial diversity and phosphatase enzyme activity in the plots of the transformed cotton lines compared to the control. Soil was sampled eight times over the two growing season and the phosphomonoesterase and phosphodiesterase enzyme activity was measured using standard methods. Soil microbial diversity was measured by extracting whole DNA from soil followed by pyrosequencing. In the second study the effect of land use in two watersheds in the Alabama River Basin were evaluated using PLOAD, which is a submodel under EPA's BASINS program. The loadings of nitrogen and phosphorus in the two watersheds, Mulberry and Catoma Creek, was estimated using PLOAD. Loadings for total nitrogen (TN), total phosphorus (TP), orthophosphate (PO43-), nitrite (NO2-) and nitrate (NO3-) were estimated and the results were compared with those obtained from field sampling followed by laboratory analysis. Laboratory analysis for phosphate was done using the ascorbic acid method, while nitrate N was determined using automated cadmium reduction method. Total nitrogen and total phosphorus were analyzed using a peroxodisulfate oxidation method. In the third study, the contribution of sorption and biodegradation in the reduction in the concentration of pharmaceuticals in wastewater has been attributed was evaluated using two commnonly used drugs. The effect of pH and concentration on sorption Ibuprofen and Naproxen in simulated domestic waste water (SDWW) was evaluated using various sorption isotherms, viz., Freundlich, Langmuir and Redlich-Peterson. Batch experiments were conducted at various pH levels, viz., 3.5, 6.5, 7.5 and 8.5 and concentration, viz., 125, 250, 500, 750 and 1000 μg/L. PARTICIPANTS: Ramble Ankumah, Principal Investigator, Drs. K. Kpomblekou-A., D. Mortley and B. Vuaghan, Co-investigators, Lakisha Odom, Samir Paul and Dev Gurung, Graduate Students, K. Rajasekaran, and J, Carey, USDA-ARS, New Orleans. TARGET AUDIENCES: Presentation will be at Professional Agricultural Workers Conference. and Regional and National Meetings. Information is also shared with cooperative extension agents. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Results from the first study showed that all three transgenic cotton lines were more resistant to cotton seedling infestation than the non-transformed line. In year 2008, lines 358 and line 373, there was a significant reduction (p> 0.05) in disease symptoms and in 2009, a significant decrease (p>0.05) in disease symptoms was observed in lines 357 and 373. D4E1 was also found to have broad-spectrum antimicrobial action against many fungal orders (Ascomycete, Basidiomycete, Deuteromycete and Oomycetes) as well as bacterial pathogens Pseudomonas and Xanthomonas. No significant differences were observed between the transformed plants and their controls with respect to phosphate enzyme activities. In both sample years, acid phosphatase activity at the time of harvest was significantly different from other sample times. Those treatments containing transformed cotton plants expressing D4E1 had no significant difference in microbial diversity, species evenness and species diversity when compared to the control treatments. Fluctuations in the microbial population and diversity were observed, but the effects were temporal and not treatment associated. Shifts found in the microbial population could be attributed to environmental and plant factors more so than the introduction of the synthetic antimicrobial. In the second study, a positive significant correlation was observed between PLOAD and laboratory data for both Mulberry Creek watershed (r = 0.83) and Catoma Creek watershed (r = 0.90) demonstating that PLOAD can be used to assess land use effects of N and P on water quality. Furthermore, the spatial trends of NO2-/NO3-, PO43-, TN and TP concentrations for the laboratory data were similar to the concentrations estimated by PLOAD model in both Catoma and Mulberry Creek watersheds. Both watersheds had TN and TP values that exceeded the EPA limits of 0.69 mg L-1 for TN and 0.037 mg L-1 for TP for rivers and streams. Comparatively, Catoma Creek Watershed was found to be more impaired than Mulberry Creek Watershed. In the third study, sorption of both Ibuprofen and Naproxen from simulated waste water was higher at lower pH values. It was found that the data were comparatively well fitted to the Redlich-Peterson isotherm. The findings of this study suggested that both Ibuprofen and Naproxen can be removed from wastewater through sorption by lowering the pH to values lower than pKa and maintaining the concentration at an optimum value.
Publications
- Gurung, D, P. 2011. Assessing the Nitrogen and Phosphorus Loading in Two Watersheds of the Alabama River Basin Using PLOAD Model. M.S. Thesis, Tuskegee University, Tuskegee, AL. p.73.
- Gurung, D.P., L.J.M. Githinji and R.O. Ankumah. 2011. Assessing the Nitrogen Loadings intwo watersheds of Alabama River Basin using PLOAD Model. Page 155 to 158 in Proc. 67th Annual PAWC Conference. Tuskegee, AL.
- Keith, J., L.J. Odom, and R.O. Ankumah. 2011. Influences of Synthetic D4E1 on Phosphodiesterase Activity. 2011. ARD Biennial Meeting Program and Abstract Book, Atlanta, GA.(OSP-U-10, p. 135).
- Odom, L.J.. 2011. Assessing the impact of cotton transformed with anti-microbial synthetic peptide D4E1 on progression of cotton seedling disease, enzymatic activity and microbial diversity. Ph.D. Dissertation. Tuskegee University, Tuskegee, AL. p 148.
- Odom, L.J., R. Ankumah, C. Bonsi, M. Egnin, J. Jaynes, D. Mortley, K. Rajasekaran, and J, Carey. 2011. Effect of Transgenic Cotton Plants Transformed with Antimicrobial Synthetic Peptide D4E1 on Cotton Seedling Disease, Soil Microbial Diversity, and enzymatic Activity. Odom, L 2010. Agron. Abstr. [CD-ROM] American Society of Agronomy, Madison, WI.
- Paul, S. R., Ankumah, R.O., Githinji,L., Wilian, K., Prichett,G. and Russel. A. 2010. Evaluation of the Influence of pH on Sorption of Ibuprofen, and Naproxen in Simulated Domestic Waste Water. Agron. Abstr. [CD-ROM] American Society of Agronomy, Madison, WI.
- Paul, S. R. 2011. Evaluation of the influence of pH and concentrations on sorption of Ibuprofen and Naproxen in simulated domestic wastewater. M.S. Thesis, Tuskegee University, Tuskegee, AL. p. 84.
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Progress 10/01/09 to 09/30/10
Outputs
OUTPUTS: The effects of cotton plant genetically modified with the anti-microbial peptide D4E1 on soil phosphates and microbial diversity was evaluated. Phosphatase enzyme activities, per cent carbon content, pH and soil microbial communities under modified cotton and non-nonnon modified cotton systems were also evaluated. Three 150 x 150 ft test plots, over two field seasons, were arranged in a completely randomized design and were assigned either one of 3 lines of cotton seed transformed with D4E1 (designated 357, 358, and 373), a control line containing a GUS marker gene, or a non-transgenic control consisting of the parent variety. Evidence of disease symptoms was evaluated and the soil was randomly sampled, composited and subjected to DNA extraction, pyrosequencing and phosphatase enzyme assays. The results were statistically evaluated by means of analysis of variance using SAS statistical system. Surface water loadings of loadings of nitrogen and phosphorus in two watersheds in Alabama River Basin were assessed using PLOAD model. The PLOAD input parameters included land use, event mean concentration, annual precipitation, and ratio of storm producing runoff. PARTICIPANTS: Dr Ankumah was resposible for microbial diversity analysis. Dr. Kpomblekou-A. supervised soil sampling and measurement of soil physical and chemical parameters. Dr. Mortley was responsible for plant measurements. Drs. Vaughan and Ankumah supernised the water part of the project. TARGET AUDIENCES: Farmers, soil and plant scientists and NRCS. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Overall results show that introduction of D4E1 resulted in a decrease in disease symptoms (p>0.05) when compared to the control. Enzymatic activity and microbial diversity did show temporally-associated changes that were not treatment related. The introduction of D4E1 resulted in a significant reduction of disease symptoms; specifically in isogenic line 373. Phosphodiesterase activity was decreased in 2008 in isogenic line 357, while lines 358 and 373 did not show reduction in activity. In 2009, (with the exception of day 49) isogenic lines did not show a decrease in phosphodiesterase activity in comparison to the controls. There was no difference between the relative abundance of phyla found in the control versus the treatments containing D4E1, in both 2008 and 2009 growing seasons. Variations that were found in relative abundance were temporally associated, not associated with treatment. The only observed differences between relative abundance of Acidiobacteria and Actinobacteria seem to be effected by seasonal changes. This trend was also observed in phosphodiesterase activity suggesting that climatic variables may have major impact on these biological parameters. Differences in Acidiobacteria and Actinobacteria were observed but those differences were also temporal. Neither microbial diversity, species diversity nor species evenness appeared to be affected by the introduction of D4E1, any changes observed also appeared to be temporal. The PLOAD model outputs for the parameters of total nitrogen and total phosphorus in Mulberry Creek watershed were 1.19 milligrams per liter and 0.124 milligrams per liter respectively. Likewise, the PLOAD model outputs for the parameters of total nitrogen and total phosphorus in Catoma Creek watershed were 1.29 and 0.22 milligrams per liter respectively. The laboratory results of nitrate-nitrogen, phosphates, total nitrogen and total phosphorus in Mulberry Creek watershed were 0.57, 0.12 1.3, and 0.34 liter per milligrams respectively. Likewise, the lab results of nitrate-nitrogen, phosphates, total nitrogen and total phosphorus in Catoma Creek watershed were 0.58 , 0.20, 1.48 and 0.35 milligrams respectively. Most of the creeks were found significantly different total nitrogen and phosphrus. Catoma Creek watershed and Mulberry Creek watershed were found impaired as both of them exceeded the EPA recommendation standards of 0.69 miiligrams per liter for total nitrogen and 0.037 milligrams per liter for total phosphorus for river and stream. Comparatively, Catoma Creek watershed was found more polluted than Mulberry Creek watershed.
Publications
- Odom, L., Bonsi,C., Ankumah, R.O., Jaynes, J., Egnin, M., Ogden,L., and Mortley, D. 2010. Effect of Antimicrobial Peptide D4E1 on Infestation of Cotton Seedling Disease on Soil Microbial Diversity. Proc. 66th Annual Professional Agricultural Workers Conference, Pages 226-235, Tuskegee, AL
- Gurung, D., Ankumah, R.O., and Githinji, L. 2009. Assessing the Impact of Land Use Practices on Nitrogen and Phosphorus Loading in two Creeks in the Alabama River Basin Using PLOAD Model. Abstract 67th Annual Professional Workers Conference, Tuskegee, AL.
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Progress 10/01/08 to 09/30/09
Outputs
OUTPUTS: Relationship between landuse and poultry litter application were determined and related to major soil indices. Spatial distribution of enzyme activity as affected by landuse was generated using spatial analysis from data obtained from determination of phosphate enzyme activities. Soil samples were collected from a 0-15 cm depth. Subsamples were analyzed in triplicates for each sampling location for statistical comparisons of means. Means of those replicates were used for geostatistical analysis. Phosphomonoesterases (Acid and Alkaline) were determined using the method of Tabatabai and Bremner (1969) and phosphodiesterase was determined using the method described by Browman and Tabatabai (1978). Samples were analyzed for pH (1:2, soil water) with a pH meter, and from the 2-mm and less fraction duplicate 40 g sub samples were used for particle size anlysis (PSA). Microbial diversity and composition as influenced by land use and across landscape was generated using whole soil DNA extraction followed by denaturing gel electrophoresis or pyrosequencing. Data analyzed wetre in triplicates for significant statistical correlations (Pearson's), and differences in means were performed using Statistical Package for Social Science. All geostatistical analysis was assessed using geostatistical software package. Geostatistical input data was the resulting mean of three laboratory replicates of each field sample. TMDL on major watersheds along the Alabama River in the Black Belt of Alabama water accessed using P-load a sub of BASINS. Total Maximum Daily Loads (TMDL) were developed using P-load and compared to values obtained by direct sampling. A ten year reevaluation of private well quality in Geneva County in Alabama was initiated. PARTICIPANTS: Ramble O. Ankumah supervised the overall project and is responsible for supervising soil enzyme analysis. Kokoasse Kpomblekou-A was responsible for organic matter, phosphrus and nitrate analysis. Desmond Mortley and Barrett Vaughan are responsible for supervising field work on project. A number of masters and doctoral students are being trained as part of this project. Currently three masters students(Shantel King, Dave Gurung and Esthesis Smith) and two docroal students (Raymon Shange and Lakisha Odom) are working on this project. One master's student, Esther Haugabrooks, graduated in May 2009. TARGET AUDIENCES: Farmers, County Extension Agents, and Soils, Natural and Water Resources Professionals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
A significant difference was found between enzyme activities and percent carbon in wetland, transition, and upland soils. Percent organic carbon and phosphatase enzyme activities were higher in wetland soils compared to transition and upland soils. A strong positive correlation was observed between phosphatase enzyme activities and percent organic carbon, in agreement with by previous studies. Even though microbial diversity of the three treatment areas were not significantly different when data was pooled, significant differences were observed within transects and zones reflecting spatial variabilityCorrelations between enzyme activity and clay content suggested that other constituents held by clays may influence activity. Areas with the most exposure to animal manure, for example, pastured grazing area and litter storage areas, showed the highest levels of activities. Areas with the excessive litter layers, with the capacity for inhibitory action, for example, polyphenols from pine litter, heavy metals from poultry litter, showed the least amount of activity with the exception of alkaline phosphatase activity on forest floor and phosphodiesterase activity in the broiler house floor. pH reflected the same pattern emphasizing the pH dependence of enzyme activity. The soil enzymes measured in the current study showed strong to moderate spatial dependency, while modeling the empirical data relatively well. The physiochemcial composition of the soil microhabitat showed variance across the landscape and an influence on the enzymatic activity. Phosphatase enzyme activity was shown to be variable in their comparison to species richness of soil bacteria. Qualitatively and quantitatively, interpolated surfaces for enzymes seem to coincide with land use. Soil microbial communities showed interesting trends that coincide with the varying landscape and needs further analysis. Preliminary DGGE data suggested that poultry litter(PL)application may influence soils microbial community composition and diversity over time. Rates of application of PL affected the activities of the phosphomonestrases. TMDL values obtained using P-load seemed to be fairly correlated with the field data.
Publications
- Odom, L. , Ankumah, R., Bonsi, C, Cary, J., Jaynes, J, Rajasekaran, R., Egnin, M, Mortley, D, and Ogden, L. 2009. Effect of cotton plant genetically modified with an antimicrobial synthetic peptide D4E1 on soil microbial and enzyme activity. Agronomy Abstracts [CD-ROM] American Society of Agronomy, Madison, WI.
- Ankumah, R.O., and L. Githinji.2009. Use of soil enzyme activity as possible measures of carbon sequestration under different tillage and cropping practices. ESA Annual Conference, Albuquerque, NM, August 3-7, 2009.
- Githinji, L. , Giles, K., and Ankumah, R.O. 2009.Effect of tillage practices on organic carbon, pH, and bulk density and soil enzyme activity. Agronomy Abstracts [CD-ROM] American Society of Agronomy, Madison, WI.
- Hampton, M., Ankumah, R. O., and Githinji, L. 2009. Assessing nitrate contamination in private wells in the Black Belt counties of Alabama. Abstracts of the 15th Biennial Research Symposium of the Association of Research Directors, Atlanta, GA.
- Haugabrooks, E. 2009. Evaluation of soil enzyme activity and microbial diversity as measures of wetland function along a forested transect in Macon County, AL. M.S. Thesis. Tuskegee University, Tuskegee, AL.
- Haugabooks, E., Ankumah. R.O., Corley, M., McElhenney, W., Smith, R. and Githinji, L. 2009. Evaluation of soil enzyme activity and microbial diversity as measures of wetland function along a forested transect in Macon County, AL. Agronomy Abstracts. [CD-ROM], American Society of Agronomy, Madison, WI.
- King, S., Ankumah, R.O., Githinji, L., Rhoden, E., Bartlett, J.R. and Khan, V.A. 2009. Evaluation of rates of poultry litter application on selected phosphatase enzyme activities and microbial diversity. Agron. Abstr. [CD-ROM] American Society of Agronomy, Madison, WI.
- Shange, R., Ankumah, R. O. , Githinji, L. , and Zabawa R. 2009. Spatial variability of selected enzyme activity and soil properties across two agricultural landscapes. Agronomy Abstracts [CD-ROM] American Society of Agronomy, Madison, WI.
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Progress 10/01/07 to 09/30/08
Outputs
OUTPUTS: The effect of No-Till(NT) and Conventional Tillage (CT) practices on selected soil enzyme activities and their relationship to soil organic matter were evaluated. A split-plot design was used with two treatments, conventional till (CT) and no till (NT), replicated four times at two soil depths (0-5 cm and 5-15 cm). Samples were taken from the Tennessee Valley Research and Extension Center, Belle Mina, Alabama. The experimental plots were located on a long-term continuous cotton-corn system on a soil classified as Decatur silt loam (fine, kaolinitic, thermic rhodic paleudults). Soil samples were randomly collected within each plot, separated by depth (0-5 cm, 5-15 cm), composted for each depth to create a homogenous mixture. The samples were stored in cool boxes and later transported to the laboratory for analysis. Enzymatic assays for phosphomonoesterases (acid and alkaline) and phosphodiesterase were performed as described by Tabatabai and Bremner. Soil pH was determined for each sample by adding 10 grams of soil and 20 ml of de-ionized water into a specimen cup. The samples were swirled to mix and allowed to stand for ten minutes to equilibrate. Soil pH was then measured using a Fisher pH meter. Bulk density was determined by taking four undisturbed cores randomly from each plot and placing them in an oven at 105 degrees Celsius for 24 hours. The oven dry weight of the samples was determined and the volume of the cores calculated from their height and internal diameter. Bulk density was then calculated using the following formula: Bulk Density= Weight of Oven Dried Soil(g)/Volume of Soil (cm 3). Organic carbon was determined using high temperature combustion method. A presentation was made at the 66th Annual Professional Agriculture Workers Conference helh in Tuskegee Uiniversity. PARTICIPANTS: Ramble O. Ankumah supervised the overall project and is responsible for supervising soil enzyme analysis. Kokoasse Kpomblekou-A was responsible for organic matter, phosphrus and nitrate analysis. Desmond Mortley and Barrett Vaughan are responsible for supervising field work on project. Kalia Giles is a master's student in plant and soil science who is being trained under this project. TARGET AUDIENCES: Farmers, extension agents and state and federal agencies. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The results showed significant higher enzyme activity in NT compared to CT practices. Acid phosphomonoesterases levels were also significantly higher at 5-15 cm depths in the NT plots compared to CT. Percent organic carbon was significantly higher (p<0.01) in the NT and 0-5 depth compared to the CT and 5-15 cm depth. Soil bulk density was lower between 0 and 5 cm soil compared to between 5 and 15 cm for both CT and NT. The results showed a significant correlation (r=0.938 p<0.01) between the alkaline phosphomonoesterase and phosphodiesterase. There was a strong positive correlation between the organic matter and the phosphatase enzymes, the highest value being for the alkaline phosphomonoesterase (r=0.958 p<0.01). These results suggest that the phosphomono and diesterases may be possible candidates for evaluating carbon sequestration under various tillage practices. Research has shown that No-tillage practices increase soil organic matter content, improve soil structure and water retention, and serve as a nutrient reservoir for plant growth and substrate for soil microorganisms. This explains the higher percent organic carbon for the NT compared to the CT. In the NT plots, the percent organic carbon was higher for 0-5 cm depth compared to 5-15 cm depth suggesting organic matter build up. The percent organic carbon was relatively the same in CT plots for both depths which is attributed to the turning of soil during the CT practices leading to mixing of soil organic matter (SOM). The NT plots had higher percent organic carbon compared to the CT plots and higher enzyme activities. Furthermore, percent organic carbon was found to be positively correlated with enzyme activities. These results illustrate that enzyme activity could be used as a plausible surrogate for soil organic carbon and hence SOM.
Publications
- Giles, K, Githinji, L., Ankumah, R. and McElhenney, W. 2008 (abstracts). The effects of Tillage Practices on Selected Soil Enzyme Activities and Parameters. 66th Professional Agricultural Workers Conference, Tuskegee, Alabama. December, 2008
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