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United States Department of Agriculture

Agricultural Research Service

SWRC Bulletin (Winter 2012)
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The SWRC Bulletin

Sound Science for Water Decisions

Winter 2012 

Highlight from Recently Published Research:

USDA, 2011.  Soil and Water Resources Conservation Act (RCA) Appraisal, 100 p.


"The Soil and Water Resources Conservation Act (RCA) provides the USDA broad strategic assessment and planning authority for the conservation, protection, and enhancement of soil, water, and related natural resources” ( As part of the recently published 2011 RCA appraisal, the Automated Geospatial Watershed Assessment (AGWA) tool and the KINEROS2 watershed models, both developed by the SWRC, was used in several settings to estimate the effects of common rangeland conservation practices.  In one case, simulations were performed on the USDA-ARS Walnut Gulch Experimental Sub-Watershed #4 before and after hypothetical “brush” removal and reseeding of the entire watershed to convert it to grass cover using the 5 year, 30 minute design rainfall event.  Results, illustrated in the figure above indicated large decreases in peak flow (mm/hr) and peak sediment yield (kg/s) after the watershed was converted to grass.  This type of analysis provides land managers with the ability to determine which areas are better suited for land cover modification for management purposes such as brush management for fire control or grazing land improvement as well as the spatial location and magnitude of the consequences of the conservation practices.

Latest Science Results (not yet published)

(click on title for more information)

The Role of Water Subsidy on Vegetation Dynamics in a Semiarid Grassland Catchment: Comparison between Field Measurements and 3-D Ecohydrological Modeling


Modern pasture monitoring: An example from the Balkhash region of Kazakhstan


Sediment source identification in a semiarid watershed at soil mapping unit scales


Hydrologic response to pulse storm events during a native to exotic transition in a semiarid grassland


A radarsat-2 quad-polarized time series for monitoring crop and soil conditions in Barrax, Spain


Extending results from agricultural fields with intensively monitored data to surrounding areas for water quality management


Energy exchange and evapotranspiration over two temperate semi-arid grasslands in North America


Invasion of shrubland by exotic grasses:  Ecohydrological consequences in cold vs. warm deserts


Thermal Optimality of Net Ecosystem Exchange of Carbon Dioxide


Water-use-efficiency of annual- and bunchgrass-dominated savanna intercanopy space


Convergence of Dynamic Vegetation Net Productivity Responses to Precipitation Variability from 10 Years of MODIS


The Potential of Carbonyl Sulfide as a Proxy for Gross Primary Production at Flux Tower Sites


An Integrated Model Framework of Catchment-Scale Ecohydrological Processes





Modeling climate change effects on runoff and soil erosion in southeastern Arizona rangelands and implications for mitigation with rangeland conservation practices


Effects of antecedent soil moisture on runoff modeling in small semiarid watersheds of southeastern Arizona


Opportunities to Engage with NASA’s Soil Moisture Active Passive (SMAP) Mission Applications


The Soil Moisture Active Passive (SMAP) Applications Activity


Shrub encroachment alters sensitivity of soil respiration to temperature and moisture


Understanding ecohydrological connectivity in savannas: A system dynamics modeling approach


DevTreks:  Social budgeting software to improve agricultural economic data collection


Commonalities of carbon dioxide exchange in semiarid regions with monsoon and Mediterranean climates


Coupling Diffusion and Maximum Entropy Models to Estimate Thermal Inertia and Soil Moisture


How do more extreme rainfall regimes affect ecosystem fluxes in seasonally water-limited

Northern hemisphere temperate shrublands and forests?


Evaluating the increase in storm runoff from residential development in a semi-arid environment using the KINEROS2 modeling framework


Quantification of terrestrial ecosystem carbon dynamics in the conterminous United States combining a process-based biogeochemical model and MODIS and AmeriFlux data


Environmental Controls on Ecosystem Respiration in Drylands: The Role of the

Vertical Distribution of Soil Moisture


A sediment budget for a small semiarid Watershed in southeastern Arizona, USA 


Ecosystem gas Exchange in native and non-native desert grassland bunchgrasses


Assessing satellite-based rainfall estimates in semi-arid Watershed using the USDA-ARS Walnut Gullch gauge network and TRMM-PR


A comparison of two stream gauging systems for measuring runoff and sediment yield on semi-arid watershed


Mapping total vegetation fractional cover across western rangelands with the MODIS sensor       


Effect of small-scale spatial variability of precipitation measurements on synthetic weather generation and outputs of a runoff and soil erosion model


Scales and Erosion


Sediment tracers in water erosion studies: Current approaches and challenges


On the Effects of Improved Cross-Section Representation in One Dimensional Flow Routing Models Applied to Ephemeral Rivers


National assessment of soil erosion on non-federal rangelands


Evidence for positive and negative soil moisture-vegetation feedbacks across southwestern U.S. deserts

Papers Published 2nd Half 2010 - 2011:

Hamerlynck, E., McAuliffe, J.R. 2010. Growth and foliar d15N of a Mojave desert shrub in relation to soil hydrological dynamics. Journal of Arid Environments. 74: 1569-1571. (150 KB PDF)

Scott, R.L., Hamerlynck, E.P., Jenerette, G.D., Moran, M.S., Barron-Gafford, G.A. 2010. Carbon dioxide exchange in a semidesert grassland responding through drought-induced vegetation change. Journal of Geophysical Research - [Biogeosciences]. 15:1-12. (657 KB PDF)

Brand, L.A., Stromberg, J.C., Goodrich, D.C., Dixon, M.D., Lansey, K., Kang, D., Brookshire, D.S., Cerasale, D.J. 2010. Projecting avian response to linked changes in groundwater and riparian floodplain vegetation along a dryland river: a scenario analysis. Ecohydrology. p.1-13. (441 KB PDF)

Moran, M.S., Hamerlynck, E.P., Scott, R.L., Stone, J.J., Holifield Collins, C.D., Keefer, T.O., Bryant, R.B., DeYoung, L., Nearing, G.S., Sugg, Z., Hymer. D.C. 2010. Hydrologic response to precipitation pulses under and between shrubs in the Chihuahuan Desert, Arizona. Water Resources Research. 46:1-12. (477 KB PDF)

Moran, M.S., O'Neill P.E., Entekhabi, D., Njoku, E.G., Kellogg, K.H. 2010. Fostering applications opportunities for the NASA Soil Moisture Active Passive (SMAP) Mission. Proceedings of the 2010 IEEE International Geoscience and Remote Sensing Symposium, July 25, 2010, Honoulu, HI. , pp. 2571-2574. (36 KB PDF)

Xiao, J, Zhuang, Q, Law, B.E., Baldocchi, D.D., Chen, J., Richardson, A.D., Melillo, J.M., Davis, K.J., Hollinger, D.Y., Wharton, S., Oren, R., Noormets, A., Fischer, M.L., Verma, S.B., Cook, D.R., Sun, G., McNulty. S., Wofsy, S.C., Bolstad, P.V., Burns, S.P., Curtis, P.S., Drake, B.G., Falk, M., Foster, D.R., Gu, L., Hadley, J.L., Katul, G.G., Litvak, M., Ma, S., Martin, T.A., Matamala, R., Meyers, T.P., Monson, R.K., Munder, J.W., Oechel, W.C., Paw, U.K.T., Schmid, H.P., Scott, R.L., Starr, G., Suyker, A.E., Torn, M.S. 2010. Assessing net ecosystem carbon exchange of U.S. terrestrial ecosystems by integrating eddy covariance flux measurements and satellite observations. Agricultural and Forest Meteorology. 151: 60-69. (2 MB PDF)

Polyakov, V., Nearing, M.A., Nichols, M.H., Scott, R.L., Stone, J.J., McClaran, M. 2010. Runoff and sediment yields from small semi-arid watersheds in southern Arizona. Water Resources Research. 46: 1-12. (294 KB PDF)

Polyakov, V., Nearing, M.A., Stone, J.J., Hamerlynck, E.P., Nichols, M.H., Holifield Collins, C., Scott, R.L. 2010. Runoff and erosional response to a drought-induced shift in a desert grassland community composition. J. Geophys. Res. 115, G04027. (247 KB PDF)

Barron-Gafford, G.A., Scott, R.L., Jenerette, G.D., Huxman, T.E. 2011. The relative controls of temperature, soil moisture, and plant functional group on soil CO2 efflux at diel, seasonal, and annual scales. Journal of Geophysical Research - Biogeosciences. 116: 1-16. (2 MB PDF)

Godrich, D.C., Unkrich, C.L., Smith, R.E., Guertin, D.P., Hernandez, M., Burns, I.A., Massart, J., Levick, L., Miler, S.N., Semmens, D., Kepner,W.G. 2010. THE AGWA - KINEROS suite of modeling tools. American Soceity of Civil Engineers Water Resources Conference Proceedings (1.90 MB PDF)

Yuan, W., Luo, Y., Liang, S., Yu, G., Niu, S., Stoy, P., Chen, J., Desai, A.R., Lindroth, A., Gough, C.M., Ceulemans, R., Arain, A., Bernhofer,C., Cook, B., Cook, D.R., Dragoni, D., Gielen, B., Janssens, I.A., Longdoz, B., Liu, H., Lund, M., Matteucci, G., Moors, E., Scott, R.L., Seufert, G., Varner, R. 2011. Thermal adaptation of net ecosystem exchange. Biogeosciences. 8: 1453-1463, doi:10.5194/bg-8-1453-2011. (3 MB PDF)

Guertin, D.P., Goodrich, D.C. 2011. The future role of information technology in erosion modeling. Chap. 17 In: Handbook of Erosion Modelling, Morgan, R.P.C. and Nearing, M. (Eds.), p. 324-338. Wiley-Blackwell, 416 p. (1 MB PDF)

Gilimonov, T.G., Aires, L., Zarcza, Z,, Baron, V.S., Belelli, L., Beringer, J., Billesbach, D., Bonal, D., Bradford, J., Ceschia, E., Cook, D., Corradi, C., Frank, A., Gianelle, D., Gimeno, C., Gruenwald, T., Haiqiang, G., Hanan, N,, Haszpra, L., Heilman, J., Jacobs, A., Jones, M.B., Johnson, D.A., Kiely, G., Shenggong, L., Magliulo, V., Moors, E., Nagy, Z,, Nasyrov, M., Owensby, C., Pinter,K., Pio, C., Reichstein, M., Sanz, M.J., Scott, R.L., Soussana, J.F., Stoy, P.C., Svejcar, T., Tuba, Z., Zhou, G. 2010. Productivity, Respiration, and Light -Response Parameters of World Grassland and Agrecosystems Derived From Flux=Tower Measurements. Rangeland Ecology and Management. 63:16-39. (1.68 MB PDF)

Nearing, G.S., Moran, M.S., Holifield Collins, C., Thorp, K.R., Slack, S.C. 2010. An improved strategy for assimilating synthetic aperture radar imagery into modeled estimations of soil moisture through parameter optimization. Remote Sensing of Environment 114: 2564–2574. (857 KB PDF)

Goodrich, D.C., Guertin, D.P.,, Burns, I.S., Nearing, M.A., Stone, J.J., Wei, H., Heilman, P., Hernandez, M., Spaeth, K., Pierson, F., Paige, G.B., Miller, S.N., Kepner, W.G., Ruyle, G., McClaran, M.P., Weltz, M.A., Jolley, L. 2011. AGWA – R: The Automated Geospatial Watershed Assessment Tool for rangelands. Rangelands. Vol. 33, No. 4, pp. 41-47. (536 KB PDF)

Chen, M., Zhuang, Q., Cook, D.R., Coulter, R., Pekour, R., Scott, R.L., Munger, J.W., Bible, K. 2011. Quantification of terrestrial ecosystem carbon dynamics in the conterminous United States combining a process-based biogeochemical model and MODIS and AmeriFlux data. Biogeosciences. 8:2665-2688. (622 KB PDF)

Moran, M.S., Alonso, L., Moreno, J., Cendrero Mateo, M.P., de la Cruz, F., Montoro, A. (Not yet published). A radarsat-2 quad-polarized time series for monitoring crop and soil conditions in Barrax, Spain. IEEE Transactions on Geoscience and Remote Sensing

Cavanaugh, M., Kurc, S.A., Scott, R.L. 2011. Evapotranspiration partitioning in semiarid shrubland ecosystems: a two-site evaluation of soil moisture control on transpiration. Ecohydrology. 4:671–681. (330 KB PDF)

McMilian, H., Cark, M., Woods, R., Duncan, M., Srinivansani, M.S., Western, A., Goodrich,D.C. 2010. Improving perceptual and conceptual hydrological models using data from small basins. IAHS Publ. 336, 2010, 264-269. (364 KB PDF)

Zhang, Y., Nearing, M.A., Wei, H. 2011. Effects of antecedent soil moisture on runoff modeling in small semiarid watersheds of southeastern Arizona. Hydrology and Earth System Sciences. 15, 3171–3179. (3.39 MB PDF)

Weltz, M.A., Jolley, L., Hernandez, M., Talbot, C., Nearing, M.A., Stone, J.J., Goodirch, D.C., Wei, H., Pierson Jr., F., Morris,C. 2011. National assessment of soil erosion on non-federal rangelands. J Soil Water Conservation 2011 66(5):154A-162A. (1.20 MB PDF)

Renard, K.G., Yoder, D.C., Lightle, D.T., Dabney, S.M. 2011. Universal Soil Loss Equation and Revised Universal Soil Loss Equation. Chap. 8 IN: Handbook of Erosion Modelling, Morgan, R.P.C. and Nearing, M. (Eds.), p. 137-167. Wiley-Blackwell, 401 p. (958 KB PDF)

Nunes, J.P., Nearing, M.A. 2011. Modelling Impacts of Climatic Change: Cast Studies using the New Generation of Erosion Models. Chap. 15 IN: Morgan, R.P. and M.A. Nearing (eds.). 2011. Handbook of Erosion Modelling. ISBN: 978-1- 051-9010-7 416 pgs. Wiley-Blackwell Publishers, Chichester, West Sussex, UK. pps. 289-312. (521 KB PDF)

Nearing, M.A., Hairsine, P.B. 2011. The Future of Soil Erosion Modelling. Ch. 20 In: Morgan, R.P. and M.A. Nearing (eds.). 2011. Handbook of Erosion Modelling. ISBN: 978-1- 051-9010-7. 416 pgs. Wiley-Blackwell Publishers, Chichester, West Sussex, UK. pps. 391-397. (742 KB PDF)

Fathelrahman, E.M., Ascough II, J.C., Hoag, D.L., Malone, R.W., Heilman, P., Wiles, L., Kanwar, R.S. 2011. Continum of risk analysis methods to assess tillage system sustainability at the experimental plot level. Sustainability. 3(7): 1035-1063 (5.16 MB PDF)

Fathelrahan, E.M., Ascough II, J.C., Hoag, D.L., Malone, R.W., Heilman, P., Wies, L., Kanwar, R.S. 2011. An economic and stochastic efficiency comparison of tillage systems in corn and soybean under risk. Experimental Agriculture. 47(1): 111-136. (1.25 MB PDF)

Delgado, J.A., Secchi, S., Groffman, P., Nearing, M.A., Goddard, T., Reicocky, D., Lal, R., Salon, P., Kitchen, N.R., Rice, C., Towery D. 2011. Conservation practices to mitigate and adapt to the effects of climate change. Journal of Soil and Water Conservation Soceity. 66(a): 118A-129A. (3.43 MB PDF)

Our full publication list is available at:

Future Science Events:

Click here for information about workshops, including an update on RHEM and the 9th Annual RISE Symposium at University of Arizona in October 2012.

Rainfall Report:

WGEW and SRER data can be downloaded from the web site at
Geographic locations of the three precipitation records can be found at


SWRC Scientists continue to win national awards and recognition, including PWA Scientist of the Year for David Goodrich and an OECD fellowship for Mark Nearing.  Click here for more information.

Staff News:    

Click here for SWRC news, including new hires, retirements, graduations, technology transfer and workshop reports.

SWRC Bulletin:

Contact the SWRC Research Leader, Dr. Phil Heilman at 520-647-9202 or  Mailing address is USDA ARS SWRC, 2000 E. Allen Rd., Tucson, AZ 85719 and web address is  The SWRC Bulletin is online at

SWRC Mission:

To develop knowledge and technology to conserve water and soil in semi-arid lands. 

Last Modified: 1/30/2012