Content uploaded by Joseph M. Wheaton
Author content
All content in this area was uploaded by Joseph M. Wheaton on Jul 01, 2019
Content may be subject to copyright.
A preview of the PDF is not available
Low-Tech Process-Based Restoration of Riverscapes: Design Manual. Version 1.0
Abstract
The purpose of this design manual is to provide restoration practitioners with guidelines for implementing a subset of low-tech tools —namely beaver dam analogues (BDAs) and post-assisted log structures (PALS)—for initiating process-based restoration in structurally-starved riverscapes. While the concept of process-based restoration in riverscapes has been advocated for at least two decades, details and specific examples on how to implement it remain sparse. Here, we describe ‘low-tech process-based restoration’ (LT-PBR) as a practice of using simple, low unit-cost, structural additions (e.g. wood and beaver dams) to riverscapes to mimic functions and initiate specific processes. Hallmarks of this approach include:
- An explicit focus on the processes that a low-tech restoration intervention is meant to promote
- A conscious effort to use cost-effective, low-tech treatments (e.g. hand-built, natural materials, non-engineered, short-term design life-spans) because of the need to efficiently scale-up application.
- ‘Letting the system do the work’ which defers critical decision making to riverscapes and nature’s ecosystem engineers.
Other resources available at: http://lowtechpbr.restoration.usu.edu
... Process-based protocols (e.g. Wheaton & MacFarlane 2014;Wheaton et al. 2019;Castro et al. 2023) have been widely implemented (e.g. Simmons & Vanderwal 2018;Smith 2023) and have made BDAs one of the fastest-growing approaches to stream restoration in the western United States (Goldfarb 2018). ...
... Initial monitoring of the project we report here documented inconsistent sediment dynamics behind different BDAs, high aggradation at the upstream structure, stable stream temperatures, elevated groundwater, and a small early growth and survival advantage to willow cuttings planted in the vicinity of BDAs (Orr et al. 2019). Most of these parameters were monitored over a few months to 2 years, which, although not inconsistent with the monitoring periods of other BDA projects (Table 1; table S3 in Pilliod et al. 2018), nevertheless merits further study to understand whether initial results predict long-term trajectories (Pollock et al. 2014;Wheaton et al. 2019). ...
... In contrast, beavers often build dams closely together in "complexes." Castro et al. (2017) and Wheaton et al. (2019) recommend building BDAs in complexes to enhance structure durability, although fewer than half of the published BDA projects we reviewed here built complexes. Our findings regarding durability and maintenance might have differed had our BDAs been built in complexes, but doing so would have reduced or eliminated experimental replication of willow copses. ...
Beaver-based restoration techniques seek to assist with the recovery of stream systems that have been damaged, degraded, or destroyed. In addition to reintroducing beaver, restoration practitioners have sought to mimic the influence of beaver dams on stream processes by building beaver dam analogs (BDAs). Stream restoration has been criticized for a lack of extended monitoring and a dearth of empirical evidence for the efficacy of BDAs. Here, we extend early and previously reported 1-to 2-year monitoring of five BDAs on a low-gradient stream lacking woody riparian vegetation to 3-6 years, depending on the parameter examined. BDAs raised groundwater near the stream and did not affect water temperatures during the duration of monitoring. Consistent with elevated groundwater levels, riparian willow cuttings grew 2.8-9.6 times more when planted near BDAs than far from BDAs, which was more than the 1.3-to 1.4-fold difference after the first growing season. In contrast, a short-term association between BDAs and willow survival disappeared in the long term. Likewise, sediment aggradation above the upstream BDA 1 year after construction reversed completely 4 years later, probably due to structural damage during high flows that could not be repaired until flows abated. Annual peak flow levels explained over 80% of the variation in the number of structures requiring annual repair. Our results suggest that BDA-based restoration should account for both the costs of structure maintenance during project planning and the importance of long-term monitoring during project assessment.
... Les riverscapes ou corridors fluviaux sont créés et maintenus par divers processus physiques et biologiques variant à diverses échelles spatiales et temporelles, créant ainsi des formes géomorphologiques et des communautés écologiques particulières, dépendantes des conditions locales (climat, géomorphologie,…) . Cette notion est donc intrinsèquement liée aux nouvelles approches multiscalaires décrites plus haut dans cette introduction (Glassic et al. 2024;Wheaton et al. 2019). 1.4 L'émergence et développement de la géomatique 1.4.1 Rôle de la géomatique dans le développement des nouvelles approches des corridors fluviaux Cependant, ce type d'approche a longtemps été difficilement applicable. ...
... Les castors contribuent également à l'accumulation de sédiments et à l'aggradation du cours d'eau par rupture de compétence. Ils jouent aussi un rôle d'épuration en diminuant les taux de nutriments (carbone, azote, phosphore,…) et de matière en suspension et de nutriments fins en sortie de complexe, tout en augmentant la production primaire via le stockage de ces nutriments,… (Kornse et Wohl 2020;Brazier et al. 2021;Wheaton et al. 2019). ...
Le Riverscapes Consortium est une collaboration internationale de chercheurs et de praticiens engagés dans la préservation du bon état de fonctionnement des corridors fluviaux. Pour ce faire, elle développe notamment, à l'Université d'Etat de l'Utah, des modèles dits de grade "production" à destination des gestionnaires. Ces modèles ont pour but de permettre la caractérisation des corridors fluviaux, ainsi que la priorisation des actions de restauration et de conservation. Ils utilisent pour ce faire des données géospatiales publiques, gratuites, et disponibles à l'échelle nationale.
Cependant, ces modèles ne sont pour l'heure quasiment qu'exclusivement appliqués sur le territoire étasunien. Ils sont automatisés dans le cloud pour les bassins versants américains et leurs résultats sont disponibles sur une plateforme dédiée, le "Data exchange". La faisabilité de l'application de ces modèles sur un contexte radicalement différent du contexte étasunien, tel que le contexte français, n'était pas connue avant le début de ce stage.
C'est dans ce contexte que s'inscrit le stage ayant donné naissance au présent document. L'objectif a donc été de tester la faisabilité d'une telle adaptation, via la création d'une base de données regroupant l'ensemble des couches de données géospatiales françaises utilisées et utilisables par les modèles, puis la modification de leurs scripts Python pour permettre leur fonctionnement avec les données françaises, la modification de certaines logiques des modèles, et la création de nouvelles symbologies et « Business Logics » (fichiers XML permettant l'affichage standardisé des résultats) françaises.
Au total, quatre des huit modèles de grade "production" ont été appliqués et modifiés pour fonctionner avec les données françaises, à savoir un modèle de contextualisation des couches utilisées (Riverscapes Context), un modèle estimant la largeur à plein bord du réseau hydrographique (Channel Area Tool), un modèle d'analyses topographiques (TauDEM), et un modèle permettant la caractérisation des unités géomorphologiques des corridors fluviaux et notamment du fond de vallée (VBET).
Ce projet appelle à être poursuivi. Des réflexions restent à mener sur la manière de adapter et d'appliquer les modèles suivants, et sur la pertinence même de l'application de certains d'entre eux (RCAT). A l'avenir, une calibration devra également être réalisée via télédétection et études de terrain, afin de permettre aux modèles de fournir des résultats exploitables sur le contexte français.
... A classic BDA consists of posts pounded into the channel bed and banks, with willow or other branches woven in among the posts ( fig. 4.20) (Wheaton et al. 2019). Beaver dam analogues are permeable, allowing water and some sediment to flow through them. ...
In Utah, and much of the Intermountain West, riparian forests make up a small percentage of the landscape but provide disproportionately large ecological functions and societal values. Since the early 1800s, Utah’s riparian forests have experienced shifts in natural disturbance regimes, changes in flow regimes and water tables, changes in vegetation composition and structure, introduction of exotic plant and animal species, and land use conversion. Today, managers need science-based guidance to assess ecological integrity, detect causes of degradation, and select appropriate methods for restoration of ecosystem processes and functions as well as the structure and composition of riparian forests. In this document, we provide a step-by-step process for making decisions about riparian forest restoration. These steps include (1) identification of forest vegetation types and hydrogeomorphic valley types, (2) identification of symptoms of degraded ecological integrity, (3) determination of stressors causing degradation, (4) selection of the appropriate management response(s) based on the symptoms and stressors present, and (5) selection of appropriate methods for collecting baseline data and monitoring management results. This process will assist managers in improving the ecological integrity and resilience in the face of current and future stressors.
... Riverscapes are created and maintained by different physical and biological processes that vary at different spatial and temporal scales, creating specific geomorphic forms and ecological communities that depend on local conditions (climate, geomorphology,…) ). This notion is therefore intrinsically linked to the new multiscalar approaches described earlier in this introduction (Glassic et al. 2024;Wheaton et al. 2019). ...
The Riverscapes Consortium is an international collaboration of researchers and practitioners dedicated to preserving the healthy functioning of riverscapes. To this end, it is developing "production" grade models for river managers, at Utah State University. The goal of these models is to characterize riverscapes and prioritize restoration and conservation efforts. To do this, they use free, public geospatial data available at a national scale.
However, these models are currently applied almost exclusively in the USA. They are automated in the cloud for American watersheds, and their results are available on a dedicated platform, the " Data Exchange ". The feasibility of applying these models to a context radically different from that of the USA, such as France, was not known before the start of this internship.
This was the context of the internship that produced the present document. The aim was, therefore, to test the feasibility of such an adaptation by creating a database containing all the French geodata layers used and usable by the models, then modifying their Python scripts to allow them to work with French data, modifying some of the models' logic, and creating new French symbologies and "business logics" (XML files allowing standardized presentation of results).
A total of four of the eight "production" grade models were applied and modified to work with French data, namely a model for contextualizing the layers used (Riverscapes Context), a model for estimating the full bankfull width of the riverscape network (Channel Area Tool), a model for topographic analysis (TauDEM), and a model for characterizing the geomorphological units of riverscapes and particularly valley bottoms (VBET).
This project needs to be continued. Further reflection is needed on how to adapt and apply the following models and on the relevance of applying some of them (RCAT). In the future, it will also be necessary to calibrate the models by means of remote sensing and field studies in order to obtain usable results in the French context.
... Addressing human alterations, including physical modifications, that restore diverse and functional ecosystems is essential for human well-being and to help river landscapes adapt to a changing climate (Science Task Force for the UN Decade on Ecosystem Restoration, 2021). Re-establishing natural riverine processes is considered one of the most effective restoration approaches to address physical modification (Beechie et al., 2010;Wheaton et al., 2019), whereby restoring natural geomorphic processes promotes habitat heterogeneity (Wohl et al., 2024), which in turn facilitates recovery following disturbances from extreme hydrological events (Chester & Robson, 2011;Dunbar et al., 2010;Townsend & Hildrew, 1994). ...
Physical habitat modification is one of the main pressures affecting river environments, impacting their ecosystem health and compromising their ability to adapt to the effects of climate change. Addressing the impacts of physical modification through reinvigorating natural processes has become a globally established river restoration technique. Here, we appraised such an approach by assessing ecological responses to a weir removal project on an English groundwater‐dominated ‘chalk’ stream. Using a Before‐After‐Control‐Impact (BACI) approach, we found that 3 years post‐restoration the macroinvertebrate communities are moving towards those of the target community both in terms of structural complexity (e.g., taxonomic composition) and functional integrity (e.g., trait composition). The progress is ongoing and has occurred alongside wider catchment improvements. Our results indicate that ecological responses to passive restoration undertaken on low energy streams, such as chalk streams, may be gradual, and thus longer‐term assessment is needed to fully appraise ecological recovery. We highlight the importance of a BACI approach to understand the local responses to restoration in a catchment context. Our findings also provide further evidence highlighting complementary ecological information provided by assessing taxonomic and functional properties concurrently in post‐project appraisals. A better understanding of ecological recovery times should be incorporated into future restoration planning. Such evidence would help develop robust assessments over appropriate timescales, increasing the likelihood of accurately and effectively appraising restoration project success, and helping to build support to increase the scale and pace of restoration actions needed to address biodiversity loss.
... Although abundant in-channel wood might not represent a historical precedent for restoration, enhancing habitat complexity with wood addition could initiate hydraulic and geomorphic processes that ultimately lead to diverse riverine geomorphology more representative of earlier conditions (e.g., Wheaton et al., 2019;Wohl et al., 2019). ...
Flow alteration and riparian vegetation encroachment are causing habitat simplification with severe consequences for native fishes. To assess the effectiveness of enhancing simplified habitat in a large dryland river, we experimentally added invasive wood at 19 paired treatment and reference (no wood added) subreaches (50–100 m) within the main channel of the San Juan River. Using a before-after-control-impact design, we sampled fishes and macroinvertebrates, and quantified habitat complexity. After wood addition, total native fish densities were 2.2× higher in treatments compared with references, whereas total nonnative fish densities exhibited no response. Macroinvertebrate densities were 6.8× higher, and habitat complexity increased in treatments. Counts of geomorphic features in treatments increased from 1 to a maximum of 11 following wood addition, while the number of features in references remained unchanged. Wood addition has potential to instigate natural riverine processes, ultimately enhancing native fish habitat by increasing macroinvertebrate densities and habitat complexity in dryland rivers. Water overallocation and increasing aridity will continue to challenge efforts to improve habitat conditions with environmental flows alone, and managers might consider integrating non-flow alternatives like addition of abundant, invasive wood to reduce habitat simplification.
In-stream wood jams alter their surrounding channel morphology, thus setting riverscape morphology and ecosystem function. While wood jams clearly scour pools, retain sediment, and influence bank erosion, there is a lack of observational evidence of how wood jam characteristics themselves control morphologic effects. Here, I analyzed field observations of hundreds of wood jams to test the hypothesis that wood jam characteristics can predict local morphologic effects such as sediment retention, bar forcing, and pool scour. I found mixed support for this hypothesis: While jam characteristics such as porosity, channel blockage ratio, thalweg occupation, and having rootwads and multiple trunks significantly predicted morphologic effect occurrence and magnitude, they only explained a small portion of the variance in those morphologic effects. While wood jam characteristics are relevant in controlling their overall morphologic functions, those functions are both inherently variable and likely affected by numerous other factors, such as reach-scale topography, the sediment transport capacity to supply ratio, and interactions with surrounding wood and vegetation. Wood function restoration may be more effective if it targets reach-scale objectives across dynamic wood jam assemblages, instead of individual jams.
Stream restoration is a proposed climate adaptation tool; however, outcomes of floodplain restoration on stream temperature have been debated. Despite a growing number of studies that investigated water temperature in restored streams, few have quantified temperature variations in new habitat types created by restored hydrogeomorphic processes to explore the effects on aquatic macroinvertebrates. We evaluated the hypotheses: (1) restoration increases habitat diversity, (2) habitat diversity increases water temperature variability, and (3) restoration increases the diversity of macroinvertebrate assemblage and temperature associations. In August 2021, we collected environmental data to describe the aquatic habitats, water temperature and quality (continuous and discrete), and macroinvertebrates in 40 riffle, pool, and off‐channel sites in a stream being restored, Whychus Creek, Oregon, USA. Our study is a site comparison of three reaches—one restored in 2012, another restored in 2016, and an unrestored (control) that will soon undergo restoration. Evaluations of the hypotheses show: (1) Habitat diversity in restored reaches is effectively three types of aquatic habitats versus only one in the control (riffles), (2) water temperature variability in habitats created by restoration (off‐channel) is high and low, and suggest a range of hyporheic connectivity and flow paths are present, and (3) restoration created a different macroinvertebrate assemblage, with 16 additional taxa in off‐channel habitats, and the range in macroinvertebrate thermal optima is approximately doubled when off‐channel macroinvertebrate thermal optima are accounted for. Our results support the idea that floodplain restoration creates more diverse thermal conditions and different macroinvertebrate communities in restored stream reaches.
The resilience of a river corridor represents its ability to withstand and recover from disturbances. Quantifying fluvial resilience in the face of various stressors is essential for integrating ecology and geomorphology in a context of river management. Geomorphic unit diversity analysis emerges as a valuable tool for characterizing and quantifying fluvial resilience to disturbances due to its inherent connection with fluvial dynamics. This paper aims to analyse and quantify the fluvial resilience of a wandering gravel-bed river affected by natural (e.g., floods) and human-induced (e.g., instream gravel mining) stressors. To achieve this goal, we use multi-temporal high-resolution topographic surveys of the Upper River Cinca (South-Central Pyrenees) spanning from 2014 to 2020. By employing the Geomorphic Unit Tool (GUT) on these surveys, we can map geomorphic units over time, quantify their diversity, and study geomorphic adjustments through morphodynamic signatures, altogether allowing inferring fluvial resilience.
Our findings reveal that topographic changes (i.e., erosion and sedimentation) correlate with the type of stressor: maintenance works and gravel mining lead to degradation, while floods induce aggradation. Geomorphic Unit Diversity decreases following channel disturbances caused by gravel mining but rebounds after periods primarily stressed by floods, returning to pre-impact levels within six years. Geomorphic adjustments, such as channel incision and mid bar development, reflect erosion and sedimentation processes respectively, with channel maintenance works and floods being the main drivers. Despite the recovery of the geomorphic unit diversity within the reach, the deficit resulting from gravel extraction remains unresolved, perpetuating a degrading trend that poses risks in reducing lateral connectivity and could potentially catalyse future vegetation encroachment in bars and floodplains, causing changes on flood conveyance and hydraulics. Monitoring the river's geomorphic diversity provides crucial insights for effective conservation and management decisions regarding land use, development, and conservation along riverbanks, thereby sustaining or enhancing fluvial system resilience.
The article explores future directions toward the conservation of the state of Arizona, aiming to preserve its multiple natural resources, including landscapes, wildlife, flora, unique ecosystems, and water resources. We evaluate the current governmental plans and laws focused on conservation, highlighting their impacts and identifying the existing gaps. Then, by analyzing such gaps, we uncover the main open conservation challenges within the state, such as urban expansion, climate change, water resource management, spreading of invasive species, and uranium mining and related activities, discussing their potential impact on future conservation efforts. Finally, the article introduces targeted strategies to enhance conservation outcomes, focusing on the importance of collaborative governance, innovative conservation technologies, multidisciplinary solutions, and law revisions. By adopting a forward-looking and multidisciplinary approach, we outline multiple prospective pathways for ensuring the long-term sustainability of Arizona’s natural resources, contributing to the wide global discussion on environmental conservation.
The Low-Tech Process Based Restoration of Riverscapes Pocket Guide is an illustrated and condensed version of the Design Manual (http://lowtechpbr.restoration.usu.edu). The pocket guide is designed to fit in your pocket (4 x 6") to use as a reference in the field.
Chapter Four of Low-Tech Process-Based Restoration of Riverscapes: Design Manual (http://lowtechpbr.restoration.usu.edu
Post-assisted log structures (PALS) and beaver dam analogues (BDAs) are hand-built structures. PALS mimicand promote the processes of wood accumulation; whereas BDAs mimic and promote beaver dam activity. •PALS and BDAs are permeable, temporary structures, built using natural materials. •BDAs differ from PALS in and that BDAs create ponds using a variety of fill materials; PALS are built with only woody material, which tends to be larger diameter than the woody material used for BDAs.•PALS and BDAs are both intended to address the broad impairment of structural starvation in wadeable streams, but can also be used to mitigate against a range of more specific impairments. •PALS and BDAs can be built using a variety of natural materials, and built to a range of different shapes, sizes and orientations.•PALS and BDAs are most likely to achieve restoration goals when built in high numbers.•Some PALS and BDAs are likely to breach and/or lose some wood, but when many structures are installed, that material will accumulate on downstream structures or in natural accumulation areas leading to more complexity.
Chapter Two of Low-Tech Process-Based Restoration of Riverscapes: Design Manual (http://lowtechpbr.restoration.usu.edu)
Low-tech process-based restoration principles are critical to understand as both the basis for effectively applying low-tech restoration treatments and managing expectations about timing and magnitude of outcomes.
We propose and synthesize principles that help practitioners tackle low-tech process-based restoration of structurally-starved riverscapes. Many of these principles likely apply to a greater range of riverscapes, but we do not cover those applications here.
We break our guiding principles into:
- Riverscapes Principles - those that represent an understanding of what constitutes healthy riverscapes to help define what restoration should be aiming for; and
- Restoration Principles – those that influence the choices and approach we take in planning, designing and implementing low-tech restoration.
Since we focus on structurally-starved riverscapes, low-tech restoration that mimics and promotes the processes of wood accumulation and beaver dam activity specifically emerge out of these principles.
These principles collectively provide practitioners with the rationale and strategies to attempt to tackle the true scope of degradation with simple, smart, agile and scalable low-tech solutions that rely on the system itself to do most of the work of recovery and find self-sustaining and resilient futures.
This report, contracted by the Utah Division of Wildlife Resources (UDWR) describes an Adaptive Management Plan for the translocation of beaver as part of stream restoration efforts in the Grouse Creek Watershed (bid AS17157; purchase order no. 560 170000000000222) in northwest Box Elder County, UT. The purpose of this report is to present an adaptive management plan that guides the translocation of beaver into restored stream reaches along Pine Creek, Kimbell Creek, and Cotton Creek in order to achieve restoration objectives and also mitigate the potential threats that such translocation may produce. The report provides a simple framework to guide decision making and management action as it pertains to beaver translocation, monitoring beaver activity, and potential management actions in response to threats to infrastructure posed by beaver dam building activity. The plan identifies specific courses of action in response to different levels of risk and beaver activity, but also acknowledges that ultimately management decisions belong to the private land-owner, Jay Tanner, for whom the restoration was performed. There are limited infrastructure concerns within the proposed translocation reaches, as such much of this report is concerned with outlining a more generalized approach to identifying potential risks outside of the restoration and translocation areas and presenting a decision-making framework.
Riparian and aquatic habitats support biodiversity and key environmental processes in semi-arid and arid landscapes, but stressors such as conventional livestock grazing, wildfire, and drought can degrade their condition. To enhance habitat for fish and wildlife and increase resiliency in these critical areas, land managers in the interior western United States increasingly use alternative grazing strategies, beaver management, or beaver dam surrogates as low-effort, low-expense restoration approaches. In this study we used historical archives of satellite and aerial imagery spanning three decades to characterize riparian vegetation productivity and document beaver dam occurrences, then evaluated vegetation productivity relative to land management associated with livestock grazing and beaver dam densities while accounting for climate and wildfire. After controlling for stream characteristics such as stream size, elevation, and stream slope, we demonstrate a positive response of riparian area vegetation to conservation-oriented grazing approaches and livestock exclosures, extensive beaver dam development, increased precipitation, and lack of wildfire. We show that livestock management which emphasizes riparian recovery objectives can be an important precursor to beaver activity and describe 11–39% increases in floodplain vegetation productivity where conservation-oriented grazing approaches or livestock exclosures and high beaver activity occur together on low-gradient sites. Land management decisions can therefore potentially confer resiliency to riparian areas under changing and variable climate conditions–the increased vegetation productivity resulting from conservation-oriented grazing or exclosures and high amounts of beaver activity at our sites is the equivalent to moving conventionally-grazed, low-gradient sites without beaver up at least 250 m in elevation or increasing water year precipitation by at least 250 mm.
Beaver reintroductions and beaver dam structures are an increasingly utilized ecological tool for rehabilitating degraded streams, yet beaver dams can potentially impact upstream fish migrations. We collected two years of data on Arctic grayling movement through a series of beaver dams in a low gradient mountain stream, utilizing radio‐telemetry techniques, to determine how hydrology, dam characteristics, and fish attributes impeded passage and movement rates of spawning grayling. We compared fish movement between a “normal” flow year and a “low” flow year, determined grayling passage probabilities over dams in relation to a suite of factors, and predicted daily movement rates in relation to the number of dams each fish passed and distance between dams during upstream migration to spawning areas. We found that the average passage probability over unbreached beaver dams was 88%, though we found that it fell below 50% at specific dams. Upstream passage of grayling was affected by three main characteristics: (a) temperature, (b) breach status, and (c) hydrologic linkages that connect sections of stream above and below the dam. Other variables influence passage, but to a lesser degree. Cumulative passage varied with distance upstream and total number of dams passed in low versus normal flow years, while movement rates upstream slowed as fish swam closer to dams. Our findings demonstrate that upstream passage of fish over beaver dams is strongly correlated with hydrologic conditions with moderate controls by dam‐ and fish‐level characteristics. Our results provide a framework that can be applied to reduce barrier effects when and where beaver dams pose a significant threat to the upstream migration of fish populations while maintaining the diverse ecological benefits of beaver activity when dams are not a threat to fish passage.
Stream restoration approaches most often quantify habitat degradation, and therefore recovery objectives, on aquatic habitat metrics based on a narrow range of species needs (e.g., salmon and trout), as well as channel evolution models and channel design tools biased toward single‐threaded, and “sediment‐balanced” channel patterns. Although this strategy enhances perceived habitat needs, it often fails to properly identify the underlying geomorphological and ecological processes limiting species recovery and ecosystem restoration. In this paper, a unique process‐based approach to restoration that strives to restore degraded stream, river, or meadow systems to the premanipulated condition is presented. The proposed relatively simple Geomorphic Grade Line (GGL) design method is based on Geographic Information System (GIS) and field‐based analyses and the development of design maps using relative elevation models that expose the relic predisturbance valley surface. Several case studies are presented to both describe the development of the GGL method and to illustrate how the GGL method of evaluating valley surfaces has been applied to Stage 0 restoration design. The paper also summarizes the wide applicability of the GGL method, the advantages and limitations of the method, and key considerations for future designers of Stage 0 systems anywhere in the world. By presenting this ongoing Stage 0 restoration work, the authors hope to inspire other practitioners to embrace the restoration of dynamism and diversity through restoring the processes that create multifaceted river systems that provide long‐term resiliency, meta‐stability, larger and more complex and diverse habitats, and optimal ecosystem benefits.
This was a talk expanding the classic river health analogy to think about what role restoration actions can play in contributing to a rivers health. The talk attempts to make the case for low-tech process based restoration as feeding meals to promote specific exercise (processes), as part of a healthy lifestyle for rivers. By contrast, most restoration practice is overly focused on surgery as the only restoration tool.
Restoration of riparian and wet meadow ecosystems in semi‐arid rangelands of the western U.S. is a high priority given their ecological and hydrological importance in the region. However, traditional restoration approaches are often intensive and costly, limiting the extent over which they can be applied. Practitioners are increasingly trying new restoration techniques that are more cost effective, less intensive, and can more practically scale up to the scope of degradation. Unfortunately, practitioners typically lack resources to undertake outcome‐based evaluations necessary to judge the efficacy of these techniques. In this study, we use freely‐available, satellite remote sensing to explore changes in vegetation productivity (NDVI) of three distinct, low‐tech riparian and wet meadow restoration projects. Case studies are presented that range in geographic location (Colorado, Oregon, and Nevada), restoration practice (Zeedyk structures, beaver dam analogs, and grazing management), and time since implementation. Restoration practices resulted in increased vegetation productivity of up to 25% and increased annual persistence of productive vegetation. Improvements in productivity with time since restoration suggest that elevated resilience may further enhance wildlife habitat and increase forage production. Long‐term, documented outcomes of conservation are rare; we hope our findings empower practitioners to further monitor and explore the use of low‐tech methods for restoration of ecohydrologic processes at meaningful spatial scales.
This article is protected by copyright. All rights reserved.
