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"Discovery consists of seeing what everybody has seen and thinking what nobody had thought" – Albert Szent Gyorgyi 



Quantifying geomorphic change at ephemeral stream restoration sites using a coupled-model approach. Laura M. Norman, Joel B. Sankeyb, David Deanb, Joshua Casterb, Stephen DeLongc, Whitney DeLongd, Jon D. Pelletierd (2017)

Keywords : Restoration; Watershed models; 2D flow models; Terrestrial LiDAR

Abstract : Rock-detention structures are used as restoration treatments to engineer ephemeral stream channels of southeast Arizona, USA, to reduce streamflow velocity, limit erosion, retain sediment, and promote surface-water infiltration. Structures are intended to aggrade incised stream channels, yet little quantified evidence of efficacy is available. The goal of this 3-year study was to characterize the geomorphic impacts of rock-detention structures used as a restoration strategy and develop a methodology to predict the associated changes. We studied reaches of two ephemeral streams with different watershed management histories: one where thousands of loose-rock check dams were installed 30 years prior to our study, and one with structures constructed at the beginning of our study. The methods used included runoff, sediment transport, and geomorphic modelling and repeat terrestrial laser scanner (TLS) surveys to map landscape change. Where discharge data were not available, event-based runoff was estimated using KINEROS2, a one-dimensional kinematic-wave runoff and erosion model. Discharge measurements and estimates were used as input to a two-dimensional unsteady flow-and-sedimentation model (Nays2DH) that combined a gridded flow, transport, and bed and bank simulation with geomorphic change. Through comparison of consecutive DEMs, the potential to substitute uncalibrated models to analyze stream restoration is introduced. We demonstrate a new approach to assess hydraulics and associated patterns of aggradation and degradation resulting from the construction of check-dams and other transverse structures. Notably, we find that stream restoration using rock-detention structures is effective across vastly different timescales.


Hydrologic Response of Streams Restored with Check Dams in the Chiricahua Mountains, Arizona.  Norman, L. M., Brinkerhoff, F., Gwilliam, E., Guertin, D. P., Callegary, J., Goodrich, D. C., … Gray, F. (2015).

Abstract: In this study, hydrological processes are evaluated to determine impacts of stream restoration in the West Turkey Creek, Chiricahua Mountains, southeast Arizona, during a summer-monsoon season (June–October of 2013). A paired-watershed approach was used to analyze the effectiveness of check dams to mitigate high flows and impact long-term maintenance of hydrologic function. One watershed had been extensively altered by the installation of numerous small check dams over the past 30 years, and the other was untreated (control). We modified and installed a new stream-gauging mechanism developed for remote areas, to compare the water balance and calculate rainfall–runoff ratios. Results show that even 30 years after installation, most of the check dams were still functional. The watershed treated with check dams has a lower runoff response to precipitation compared with the untreated, most notably in measurements of peak flow. Concerns that downstream flows would be reduced in the treated watershed, due to storage of water behind upstream check dams, were not realized; instead, flow volumes were actually higher overall in the treated stream, even though peak flows were dampened. We surmise that check dams are a useful management tool for reducing flow velocities associated with erosion and degradation and posit they can increase baseflow in aridlands.


Model Analysis of Riparian Restoration Impacts on Long-Term Sediment and Water Budgets in Southeast Arizona, USA. Norman, L. M., & Niraula, R. (2015).

Abstract: The objective of this study was to evaluate the effect of check dam infrastructure on soil and water conservation at the catchment scale using the Soil and Water Assessment Tool (SWAT). This paired watershed study includes a watershed treated with over 2000 check dams and a Control watershed which has none, in the West Turkey Creek watershed, Southeast Arizona, USA. SWAT was calibrated for streamflow using discharge documented during the summer of 2013 at the Control site. Model results depict the necessity to eliminate lateral flow from SWAT models of aridland environments, the urgency to standardize geospatial soils data, and the care for which modelers must document altering parameters when presenting findings. Performance was assessed using the percent bias (PBIAS), with values of 2.34%. The calibrated model was then used to examine the impacts of check dams at the Treated watershed. Approximately 630 tons of sediment is estimated to be stored behind check dams in the Treated watershed over the 3-year simulation, increasing water quality for fish habitat. A minimum precipitation event of 15 mm was necessary to instigate the detachment of soil, sediments, or rock from the study area, which occurred 2% of the time. The resulting watershed model is useful as a predictive framework and decision support tool to consider long-term impacts of restoration and potential for future restoration.


Remote sensing analysis of riparian vegetation response to desert marsh restoration in the Mexican Highlands.Norman, L. M., Villarreal, M. L., Pulliam, H. R., Minckley, R., Gass, L., Tolle, C., & Coe, M. (2014). 

Keywords: Gabions; Cienega; Wetlands; Restoration; NDVI

Abstract: Desert marshes, or cienegas, are extremely biodiverse habitats imperiled by anthropogenic demands for water and changing climates. Given their widespread loss and increased recognition, remarkably little is known about restoration techniques. In this study, we examine the effects of gabions (wire baskets filled with rocks used as dams) on vegetation in the Cienega San Bernardino, in the Arizona, Sonora portion of the US-Mexico border, using a remote-sensing analysis coupled with field data. The Normalized Difference Vegetation Index (NDVI), used here as a proxy for plant biomass, is compared at gabion and control sites over a 27-year period during the driest months (May/June). Over this period, green-up occurred at most sites where there were gabions and at a few of the control sites where gabions had not been constructed. When we statistically controlled for differences among sites in source area, stream order, elevation, and interannual winter rainfall, as well as comparisons of before and after the initiation of gabion construction, vegetation increased around gabions yet did not change (or decreased) where there were no gabions. We found that NDVI does not vary with precipitation inputs prior to construction of gabions but demonstrates a strong response to precipitation after the gabions are built. Field data describing plant cover, species richness, and species composition document increases from 2000 to 2012 and corroborate reestablished biomass at gabions. Our findings validate that gabions can be used to restore riparian vegetation and potentially ameliorate drought conditions in a desert cienega.


Evaluating dryland ecological and river restoration using repeat LiDAR and hydrological monitoringHenderson, W. M.; DeLong, S. American Geophysical Union, Fall Meeting 2012

Abstract: Recent improvements in the collection of multitemporal, high-resolution topographic data such as Light Detection and Ranging (LiDAR) have done a great deal to increase our ability to quantify the details of landscape change. Both Terrestrial Laser Scanning (TLS) and Airborne Laser Swath Mapping (ALSM) can be used to easily assess how Earth surface processes affect landscape form to a level of precision that was previously more difficult to attain. A comprehensive approach using ALSM, TLS-TLS comparison, and hydrological monitoring is being used to assess the effectiveness of a large scale ecological and river restoration effort by the Cuenca los Ojos Foundation at San Bernardino Ranch near Agua Prieta, Sonora, Mexico. In the study area, historical arroyo cutting and changes in land use led to the abandonment of a ciénega wetland and resulted in widespread ecological destruction. The current land managers have employed engineering methods in order to restore stream and ciénega ecology, including the installation of large rock gabions, earthen berms, and concrete spillways along channels. Our goal is to test the hypothesis that the use of dam and gabion structures leads to stream aggradation, flash flood dampening, and ultimately, increased available water and reestablishment of historic wetland plant and animal communities. We present results from LiDAR change detection that includes 2007-2011 ALSM to TLS change, and several 2011-2012 TLS-TLS comparisons. We also present results from streamflow monitoring, field observation, and monitoring of shallow groundwater and soil moisture conditions. Preliminary results show that channel aggradation occurs rapidly upstream of engineered structures. However, the apparent dampening of sediment transport by the structures leads to less aggradation and even incision immediately downstream of structures. Peak flood flows are decreased by the reservoirs formed behind large earthen berms. After several years of water retention, both in surface reservoirs and in the alluvium deposited upstream of gabions and berms, plant growth recovers.



Evaluation of Arroyo Channel Restoration Efforts using Hydrological Modeling: Rancho San Bernardino, Sonora, MX. Jemison, N. E.; DeLong, S.; Henderson, W. M.; Adams, J. American Geophysical Union, Fall Meeting 2012

Abstract: In the drylands of the southwestern U.S. and northwestern Mexico, historical river channel incision (arroyo cutting) has led to the destruction of riparian ecological systems and cieñega wetlands in many locations. Along Silver Creek on the Arizona-Sonora border, the Cuenca Los Ojos Foundation has been installing rock gabions and concrete and earthen berms with a goal of slowing flash floods, raising groundwater levels, and refilling arroyo channels with sediment in an area that changed from a broad, perennially wet cieñega to a narrow sand- and gravel- dominated arroyo channel with an average depth of ~6 m. The engineering efforts hope to restore desert wetlands, regrow riparian vegetation, and promote sediment deposition along the arroyo floor. Hydrological modeling allows us to predict how rare flood events interact with the restoration efforts and may guide future approaches to dryland ecological restoration. This modeling is complemented by detailed topographic surveying and use of streamflow sensors to monitor hydrological processes in the restoration project. We evaluate the inundation associated with model 10-, 50-, 100-, 500-, and 1,000-year floods through the study area using FLO-2D and HEC-RAS modeling environments in order to evaluate the possibility of returning surface inundation to the former cieñega surface. According to HEC-RAS model predictions, given current channel configuration, it would require a 500-year flood to overtop the channel banks and reinundate the cieñega (now terrace) surface, though the 100-year flood may lead to limited terrace surface inundation. Based on our models, 10-year floods were ~2 m from overtopping the arroyo walls, 50-year floods came ~1.5 m from overtopping the arroyos, 100-year floods were ~1.2 m from overtopping, and 500- and 1,000-year floods at least partially inundated the cieñega surface. The current topography of Silver Creek does not allow for frequent flooding of the former cieñega; model predictions indicate that inundation would only occur in rare events with a ~500 year recurrence interval. In addition, by updating modeling as restoration efforts change the stream bed depth and valley geometry, we can quantify the effects of the restoration effort on surface hydrology. Local bed aggradation upstream of gabion and dam structures occurs in smaller floods, and if carefully planned and managed, could lead to wider flood inundation as the channel is able to reintegrate with the former floodplain.



Isotopic analysis of wetland development in the American Southwest. Thomas A. Minckley, Mark T. Clementz, Andrea Brunelle and Grace A. Klopfenstein (2009)

Keywords: Ciénegas, wetland development, Chihuahuan Desert, isotopes, climate change, sedimentation, Sonoran Desert, late Holocene.

Abstract: The analysis of stable isotope and elemental fractions of organic material collected from San Bernardino Ciénega was used to understand the history of vegetation composition and climate change within this desert wetland. A 4000-yr record of sediment buildup, based on four 14C measurements, provides unique opportunities for the study of environmental conditions within an arid landscape and documents climate shifts from drier to wetter conditions in the late Holocene. δ13C, δ15N, and C:N values were measured from a 3.8 m deep sedimentary section to understand the dynamics of vegetation and hydrology in desert wetlands. Through this section we observe δ13C and C:N values indicating a shift in the dominant source of organic matter within the section: prior to 850 cal. yr BP (below 60 cm), aquatic vascular plants and occasionally terrestrial vegetation were the primary organic sources, whereas freshwater algae were the dominant organic matter source above this level. These values indicate that while conditions remained arid at this locality, the amount of standing water on the ciénega has increased over time. These results document both climate change and vegetation evolution on the ecotone of the Sonoran and Chihuahuan deserts and demonstrate how the study of local sediment accumulation in ciénegas can provide critical information on changing conditions within arid environments.

  • Fluvial field research centered around the effects of channel modifications on flow conditions and sedimentation rates. Tom Elliot, University of Guelph, Canada.
  • Comprehensive field natural history study of the middle portion of the Cajon Bonito watershed. Robert Hunt, Prescott College.
  • Restoration and dynamics of riparian communities in the San Bernardino Valley, Sonora, Mexico, and Sonora Arizona. Baruk Maldonado and Noelia de la Torre, Centro de Estudios Superiores del Estado de Sonora.






  • Comparison of Montane snakes in burned and unburned Madrean Woodlands. Gary Belovsky and Kirk Stetser, University of Notre Dame.
  • Developmental biology of the Sonoran Mud Turtle (Kinosternon sonoriense). Melissa Cameron
  • Grey fox food habits and habitat association at El Pinito, Sonora. Betzade Duenas, Universidad Nacional Autonoma de Mexico.
  • Study of the ridgenose rattlesnake. Matt Goode, herpetologist.
  • Differences in population structure of Desert Box Turtles (Terrapene ornata luteola) related to proximity to roads. David Hall
  • Effects of fire on the Chihuahuan desert ant communities. Edward Lebrun, University of Utah.
  • Structure of the mammal community at Sierra San Luis: abundance, species, richness and diversity. Carlos Lopez Gonzalez, Universidad Autonoma de Queretaro.
  • Bee diversity and population dynamics in desert ecosystems: the role of seasonality. Robert Minckley, University of Rochester.
  • Standardized monitoring protocols for pollinator assessment. Robert Minckley, University of Rochester, with Gretchen Lebuhn.
  • Evolution of generalized pollination interactions in specialist pollinator communities. Robert Minckley, University of Rochester, with T’ai Roulston.
  • Beaver population study. Juan Pablo Gall-Reynoso, Laboratorio de Ecofisiologia, Centro de Investigacion en Alimentacion y Desarrollo.
  • Thermal biology and activities of the Ornate box turtle in Southeastern Arizona. Michael Plummer, Harding University.
  • Recovery of a previously-studied high elevation population of the Bunch Grass Lizard(Sceloporus scalaris). Anna Pock, Justin Congdon, Richard C. van Loben Sels, and Royce Ballinger.
  • Habitat use by Black bear at El Pinito. Ivan Sayago Vasquez, Universidad Nacional Autonoma de Mexico.
  • Black bear food habits at El Pinito. Varmen Silva Hurtado, Universidad Nacional Autonoma de Mexico.
  • Interaction between ant genus Pheidole and its many specialist parasitoids of the fly genus Apocephalus. Elliot Wilkinson, University of Utah.
  • Can vertebrae predation alter aggregation of risk in an insect host-parasitoid system? – Journal of Animal Ecology • 71: pp • 487-496 • Fagan, William F. 2002.

  • Ecology, life history and demography of the Sonoran Mud Turtle (Kinosternon sonoriense) – Hollett, W.P. 2002 • MS Thesis • 164 pp (University of Guelph, Guelph, Ontario, Canada).

  • Activity and Thermal Ecology of the Box Turtle (Terrapene ornata) at its Southwestern Range Limit in Arizona. Chelonian Conservation and Biology. – Plummer, Michael V. 2003 • 4: pp • 569-577

  • Effects of Dehydration on the Critical Thermal Maximum of the Desert Box Turtle (Terrapene ornata luteola) – Plummer, M.V., B.K. Williams, M.M. Skiver, and J.C. Carlyle • 2003 • Journal of Herpetology • 37:4 pp • 747-750

  • Thick-billed Parrot Releases in Arizona. The Condor. – Snyder, Noel F.R. and Susan E. Koenig, James Koschmann, Helen A. Snyder, Terry B. Johnson • 1994 • 96: pp • 845-862

  • Life history and ecology of the Sonoran mud turtle (Kinosternon sonoriense) in southeast Arizona: a preliminary report. – van Loben Sels, R.C., J.D. Congdon, and J.T. Austin. 1997 • Chelonian Conservation and Biology. 2: pp • 338-344

  • Spatial ecology and population structure of endangered black bears (Ursus americanus). Northwestern Mexico.Rodriguez Martinez, A., Claudia N. Moreno Arzate, E. Rubi González Sierra y Carlos A. López González. 2007. Proceedings of the Western Black Bear Workshop 9: 8-19.

  • Sexual differentiation in the distribution potential of northern jaguars (Panthera onca).Boydston, E. E. y C. A. López González, C. A. 2005. Pp. 51-56. In: Connecting mountain islands and desert seas: biodiversity and management of the Madrean Archipelago II. 2004 May 11-15; Tucson, AZ. Proceedings RMRS-P-36. G. J. Gottfried, B. S. Gebow, L. G. Eskew & C. Edminster (eds.). U. S. Forest Service. Fort Collins, CO: US Department of Agriculture, Forest Service, Rocky Mountain Research Station.

  • Abundance and food habits of cougars and bobcats in the Sierra San Luis, Sonora. Luna Soria, H. y C. A. López González. 2005. Pp. 416-420. In: Connecting mountain islands and desert seas: biodiversity and management of the Madrean Archipelago II. 2004 May 11-15; Tucson, AZ. Proceedings RMRS-P-36. G. J. Gottfried, B. S. Gebow, L. G. Eskew & C. Edminster (eds.). U. S. Forest Service. Fort Collins, CO: US Department of Agriculture, Forest Service, Rocky Mountain Research Station.

  • Habitat and conservation status of the beaver (Castor Canadensis) in the Sierra San Luis, Sonora. Pelz Serrano, K., E. Ponce Guevara y C. A. López González. 2005. Pp. 429-433. In: Connecting mountain islands and desert seas: biodiversity and management of the Madrean Archipelago II. 2004 May 11-15; Tucson, AZ. Proceedings RMRS-P-36. G. J. Gottfried, B. S. Gebow, L. G. Eskew & C. Edminster (eds.). U. S. Forest Service. Fort Collins, CO: US Department of Agriculture, Forest Service, Rocky Mountain Research Station.




  • Plant succession rates and trajectories in mesic and xeric desert habitats in the San Bernardino Valley, Sonora, Mexico and Sonora, Arizona. Robert Minckley, University of Rochester.
  • Germination and dispersal of seeds and fruits of Proboscidea parviflora in San Bernardino Valley, Sonora, Mexico and Sonora, Arizona. Jose Arturo Romero Gutierrez, Centro de Estudios Superiores del Estado de Sonora.
  • Buffel grass mapping. Tom Van Devender, Mark Dimmitt, Ana Lilia Reina







  • Tamaño poblacional del oso negro (Ursus americanus) en dos Islas del Cielo del Noreste de Sonora, México. Eugenia Espinosa-Flores, Nalleli E. Lara-Díaz y Carlos A. López-González. 2012. Therya 3(3): 403-416.
  • El oso negro americano en el noroeste de México: recuperación de registros de ocurrencia.Delfin Alfonso, Christian A.; Lopez Gonzalez, Carlos A. y Nalleli Lara-Diaz. 2011. Acta Zoologica Mexicana 27(3):777-801.
  • Abundancia y densidad de venado cola blanca (Odocoileus virginianus couesi) en Sierra de San Luis, Sonora, México. Nalleli E. Lara Díaz, Helí Coronel Arellano, Alejandro González Bernal, Carmina Gutiérrez González y Carlos Alberto López González. 2011. Therya 2(2)
  • ¿Pueden las variables de paisaje predecir la abundancia de venado cola blanca? El caso del noroeste de México. Helí Coronel Arellano, Carlos A. López González, y Claudia N. Moreno Arzate. 2009.  Tropical Conservation Science 2(2):229-236. ISSN 1940-0829
  • Ampliacion del Area Geografica de Distribucion de la Culebra de Agua de Cabeza Angosta Thamnophis rufipunctatus en el Estado de Sonora, Mexico. Alberto González Romero, Carlos A. López González, Mircea G. Hidalgo Mihart y Lisette Cantu Salazar. 2002. Boletin de la Sociedad Herpetologica Mexicana 10: 51.
  • Borderland jaguars: Tigres de la Frontera. David E. Brown y C. A. López González. 2001. University of Utah Press. 170 pp. ISBN 087-480-696-8.
  • Conservación de mamíferos depredadores en el norte de México. Carlos A. López González. 2008. In: Memorias de la segunda reunión cátedra nacional de biología 2008 “Juan Luis Cifuentes Lemus” Temática: Biología de la Conservación “Ecología”. I. E. Castellanos Sturemark, C. E. Moreno Ortega, R. Ortiz Pulido, N. Pompilio Pavón Hernández, A. Ramírez Bautista, A. E. Rojas Martínez, G. Sánchez Rojas, I. L. Zuria Jordán (Comp.). Universidad Autonoma del Estado de Hidalgo.
  • Uso de hábitat, hábitos alimenticios y estructura poblacional del oso negro (Ursus americanus) en la Sierra Madre Occidental” A. Rodríguez Martinez, C. N. Moreno Arzate, R. González Sierra y C. A. López González. 2008. . C. Lorenzo y E. Espinoza (eds.) Avances en el Estudio de los Mamiferos de Mexico II. Asociación Mexicana de Mastozoologia A. C.
  • Los osos negros frenados por la frontera. Varas, C., C. A. López González y M. Culver. 2007. In: Ana Córdova y Carlos de la Parra (coord). Una barrera a nuestro ambiente compartido: El muro fronterizo entre México y Estados Unidos. COLEF-SEMARNAT-INE. ISBN  968-794-762-4.  . 216 pp.
  • Distribución y estado de conservación actuales del jaguar en el noroeste de Mexico.López González, C. A. y D. E. Brown. 2002.  Pp. 379-391. In: Medellin, R. A., C. Equihua, C. L. B. Chetkiewicz, P. G. Crawshaw, A. Rabinowitz, K. H. Redford, J. G. Robinson, E. Sanderson, and A. Taber (comp.). El jaguar en el nuevo milenio. Fondo de Cultura Economica-Universidad Nacional Autonoma de Mexico –Wildlife Conservation Society.
  • Presencia de fibromas en el género Odocoileus en el Estado de Sonora, México.Daniel Ávila Aguilar, Nalleli E. Lara Diaz y Carlos A. López González. 2012. XIII Simposio sobre Venados de Mexico. 23 al 25 de Mayo de 2012.
  • Cougar (Puma concolor) population status, and biological corridors in Sierra San Luis, Sonora México. Alejandro González-Bernal, Nalleli E. Lara-Díaz, Heli Coronel-Arellano y Carlos A. López-González. 2011. Proceedings of the 10th Mountain Lion Workshop, Bozeman MT. Western Association of fish and Wildlife Agencies. 
  • Abundancia y densidad poblacional de oso negro (Ursus americanus) en el noreste de Sonora, México: Resultados preliminares.Nalleli E. Lara Díaz, Alejandro González Bernal, Helí Coronel Arellano, Rosa Elena Jiménez Maldonado, Eugenia Espinosa Flores, Gerardo Carreón Arroyo y Carlos Alberto López González. 2009.  XXVI Simposio sobre Fauna Silvestre “Gral. MV. Manuel Cabrera Valtierra”. 21 al 23 de octubre de 2009.
  • Estimando la densidad de mamíferos (medianos y grandes) utilizando trampas cámara: caso de estudio con cérvidos. XXVI Simposio sobre Fauna Silvestre. Lara Díaz, N. E., H. Coronel Arellano, A. González Bernal, C. Gutiérrez González y Carlos Alberto López González. 2009.Gral. MV. Manuel Cabrera Valtierra”. 21 al 23 de octubre de 2009.
  • Densidad y biomasa de mamíferos silvestres medianos y grandes en la Sierra de San Luis, Sonora, México. Nalleli E. Lara Diaz, Heli Coronel Arellano y Carlos A. López González. 2008. Memorias del XXV Simposio Sobre Fauna Silvestre “Gral. MV. Manuel Cabrera Valtierra”. 22 al 24 de octubre de 2008.
  • Patrones de actividad y asociación de hábitat de los mamíferos medianos y grandes en la Sierra de San Luis, Sonora, México. Ivan A. Sáyago Vázquez, Ma. del Carmen Silva Hurtado, E. Betzabe Dueñas Bustos y Carlos A. López González. 2003. Pp. 100-105. In: XX Simposio sobre fauna silvestre Gral. MV Manuel Cabrera Valtierra. 26-28 Nov, 2003.
  • Habitos alimenticios de la zorra gris (Urocyon cinereoargenteus) en la Sierra de San Luis, Sonora, Mexico. Dueñas Bustos, B. y Carlos A. López González. 2003. Pp. 121-126. In: XX Simposio sobre fauna silvestre Gral. MV Manuel Cabrera Valtierra. 26-28 Noviembre 2003.