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Evaluation of the sustainability of grain production systems requires knowledge of long-term crop yields, and edge-of-field runoff volumes and water quality. When measured data are limited, computer simulation models —calibrated and validated with the available data— are well suited for this type of inquiry. In this study, the Agricultural Policy Environmental Extender (APEX) model was used to investigate how management affects crop yields, runoff volume, and water quality on claypan soils. Specific objectives were to determine the ability of APEX to simulate the variability of corn and soybean yields on claypan soils and the transport of dissolved-phase atrazine and nutrients via surface runoff; and how management affects long-term runoff and associated loss of these constituents. In spite of satisfactory model performance for corn yields and acceptable relative differences for soybean yields, the model was not capable of simulating the effects of management or landscape position on crop yields. Model performance was very good for runoff, and mostly satisfactory for dissolved constituents. Long-term simulation along with uncertainty analysis indicated that a no-till 3-year corn-soybean-wheat rotation with cover crops provides the most benefits to water quality by reducing nutrient transport in runoff. This system appeared to mitigate the negative effects of no-till on the surface transport of non-incorporated dissolved chemicals because of improved fertilizer management in terms of rate, placement, and timing of application. Cover crops appeared to reduce nitrate leaching compared to a 2-year no-till system. This research highlights the need for further research in crop growth modeling as inconsistent crop yield results undermine the usefulness of the model for making recommendations about management. Overall, the long-term simulations support the concept of multiple practices addressing tillage, fertilizer management, longer crop rotations, and use of cover crops to achieve desired environmental and production goals.
C. Baffaut; F. Ghidey; R.N. Lerch; N.R. Kitchen; K.A. Sudduth; E.J. Sadler. Long-term simulated runoff and water quality from grain cropping systems on restrictive layer soils. Agricultural Water Management 2018, 213, 36 -48.
AMA StyleC. Baffaut, F. Ghidey, R.N. Lerch, N.R. Kitchen, K.A. Sudduth, E.J. Sadler. Long-term simulated runoff and water quality from grain cropping systems on restrictive layer soils. Agricultural Water Management. 2018; 213 ():36-48.
Chicago/Turabian StyleC. Baffaut; F. Ghidey; R.N. Lerch; N.R. Kitchen; K.A. Sudduth; E.J. Sadler. 2018. "Long-term simulated runoff and water quality from grain cropping systems on restrictive layer soils." Agricultural Water Management 213, no. : 36-48.
Potential impacts of climate change on the hydrological components of the Goodwater Creek Experimental Watershed were assessed using climate datasets from the Coupled Model Intercomparison Project Phase 5 and Soil and Water Assessment Tool (SWAT). Historical and future ensembles of downscaled precipitation and temperature, and modeled water yield, surface runoff, and evapotranspiration, were compared. Ensemble SWAT results indicate increased springtime precipitation, water yield, surface runoff and a shift in evapotranspiration peak one month earlier in the future. To evaluate the performance of model spatial resolution, gridded surface runoff estimated by Lund–Potsdam–Jena managed Land (LPJmL) and Jena Diversity-Dynamic Global Vegetation model (JeDi-DGVM) were compared to SWAT. Long-term comparison shows a 6–8% higher average annual runoff prediction for LPJmL, and a 5–30% lower prediction for JeDi-DGVM, compared to SWAT. Although annual runoff showed little change for LPJmL, monthly runoff projection under-predicted peak runoff and over-predicted low runoff for LPJmL compared to SWAT. The reasons for these differences include differences in spatial resolution of model inputs and mathematical representation of the physical processes. Results indicate benefits of impact assessments at local scales with heterogeneous sets of parameters to adequately represent extreme conditions that are muted in global gridded model studies by spatial averaging over large study domains.
Sagar Gautam; Christine Costello; Claire Baffaut; Allen Thompson; Bohumil M. Svoma; Quang A. Phung; Edward J. Sadler. Assessing Long-Term Hydrological Impact of Climate Change Using an Ensemble Approach and Comparison with Global Gridded Model-A Case Study on Goodwater Creek Experimental Watershed. Water 2018, 10, 564 .
AMA StyleSagar Gautam, Christine Costello, Claire Baffaut, Allen Thompson, Bohumil M. Svoma, Quang A. Phung, Edward J. Sadler. Assessing Long-Term Hydrological Impact of Climate Change Using an Ensemble Approach and Comparison with Global Gridded Model-A Case Study on Goodwater Creek Experimental Watershed. Water. 2018; 10 (5):564.
Chicago/Turabian StyleSagar Gautam; Christine Costello; Claire Baffaut; Allen Thompson; Bohumil M. Svoma; Quang A. Phung; Edward J. Sadler. 2018. "Assessing Long-Term Hydrological Impact of Climate Change Using an Ensemble Approach and Comparison with Global Gridded Model-A Case Study on Goodwater Creek Experimental Watershed." Water 10, no. 5: 564.
The Agricultural Policy Environmental eXtender (APEX) model is capable of estimating edge-of-field water, nutrient, and sediment transport and is used to assess the environmental impacts of management practices. The current practice is to fully calibrate the model for each site simulation, a task that requires resources and data not always available. The objective of this study was to compare model performance for flow, sediment, and phosphorus transport under two parameterization schemes: a best professional judgment (BPJ) parameterization based on readily available data and a fully calibrated parameterization based on site-specific soil, weather, event flow, and water quality data. The analysis was conducted using 12 datasets at four locations representing poorly drained soils and row-crop production under different tillage systems. Model performance was based on the Nash–Sutcliffe efficiency (NSE), the coefficient of determination (r2) and the regression slope between simulated and measured annualized loads across all site years. Although the BPJ model performance for flow was acceptable (NSE = 0.7) at the annual time step, calibration improved it (NSE = 0.9). Acceptable simulation of sediment and total phosphorus transport (NSE = 0.5 and 0.9, respectively) was obtained only after full calibration at each site. Given the unacceptable performance of the BPJ approach, uncalibrated use of APEX for planning or management purposes may be misleading. Model calibration with water quality data prior to using APEX for simulating sediment and total phosphorus loss is essential. Copyright © 2017. . Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Claire Baffaut; Nathan O. Nelson; John A. Lory; G.M.M.M. Anomaa Senaviratne; Ammar B. Bhandari; Ranjith P. Udawatta; Daniel W. Sweeney; Matt J. Helmers; Mike W. Van Liew; Antonio P. Mallarino; Charles S. Wortmann. Multisite Evaluation of APEX for Water Quality: I. Best Professional Judgment Parameterization. Journal of Environmental Quality 2017, 46, 1323 -1331.
AMA StyleClaire Baffaut, Nathan O. Nelson, John A. Lory, G.M.M.M. Anomaa Senaviratne, Ammar B. Bhandari, Ranjith P. Udawatta, Daniel W. Sweeney, Matt J. Helmers, Mike W. Van Liew, Antonio P. Mallarino, Charles S. Wortmann. Multisite Evaluation of APEX for Water Quality: I. Best Professional Judgment Parameterization. Journal of Environmental Quality. 2017; 46 (6):1323-1331.
Chicago/Turabian StyleClaire Baffaut; Nathan O. Nelson; John A. Lory; G.M.M.M. Anomaa Senaviratne; Ammar B. Bhandari; Ranjith P. Udawatta; Daniel W. Sweeney; Matt J. Helmers; Mike W. Van Liew; Antonio P. Mallarino; Charles S. Wortmann. 2017. "Multisite Evaluation of APEX for Water Quality: I. Best Professional Judgment Parameterization." Journal of Environmental Quality 46, no. 6: 1323-1331.
The Conservation Effects Assessment Project (CEAP) was initiated in 2002 to quantify the potential benefits of conservation management practices throughout the nation. Within the Central Claypan Region of Missouri, the Salt River Basin was selected as a benchmark watershed for soil and water quality assessments. This study focuses on two objectives: (1) assessing soil quality for 15 different annual cropping and perennial vegetation systems typically employed in this region, and (2) evaluating relationships among multiple measured soil quality indicators (SQIs). Management practices included annual versus perennial vegetation, and varying grass species composition (cool-season versus warm-season), tillage intensity (no-till versus mulch-till), biomass removal, rotation phase, crop rotation (corn [Zea mays L.]–soybean [Glycine max L. Merr] versus corn–soybean–wheat [Triticum aestivum L.]) and incorporation of cover crops into the rotation. Soil samples were obtained in 2008 from 0 to 5 cm (0 to 2 in) and 5 to 15 cm (2 to 6 in) depth layers. Ten biological, physical, chemical, and nutrient SQIs were measured and scored using the Soil Management Assessment Framework (SMAF). Across SQIs, biological and physical indicators were the most sensitive to management effects, reflecting significant differences in organic carbon (C), mineralizable nitrogen (N), β-glucosidase, and bulk density. In the 0 to 5 cm layer, perennial systems demonstrated the greatest SMAF scores, ranging from 93% to 97% of the soil's inherent potential. Scores for annual cropping systems ranged from 78% to 92%: diversified no-till, corn–soybean–wheat rotation with cover crops (92%) > no-till, corn–soybean rotation without cover crops (88%) > mulch-till corn–soybean rotation without cover crops (84%). Conversely, in the 5 to 15 cm layer, no-till cropping systems scored lower for overall soil function (58% to 61%) than mulch-till systems (65% to 66%). In the 0 to 5 cm layer, biological soil quality under the diversified no-till system with cover crops was 11% greater than under no-till without cover crops, and 20% greater than under mulch-till without cover crops. The effect of rotation phase was primarily reflected in 64% lower mineralizable N following corn relative to soybean. Additionally, soil nutrient function was significantly affected by biomass removal. The results of this study demonstrate that the benefits of conservation management practices extend beyond soil erosion reduction and improved water quality by highlighting the potential for enhanced soil quality, especially biological soil function. In particular, implementing conservation management practices on marginal and degraded soils in the claypan region can enhance long-term sustainability in annual cropping systems and working grasslands through improved soil quality.
K. S. Veum; R. J. Kremer; K. A. Sudduth; N. R. Kitchen; R. N. Lerch; C. Baffaut; D. E. Stott; D. L. Karlen; Edward Sadler. Conservation effects on soil quality indicators in the Missouri Salt River Basin. Journal of Soil and Water Conservation 2015, 70, 232 -246.
AMA StyleK. S. Veum, R. J. Kremer, K. A. Sudduth, N. R. Kitchen, R. N. Lerch, C. Baffaut, D. E. Stott, D. L. Karlen, Edward Sadler. Conservation effects on soil quality indicators in the Missouri Salt River Basin. Journal of Soil and Water Conservation. 2015; 70 (4):232-246.
Chicago/Turabian StyleK. S. Veum; R. J. Kremer; K. A. Sudduth; N. R. Kitchen; R. N. Lerch; C. Baffaut; D. E. Stott; D. L. Karlen; Edward Sadler. 2015. "Conservation effects on soil quality indicators in the Missouri Salt River Basin." Journal of Soil and Water Conservation 70, no. 4: 232-246.
Long-term monitoring data from agricultural watersheds are needed to determine if efforts to reduce nutrient transport from crop and pasture land have been effective. Goodwater Creek Experimental Watershed (GCEW), located in northeastern Missouri, is a high-runoff-potential watershed dominated by claypan soils. The objectives of this study were to: (i) summarize dissolved NH-N, NO-N, and PO-P flow-weighted concentrations (FWC), daily loads, and yields (unit area loads) in GCEW from 1992 to 2010; (ii) assess time trends and relationships between precipitation, land use, and fertilizer inputs and nutrient transport; and (iii) provide context to the GCEW data by comparisons with other Corn Belt watersheds. Significant declines in annual and quarterly FWCs and yields occurred for all three nutrient species during the study, and the decreases were most evident for NO-N. Substantial decreases in first- and fourth-quarter NO-N FWCs and daily loads and modest decreases in first-quarter PO-P daily loads were observed. Declines in NO-N and PO-P transport were attributed to decreased winter wheat ( L.) and increased corn ( L.) production that shifted fertilizer application from fall to spring as well as to improved management, such as increased use of incorporation. Regression models and correlation analyses indicated that precipitation, land use, and fertilizer inputs were critical factors controlling transport. Within the Mississippi River Basin, NO-N yields in GCEW were much lower than in tile-drained areas, but PO-P yields were among the highest in the basin. Overall, results demonstrated that reductions in fall-applied fertilizer and improved fertilizer management reduced N and P transport in GCEW.
R. N. Lerch; C. Baffaut; N. R. Kitchen; Edward Sadler. Long-Term Agroecosystem Research in the Central Mississippi River Basin: Dissolved Nitrogen and Phosphorus Transport in a High-Runoff-Potential Watershed. Journal of Environmental Quality 2015, 44, 44 -57.
AMA StyleR. N. Lerch, C. Baffaut, N. R. Kitchen, Edward Sadler. Long-Term Agroecosystem Research in the Central Mississippi River Basin: Dissolved Nitrogen and Phosphorus Transport in a High-Runoff-Potential Watershed. Journal of Environmental Quality. 2015; 44 (1):44-57.
Chicago/Turabian StyleR. N. Lerch; C. Baffaut; N. R. Kitchen; Edward Sadler. 2015. "Long-Term Agroecosystem Research in the Central Mississippi River Basin: Dissolved Nitrogen and Phosphorus Transport in a High-Runoff-Potential Watershed." Journal of Environmental Quality 44, no. 1: 44-57.
Goodwater Creek Experimental Watershed (GCEW) has been the focus area of a long-term effort to document the extent of and to understand the factors controlling herbicide transport. We document the datasets generated in the 20-yr-long research effort to study the transport of herbicides to surface and groundwater in the GCEW. This long-term effort was augmented with a spatially broad effort within the Central Mississippi River Basin encompassing 12 related claypan watersheds in the Salt River Basin, two cave streams on the fringe of the Central Claypan Areas in the Bonne Femme watershed, and 95 streams in northern Missouri and southern Iowa. Details of the analytical methods, periods of record, number of samples, study locations, and means of accessing these data are provided. In addition, a brief overview of significant findings is presented. A key finding was that near-surface restrictive soil layers, such as argillic horizons of smectitic mineralogy, result in greater herbicide transport than soils with high percolation and low clay content. Because of this, streams in the claypan soil watersheds of northeastern Missouri have exceptionally high herbicide concentrations and relative loads compared with other areas of the Corn Belt.
R. N. Lerch; C. Baffaut; E. J. Sadler; R. J. Kremer. Long-Term Agroecosystem Research in the Central Mississippi River Basin: Goodwater Creek Experimental Watershed and Regional Herbicide Water Quality Data. Journal of Environmental Quality 2015, 44, 28 -36.
AMA StyleR. N. Lerch, C. Baffaut, E. J. Sadler, R. J. Kremer. Long-Term Agroecosystem Research in the Central Mississippi River Basin: Goodwater Creek Experimental Watershed and Regional Herbicide Water Quality Data. Journal of Environmental Quality. 2015; 44 (1):28-36.
Chicago/Turabian StyleR. N. Lerch; C. Baffaut; E. J. Sadler; R. J. Kremer. 2015. "Long-Term Agroecosystem Research in the Central Mississippi River Basin: Goodwater Creek Experimental Watershed and Regional Herbicide Water Quality Data." Journal of Environmental Quality 44, no. 1: 28-36.
We document the 20-yr-long research effort to study the transport of N and P to surface and groundwater in Goodwater Creek Experimental Watershed. We also document related efforts in nearby claypan watersheds and watersheds with contrasting soil and hydrologic conditions across the northern Missouri-southern Iowa region. Details of the analytical methods, instrumentation, method detection limits, and quality assurance program used to generate the data are described along with a brief overview of significant findings. Nutrient concentrations in streams were in the range associated with nuisance algal growth and presumed loss of aquatic invertebrate diversity. Incorporation of fertilizers was shown to be the most effective practice for reducing nutrient transport in runoff. Despite the claypan soils, NO leaching was a major fate for fertilizer N, and significant contamination of the glacial till aquifer has occurred when long-term fertilizer and manure N inputs exceeded crop N requirements. A key finding of these studies was that field areas with the poorest crop growth were also the most vulnerable to nutrient as well as sediment and herbicide transport.
R. N. Lerch; N. R. Kitchen; C. Baffaut; E. D. Vories. Long-Term Agroecosystem Research in the Central Mississippi River Basin: Goodwater Creek Experimental Watershed and Regional Nutrient Water Quality Data. Journal of Environmental Quality 2015, 44, 37 -43.
AMA StyleR. N. Lerch, N. R. Kitchen, C. Baffaut, E. D. Vories. Long-Term Agroecosystem Research in the Central Mississippi River Basin: Goodwater Creek Experimental Watershed and Regional Nutrient Water Quality Data. Journal of Environmental Quality. 2015; 44 (1):37-43.
Chicago/Turabian StyleR. N. Lerch; N. R. Kitchen; C. Baffaut; E. D. Vories. 2015. "Long-Term Agroecosystem Research in the Central Mississippi River Basin: Goodwater Creek Experimental Watershed and Regional Nutrient Water Quality Data." Journal of Environmental Quality 44, no. 1: 37-43.
Claire Baffaut; Fessehaie Ghidey; Kenneth A. Sudduth; Robert N. Lerch; E. John Sadler. Long-term suspended sediment transport in the Goodwater Creek Experimental Watershed and Salt River Basin, Missouri, USA. Water Resources Research 2013, 49, 7827 -7830.
AMA StyleClaire Baffaut, Fessehaie Ghidey, Kenneth A. Sudduth, Robert N. Lerch, E. John Sadler. Long-term suspended sediment transport in the Goodwater Creek Experimental Watershed and Salt River Basin, Missouri, USA. Water Resources Research. 2013; 49 (11):7827-7830.
Chicago/Turabian StyleClaire Baffaut; Fessehaie Ghidey; Kenneth A. Sudduth; Robert N. Lerch; E. John Sadler. 2013. "Long-term suspended sediment transport in the Goodwater Creek Experimental Watershed and Salt River Basin, Missouri, USA." Water Resources Research 49, no. 11: 7827-7830.
Targeting critical management areas (CMAs) within cropped fields is essential to maximize production while implementing alternative management practices that will minimize impacts on water quality. The objective of this study was to develop physically based indices to identify CMAs in a 35 ha (88 ac) field characterized by a restrictive clay layer occurring within the upper 15 to 100 cm (6 to 40 in) and under a corn (Zea mays L.)–soybean (Glycine max L.) crop rotation since 1991. Thirty-five subareas were defined based on slope, depth to claypan (CD), and soil mapping units. The Agricultural Policy/Environmental eXtender (APEX) model was calibrated and validated from 1993 to 2002 using measured runoff, sediment, and atrazine loads, and crop yields. CMAs were delineated based on simulated subarea runoff, sediment, and atrazine loads. Correlation analysis was performed between simulated output by subarea and physical parameters, including CD, surface saturated hydraulic conductivity (Ksat), and subarea slope (SL). Two indices were developed, the Conductivity Claypan Index (CCI; CD ×Ksat ÷SL) and the Claypan Index (CPI; CD ÷ SL), to correlate with simulated crop yields, runoff, atrazine, and sediment loads. Together, these indices captured 100% of CMAs for simulated runoff and sediment yield and 60% of CMAs for simulated atrazine in surface runoff, as predicted by APEX. These critical areas also matched lower corn productivity areas. Management scenarios were simulated that differentiated the management of the CMAs from the rest of the field. Indices, such as these, for identifying areas of higher environmental risk and lower productivity could provide objective criteria for effective targeting of best management practices.
A. Mudgal; C. Baffaut; S. H. Anderson; Edward Sadler; N. R. Kitchen; K. A. Sudduth; R. N. Lerch. Using the Agricultural Policy/Environmental eXtender to develop and validate physically based indices for the delineation of critical management areas. Journal of Soil and Water Conservation 2012, 67, 284 -299.
AMA StyleA. Mudgal, C. Baffaut, S. H. Anderson, Edward Sadler, N. R. Kitchen, K. A. Sudduth, R. N. Lerch. Using the Agricultural Policy/Environmental eXtender to develop and validate physically based indices for the delineation of critical management areas. Journal of Soil and Water Conservation. 2012; 67 (4):284-299.
Chicago/Turabian StyleA. Mudgal; C. Baffaut; S. H. Anderson; Edward Sadler; N. R. Kitchen; K. A. Sudduth; R. N. Lerch. 2012. "Using the Agricultural Policy/Environmental eXtender to develop and validate physically based indices for the delineation of critical management areas." Journal of Soil and Water Conservation 67, no. 4: 284-299.
R.N. Lerch; E.J. Sadler; C. Baffaut; N.R. Kitchen; K.A. Sudduth. Herbicide Transport in Goodwater Creek Experimental Watershed: II. Long-Term Research on Acetochlor, Alachlor, Metolachlor, and Metribuzin1. JAWRA Journal of the American Water Resources Association 2010, 47, 224 -238.
AMA StyleR.N. Lerch, E.J. Sadler, C. Baffaut, N.R. Kitchen, K.A. Sudduth. Herbicide Transport in Goodwater Creek Experimental Watershed: II. Long-Term Research on Acetochlor, Alachlor, Metolachlor, and Metribuzin1. JAWRA Journal of the American Water Resources Association. 2010; 47 (2):224-238.
Chicago/Turabian StyleR.N. Lerch; E.J. Sadler; C. Baffaut; N.R. Kitchen; K.A. Sudduth. 2010. "Herbicide Transport in Goodwater Creek Experimental Watershed: II. Long-Term Research on Acetochlor, Alachlor, Metolachlor, and Metribuzin1." JAWRA Journal of the American Water Resources Association 47, no. 2: 224-238.
R.N. Lerch; E.J. Sadler; K.A. Sudduth; C. Baffaut; N.R. Kitchen. Herbicide Transport in Goodwater Creek ExperimentalWatershed: I. Long-Term Research on Atrazine1. JAWRA Journal of the American Water Resources Association 2010, 47, 209 -223.
AMA StyleR.N. Lerch, E.J. Sadler, K.A. Sudduth, C. Baffaut, N.R. Kitchen. Herbicide Transport in Goodwater Creek ExperimentalWatershed: I. Long-Term Research on Atrazine1. JAWRA Journal of the American Water Resources Association. 2010; 47 (2):209-223.
Chicago/Turabian StyleR.N. Lerch; E.J. Sadler; K.A. Sudduth; C. Baffaut; N.R. Kitchen. 2010. "Herbicide Transport in Goodwater Creek ExperimentalWatershed: I. Long-Term Research on Atrazine1." JAWRA Journal of the American Water Resources Association 47, no. 2: 209-223.
Various land management decisions are based on local soil properties. These soil properties include average values from soil characterization for each soil series. In reality, these properties might be variable due to substantially different management, even for similar soil series. This study was conducted to test the hypothesis that for claypan soils, hydraulic properties can be significantly affected by long-term soil and crop management. Sampling was conducted during the summer of 2008 from two fields with Mexico silt loam (Vertic Epiaqualfs). One field has been under continuous row crop cultivation for over 100 years (Field), while the other field is a native prairie that has never been tilled (Tucker Prairie). Soil cores (76 × 76 mm [3.0 × 3.0 in]) from six replicate locations from each field were sampled to a 60 cm (24 in) depth at 10 cm (3.9 in) intervals. Samples were analyzed for bulk density, saturated hydraulic conductivity (Ksat), soil water retention, and pore-size distributions. Values of coarse (60 to 1,000 μm [0.0024 to 0.039 in] effective diameter) and fine mesoporosity (10 to 60 μm [0.00039 to 0.0024 in] effective diameter) for the Field site (0.044 and 0.053 m3 m−3 [0.044 and 0.053 in3 in−3]) were almost half those values from the Tucker Prairie site (0.081 and 0.086 m3 m−3 [0.081 and 0.086 in3 in−3]). The geometric mean value of Ksat was 57 times higher in the native prairie site (316 mm h−1 [12.4 in hr−1]) than in the cropped field (5.55 mm h−1 [0.219 in hr−1]) for the first 10 cm (3.9 in) interval. Differences in Ksat values were partly explained by the significant differences in pore-size distributions. The bulk density of the surface layer at the Tucker Prairie site (0.81 g cm−3 [50.6 lb ft−3]) was two-thirds of the value at the Field site (1.44 g cm−3 [89.9 lb ft−3]), and was significantly different throughout the soil profile, except for the 20 to 30 cm (7.9 to 12 in) depth. These results show that row crop management and its effect on soil loss have significantly altered the hydraulic properties for this soil. Results from this study increase our understanding of the effects of long-term soil management on soil hydraulic properties.
A. Mudgal; S. H. Anderson; C. Baffaut; N. R. Kitchen; Edward Sadler. Effects of long-term soil and crop management on soil hydraulic properties for claypan soils. Journal of Soil and Water Conservation 2010, 65, 393 -403.
AMA StyleA. Mudgal, S. H. Anderson, C. Baffaut, N. R. Kitchen, Edward Sadler. Effects of long-term soil and crop management on soil hydraulic properties for claypan soils. Journal of Soil and Water Conservation. 2010; 65 (6):393-403.
Chicago/Turabian StyleA. Mudgal; S. H. Anderson; C. Baffaut; N. R. Kitchen; Edward Sadler. 2010. "Effects of long-term soil and crop management on soil hydraulic properties for claypan soils." Journal of Soil and Water Conservation 65, no. 6: 393-403.
R.N. Lerch; Edward Sadler; N.R. Kitchen; K.A. Sudduth; R.J. Kremer; D.B. Myers; C. Baffaut; S.H. Anderson; C.-H. Lin. Overview of the Mark Twain Lake/Salt River Basin Conservation Effects Assessment Project. Journal of Soil and Water Conservation 2008, 63, 345 -359.
AMA StyleR.N. Lerch, Edward Sadler, N.R. Kitchen, K.A. Sudduth, R.J. Kremer, D.B. Myers, C. Baffaut, S.H. Anderson, C.-H. Lin. Overview of the Mark Twain Lake/Salt River Basin Conservation Effects Assessment Project. Journal of Soil and Water Conservation. 2008; 63 (6):345-359.
Chicago/Turabian StyleR.N. Lerch; Edward Sadler; N.R. Kitchen; K.A. Sudduth; R.J. Kremer; D.B. Myers; C. Baffaut; S.H. Anderson; C.-H. Lin. 2008. "Overview of the Mark Twain Lake/Salt River Basin Conservation Effects Assessment Project." Journal of Soil and Water Conservation 63, no. 6: 345-359.