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Escherichia coli are fecal indicator bacteria that reach waterbodies through aging and failing infrastructure in cities. Exposure to pathogens in untreated sewage can result in gastrointestinal disease, which frequently goes unreported. In the United States, the Clean Water Act regulates point source discharges of sewage and treated wastewater, but fecal indicator bacteria remain the second leading cause of river impairment. The burden of this contamination is not equitably distributed, with Black, Indigenous, and communities of color suffering from a disproportionate burden of untreated and overflowing waste and subsequent health impacts. Regulatory failures, and even abandonment, along with the exclusion of people of color from the mainstream environmental movement, mean that new approaches are needed to help communities empower themselves to address contamination. Community‐led groups that engage residents in addressing issues within and beyond regulatory frameworks have used approaches including trash traps, riparian planting and restoration, and community‐led monitoring. Mycofiltration, or the use of fungi to filter pollutants from water, is an emerging and understudied method of remediating E. coli. The low cost of mycofilter installation and maintenance may give agency to communities that have been unduly burdened with sewage contamination to diminish harmful exposures in the near term, even as they continue working toward longer‐term regulatory fixes. Continued research is needed to fully understand how different species of mycelium work under varying hydrologic conditions, including in‐field installations, along with long‐term monitoring and community acceptance to understand the efficacy and the potential impact of this strategy. [ABSTRACT FROM AUTHOR]

We evaluated the effects of riparian forests restoration on anuran communities in the Brazilian Cerrado. We analyzed five riparian reforested fragments around a reservoir of an hydroelectric plant using microhabitat variables (humidity, canopy opening, amount of leaf litter and vegetation density), the dominant landscape (matrix type, fragment width) and reforestation age. We tested whether anuran abundance, richness and diversity were influenced by these variables using generalized linear models. Matrix type and fragment width were limiting factors for anurans to reach and establish themselves in riparian forest fragments, whereas microhabitat and reforestation age did not influence anuran succession. We conclude that reforestation in the midst of impermeable matrices creates anuran communities dominated by widely-distributed species that live in open areas, reflecting the highly modified surrounding habitat. [ABSTRACT FROM AUTHOR]

A successful restoration of riparian forests can recover the diversity of several groups of soil invertebrates. However, few studies have considered the recovery of the entire community of soil macrofauna and the relative effect in taxonomical and functional diversity. We evaluated how taxonomical diversity, in terms of abundance and richness, relates to trophic diversity in four patches of riparian forests that had been artificially recovered, and compared them to the reference site in Volta Grande Reservoir, Brazil. No relationship was found between taxonomic diversity and trophic diversity, suggesting functional redundancy among taxonomic groups. Nevertheless, we observed that the taxonomic group with more species presented higher trophic diversity than the rest, indicating low functional redundancy within this group. The abundance and the taxonomic and functional richness of the four restored sites was similar to the reference site. The forest recovery was efficient in recovering invertebrate soil community since the taxonomic and trophic composition recorded in our studywere similar to the composition of natural areas. We emphasize the importance of studying edaphic fauna as a community in order to comprehend how it reacts to forest restoration. [ABSTRACT FROM AUTHOR]

The targeted removal of a non-native species can result in secondary invasions and other unexpected shifts in plant community composition, but the persistence of these effects is less well known. We investigated how the plant community changed at three time points including before removal (pre-removal), in the years directly following removal (post-removal), and 16 years following Tamarix removal (recent) in an arid depressional wetland. Non-native species cover increased and several non-native species invaded the study area in the years between post-removal surveys and the recent time period, suggesting Tamarix removal may have been a catalyst for increases in non-native species abundance. We also found an increase in the cover of species tolerating upland conditions, and these species were largely non-native. Overall, interactions between targeted removal and shifts in the abiotic environment due to climate change are important drivers of persistent shifts in the plant community. Hydrogeomorphic restoration is likely needed in tandem with invasive removal to see improvements in riparian health, particularly when the invasive species to be removed is a passenger in addition to being a driver of change. • Non-native species increased after Tamarix removal indicating secondary invasions. • Upland-tolerant species increased after Tamarix removal indicating continued drying. • Important to restore function alongside invasive species management. [ABSTRACT FROM AUTHOR]

Natural rivers offer riparian habitats to many highly specialised, rare, and endangered insect species and are extremely important for ecosystem services. In the past, these ecosystems have been heavily degraded by anthropogenic use and run the risk of losing their favourable ecological conditions. For this reason, restoration measures are urgently needed and strongly demanded politically as well as legally, for instance, through the European Union Water Framework Directive. This is also important because nowadays, we are confronted with increasing insect declines. Using a Before‐After‐Control‐Impact approach, we studied the effects of a riverbank restoration (complete removal of a large gravel embankment) on carabid assemblages of riparian habitats along the Mulde River in central Germany in 2017 and 2019. We collected 86 species in three site types (managed, natural, and restored) by pitfall trapping and found numerous species of conservation concern. Our analyses showed that the percentage of species of conservation concern was significantly higher after restoration in restored compared to managed sites. Furthermore, after restoration, the percentage of indicator species for natural sites increased significantly in restored sites while the abundance of indicator species characteristic for managed sites decreased in these sites. Species assemblage composition significantly changed in response to restoration approaching near‐natural conditions. The creation of habitat mosaics with open gravel and sand patches as well as the re‐establishment of river dynamics were likely the most significant drivers for restoration success. We were able to show how important the restoration of riparian habitats is to promote populations of endangered, rare, and specialised species. Our results highlight that positive effects of a river restoration measure can be observed after a relatively short time. Ground beetles can thus be viewed as early indicators for restoration success, but we see a need for long‐term monitoring to evaluate long‐term effects reliably. [ABSTRACT FROM AUTHOR]

With evidence of pollinator declines and an increasing focus on restoration, interest is growing in investigating floral resources for native bees. Although native bees forage on shrubs, few studies have explored the pollinator communities of native shrubs and none have examined shrub‐pollinator interactions in riparian areas of the northwestern United States. Life history traits of shrubs may make them particularly important resources for bees, especially in early spring—a key point in the lifecycle of many bee species. We conducted extensive hand‐net surveys over 2 years in a large riparian restoration project in the Pacific Northwest to understand bee‐flowering plant interactions with the aim of guiding future restoration efforts. Although forb blooming stem abundance and richness were higher than that of shrubs in spring, 57% of bees observed foraging were on willow (Salix spp.), a commonly planted riparian shrub. Season‐long, bee community composition on shrubs differed from that of forbs. Bee species diversity was highest on wax currant (Ribes cereum) and willow in early spring (April) and on black hawthorn (Crataegus douglasii) and mallow ninebark (Physocarpus malvaceus) later (i.e., June – July). Some bees showed a strong preference for wax currant and black hawthorn, both of which are more resistant to ungulate herbivory than other shrubs. Our results suggest that riparian restoration practitioners could consider using shrubs that provide forage to a diverse community of pollinators and improve stream health by shading and stabilizing banks. Planting bee‐friendly shrubs can help accomplish multiple restoration goals and leverage limited restoration funding. [ABSTRACT FROM AUTHOR]

Flood tolerance and growth rate of seedlings are often deciding criteria for wetland and riparian restoration plantings; however, these efforts often result in inadequate survival and growth of planted tree species. In an attempt to determine if parental seed source ecotype and seedling greenhouse preconditioning could influence survival and growth of two common restoration tree species, seeds from American sycamore (Platanus occidentalis L.) and willow oak (Quercus phellos L.) were collected from upland and floodplain sites in the Piedmont and Ridge and Valley regions of Virginia and were subjected to greenhouse flooding and drought preconditioning prior to field planting. American sycamore seedlings grown under normal conditions were 15 % shorter than seedlings subjected to flood preconditioning but had 13 % greater height than drought preconditioned seedlings. Preconditioning did not have a significant effect on willow oak seedling height. American sycamore seedlings sourced from dry ecotypes were 14 % taller than seedlings sourced from wet ecotypes, while willow oak seedlings sourced from wet ecotypes were 11 % taller than dry ecotype acorns. Seedlings from dry ecotype parents for American sycamore and seedlings from wet ecotype parents for willow oak may increase survival and growth of these species on marginal Piedmont agricultural sites. Adaptations observed after greenhouse preconditioning did not increase survivability or growth. Selection of seed sources from trees that exhibit good growth and vigor in landscape settings similar to the restoration area may increase the likelihood of meeting restoration goals and objectives. [ABSTRACT FROM AUTHOR]

Five years after the failure of the Fundão Dam in Brazil, no scientific report has been published regarding the rehabilitation interventions performed by the Renova Foundation, which is solely responsible for the rehabilitation of the Doce River Basin. This study aimed to assess the fluvial and riparian rehabilitation efforts performed by Renova, as well as to test and propose alternatives, when appropriate. Before the dam rupture, the fluvial system showed a single‐thread morphology that was sinuous and meandering. After the rupture, changes occurred in the river dynamics with strong sediment deposition in riparian areas, resulting in the loss of several meandering streams, oxbow‐lakes, lagoons, and fluvial islands. There was also a loss of the riparian vegetation, from 61% to 6%, as estimated by the Normalized Difference Vegetation Index (NDVI). Renova subjected nearly 61% of the study area to fluvial rehabilitation techniques, particularly using rip‐rap or larssen sheet piling (37%) and erosion control fibre blankets (17%). However, 50% of these interventions have been unsuccessful because the rip‐rap was poorly positioned and the biodegradable fibre blankets decomposed rapidly. We recommend changing the position of the rip‐rap from convex to concave banks and to avoid using biodegradable fibre blankets. Instead, we encourage the planting of riparian forests with native species to form buffer zone systems. Renova' riparian rehabilitation attempts were found to have low success rates, which was attributed to the unaddressed presence of toxic compounds, such as sodium and ether amine. However, our results proved that riparian rehabilitation using native species is feasible, if physical, chemical, biological, and phyto‐remediation strategies are adopted, to alleviate the ether amine and sodium toxicity. [ABSTRACT FROM AUTHOR]

Rivers and streams provide many ecosystem services, including provision of food, water purification, and nutrient abatement. Ecosystem functioning, the set of processes that regulate the fluxes of energy and matter, is the backbone of ecosystem services. A myriad of human impacts affects the functioning of running waters. To reduce these impacts, strategies for conservation and recovery of riparian vegetation, as well as direct interventions for stream restoration, have been carried out. However, these actions have been more limited in sub/tropical than in temperate regions. Based on case studies from southeastern Brazil and comparisons with their temperate counterparts, we illustrate and discuss how restoration of riparian canopy cover and stream reconfiguration through the addition of wood can influence two key ecosystem processes: nutrient retention and metabolism. Our findings indicate that the distinctive environmental features of the sub/tropical climate strongly shape the effect of stream restoration on ecosystem functioning. However, as in the temperate climate, effects are rarely monitored for a long time after the restoration, indicating the need for their longer‐term assessment. Understanding how restoration evolves over time to impact the functioning of sub/tropical streams is fundamental for the management and conservation of these strategic water bodies and the relevant ecosystem services they provide. [ABSTRACT FROM AUTHOR]

Riparian ecosystem restoration has been accomplished through exclusion of livestock using corridor fencing along hundreds of kilometers of streams in the western United States, for the benefit of riparian-obligate wildlife and endangered fishes. Yet, there are limited scientific studies that have evaluated more than short-term shifts in vegetation composition and diversity at a single location or handful of locations following grazing. We sampled riparian vegetation composition along 11-paired grazed and ungrazed (exclosed) stream reaches in northeastern Oregon. Exclosure ages ranged from 2 to >30 years and grazing treatments varied from light grazing every one out of three years to heavy season-long grazing. Species richness and diversity was higher in the ungrazed reaches (p = 0.002). The abundance of native sedges (Carex spp.) and broad-leaved forbs were also significantly (p ≤ 0.05) greater in ungrazed areas. In contrast, exotic species adapted to grazing such as Poa pratensis and Trifolium repens were more abundant in grazed stream reaches. The prevalence of hydrophytic species significantly increased (p ≤ 0.01) in ungrazed reaches, (based on wetland species indicator scores), indicating that wetland-dominated communities within the ungrazed stream reaches were replacing ones adapted to drier environments. The increased abundance of facultative and wetland-obligate species in ungrazed reaches compared to grazed reaches suggests that livestock grazing exacerbates those climate change effects also leading to warmer and drier conditions. Further, riparian-obligate shrub cover along the streambank was higher in 7 of 8 exclosures that were older than 5 years (p = 0.05). As a restoration approach, the inherent resilience of riparian ecosystems exhibited in ungrazed riparian zones suggest positive feedbacks to other beneficial ecosystem processes such as increased species and habitat diversity, increased carbon sequestration, enhanced allochthonous inputs and greater sediment retention, that would affect the aquatic and terrestrial biota, water quality, and stream morphology. [ABSTRACT FROM AUTHOR]

Competition with invasive grasses is one of the most important drivers of tree planting failures, especially in tropical forests. A widely disseminated weeding approach has been glyphosate spraying, the most used herbicide globally in forestry and ecosystem restoration. However, glyphosate use in restoration is highly controversial and requires further studies to elucidate its effects on restoration processes and the environment. We evaluated the use of glyphosate in riparian forest restoration and its impacts on tree planting costs, weed control efficiency, planted seedling performance, herbaceous and woody species regeneration, soil bacteria, and environmental contamination, using mowing treatments as a reference and based on a controlled experiment established in the Brazilian Atlantic Forest. Glyphosate spraying reduced by one‐half and one‐third the accumulated aboveground biomass of, respectively, weeds in general and of the invasive grass Urochloa decumbens compared to mowing treatments, and it reduced the cost by half. The performance of planted tree seedlings was markedly favored by glyphosate spraying compared to mowing treatments, as expressed by improved seedling height (~twice higher), crown area (~5× higher), and basal area (~5× higher); the regeneration of both native woody and ruderal herbaceous plants were also enhanced. Neither glyphosate nor its metabolite Aminomethylphosphonic acid (AMPA) residues were detected in either water runoff or soil samples, but they were found at relatively high concentrations in the runoff sediments (from 1.32 to 24.75 mg/kg for glyphosate and from 1.75 to 76.13 mg/kg for AMPA). Soil bacteria communities differed before and after glyphosate spraying in comparison to mowing plots (without glyphosate). Glyphosate spraying was far more cost effective than mowing for controlling U. decumbens and greatly improved the performance of planted tree seedlings and natural regeneration, while not leaving residues in soil and water. However, the changes in the structure of bacterial communities and high concentration of glyphosate and AMPA residues in runoff sediments highlight the need for caution when using this herbicide in riparian buffers. We present alternatives for reducing glyphosate use and minimizing its risks in tree planting initiatives. [ABSTRACT FROM AUTHOR]

Riparian ecosystems in montane areas have been degraded by mining, streamflow alterations, and livestock grazing. Restoration of ecological and economic functions, especially in high‐elevation watersheds that supply water to lower elevation urban and agriculture areas is of high priority. We investigated the response of riparian vegetation and bank stability following channel treatments and riparian habitat restoration along a segment of the upper Arkansas River south of Leadville, Colorado. The study area has been historically degraded by heavy‐metal mining and is designated a U.S. Superfund site. Additionally, trans‐basin water diversions and livestock grazing have contributed to channel widening and altered vegetation composition and cover. We used a before‐after‐control impact study design in four reaches with varied contamination and grazing history to assess restoration success. Before restoration, streambanks were dominated by graminoids and total vegetation cover varied among reaches with willow cover less than 16% in three reaches. Post‐restoration, changes in total vegetation cover fell short of projected goals, but willow cover was greater than 20% in all study reaches. The increase in woody cover likely contributed to reduced erosion and vegetation encroachment post‐restoration. Differences in functional group cover among reaches persisted post‐restoration and may be attributed to soil contamination levels and low willow seed rain and dispersal. These results highlight the importance of setting realistic restoration goals based on elevation and past land use. We recommend further remediation of fluvial tailings with low vegetation cover and continued monitoring of willow height and cover to determine if further restoration activities are needed. [ABSTRACT FROM AUTHOR]

River channels are among the most common landscape features on Earth. An essential characteristic of channels is sinuosity: their tendency to take a circuitous path, which is quantified as along-stream length divided by straight-line length. River sinuosity is interpreted as a characteristic that either forms randomly at channel inception or develops over time as meander bends migrate. Studies tend to assume the latter and thus have used river sinuosity as a proxy for both modern and ancient environmental factors including climate, tectonics, vegetation, and geologic structure. But no quantitative criterion for planform expression has distinguished between random, initial sinuosity and that developed by ordered growth through channel migration. This ambiguity calls into question the utility of river sinuosity for understanding Earth's history. We propose a quantitative framework to reconcile these competing explanations for river sinuosity. Using a coupled analysis of modeled and natural channels, we show that while a majority of observed sinuosity is consistent with randomness and limited channel migration, rivers with sinuosity =1.5 likely formed their geometry through sustained, ordered growth due to channel migration. This criterion frames a null hypothesis for river sinuosity that can be applied to evaluate the significance of environmental interpretations in landscapes shaped by rivers. The quantitative link between sinuosity and channel migration further informs strategies for preservation and restoration of riparian habitat and guides predictions of fluvial deposits in the rock record and in remotely sensed environments from the seafloor to planetary surfaces. [ABSTRACT FROM AUTHOR]

Along the U.S.‐Mexico border, an aggressive non‐native grass, giant cane (Arundo donax), grows in dense, nearly impenetrable stands along hundreds of kilometers of the Rio Grande/Bravo (RGB). Between 2008 and 2018, a diverse, multisector binational‐team repeatedly treated giant cane with prescribed fire and herbicide along 90 km of this binational river to restore aquatic and riparian habitat and native plant community composition. The large geographic scale, binational management response, treatment methods used, and development of a long‐term monitoring program to quantify treatment impacts on the RGB's riparian plant community underscore the unique aspects of this effort. Results of this decade‐long management experiment indicate that (i) the combination of a primary treatment of giant cane (using prescribed fire followed 4–6 weeks later by herbicide treatment of regrowth) and a secondary treatment (spot treatment of regrowth one or more years following primary treatment) was effective in reducing the extent and distribution of giant cane at relatively low cost, (ii) giant cane re‐establishment following treatment is often not rapid, nor dramatic; and (iii) as revealed by analysis of riparian vegetation monitoring data, eradication of dense stands of giant cane have fostered significant and long‐term reduction in giant cane cover and recovery of native woody riparian plant taxa. Important caveats to the long‐term viability of managing giant cane hinge on better understanding the consequences of herbicide use, securing funding to cover the cost of re‐treatment, and continuing river flow management focused on promoting the recovery of native riparian obligate plants over non‐natives. [ABSTRACT FROM AUTHOR]

Hydrological connectivity in river networks influences their response to environmental changes as local effects may extend downstream via flowing water. For example, localized changes in riparian forest conditions can affect stream temperatures, and these effects may propagate downstream. However, studies evaluating stream temperature responses to riparian forest management have not considered cumulative effects across entire watersheds. Improved understanding at these scales is needed because land managers are increasingly required to consider broad‐scale consequences of their actions. To address this question, we deployed a high‐density network of sensors across watersheds to examine stream temperature responses to experimental thinning of riparian forests. A riverscape approach that combined high‐resolution data throughout the study watersheds made it possible to examine local and downstream patterns of stream temperature at multiple spatial and temporal scales. We found that local responses of temperature to thinning varied widely depending on the intensity of thinning treatments. Downstream propagation of local responses extended from 100 m to over 1000 m and depended on the magnitude of the local response. We characterized these responses as a series of waveforms. In the watersheds with more intensive thinning, thermal responses occurred most often as an extended pulse where downstream increases in temperature attenuated gradually at variable distances. Although we observed no evidence of cumulative effects associated with thinning at the downstream extent of stream networks, effects emerged where thinning treatments were closely spaced (<400 m apart) and local warming did not dissipate with downstream distance. In a watershed with less intensive thinning, there was either no response or a localized pulse with no downstream propagation. Collectively, these patterns suggest that riparian forest thinning influenced downstream thermal conditions to varying extents depending on the intensity, scale, and spatial proximity of treatments. We found that a multiscale riverscape approach and conceptual framework based on contrasting waveforms provided a foundation for understanding the cumulative watershed effects of riparian thinning. The approach developed here can be adapted more broadly when evaluating downstream propagation of local changes in river networks and has direct implications for guiding restoration in riparian ecosystems. [ABSTRACT FROM AUTHOR]

The aim of WEQUAL project (WEb service centre for QUALity multidimensional design and tele-operated monitoring of Green Infrastructures) is the development of a system that is able to support a quick environmental monitoring of riparian areas subjected to the realization of new green infrastructures (GI). The Wequal’s idea is to organize a service center able to manage both the Web Platform and the whole data collection and analysis processes. Through a personal account, the final user (designer, technician, researcher) can get access to the service and requires the evaluation of alternatives GI projects. On the Web Platform, a set of algorithms runs in order to calculate, through automatic procedures, all the ecological criteria required to evaluate a quality environmental index that describes the eco-morphological value of the monitored riparian areas. For this aim, the WEQUI index was developed, which uses 15 indicators that are easy to monitor. In this paper, the approach for environmental data collection and the procedures to perform the automatic assessment of two of the ecological criteria are described. For the computation, the implemented algorithms use data including the vegetation indexes, Digital Terrain Model (DTM), Digital Surface Model (DSM) and a 3D point cloud classification. All the raw data are collected by UAVs (Unmanned Aircraft Vehicle) equipped with a 3D Lidar, multispectral camera and RGB camera. Interpreting all the raw data collected by these sensors, using a multi-attribute approach, the WEQUI index is assessed. The computed ecological index is then used to assess the riparian environmental quality at ex-ante and ex-post river stabilization works. This index, integrated with additional not-technical or not-ecological indicators such as investment required, maintenance costs or social acceptance, can be used in multicriteria analyses in order to evaluate the intervention from a wider point of view. The platform is expected to be attractive for GI designers and policy makers by providing a shared environment, which is able to integrate the method of detection and evaluation of complex indexes and a multidimensional evaluation supported by an expert guide.

Quantitative evaluation of ecological restoration effects (EREs) is essential to provide operational feedback and implement adaptive management for future riparian restoration. This manuscript aims to develop a multi-scale evaluation method of EREs based on remote sensing observations, which uses the composite index of physical structural integrity (PSI) to indicate riparian condition. The riparian EREs were quantitatively assessed by comparing the post-restoration PSI values with the ecological reference status derived from pre-restoration surveys. In addition, ecological partitioning was adopted to identify the vulnerable riparian areas and explore the influence indicators of ecological restoration. In this paper, we used the case study of the Liaohe River, the first protected area aimed to recover the riparian ecosystem in China, to evaluate the riparian EREs at three spatial scales using Landsat time series images from 1980 to 2019. Results indicated that: (1) the pre-restoration riparian ecosystem exhibited an clear degradation trend and ecological conservation was urgent; (2) riparian restoration is a continuous and heterogeneous ecological process, the project had not yet met its objectives in 2016 with a low ERE value of 49.1 (Poor), while achieved a significant success in 2019 with the ERE value of 68.8 (Very good); (3) the limited restoration partitions with a ERE value below 60 accounted for 42.8% of riparian zones, which were the fragile riparian ecosystems and mainly distributed in reach D and F; and (4) the dominant factors for riparian restoration were canopy coverage, human disturbance and natural vegetation percent. This study is expected to provide a practical and feasible approach for evaluating the riparian EREs and supporting the future river management, in particular for rivers lack of long-term monitoring data.

Summary: Direct seeding is increasingly being used as a cost‐effective revegetation technique. Successful outcomes from direct seeding rely on effective weed control, particularly during the vulnerable seedling establishment phase. Post‐sowing weed control options are constrained by the need to protect seedlings from damage and few studies have compared the effectiveness of different weed control techniques. We evaluated the effect of preliminary hand weeding (with subsequent spraying), spraying monthly or spraying quarterly with glyphosate, on woody seedling emergence, survival and growth in trials sown either in spring or autumn at a riparian site in Victoria, southeastern Australia. Seedling numbers were recorded monthly for 6 months and at 12 months after sowing, with seedling survival and heights assessed at 12 months. Total seedling numbers were higher in subplots initially hand weeded than in subplots sprayed on either a monthly or quarterly basis, regardless of when direct seeding occurred, but weed control treatment had no effect on seedling survival. These results indicate that post‐sowing spraying limited rates of seedling emergence, either directly or indirectly. For direct seeding, hand weeding in the first few months after sowing may maximise rates of woody seedling emergence, while spraying with glyphosate may inhibit seedling emergence. [ABSTRACT FROM AUTHOR]

Climate change models indicate that stream temperatures within much of the Columbia River Basin will increase significantly in the next 50 years leading to inhospitable conditions for salmonid fishes in several stream reaches. Restoration measures such as riparian planting, maintaining instream flows, and large wood (LW) placement are thought to ameliorate the impacts of climate change on stream temperatures. While LW placement is known to improve habitat complexity, it is unclear whether it will also help reduce summer stream temperatures. To help understand the influence of LW placement on stream temperatures, we monitored nine interior Columbia River Basin LW projects using an extensive posttreatment study design. We mapped stream bottom temperatures, topography, and physical habitat in paired treatment (LW placement) and control reaches to compare water temperatures and cool‐water patches between reaches. We found no difference in the mean or the variance in overall reach temperatures or thalweg temperatures between treatment and control reaches. Mapping found variation in water temperatures of less than 0.5°C within reaches, making mapping of cool‐water patches impractical and further emphasized the lack of temperature differences. Our results indicate that LW placement projects in the interior Columbia River Basin do not appear to be decreasing reach‐scale summer water temperatures or creating cool water refugia for fishes. Moreover, the current configuration and implementation of LW placement projects, which typically focus on placing wood on banks and channel margins, are unlikely to ameliorate the effects of climate change on stream temperatures. [ABSTRACT FROM AUTHOR]

Riparian habitat in the southwestern United States has undergone substantial degradation over the past century, prompting extensive management and restoration of these critical ecosystems. Most restoration efforts, however, do not account for life history traits or riverine complexity that may influence genetic diversity and structure. Here, we use simple sequence repeat markers in four southwestern riparian species (Populus fremontii, Salix gooddingii, S. exigua, and Prosopis glandulosa) that occupy a geographically complex region to address four questions: (1) How is river connectivity related to genetic diversity and structure? (2) How do mating systems and dispersal mechanisms influence gene flow? (3) Is genetic diversity influenced by unidirectional water flow? (4) How do unregulated tributary and regulated river flows affect clonality and associated diversity? Our results identify five findings: (1) Patterns of genetic diversity and structure vary substantially across different species; (2) species with geographic distributions that include a large, perennial river exhibit the least genetic structure; (3) mating system, clonality, and seed dispersal are related to genetic structure; (4) genetic diversity is variable among species and populations, but does not increase or decrease unidirectionally; and (5) clonality and associated diversity does not differ along a regulated river relative to unregulated tributaries. Our multispecies approach to understanding how riverine complexity and life history traits influence genetic diversity and structure could be incorporated into management efforts to more closely match riparian species with their unique environments, thereby facilitating restoration success. [ABSTRACT FROM AUTHOR]

Landscape homogenization and the removal of riparian areas have altered stream ecosystems worldwide. Numerous conservation programmes attempt to improve water quality and increase instream habitat heterogeneity to elicit desired biological responses. However, the effectiveness of many conservation efforts on isolated stream fragments remains unknown, especially in grassland regions.The effects of grassland conservation practices and the re‐establishment of riparian corridors in the James River basin, South Dakota (USA) on stream water quality, habitat availability and aquatic macroinvertebrate and fish assemblages were studied in an agriculturally dominated prairie landscape.Grassland conservation efforts may have repaired riparian condition, reduced turbidity and created more diverse instream habitat complexes at conservation sites based on comparisons with paired reference reaches. Reference sites were relatively homogeneous, with prevalent siltation, bank erosion and disturbances to the riparian vegetation. Owing to significant riparian vegetation development, overhanging and aquatic vegetation, benthic detritus and woody materials were significantly more common at conservation reaches.Restoration efforts that assume 'if you (re‐)build it, they will come' (i.e. the 'field of dreams' hypothesis) underestimate other important barriers to biodiversity restoration in dynamic, grassland riverscapes. Although aquatic organisms in grassland ecosystems are adapted to rapidly inhabit available habitats, the development of niche space at conservation reaches did not directly result in colonization by aquatic life.Grassland management actions did not address stream connectivity issues or overcome land use influences elsewhere in the riverscape that may govern the responses of aquatic macroinvertebrates and fish. Stream fragmentation and continuing, damaging land use patterns seemed to exceed the positive effects of restoring isolated stream reaches in these heavily degraded catchments. Catchment‐scale management strategies that combine reach‐level restoration actions with efforts to improve connectivity are likely to be more successful in degraded riverscapes. [ABSTRACT FROM AUTHOR]

Unmanned Aerial Vehicles (UAVs) offer new opportunities for accurate, repeatable vegetation assessments, which are needed to adaptively manage restored habitat. We used UAVs, ground surveys, and satellite imagery to evaluate vegetation metrics for three riparian restoration sites along the Colorado River in Mexico and we compared the data accuracy and efficiency (cost and time requirements) between the three methods. We used an off‐the‐shelf UAV coupled with a multispectral sensor to determine Normalized Difference Vegetation Index (NDVI) and vegetation cover. We were unable to accurately classify vegetation by individual species, but by grouping riparian species of interest (cottonwood‐willow, mesquite, shrubs), we achieved high overall model accuracies of 87–96% across sites (Kappa = 0.82–0.95). Producer's and user's accuracies were moderate to high for target vegetation classes (69–100%). UAV and ground‐survey vegetation percent cover differed due to differences in methodologies (UAVs measure aerial cover; ground surveys measure foliar cover) and sources of error for each method. Correlations between UAV and ground survey vegetation cover were moderate (rs(90) = 0.24–0.58, p < 0.05). UAV NDVI (0.50–0.61) was significantly higher than Landsat NDVI (0.40–0.45) for all sites (p < 0.0001), likely due to presence of shadows with high NDVI values in UAV imagery. UAV NDVI, Landsat NDVI and UAV total vegetation cover were strongly correlated (rs(90) = 0.72–0.85, p < 0.05). UAV surveys were more labor‐ and cost‐ intensive than ground surveys in the first year, but were slightly less so in the second year. We conclude that UAVs can provide efficient, accurate assessments of riparian vegetation, which can be used in restoration site management. Due to UAV limitations to assess vegetation in a multi‐layered canopy and inability to classify individual riparian species with similar spectral signals, we recommend a combined approach of UAV and ground surveys. [ABSTRACT FROM AUTHOR]

The tailings spilled by the Fundão Dam rupture in the Doce River basin (Brazil) had a high pH, elevated sodium (Na) and ether amine, and low soil organic matter. With the aim of decreasing the toxic compounds, we established 2 remediation strategies: treatment 1, phytoremediation with tolerant native species of the Atlantic Forest cultivated on scraped sediment plus the incorporation of organic matter; and treatment 2, phytoremediation with native species plus superficial deposition of organic matter. The experimental site was compared with a degraded site that the dam tailings had reached and with a preserved site, a fragment of preserved Atlantic Forest. After 12 mo, plants showed an outstanding growth, especially after treatment 1 (~4 m), and the remediation procedures resulted in significant decreases in pH (from 8.0 to ~ 6.0), Na (from 154 to 22–35 mg/kg), electrical conductivity, and ether amine (from 6.0 to 0.5 mg/kg) in both treatments. By contrast, ammonium, a product of ether amine degradation, showed a significant increase in the experimental site, along with a significant increase in nitrate and improvement of soil microbial populations assessed by phospholipid fatty acid analysis. The treatments also improved soil fertility in the experimental site, as estimated by soil nutrients, cation exchange capacity, and soil aggregation. Based on the parameters analyzed, a principal component analysis showed that samples from the degraded site and the preserved site clustered in an opposite position and those from the experimental site clustered in an intermediate position but closer to the samples from the preserved site. Overall, our results demonstrated that the remediation procedures adopted were effective and resulted in rehabilitation of a riparian forest contaminated with dam tailings that included Na and ether amine. Environ Toxicol Chem 2021;40:2359–2373. © 2021 SETAC. [ABSTRACT FROM AUTHOR]

Hydrologic and physical gradients influence vegetation zonation and can form the basis of riparian revegetation design. We present a new data‐driven method to develop riparian revegetation designs by relating the ground height above river (HAR) or a low streamflow water surface as a groundwater proxy to existing vegetation cover types and applying those relationships to design conditions. Steps in the process are as follows: (1) map existing vegetation within the riparian corridor; (2) construct existing and design topographic and groundwater digital elevation models (DEMs), and then difference those DEMs to create a HAR detrended DEM (HAR dtDEM); (3) define existing vegetation habitat zones using the relationship between existing HAR dtDEM and mapped vegetation cover types; (4) apply habitat zone boundaries to detrended design topography; and (5) develop planting schematics using habitat zones and detrended design topography. We developed a revegetation design for a rehabilitation site on the Trinity River, California, using the HAR dtDEM method. We used a data‐driven method to define five habitat zones in riparian areas: aquatic, emergent margin, mesic, mesic–xeric transition, and xeric zones. Zonal boundaries were identified using four criteria: (1) capillary fringe elevation above the low flow water surface, (2) shifts from herbaceous to woody‐dominated cover types, (3) a difference equal to or >0.5 m between two adjacent ranked cover types, and (4) locations where a linear trendline intersected median HAR values or where a group of regression residuals changed from positive to negative or vice versa. The capillary fringe height was the most effective method when determining vegetation zones near the channel. The shift between herbaceous and woody‐dominated cover types defined the boundary between the emergent margin and mesic zone. Elevation increases >0.5 m between adjacent ranked cover types defined the upper and lower mesic–xeric transition zone boundaries best. Comparing linear residuals was most useful for separating drier cover types occurring on higher ground surfaces. Existing habitat zone boundaries were applied to detrended design topography to direct which selected native plant species could be arranged within habitat zones to improve planting survival and increase ecological function following rehabilitation. [ABSTRACT FROM AUTHOR]

Abstract Hydrologic and physical gradients influence vegetation zonation and can form the basis of riparian revegetation design. We present a new data‐driven method to develop riparian revegetation designs by relating the ground height above river (HAR) or a low streamflow water surface as a groundwater proxy to existing vegetation cover types and applying those relationships to design conditions. Steps in the process are as follows: (1) map existing vegetation within the riparian corridor; (2) construct existing and design topographic and groundwater digital elevation models (DEMs), and then difference those DEMs to create a HAR detrended DEM (HAR dtDEM); (3) define existing vegetation habitat zones using the relationship between existing HAR dtDEM and mapped vegetation cover types; (4) apply habitat zone boundaries to detrended design topography; and (5) develop planting schematics using habitat zones and detrended design topography. We developed a revegetation design for a rehabilitation site on the Trinity River, California, using the HAR dtDEM method. We used a data‐driven method to define five habitat zones in riparian areas: aquatic, emergent margin, mesic, mesic–xeric transition, and xeric zones. Zonal boundaries were identified using four criteria: (1) capillary fringe elevation above the low flow water surface, (2) shifts from herbaceous to woody‐dominated cover types, (3) a difference equal to or >0.5 m between two adjacent ranked cover types, and (4) locations where a linear trendline intersected median HAR values or where a group of regression residuals changed from positive to negative or vice versa. The capillary fringe height was the most effective method when determining vegetation zones near the channel. The shift between herbaceous and woody‐dominated cover types defined the boundary between the emergent margin and mesic zone. Elevation increases >0.5 m between adjacent ranked cover types defined the upper and lower mesic–xeric transition zone boundaries best. Comparing linear residuals was most useful for separating drier cover types occurring on higher ground surfaces. Existing habitat zone boundaries were applied to detrended design topography to direct which selected native plant species could be arranged within habitat zones to improve planting survival and increase ecological function following rehabilitation.

Abstract Successful restoration of riparian habitats and functions depends in part on selection of plant species that are suited to local geomorphic and climatic conditions, which often relies on contemporary reference sites to characterize target riparian vegetation communities. In heavily modified landscapes, a lack of undisturbed sites hinders the description of reference conditions to help guide planning efforts. In lieu of contemporary reference sites, we used historical Public Land Survey data from the late 1800s and early 1900s to document historical streamside vegetation at 1685 sites distributed throughout the Columbia River basin. We used those data to construct a random forest classification model using climatic and geomorphic variables to predict the probability of occurrence of riparian vegetation groups (conifer, deciduous, shrub, and willow) and individual taxa (fir, pine, cedar, cottonwood, alder, sagebrush) for all stream reaches with bankfull width >6 m in the interior Columbia River basin. The most common predictor variables included in the best models for vegetation groups or individual taxa were mean annual precipitation, minimum temperature, elevation, and bankfull width. For some taxa, temperature range and floodplain width were also important predictors. The probability maps indicate that riparian zones were likely dominated by willow species in semi‐desert regions and by conifer species in the humid mountain regions. Deciduous species dominated riparian areas in transition zones between conifer forests and semi‐deserts. Species distributions suggest that streams in the semi‐deserts were likely characterized by little shade and low wood abundance, whereas streams in the humid mountains would have been more heavily shaded with high wood abundance. The transitional deciduous areas were likely shaded with moderate wood abundance. Historical trends in air temperature and precipitation suggest relatively small changes in climate since the time of the surveys, indicating that current species ranges are likely similar to historical species ranges. Hence, these maps can be used to help identify suitable taxonomic groups and expected riparian functions for riparian restoration in the Columbia River basin, with appropriate adjustments made to site‐specific restoration designs to account for model uncertainty, future climate change, or land use constraints.

Forest conversion is one of the greatest global threats to biodiversity, and land‐use change and subsequent biodiversity declines sometimes occur over a variety of underlying geologies. However, how forest conversion and underlying geology interact to alter biodiversity is underappreciated, although spatial variability in geology is considered an integral part of sustaining ecosystems. We aimed to examine the effects of forest conversion to farmland, the underlying geology, and their interaction on the stream fishes' diversity, evenness, and abundance in northeastern Japan. We disentangled complex pathways between abiotic and biotic factors with structural equation modeling. Species diversity of stream fishes was indirectly shaped by the interaction of land use and underlying geology. Diversity declined due to nutrient enrichment associated with farmlands, which was mainly the result of changes in evenness rather than by changes in species richness. This impact was strongest in streams with volcanic geology with coarse substrates probably because of the differential responses of abundant stream fishes to nutrient enrichment (i.e., dominance) and the high dependency of these fishes on large streambed materials during their life cycles. Our findings suggest that remediation of deforested or degraded forest landscapes would be more efficient if the interaction between land use and underlying geology was considered. For example, the negative impacts of farmland on evenness were larger in streams with volcanic geology than in other stream types, suggesting that riparian forest restoration along such streams would efficiently provide restoration benefits to stream fishes. Our results also suggest that land clearing around such streams should be avoided to conserve species evenness of stream fishes. Article impact statement: Forest restoration projects should consider the potentially significant influences of the interaction between land use and the underlying geology on biodiversity. [ABSTRACT FROM AUTHOR]

The Demnitzer Millcreek catchment (DMC), is a 66 km2 long‐term experimental catchment located 50 km SE of Berlin. Monitoring over the past 30 years has focused on hydrological and biogeochemical changes associated with de‐intensification of farming and riparian restoration in the low‐lying landscape dominated by rain‐fed farming and forestry. However, the hydrological function of the catchment, which is closely linked to nutrient fluxes and highly sensitive to climatic variability, is still poorly understood. In the last 3 years, a prolonged drought period with below‐average rainfall and above‐average temperatures has resulted in marked hydrological change. This caused low soil moisture storage in the growing season, agricultural yield losses, reduced groundwater recharge, and intermittent streamflows in parts of an increasingly disconnected channel network. This paper focuses on a two‐year long isotope study that sought to understand how different parts of the catchment affect ecohydrological partitioning, hydrological connectivity and streamflow generation during drought conditions. The work has shown the critical importance of groundwater storage in sustaining flows, basic in‐stream ecosystem services and the dominant influence of vegetation on groundwater recharge. Recharge was much lower and occurred during a shorter window of time in winter under forests compared to grasslands. Conversely, groundwater recharge was locally enhanced by the restoration of riparian wetlands and storage‐dependent water losses from the stream to the subsurface. The isotopic variability displayed complex emerging spatio‐temporal patterns of stream connectivity and flow duration during droughts that may have implications for in‐stream solute transport and future ecohydrological interactions between landscapes and riverscapes. Given climate projections for drier and warmer summers, reduced and increasingly intermittent streamflows are very likely not just in the study region, but in similar lowland areas across Europe. An integrated land and water management strategy will be essential to sustaining catchment ecosystem services in such catchment systems in future. [ABSTRACT FROM AUTHOR]

The western distinct population segment of yellow‐billed cuckoo (Coccyzus americanus; western cuckoo) has been extirpated from most of its former breeding range in the United States because of widespread loss and degradation of riparian cottonwood (Populus spp.)‐willow (Salix spp.) forests. Restoration and management of breeding habitat is important to the recovery of this federally threatened species, and identification of high‐quality breeding habitat can help improve the success of recovery. In 2005, the Lower Colorado River Multi‐Species Conservation Program, a long‐term, multi‐agency effort, was initiated to maintain and create wildlife habitat within the historical floodplain of the lower Colorado River (LCR) for federally endangered and threatened species, including western cuckoos. We conducted an empirical, multi‐scale field investigation from 2008–2012 to identify habitat characteristics selected by nesting western cuckoos along the LCR. Multiple logistic regression models revealed that western cuckoos selected nest sites characterized by increased densities of small, native, early successional trees measuring 8–23 cm diameter at breast height, and lower diurnal temperature compared to available habitat in restoration and natural forests. Nesting cuckoos selected sites with increased percent canopy closure, which was also important for nest success in restoration sites along the LCR. Our results show habitat components selected by nesting western cuckoos in restoration and natural riparian forests and can help guide the creation, enhancement, and management of riparian forests with habitat conditions necessary to promote nesting of western cuckoos. © 2021 The Wildlife Society. Our results can help guide the creation, enhancement, and management of riparian forests with desired habitat conditions necessary to promote nesting of the federally threatened western yellow‐billed cuckoo. The strategic placement of small native trees at high densities in a specific site or the management of riparian forests for high density patches of early successional native trees could significantly improve or increase optimal nesting habitat for western cuckoos in restoration and natural riparian forests. [ABSTRACT FROM AUTHOR]

Investigating terrestrial determinants impacts on surface water quality is critical for watershed management. This research work reports the terrestrial determinants influence on surface water quality at multiple spatial scales at two trans-boundary rivers of Pakistan: The Ravi and Sutlej. This study is based on 18 physicochemical and trace elements (pH, turbidity, electrical conductivity (EC), NO3, total dissolved solid (TDS), chemical oxygen demand (COD), biological oxygen demand (BOD), dissolved oxygen (DO), hardness, total nitrogen, phosphorus, Cu, Pb, As, Cr, Mn, Zn, and Cd) from 15 water quality monitoring stations. Terrestrial determinants especially village land use, coarse grained soil (high permeability) and mean slope (high erosion) can impair surface water quality. On the other hand, fine grained soil can protect stream health due to strong retention capacity and low infiltration capability. All spatial scales best explained terrestrial determinants-water quality relationship. Conservative practices are suggested at riparian as well as subbasin scale to account for the nearest and furthest pollutants sources. Restoration of riparian ecosystems should be a high priority for water quality enhancement in particular along the Ravi and Sutlej rivers and the two plains where there are intensive human activities at village level. [ABSTRACT FROM AUTHOR]

The riparian ecosystems of the Western Ghats are highly diversified tropical forest ecosystems. The synergic effect of various threats may adversely affect and reduce the capacity of these riparian ecosystems to resilience, even though they have specific adaptations for living in extreme conditions. These diversity‐rich riparian ecosystems provide critical ecological services such as influencing environmental processes, acting as habitats for both terrestrial and aquatic biota, and supporting the livelihood of the surrounding community. Hence the restoration of such damaged ecosystems is highly significant. This article presents a scheme for sustainable restoration of the disturbed riparian ecosystems with the involvement of multi‐stakeholders. The three‐stage scheme ensures the support and livelihood of the local community, along with the ecological restoration of riparian ecosystems using nature‐based solutions with a scientific approach. The restoration will enhance the ecosystem services, climate change adaptations, and resilience, as well as the carbon sequestration capacity of the tropical region. [ABSTRACT FROM AUTHOR]

Successful restoration of riparian habitats and functions depends in part on selection of plant species that are suited to local geomorphic and climatic conditions, which often relies on contemporary reference sites to characterize target riparian vegetation communities. In heavily modified landscapes, a lack of undisturbed sites hinders the description of reference conditions to help guide planning efforts. In lieu of contemporary reference sites, we used historical Public Land Survey data from the late 1800s and early 1900s to document historical streamside vegetation at 1685 sites distributed throughout the Columbia River basin. We used those data to construct a random forest classification model using climatic and geomorphic variables to predict the probability of occurrence of riparian vegetation groups (conifer, deciduous, shrub, and willow) and individual taxa (fir, pine, cedar, cottonwood, alder, sagebrush) for all stream reaches with bankfull width >6 m in the interior Columbia River basin. The most common predictor variables included in the best models for vegetation groups or individual taxa were mean annual precipitation, minimum temperature, elevation, and bankfull width. For some taxa, temperature range and floodplain width were also important predictors. The probability maps indicate that riparian zones were likely dominated by willow species in semi‐desert regions and by conifer species in the humid mountain regions. Deciduous species dominated riparian areas in transition zones between conifer forests and semi‐deserts. Species distributions suggest that streams in the semi‐deserts were likely characterized by little shade and low wood abundance, whereas streams in the humid mountains would have been more heavily shaded with high wood abundance. The transitional deciduous areas were likely shaded with moderate wood abundance. Historical trends in air temperature and precipitation suggest relatively small changes in climate since the time of the surveys, indicating that current species ranges are likely similar to historical species ranges. Hence, these maps can be used to help identify suitable taxonomic groups and expected riparian functions for riparian restoration in the Columbia River basin, with appropriate adjustments made to site‐specific restoration designs to account for model uncertainty, future climate change, or land use constraints. [ABSTRACT FROM AUTHOR]

Ecological restoration is an essential strategy for mitigating the current biodiversity crisis, yet restoration actions are costly. We used systematic conservation planning principles to design an approach that prioritizes restoration sites for birds and tested it in a riparian forest restoration program in the Colorado River Delta. Restoration goals were to maximize the abundance and diversity of 15 priority birds with a variety of habitat preferences. We built abundance models for priority birds based on the current landscape, and predicted bird distributions and relative abundances under a scenario of complete riparian forest restoration throughout our study area. Then, we used Zonation conservation planning software to rank this restored landscape based on core areas for all priority birds. The locations with the highest ranks represented the highest priorities for restoration and were located throughout the river reach. We optimized how much of the available landscape to restore by simulating restoration of the top 10–90% of ranked sites in 10% intervals. We found that total diversity was maximized when 40% of the landscape was restored, and mean relative abundance was maximized when 80% of the landscape was restored. The results suggest that complete restoration is not optimal for this community of priority birds and restoration of approximately 60% of the landscape would provide a balance between maximum relative abundance and diversity. Subsequent planning efforts will combine our results with an assessment of restoration costs to provide further decision support for the restoration-siting process. Our approach can be applied to any landscape-scale restoration program to improve the return on investment of limited economic resources for restoration. • Systematic conservation planning tools can be useful in landscape-scale restoration planning. • Bird-community abundance was maximized when 80% of the landscape was restored and diversity was maximized when 40% of the landscape was restored. • Six species were positively associated with increasing restoration area. • Five species were positively associated with intermediate levels of restoration. • Three species were negatively associated with increasing restoration area. [ABSTRACT FROM AUTHOR]

Riparian restoration in the southwestern United States frequently involves planting cottonwood (Populus spp.) and willow (Salix spp.). In the absence of flooding and gap‐forming disturbance, planted forests often senesce without further young tree recruitment. This has largely been the case in California riparian systems that historically supported state‐endangered western Yellow‐billed Cuckoo (Coccyzus americanus; Cuckoo). A decline in Cuckoo population numbers in the past 30 years has been associated with forest maturation. Other riparian species of concern show a concomitant decline, indicating the problem is not specific to Cuckoos. Although varying hypotheses exist for recent decline, alternative management practices have not been sufficiently explored to rule out breeding ground habitat quality as a major contributing factor. Few intensive Cuckoo datasets exist to test hypotheses about breeding habitat quality due to extremely low populations in the remaining occupied sites. We used a historical (1986–1996) spot mapping dataset from the South Fork Kern River Valley, CA to identify vegetation characteristics related to Cuckoo and five other sensitive riparian bird territory densities. We found Cuckoo densities were positively associated with increased vertical vegetative structure 1–5 m above ground with a threshold for mean tree height. Sensitive species densities were also related to vertical structure and started to decline with stand height greater than 6–8 m. Naturally regenerated sites had higher densities of most sensitive bird species than planted sites. We provide ideas for restoring mature forest with little vertical structure. [ABSTRACT FROM AUTHOR]

Current restoration monitoring protocols have been developed for active restoration projects (based on planting seedlings) and little is known about their applicability in assessing vegetation resulting from passive restoration, an important knowledge gap for the restoration of tropical and subtropical forests. The present study was developed in a 12-year-old subtropical riparian forest undergoing passive restoration (based on spontaneous natural regeneration), and aimed to evaluate the regenerating vegetation using two monitoring protocols developed for active ecological restoration. The following indicators of restoration success were evaluated: canopy cover; basal area; above-ground biomass; total richness; richness and density of regenerating trees. Passive restoration strategy has been found to be successful in the study area as the observed values for the indicators (except basal area and biomass) were above reference values specified for a 12-year-old active restoration. Our results also show that for most of the indicators of restoration success, the reference values established for the evaluation of active restoration projects may be surpassed through unassisted natural regeneration, suggesting the feasibility of the application of these monitoring protocols for the evaluation of passive restoration projects. [ABSTRACT FROM AUTHOR]

Nutrient run-of from mid'western agricultural operations into the Mississippi River has resulted in unconscionable destruction m the river': ecological, economic, and recreational. The sovereign interests of downstream riparian states-particularly Louisiana and Mississippi-in the use and health of their natural resources clash with the economic ambitions of upstream polluters. In response to this well-documented problem, the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force formed in 1997 to readdress eutrophication in the Gulfof Mexico. which is one of the most visible and impactftil mar*stations of nutrient pollution in the world. ABer twenty years, the eflects have greatly worsened and the need to redress the harm immediately is imperative, lest the states resort to more direct. graver action to secure their rights to a usable river. When an individual's actions harm another's property, the injured individual can recover under a number of causes of action. When a state harms another state, the avenue for recourse is less clear but the stakes are much greater. Several pathways to fixing the nutrient pollution in the Mississippi River have been considered, including litigation via the Clean Water Act. a federal common-law nuisance action, and an interstate compact. However, other states encountering water problems have tried these options and failed. Prudence directs consideration of another solution. One such solution, and the fbcus of this Article, is the pursuit of an equitable remedy through the assertion of riparian rights in an original jurisdiction action before the Supirme Court of tile United States. An equitable remedy should take the form of an equitable apportionment decree. Such actions are becoming moi·e fequent (even if asserted under other names). This Article will consider the strengths and weaknesses of bringing an original action be/bre the Supreme Court of the United States for an equitable apportionment decree of the Mississippi River. [ABSTRACT FROM AUTHOR]

As the field of ecological restoration grows, novel methods to improve the effectiveness of restoration projects are being advanced and tested. Here, measured plant functional traits are used to select a native planting palette for the restoration of riparian habitat at Strawberry Creek, a heavily invaded urban ecosystem in Berkeley, CA. I partnered with an active restoration program and together we focused on methods to prevent re-invasion by a dominant non-native understory species and reduce nitrogen pollution of the riparian ecosystem. uptake study revealed a marginally significant (0.05

Implementation and evaluation of conservation efforts requires an understanding of the habitat selection and reproductive success of endangered populations. As populations recover, established territory holders may force new arrivals into lower quality habitat, which can reduce reproductive success, especially in disturbed landscapes where suitable habitat is scarce. The endangered Western Yellow-breasted Chat (Icteria virens auricollis) population in the fragmented riparian zone of the Okanagan Valley, British Columbia, Canada, has rapidly increased in response to habitat restoration. During this population increase from 2002 to 2014, we monitored 485 chat nests in 157 breeding territories to evaluate the influences of habitat selection, habitat restoration, and brood parasitism by Brown-headed Cowbirds (Molothrus ater) on reproductive performance. We found that, in protected reference sites, breeding territories that were occupied in the early years of the study had higher percent shrub cover than territories that were first occupied in the later years of the study, indicating that chats preferred territories with high shrub cover. Conversely, in restoration sites, later-occupied territories had similarly high shrub cover as earlier-occupied territories, suggesting that restoration activities enabled chats to continually settle in territories with high shrub cover. Yet, we did not find strong evidence that nest site vegetation characteristics or habitat restoration influenced reproductive performance. Instead, the high rate of brood parasitism (49%), which reduced nest success and productivity, was the dominant influence on reproductive performance. However, this recovering population still had high daily nest survival (0.974) and productivity (2.72 fledglings per successful nest) compared with other riparian songbirds and the high parasitism rate did not prevent the population from increasing. Thus, conservation efforts for Yellow-breasted Chats should focus on restoring riparian shrubs, even within heavily developed landscapes, to increase the number of potential breeding territories, while also quantifying how brood parasitism influences reproductive performance. LAY SUMMARY In landscapes where undisturbed, high-quality habitat is scarce, some birds may be forced to occupy low-quality habitat. Habitat restoration may provide more high-quality habitat. The endangered population of Yellow-breasted Chats in British Columbia increased in abundance from 2002 to 2014 in response to habitat restoration efforts. We investigated 2 questions: (1) Do chats prefer to nest in areas with certain vegetation characteristics? and (2) What effects do vegetation characteristics and parasitism by Brown-headed Cowbirds, which lay their eggs in chat nests, have on chat reproductive success? Settlement patterns indicated that chats prefer to occupy breeding territories with high shrub cover. However, Brown-headed Cowbirds parasitized half of all chat nests, and whether or not a nest was parasitized was more important than vegetation characteristics in determining how many chat fledglings were produced. Habitat restoration efforts provided more suitable habitat for this recovering population but did not reduce how often chat nests were parasitized. Chats in this population still have relatively high reproductive success and therefore are not as vulnerable to cowbird parasitism as other songbirds. [ABSTRACT FROM AUTHOR]

Cottonwoods, Populus trees, provide the foundation for riparian woodlands around the Northern Hemisphere but have declined partly due to river damming and water withdrawal. Cottonwood conservation requires periodic seedling replenishment, which depends upon coordinating river flows with the limited seed dispersal interval. Tracking seed dispersal phenology is laborious and we recognized a complementary approach with photographs and videos of prolific cottonwood seed release on internet websites. We searched the internet for 'cottonwood seeds' or 'summer snow', and about 800 images were posted since 2004. The 337 reports from North America with dates and/or locations revealed sequential seed dispersal in the American Southwest, the Pacific Northwest, the Great Lakes Region, and finally Alaska. Mean dispersal was June 3, with two-thirds of reports in the flanking four week interval. Dispersal was later at higher latitude and elevation, and a two-factor regression model provided 85% accuracy with reported peak dispersal from nine previous studies across western North America. The 49 Eurasian reports also revealed later seed dispersal with increasing latitude. This study revealed the utility of internet searching for tracking cottonwood seed dispersal, which could facilitate environmental flows for riparian restoration. More broadly, internet reports could reveal spatiotemporal patterns in other natural phenomena. [ABSTRACT FROM AUTHOR]

We investigated the relative role of manager traits and decisions for explaining the impact of riparian restoration. To do this, we used the difference in vegetation between post-restoration and controls for 243 pairs of sites to create a success index. We then determined how much variability in success could be explained by physical variables that directly impact vegetation (environment and weed removal) versus human variables (characteristics of the people who managed those sites and their management decisions). More than 60% of the variability in vegetation change could be explained, with human variables increasing adjusted R-square values of physical-only models by an average of 47%. Restoration "success" was positively associated with an increase in the number of collaborators, the number of information sources used, and the relative priority of plant-related goals. Worse outcomes were associated with an increase in the number of roles the manager held, monitoring frequency, and with higher manager education level. These results point to the indirect impacts of the human element, and specifically supports recommendations to include multiple partners and set specific goals. To our knowledge, this is the first time the importance of human characteristics as drivers of restoration outcomes has been quantified. [ABSTRACT FROM AUTHOR]

Linked hydrologic, hydraulic, and ecological models can facilitate planning and implementing water releases from reservoirs to achieve ecological objectives along rivers. We applied a flow‐ecology model, the Ecosystem Functions Model (HEC‐EFM), to the Bill Williams River in southwestern USA to estimate areas suitable for recruitment of riparian tree seedlings in the context of managing flow releases from a large dam for riparian restoration. Ecological variables in the model included timing of seed dispersal, tolerable rates of flow recession, and tolerable duration of inundation following germination and early seedling establishment for native Fremont cottonwood and Goodding's willow, and non‐native tamarisk. Hydrological variables included peak flow timing, rate of flow recession following the peak, and duration of inundation. A one‐dimensional hydraulic model was applied to estimate stage‐discharge relationships along ~58 river kilometres. We then used HEC‐EFM to apply relationships between seedling ecology and streamflow to link hydrological dynamics with ecological response. We developed and validated HEC‐EFM based on an examination of seedling recruitment following an experimental flow release from Alamo Dam in spring 2006. The model predicted the largest area of potential recruitment for cottonwood (280–481 ha), with smaller areas predicted for willow (174–188 ha) and tamarisk (59–60 ha). Correlations between observed and predicted patches with successful seedling recruitment for areas within 40 m of the main channel ranged from 0.66 to 0.94. Finally, we examined arrays of hydrographs to identify which are most conducive to seedling recruitment along the river, given different combinations of peak flow, recession rate, and water volume released. Similar application of this model could be useful for informing reservoir management in the context of riparian restoration along other rivers facing similar challenges. [ABSTRACT FROM AUTHOR]

Riparian habitats provide refuge for unique plant and animal assemblages. Many riparian habitats in arid ecosystems have lost most of their vegetation and associated fauna, due to a reduction of their original extension by land transformation. Using a case study from the subtropical desert of Peru, we quantified avian richness, diversity and abundance of resident species in twelve sites with a varying degree of anthropogenic impact, using an anthropogenic index (A.I.) as a proxy of alteration of the original vegetation. Sites with lower values of A.I. were those with the highest percentage of riparian cover. We found that species richness was higher at sites with a higher percentage of riparian vegetation (low A.I.), although bird diversity did not differ between sites. Five bird species, mostly insectivorous passerines, showed higher abundances at sites with low A.I., suggesting that less riparian cover is associated with lower abundances of such species. Despite its conspicuous presence, the Slender‐billed Finch, an endemic species recorded at all sites, was found at lower abundances when riparian vegetation was scarcer. Only one species showed the opposite trend, the Rufous‐collared sparrow, a dietary generalist songbird, which was more abundant at sites with higher A.I. Other 20 species analysed showed no trend. Moreover, several species had few records precluding a formal statistical analysis. This study offers valuable data on the negative impact that the loss of native vegetation could have on riparian communities of subtropical ecosystems, for which no other long‐term data exist. The protection, management and restoration of riparian strips should be a priority for bird conservation in human‐modified environments, particularly for those in developing countries. Abstract in Spanish is available with online material. [ABSTRACT FROM AUTHOR]

Stream and river restoration practices have become common in many parts of the world. We ask the question whether such restorations improve freshwater biotic assemblages or functions over time, and if not, can general reasons be identified for such outcomes. We conducted a literature survey and review of studies in which different types of stream restorations were conducted and outcomes reported. These restoration types included culvert restoration; acid mine restoration or industrial pollutant restoration; urban stream restoration; dam removal, changes in dam operation, or fish passage structures; instream habitat modification; riparian restoration or woody material addition; channel restoration and multiple restorations. The streams ranged from headwater streams to large rivers, and the regions included North America, Europe, Australia and New Zealand, and a small number of sites in Asia and Africa. In this part of the review, we describe the methods used for the review and present reviews for the first three types of stream restorations. For culvert restorations, the small sample size and variable study design and biotic responses limited generalizing about temporal and spatial scale effects for that restoration type. The complex and often lengthy time to restore streams from acid mine drainage and industrial pollutants often resulted in positive biotic responses, but restored sites had reduced responses compared with reference sites. Most urban stream restorations had minimal or mixed improvements in biotic responses, with one mismatch in spatial scale evidenced by hydraulic structures used in a restoration unable to withstand peak discharge. [ABSTRACT FROM AUTHOR]