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Since the late 1800s, pinyon–juniper woodland across the western U.S. has increased in density and areal extent and encroached into former grassland areas. The San Carlos Apache Tribe wants to gain qualitative and quantitative information on the historical conditions of their tribal woodlands to use as a baseline for restoration efforts. At the San Carlos Apache Reservation, in east-central Arizona, large swaths of woodlands containing varying mixtures of juniper (Juniperus spp.), pinyon (Pinus spp.) and evergreen oak (Quercus spp.) are culturally important to the Tribe and are a focus for restoration. To determine changes in canopy cover, we developed image analysis techniques to monitor tree and large shrub cover using 1935 and 2017 aerial imagery and compared results over the 82-year interval. Results showed a substantial increase in the canopy cover of the former savannas, and encroachment (mostly juniper) into the former grasslands of Big Prairie. The Tribe is currently engaged in converting juniper woodland back into an open savanna, more characteristic of assumed pre-reservation conditions for that area. Our analysis shows areas on Bee Flat that, under the Tribe’s active restoration efforts, have returned woodland canopy cover to levels roughly analogous to that measured in 1935.
Barry Middleton; Laura Norman. Remote Sensing Analysis to Quantify Change in Woodland Canopy Cover on the San Carlos Apache Reservation, Arizona, USA (1935 vs. 2017). Land 2021, 10, 393 .
AMA StyleBarry Middleton, Laura Norman. Remote Sensing Analysis to Quantify Change in Woodland Canopy Cover on the San Carlos Apache Reservation, Arizona, USA (1935 vs. 2017). Land. 2021; 10 (4):393.
Chicago/Turabian StyleBarry Middleton; Laura Norman. 2021. "Remote Sensing Analysis to Quantify Change in Woodland Canopy Cover on the San Carlos Apache Reservation, Arizona, USA (1935 vs. 2017)." Land 10, no. 4: 393.
The Sky Island Restoration Collaborative (SIRC) is a growing partnership between government agencies, nonprofit organizations, and private landowners in southeast Arizona, the United States, and northern Sonora, Mexico. Starting in 2014 as an experiment to cultivate restoration efforts by connecting people across vocations and nations, SIRC has evolved over 5 years into a flourishing landscape-restoration initiative. The group is founded on the concept of developing a restoration economy, where ecological and socioeconomic benefits are interconnected and complimentary. The variety of ideas, people, field sites, administration, and organizations promote learning and increase project success through iterative adaptive management, transparency, and sharing. The collaborative seeks to make restoration self-sustaining and improve quality of life for citizens living along the US-Mexico border. Research and experiments are developed between scientists and practitioners to test hypotheses, qualify procedures, and quantify impacts on shared projects. Simultaneously, partners encourage and facilitate connecting more people to the landscape—via volunteerism, internships, training, and mentoring. Through this history, SIRC’s evolution is pioneering the integration of community and ecological restoration to protect biodiversity in the Madrean Archipelago Ecoregion. This editorial introduces SIRC as a unique opportunity for scientists and practitioners looking to engage in binational partnerships and segues into this special journal issue we have assembled that relates new findings in the field of restoration ecology.
Laura M Norman; H Ronald Pulliam; Michele M Girard; Steve M Buckley; Louise Misztal; David Seibert; Carianne Campbell; James B Callegary; Deborah J Tosline; Natalie R Wilson; David Hodges; Jeffrey A Conn; A Valer Austin-Clark. Editorial: Combining the Science and Practice of Restoration Ecology—Case studies of a Grassroots Binational Restoration Collaborative in the Madrean Archipelago Ecoregion (2014-2019). Air, Soil and Water Research 2021, 14, 1 .
AMA StyleLaura M Norman, H Ronald Pulliam, Michele M Girard, Steve M Buckley, Louise Misztal, David Seibert, Carianne Campbell, James B Callegary, Deborah J Tosline, Natalie R Wilson, David Hodges, Jeffrey A Conn, A Valer Austin-Clark. Editorial: Combining the Science and Practice of Restoration Ecology—Case studies of a Grassroots Binational Restoration Collaborative in the Madrean Archipelago Ecoregion (2014-2019). Air, Soil and Water Research. 2021; 14 ():1.
Chicago/Turabian StyleLaura M Norman; H Ronald Pulliam; Michele M Girard; Steve M Buckley; Louise Misztal; David Seibert; Carianne Campbell; James B Callegary; Deborah J Tosline; Natalie R Wilson; David Hodges; Jeffrey A Conn; A Valer Austin-Clark. 2021. "Editorial: Combining the Science and Practice of Restoration Ecology—Case studies of a Grassroots Binational Restoration Collaborative in the Madrean Archipelago Ecoregion (2014-2019)." Air, Soil and Water Research 14, no. : 1.
The role of pyrogenic carbon (PyC) in the global carbon cycle is still incompletely characterized. Much work has been done to characterize PyC on landforms and in soils where it originates or in “terminal” reservoirs such as marine sediments. Less is known about intermediate reservoirs such as streams and rivers, and few studies have characterized hillslope and in-stream erosion control structures (ECS) designed to capture soils and sediments destabilized by wildfire. In this preliminary study, organic carbon (OC), total nitrogen (N), and stable isotope parameters, δ13C and δ15N, were compared to assess opportunities for carbon and nitrogen sequestration in postwildfire sediments (fluvents) deposited upgradient of ECS in ephemeral- and intermittent-stream channels. The variability of OC, N, δ13C, and δ15N were analyzed in conjunction with fire history, age of captured sediments, topographic position, and land cover. Comparison of samples in 2 watersheds indicates higher OC and N in ECS with more recently captured sediments located downstream of areas with higher burn severity. This is likely a consequence of (1) higher burn severity causing greater runoff, erosion, and transport of OC (organic matter) to ECS and (2) greater cumulative loss of OC and N in older sediments stored behind older ECS. In addition, C/N, δ13C, and δ15N results suggest that organic matter in sediments stored at older ECS are enriched in microbially processed biomass relative to those at newer ECS. We conservatively estimated the potential mean annual capture of OC by ECS, using values from the watershed with lower levels of OC, to be 3 to 4 metric tons, with a total potential storage of 293 to 368 metric tons in a watershed of 7.7 km2 and total area of 2000 ECS estimated at 2.6 ha (203-255 metric tons/ha). We extrapolated the OC results to the regional level (southwest USA) to estimate the potential for carbon sequestration using these practices. We estimated a potential of 0.01 Pg, which is significant in terms of ecosystem services and regional efforts to promote carbon storage.
James B Callegary; Laura M Norman; Christopher J Eastoe; Joel B Sankey; Ann Youberg. Preliminary Assessment of Carbon and Nitrogen Sequestration Potential of Wildfire-Derived Sediments Stored by Erosion Control Structures in Forest Ecosystems, Southwest USA. Air, Soil and Water Research 2021, 14, 1 .
AMA StyleJames B Callegary, Laura M Norman, Christopher J Eastoe, Joel B Sankey, Ann Youberg. Preliminary Assessment of Carbon and Nitrogen Sequestration Potential of Wildfire-Derived Sediments Stored by Erosion Control Structures in Forest Ecosystems, Southwest USA. Air, Soil and Water Research. 2021; 14 ():1.
Chicago/Turabian StyleJames B Callegary; Laura M Norman; Christopher J Eastoe; Joel B Sankey; Ann Youberg. 2021. "Preliminary Assessment of Carbon and Nitrogen Sequestration Potential of Wildfire-Derived Sediments Stored by Erosion Control Structures in Forest Ecosystems, Southwest USA." Air, Soil and Water Research 14, no. : 1.
Investment in conservation and ecological restoration depends on various socioeconomic factors and the social license for these activities. Our study demonstrates a method for targeting management of ecosystem services based on social values, identified by respondents through a collection of social survey data. We applied the Social Values for Ecosystem Services (SolVES) geographic information systems (GIS)-based tool in the Sonoita Creek watershed, Arizona, to map social values across the watershed. The survey focused on how respondents engage with the landscape, including through their ranking of 12 social values (eg, recreational, economic, or aesthetic value) and their placement of points on a map to identify their associations with the landscape. Additional information was elicited regarding how respondents engaged with water and various land uses, as well as their familiarity with restoration terminology. Results show how respondents perceive benefits from the natural environment. Specifically, maps of social values on the landscape show high social value along streamlines. Life-sustaining services, biological diversity, and aesthetics were the respondents’ highest rated social values. Land surrounding National Forest and private lands had lower values than conservation-based and state-owned areas, which we associate with landscape features. Results can inform watershed management by allowing managers to consider social values when prioritizing restoration or conservation investments.
Roy E Petrakis; Laura M Norman; Oliver Lysaght; Benson C Sherrouse; Darius Semmens; Kenneth J Bagstad; Richard Pritzlaff. Mapping Perceived Social Values to Support a Respondent-Defined Restoration Economy: Case Study in Southeastern Arizona, USA. Air, Soil and Water Research 2020, 13, 1 .
AMA StyleRoy E Petrakis, Laura M Norman, Oliver Lysaght, Benson C Sherrouse, Darius Semmens, Kenneth J Bagstad, Richard Pritzlaff. Mapping Perceived Social Values to Support a Respondent-Defined Restoration Economy: Case Study in Southeastern Arizona, USA. Air, Soil and Water Research. 2020; 13 ():1.
Chicago/Turabian StyleRoy E Petrakis; Laura M Norman; Oliver Lysaght; Benson C Sherrouse; Darius Semmens; Kenneth J Bagstad; Richard Pritzlaff. 2020. "Mapping Perceived Social Values to Support a Respondent-Defined Restoration Economy: Case Study in Southeastern Arizona, USA." Air, Soil and Water Research 13, no. : 1.
In northwestern Mexico and the southwestern United States, limited water supplies and fragile landscapes jeopardize world-renowned biological diversity. Simple rock detention structures have been used to manage agricultural water for over a thousand years and are now being installed to restore ecohydrological functionality but with little scientific evidence of their success. The impacts, design, and construction of such structures has been debated among local restoration practitioners, management, and permitting agencies. This article presents archeological documentation, local contentions, and examples of available research assessments of rock detention structures in the Madrean Archipelago Ecoregion. A US Geological Survey study to quantify impacts of rock detention structures using remote-sensing analyses, hydrologic monitoring, vegetation surveys, and watershed modeling is discussed, and results rendered in terms of the critical restoration ecosystem services provided. This framework provides a means for comparing management actions that might directly or indirectly impact human populations and assessing tradeoffs between them.
Laura M Norman. Ecosystem Services of Riparian Restoration: A Review of Rock Detention Structures in the Madrean Archipelago Ecoregion. Air, Soil and Water Research 2020, 13, 1 .
AMA StyleLaura M Norman. Ecosystem Services of Riparian Restoration: A Review of Rock Detention Structures in the Madrean Archipelago Ecoregion. Air, Soil and Water Research. 2020; 13 ():1.
Chicago/Turabian StyleLaura M Norman. 2020. "Ecosystem Services of Riparian Restoration: A Review of Rock Detention Structures in the Madrean Archipelago Ecoregion." Air, Soil and Water Research 13, no. : 1.
This paper describes how subdivision and development of rangelands within a remote and celebrated semi-arid watershed near the US–Mexico border might affect multiple ecohydrological services provided, such as recharge of the aquifer, water and sediment yield, water quality, flow rates and downstream cultural and natural resources. Specifically, we apply an uncalibrated watershed model and land-change forecasting scenario to consider the potential effects of converting rangelands to housing developments and document potential changes in hydrological ecosystem services. A new method to incorporate weather data in watershed modelling is introduced. Results of introducing residential development in this fragile arid environment portray changes in the water budget, including increases in surface-water runoff, water yield, and total sediment loading. Our findings also predict slight reductions in lateral soil water, a component of the water budget that is increasingly becoming recognized as critical to maintaining water availability in arid regions. We discuss how the proposed development on shrub/scrub rangelands could threaten to sever imperative ecohydrological interactions and impact multiple ecosystem services. This research highlights rangeland management issues important for the protection of open space, economic valuation of rangeland ecosystem services, conservation easements, and incentives to develop markets for these.
Laura M. Norman; Miguel Villarreal; Rewati Niraula; Mark Haberstich; Natalie R. Wilson. Modelling Development of Riparian Ranchlands Using Ecosystem Services at the Aravaipa Watershed, SE Arizona. Land 2019, 8, 64 .
AMA StyleLaura M. Norman, Miguel Villarreal, Rewati Niraula, Mark Haberstich, Natalie R. Wilson. Modelling Development of Riparian Ranchlands Using Ecosystem Services at the Aravaipa Watershed, SE Arizona. Land. 2019; 8 (4):64.
Chicago/Turabian StyleLaura M. Norman; Miguel Villarreal; Rewati Niraula; Mark Haberstich; Natalie R. Wilson. 2019. "Modelling Development of Riparian Ranchlands Using Ecosystem Services at the Aravaipa Watershed, SE Arizona." Land 8, no. 4: 64.
This paper describes coupling field experiments with surface and groundwater modeling to investigate rangelands of SE Arizona, USA using erosion-control structures to augment shallow and deep aquifer recharge. We collected field data to describe the physical and hydrological properties before and after gabions (caged riprap) were installed in an ephemeral channel. The modular finite-difference flow model is applied to simulate the amount of increase needed to raise groundwater levels. We used the average increase in infiltration measured in the field and projected on site, assuming all infiltration becomes recharge, to estimate how many gabions would be needed to increase recharge in the larger watershed. A watershed model was then applied and calibrated with discharge and 3D terrain measurements, to simulate flow volumes. Findings were coupled to extrapolate simulations and quantify long-term impacts of riparian restoration. Projected scenarios demonstrate how erosion-control structures could impact all components of the annual water budget. Results support the potential of watershed-wide gabion installation to increase total aquifer recharge, with models portraying increased subsurface connectivity and accentuated lateral flow contributions.
Laura M. Norman; James B. Callegary; Laurel Lacher; Natalie R. Wilson; Chloé Fandel; Brandon T. Forbes; Tyson Swetnam. Modeling Riparian Restoration Impacts on the Hydrologic Cycle at the Babacomari Ranch, SE Arizona, USA. Water 2019, 11, 381 .
AMA StyleLaura M. Norman, James B. Callegary, Laurel Lacher, Natalie R. Wilson, Chloé Fandel, Brandon T. Forbes, Tyson Swetnam. Modeling Riparian Restoration Impacts on the Hydrologic Cycle at the Babacomari Ranch, SE Arizona, USA. Water. 2019; 11 (2):381.
Chicago/Turabian StyleLaura M. Norman; James B. Callegary; Laurel Lacher; Natalie R. Wilson; Chloé Fandel; Brandon T. Forbes; Tyson Swetnam. 2019. "Modeling Riparian Restoration Impacts on the Hydrologic Cycle at the Babacomari Ranch, SE Arizona, USA." Water 11, no. 2: 381.
Mapping of vegetation types is of great importance to the San Carlos Apache Tribe and their management of forestry and fire fuels. Various remote sensing techniques were applied to classify multitemporal Landsat 8 satellite data, vegetation index, and digital elevation model data. A multitiered unsupervised classification generated over 900 classes that were then recoded to one of the 16 generalized vegetation/land cover classes using the Southwest Regional Gap Analysis Project (SWReGAP) map as a guide. A supervised classification was also run using field data collected in the SWReGAP project and our field campaign. Field data were gathered and accuracy assessments were generated to compare outputs. Our hypothesis was that a resulting map would update and potentially improve upon the vegetation/land cover class distributions of the older SWReGAP map over the 24,000 km2 study area. The estimated overall accuracies ranged between 43% and 75%, depending on which method and field dataset were used. The findings demonstrate the complexity of vegetation mapping, the importance of recent, high-quality-field data, and the potential for misleading results when insufficient field data are collected. Norman, Middleton, and Wilson: Remote sensing analysis of vegetation at the San Carlos Apache Reservation, Arizona and surrounding area1.IntroductionRemote sensing technology is often used to document and classify existing vegetation data at the regional scales.1 Vegetation/land cover maps can be developed either at a community level or species level by discerning spectral characteristics and translating them into classes.2 Large-scale projects are often constrained by the limited availability of high-resolution imagery and depend on lower resolution remotely sensed imagery as inputs that create lower resolution outputs.3 Accuracy can increase when newer products are used and when lower resolution data can be validated with field data.4 Gathering baseline conditions and change monitoring are advantages when creating good maps and improving the quality of the results.5A large mapping effort was undertaken to classify vegetation in the USA by the National Gap Analysis Program (GAP), where gap analysis was defined as a method for identifying “gaps” in conservation land and/or water locations.6 This was improved upon in the five southwestern states (Arizona, Colorado, New Mexico, Nevada, and Utah), by the Southwest Regional Gap Analysis Project (SWReGAP). SWReGAP provided land-cover mapping and assessment of biodiversity using Landsat ETM+ imagery (1999 to 2001) and digital elevation model (DEM) derivatives.7 The SWReGAP project used terrestrial ecological systems (TES) classification8 developed by NatureServe9 to emphasize dominant vegetation types.7,10,11 The SWReGAP map contains 125 land-cover classes with validation accuracy of 61%.7 This validation accuracy was based on an intermediate product, whereas the final, published map (based on all of the...
Laura M. Norman; Barry R. Middleton; Natalie R. Wilson. Remote sensing analysis of vegetation at the San Carlos Apache Reservation, Arizona and surrounding area. Journal of Applied Remote Sensing 2018, 12, 026017 .
AMA StyleLaura M. Norman, Barry R. Middleton, Natalie R. Wilson. Remote sensing analysis of vegetation at the San Carlos Apache Reservation, Arizona and surrounding area. Journal of Applied Remote Sensing. 2018; 12 (2):026017.
Chicago/Turabian StyleLaura M. Norman; Barry R. Middleton; Natalie R. Wilson. 2018. "Remote sensing analysis of vegetation at the San Carlos Apache Reservation, Arizona and surrounding area." Journal of Applied Remote Sensing 12, no. 2: 026017.
Urban and exurban expansion results in habitat and biodiversity loss globally. We hypothesize that a coupled-model approach could connect urban planning for future cities with landscape ecology to consider wildland habitat connectivity. Our work combines urban growth simulations with models of wildlife corridors to examine how species will be impacted by development to test this hypothesis. We leverage a land use change model (SLEUTH) with structural and functional landscape-connectivity modeling techniques to ascertain the spatial extent and locations of connectivity related threats to a national park in southern Arizona, USA, and describe how protected areas might be impacted by urban expansion. Results of projected growth significantly altered structural connectivity (80%) when compared to current (baseline) corridor conditions. Moreover, projected growth impacted functional connectivity differently amongst species, indicating resilience of some species and near-complete displacement of others. We propose that implementing a geospatial-design-based model will allow for a better understanding of the impacts management decisions have on wildlife populations. The application provides the potential to understand both human and environmental impacts of land-system dynamics, critical for long-term sustainability.
Ryan Perkl; Laura M. Norman; David Mitchell; Mark Feller; Garrett Smith; Natalie R. Wilson. Urban growth and landscape connectivity threats assessment at Saguaro National Park, Arizona, USA. Journal of Land Use Science 2018, 13, 102 -117.
AMA StyleRyan Perkl, Laura M. Norman, David Mitchell, Mark Feller, Garrett Smith, Natalie R. Wilson. Urban growth and landscape connectivity threats assessment at Saguaro National Park, Arizona, USA. Journal of Land Use Science. 2018; 13 (1-2):102-117.
Chicago/Turabian StyleRyan Perkl; Laura M. Norman; David Mitchell; Mark Feller; Garrett Smith; Natalie R. Wilson. 2018. "Urban growth and landscape connectivity threats assessment at Saguaro National Park, Arizona, USA." Journal of Land Use Science 13, no. 1-2: 102-117.
The practice of fire suppression across the western United States over the past century has led to dense forests, and when coupled with drought has contributed to an increase in large and destructive wildfires. Forest management efforts aimed at reducing flammable fuels through various fuel treatments can help to restore frequent fire regimes and increase forest resilience. Our research examines how different fuel treatments influenced burn severity and post-fire vegetative stand dynamics on the San Carlos Apache Reservation, in east-central Arizona, U.S.A. Our methods included the use of multitemporal remote sensing data and cloud computing to evaluate burn severity and post-fire vegetation conditions as well as statistical analyses. We investigated how forest thinning, commercial harvesting, prescribed burning, and resource benefit burning (managed wildfire) related to satellite measured burn severity (the difference Normalized Burn Ratio – dNBR) following the 2013 Creek Fire and used spectral measures of post-fire stand dynamics to track changes in land surface characteristics (i.e., brightness, greenness and wetness). We found strong negative relationships between dNBR and post-fire greenness and wetness, and a positive non-linear relationship between dNBR and brightness, with greater variability at higher severities. Fire severity and post-fire surface changes also differed by treatment type. Our results showed harvested and thinned sites that were not treated with prescribed fire had the highest severity fire. When harvesting was followed by a prescribed burn, the sites experienced lower burn severity and reduced post-fire changes in vegetation greenness and wetness. Areas that had previously experienced resource benefit burns had the lowest burn severities and the highest post-fire greenness measurements compared to all other treatments, except for where the prescribed burn had occurred. These results suggest that fire treatments may be most effective at reducing the probability of hazardous fire and increasing post-fire recovery. This research demonstrates the utility of remote sensing and spatial data to inform forest management, and how various fuel treatments can influence burn severity and post-fire vegetation response within ponderosa pine forests across the southwestern U.S.
Roy E. Petrakis; Miguel Villarreal; Zhuoting Wu; Robert Hetzler; Barry R. Middleton; Laura M. Norman. Evaluating and monitoring forest fuel treatments using remote sensing applications in Arizona, U.S.A. Forest Ecology and Management 2018, 413, 48 -61.
AMA StyleRoy E. Petrakis, Miguel Villarreal, Zhuoting Wu, Robert Hetzler, Barry R. Middleton, Laura M. Norman. Evaluating and monitoring forest fuel treatments using remote sensing applications in Arizona, U.S.A. Forest Ecology and Management. 2018; 413 ():48-61.
Chicago/Turabian StyleRoy E. Petrakis; Miguel Villarreal; Zhuoting Wu; Robert Hetzler; Barry R. Middleton; Laura M. Norman. 2018. "Evaluating and monitoring forest fuel treatments using remote sensing applications in Arizona, U.S.A." Forest Ecology and Management 413, no. : 48-61.
Natalie R. Wilson; Laura M. Norman. Analysis of vegetation recovery surrounding a restored wetland using the normalized difference infrared index (NDII) and normalized difference vegetation index (NDVI). International Journal of Remote Sensing 2018, 39, 3243 -3274.
AMA StyleNatalie R. Wilson, Laura M. Norman. Analysis of vegetation recovery surrounding a restored wetland using the normalized difference infrared index (NDII) and normalized difference vegetation index (NDVI). International Journal of Remote Sensing. 2018; 39 (10):3243-3274.
Chicago/Turabian StyleNatalie R. Wilson; Laura M. Norman. 2018. "Analysis of vegetation recovery surrounding a restored wetland using the normalized difference infrared index (NDII) and normalized difference vegetation index (NDVI)." International Journal of Remote Sensing 39, no. 10: 3243-3274.
The Western United States is expected to undergo both extended periods of drought and longer wildfire seasons under forecasted global climate change and it is important to understand how these disturbances will interact and affect recovery and composition of plant communities in the future. In this research paper we describe the temporal response of grassland communities to drought and fire in southern Arizona, where land managers are using repeated, prescribed fire as a habitat restoration tool. Using a 25-year atlas of fire locations, we paired sites with multiple fires to unburned control areas and compare satellite and field-based estimates of vegetation cover over time. Two hundred and fifty Landsat TM images, dating from 1985–2011, were used to derive estimates of Total Vegetation Fractional Cover (TVFC) of live and senescent grass using the Soil-Adjusted Total Vegetation Index (SATVI) and post-fire vegetation greenness using the Normalized Difference Vegetation Index (NDVI). We also implemented a Greenness to Cover Index that is the difference of time-standardized SATVI-TVFC and NDVI values at a given time and location to identify post-fire shifts in native, non-native, and annual plant cover. The results highlight anomalous greening and browning during drought periods related to amounts of annual and non-native plant cover present. Results suggest that aggressive application of prescribed fire may encourage spread of non-native perennial grasses and annual plants, particularly during droughts
Miguel L. Villarreal; Laura M. Norman; Steven Buckley; Cynthia S.A. Wallace; Michelle A. Coe. Multi-index time series monitoring of drought and fire effects on desert grasslands. Remote Sensing of Environment 2016, 183, 186 -197.
AMA StyleMiguel L. Villarreal, Laura M. Norman, Steven Buckley, Cynthia S.A. Wallace, Michelle A. Coe. Multi-index time series monitoring of drought and fire effects on desert grasslands. Remote Sensing of Environment. 2016; 183 ():186-197.
Chicago/Turabian StyleMiguel L. Villarreal; Laura M. Norman; Steven Buckley; Cynthia S.A. Wallace; Michelle A. Coe. 2016. "Multi-index time series monitoring of drought and fire effects on desert grasslands." Remote Sensing of Environment 183, no. : 186-197.
Natalie R. Wilson; Laura M. Norman; Miguel Villarreal; Leila Gass; Ron Tiller; Andrew Salywon. Comparison of remote sensing indices for monitoring of desert cienegas. Arid Land Research and Management 2016, 30, 460 -478.
AMA StyleNatalie R. Wilson, Laura M. Norman, Miguel Villarreal, Leila Gass, Ron Tiller, Andrew Salywon. Comparison of remote sensing indices for monitoring of desert cienegas. Arid Land Research and Management. 2016; 30 (4):460-478.
Chicago/Turabian StyleNatalie R. Wilson; Laura M. Norman; Miguel Villarreal; Leila Gass; Ron Tiller; Andrew Salywon. 2016. "Comparison of remote sensing indices for monitoring of desert cienegas." Arid Land Research and Management 30, no. 4: 460-478.
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. © 2015 The Authors. River Research and Applications published by John Wiley & Sons, Ltd.
Laura M Norman; F. Brinkerhoff; Evan Gwilliam; D. P. Guertin; James Callegary; David C Goodrich; Pamela L Nagler; F. Gray. Hydrologic Response of Streams Restored with Check Dams in the Chiricahua Mountains, Arizona. River Research and Applications 2015, 32, 519 -527.
AMA StyleLaura M Norman, F. Brinkerhoff, Evan Gwilliam, D. P. Guertin, James Callegary, David C Goodrich, Pamela L Nagler, F. Gray. Hydrologic Response of Streams Restored with Check Dams in the Chiricahua Mountains, Arizona. River Research and Applications. 2015; 32 (4):519-527.
Chicago/Turabian StyleLaura M Norman; F. Brinkerhoff; Evan Gwilliam; D. P. Guertin; James Callegary; David C Goodrich; Pamela L Nagler; F. Gray. 2015. "Hydrologic Response of Streams Restored with Check Dams in the Chiricahua Mountains, Arizona." River Research and Applications 32, no. 4: 519-527.
Rewati Niraula; Thomas Meixner; Laura M. Norman. Determining the importance of model calibration for forecasting absolute/relative changes in streamflow from LULC and climate changes. Journal of Hydrology 2015, 522, 439 -451.
AMA StyleRewati Niraula, Thomas Meixner, Laura M. Norman. Determining the importance of model calibration for forecasting absolute/relative changes in streamflow from LULC and climate changes. Journal of Hydrology. 2015; 522 ():439-451.
Chicago/Turabian StyleRewati Niraula; Thomas Meixner; Laura M. Norman. 2015. "Determining the importance of model calibration for forecasting absolute/relative changes in streamflow from LULC and climate changes." Journal of Hydrology 522, no. : 439-451.
Decades of intensive off‐road vehicle use for border security, immigration, smuggling, recreation, and military training along the USA–Mexico border have prompted concerns about long‐term human impacts on sensitive desert ecosystems. To help managers identify areas susceptible to soil erosion from anthropogenic activities, we developed a series of erosion potential models based on factors from the Universal Soil Loss Equation (USLE). To better express the vulnerability of soils to human disturbances, we refined two factors whose categorical and spatial representations limit the application of the USLE for non‐agricultural landscapes: the C‐factor (vegetation cover) and the P‐factor (support practice/management). A soil compaction index (P‐factor) was calculated as the difference in saturated hydrologic conductivity (Ks) between disturbed and undisturbed soils, which was then scaled up to maps of vehicle disturbances digitized from aerial photography. The C‐factor was improved using a satellite‐based vegetation index, which was better correlated with estimated ground cover (r2 = 0·77) than data derived from land cover (r2 = 0·06). We identified 9,780 km of unauthorized off‐road tracks in the 2,800‐km2 study area. Maps of these disturbances, when integrated with soil compaction data using the USLE, provided landscape‐scale information on areas vulnerable to erosion from both natural processes and human activities and are detailed enough for adaptive management and restoration planning. The models revealed erosion potential hotspots adjacent to the border and within areas managed as critical habitat for the threatened flat‐tailed horned lizard and endangered Sonoran pronghorn. Copyright © 2014 John Wiley & Sons, Ltd.
Miguel Villarreal; Robert H. Webb; Laura M. Norman; Jennifer L. Psillas; Abigail S. Rosenberg; Shinji Carmichael; Roy E. Petrakis; Philip E. Sparks. Modeling Landscape-scale Erosion Potential Related to Vehicle Disturbances Along the USA-Mexico Border. Land Degradation & Development 2014, 27, 1106 -1121.
AMA StyleMiguel Villarreal, Robert H. Webb, Laura M. Norman, Jennifer L. Psillas, Abigail S. Rosenberg, Shinji Carmichael, Roy E. Petrakis, Philip E. Sparks. Modeling Landscape-scale Erosion Potential Related to Vehicle Disturbances Along the USA-Mexico Border. Land Degradation & Development. 2014; 27 (4):1106-1121.
Chicago/Turabian StyleMiguel Villarreal; Robert H. Webb; Laura M. Norman; Jennifer L. Psillas; Abigail S. Rosenberg; Shinji Carmichael; Roy E. Petrakis; Philip E. Sparks. 2014. "Modeling Landscape-scale Erosion Potential Related to Vehicle Disturbances Along the USA-Mexico Border." Land Degradation & Development 27, no. 4: 1106-1121.
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
Laura Norman; Miguel Villarreal; H. Ronald Pulliam; Robert L. Minckley; Leila Gass; Cindy Tolle; Michelle Coe. Remote sensing analysis of riparian vegetation response to desert marsh restoration in the Mexican Highlands. Ecological Engineering 2014, 70, 241 -254.
AMA StyleLaura Norman, Miguel Villarreal, H. Ronald Pulliam, Robert L. Minckley, Leila Gass, Cindy Tolle, Michelle Coe. Remote sensing analysis of riparian vegetation response to desert marsh restoration in the Mexican Highlands. Ecological Engineering. 2014; 70 ():241-254.
Chicago/Turabian StyleLaura Norman; Miguel Villarreal; H. Ronald Pulliam; Robert L. Minckley; Leila Gass; Cindy Tolle; Michelle Coe. 2014. "Remote sensing analysis of riparian vegetation response to desert marsh restoration in the Mexican Highlands." Ecological Engineering 70, no. : 241-254.
In the Santa Cruz Watershed, located on the Arizona-Sonora portion of the U.S.-Mexico border, an international wastewater treatment plant treats wastewater from cities on both sides of the border, before discharging it into the river in Arizona. These artificial flows often subsidize important perennial surface water ecosystems in the region. An explicit understanding of the benefits of maintaining instream flow for present and future generations requires the ability to assess and understand the important trade-offs implicit in water-resource management decisions. In this paper, we outline an approach for modeling and visualizing impacts of management decisions in terms of rare terrestrial and aquatic wildlife, vegetation, surface water, groundwater recharge, real-estate values and socio-environmental vulnerable communities. We identify and quantify ecosystem services and model the potential reduction in effluent discharge to the U.S. that is under scrutiny by binational water policy makers and of concern to stakeholders. Results of service provisioning are presented, and implications for policy makers and resource managers are discussed. This paper presents a robust ecosystem services assessment of multiple scenarios of watershed management as a means to discern eco-hydrological responses and consider their potential values for future generations living in the borderlands.
Laura M. Norman; Miguel Villarreal; Rewati Niraula; Thomas Meixner; George Frisvold; William Labiosa. Framing Scenarios of Binational Water Policy with a Tool to Visualize, Quantify and Valuate Changes in Ecosystem Services. Water 2013, 5, 852 -874.
AMA StyleLaura M. Norman, Miguel Villarreal, Rewati Niraula, Thomas Meixner, George Frisvold, William Labiosa. Framing Scenarios of Binational Water Policy with a Tool to Visualize, Quantify and Valuate Changes in Ecosystem Services. Water. 2013; 5 (3):852-874.
Chicago/Turabian StyleLaura M. Norman; Miguel Villarreal; Rewati Niraula; Thomas Meixner; George Frisvold; William Labiosa. 2013. "Framing Scenarios of Binational Water Policy with a Tool to Visualize, Quantify and Valuate Changes in Ecosystem Services." Water 5, no. 3: 852-874.
Vegetation and land-cover changes are not always directional but follow complex trajectories over space and time, driven by changing anthropogenic and abiotic conditions. We present a multi-observational approach to land-change analysis that addresses the complex geographic and temporal variability of vegetation changes related to climate and land use. Using land-ownership data as a proxy for land-use practices, multitemporal land-cover maps, and repeat photography dating to the late 19th century, we examine changing spatial and temporal distributions of two vegetation types with high conservation value in the southwestern United States: grasslands and riparian vegetation. In contrast to many reported vegetation changes, notably shrub encroachment in desert grasslands, we found an overall increase in grassland area and decline of xeroriparian and riparian vegetation. These observed change patterns were neither temporally directional nor spatially uniform over the landscape. Historical data suggest that long-term vegetation changes coincide with broad climate fluctuations while fine-scale patterns are determined by land-management practices. In some cases, restoration and active management appear to weaken the effects of climate on vegetation; therefore, if land managers in this region act in accord with on-going directional changes, the current drought and associated ecological reorganization may provide an opportunity to achieve desired restoration endpoints.
Miguel L. Villarreal; Laura M. Norman; Robert H. Webb; Raymond M. Turner. Historical and Contemporary Geographic Data Reveal Complex Spatial and Temporal Responses of Vegetation to Climate and Land Stewardship. Land 2013, 2, 194 -224.
AMA StyleMiguel L. Villarreal, Laura M. Norman, Robert H. Webb, Raymond M. Turner. Historical and Contemporary Geographic Data Reveal Complex Spatial and Temporal Responses of Vegetation to Climate and Land Stewardship. Land. 2013; 2 (2):194-224.
Chicago/Turabian StyleMiguel L. Villarreal; Laura M. Norman; Robert H. Webb; Raymond M. Turner. 2013. "Historical and Contemporary Geographic Data Reveal Complex Spatial and Temporal Responses of Vegetation to Climate and Land Stewardship." Land 2, no. 2: 194-224.
Joan Fitzpatrick; Floyd Gray; Russell Dubiel; Jeff Langman; J. Bruce Moring; Laura M. Norman; William R. Page; Jean W. Parcher. The Borderlands and climate change: Chapter 10 in United States-Mexican Borderlands: Facing tomorrow's challenges through USGS science. Circular 2013, 235 -271.
AMA StyleJoan Fitzpatrick, Floyd Gray, Russell Dubiel, Jeff Langman, J. Bruce Moring, Laura M. Norman, William R. Page, Jean W. Parcher. The Borderlands and climate change: Chapter 10 in United States-Mexican Borderlands: Facing tomorrow's challenges through USGS science. Circular. 2013; ():235-271.
Chicago/Turabian StyleJoan Fitzpatrick; Floyd Gray; Russell Dubiel; Jeff Langman; J. Bruce Moring; Laura M. Norman; William R. Page; Jean W. Parcher. 2013. "The Borderlands and climate change: Chapter 10 in United States-Mexican Borderlands: Facing tomorrow's challenges through USGS science." Circular , no. : 235-271.