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Despite long‐standing knowledge of the benefits of riparian buffers for mitigating nonpoint source pollution, many streams are unprotected by buffers. Even landowners who understand ecological values of buffers mow riparian vegetation to the streambank. Do trends in rural riparian conditions reflect the development of riparian forest science? What motivates residential riparian management actions? Using high‐resolution orthoimagery, we quantified riparian conditions and trends between 1998 and 2015 in the rural upper Little Tennessee River basin in Macon County, North Carolina and explored how landowners view riparian zone management and riparian restoration programs. Buffer composition in 2015 was as follows: no buffer (32.5%), narrow (19.3%), forested (26.7%), shrub (7.2%), and intermediate (7.0%). Relative to 1998, the greatest decrease occurred in the no buffer class (−17.7%, 46 km) and the largest increases occurred in the shrub (+72.5%, 20 km) and narrow (12.6%, 14 km) classes. Forested buffer marginally increased. Semi‐structured interview data suggest that landowners prioritize recreational and scenic aspects of riparian buffers over ecological functions such as filtration and bank stabilization. Riparian restoration programs might be made more enticing to non‐adopters if outreach language appealed to landowner priorities, design elements demonstrated intentional management, and program managers highlighted areas where ecological goals and landowner values align. [ABSTRACT FROM AUTHOR]

Recent human population growth in North America's southern Appalachian Mountains has raised concerns about the effects of ex-urban development on its streams and their at-risk biota. The few studies to examine effects of land-use change in this region found that many headwater species require well-forested watersheds. Alasmidonta raveneliana is endemic to montane streams in North Carolina and Tennessee and during the past 20 years populations have declined alarmingly in several former strongholds. In 2015, we conducted surveys for A. raveneliana and quantified in-stream habitat and land-use at 25 current or historically occupied sites in the Nolichucky Drainage. We found that A. raveneliana populations were only detected at sites with well-forested watersheds and low proportions of fine substrates. Thin-sections revealed that A. raveneliana is fast-growing and short-lived (max age ~ 12 years) which may be an adaptation to unpredictable headwater streams. However, like many headwater specialists, A. raveneliana appears sensitive to changes in forest cover. Our results suggest that subtle changes in stream habitats linked to land-use change are a significant threat to the long-term survival of this species. Protection of forested headwaters and restoration of riparian zones appear to be the best strategies for conserving populations of this critically endangered freshwater mussel. [ABSTRACT FROM AUTHOR]

Agricultural land use, channel modifications, and riparian vegetation composition can affect instream denitrification by altering geomorphic features, such as sediment texture, organic matter, retention time, and hyporheic exchange. Stream and riparian restoration is widely implemented in agricultural watersheds to mitigate excess nutrient export to sensitive downstream waters; however, the cumulative impact of channel reconstruction and altered channel and nearstream morphology on nitrogen dynamics remains poorly understood. We measured denitrification enzyme activity (DEA) and environmental variables (e.g., water chemistry, sediment texture, and organic matter) in different geomorphic features in agriculturally influenced streams in North Carolina with varied channel and riparian zone characteristics. Our results indicate that denitrification is primarily influenced by increased transport of nitrate (NO3 -) to the streams in wetter months. Secondarily, structural factors, including riparian vegetation and stream geomorphology, impact denitrification by controlling the distribution of sediment texture and organic carbon. In the newly restored stream, we observed coarser streambed sediments and low sediment organic carbon, especially in scour pools constructed downstream from cross-vanes. Lower DEA was observed in restored pools (39.1 ng N g-1 dry mass h-1) compared to naturally occurring pools (70.7 to 278.1 ng N g-1 dry mass h-1). These results highlight the need for restoration strategies to be directed at increasing organic carbon and residence times through complex flowpaths (e.g., meanders, root wads, artificial woody debris dams). [ABSTRACT FROM AUTHOR]

While the influence of stream restoration on vertical and lateral hyporheic exchange has been documented, impacts on broader riparian zone hydrology have not been thoroughly investigated. We quantified riparian water table dynamics, hydraulic gradient, and groundwater flow paths and fluxes across a range of hydrologic conditions following natural channel design restoration (riparian regrading, in-channel cross-vane structure installation). Water table measurements were collected at least once per season for 2.5 years to capture water levels during baseflow conditions from networks of wells and piezometers at sites with different stream morphology (created riffle-cross-vane-scour pool complexes versus natural pools and riffles), restoration status (agricultural restored, unrestored, forested reference), and riparian characteristics (slope, soils, topography) in North Carolina, USA. The regraded riparian zone had higher near-stream water tables (< 0.5 m below ground surface) than the unrestored site. Riffle-cross-vane complexes induced a zone of low hydraulic gradient that spanned 30–40% of the riparian area, similar to groundwater dynamics near beaver dams. This effect persisted regardless of hydrologic condition (wet or dry) or scour pool status (functioning or filled-in). Riffles also promoted a lower near-stream hydraulic gradient at the forested site. Conversely, the influence of stream features on riparian groundwater was minimal at the unrestored site, where groundwater fluxes were controlled by hillslope inputs and riparian geomorphology. Overall, restoration enhanced stream-riparian zone hydrologic interaction beyond the immediate hyporheic zone. Our work stresses that cross-vanes, even when partially buried by sediments post-restoration, impact whole floodplain hydrology in a more significant way than shown by prior stream restoration studies. [ABSTRACT FROM AUTHOR]

Wildfire is a natural disturbance within many forest ecosystems and is rapidly becoming more frequent and severe because of the combination of historical fire suppression and climate change. In Southern Appalachian hardwood forests, there is a limited understanding of how salamander populations respond to wildfire, despite their high diversity and abundance in forest ecosystems. We expected populations of lungless, plethodontid salamanders to respond negatively to wildfire and the drier microhabitat conditions in burned habitat. We evaluated the effect of fire on 3 plethodontid salamander species (Blue Ridge two‐lined salamander [Eurycea wilderae], Ocoee salamander [Desmognathus ocoee], red‐legged salamander [Plethodon shermani]) with different life histories from 2017–2019 following a wildfire in a Southern Appalachian riparian forest in North Carolina, USA. We estimated differences in abundance, frequency of adults in the population, and terrestrial distribution in relation to streams between burned and reference riparian forest sites. Wildfire had negative effects on the abundance of semi‐aquatic species, but temporal patterns differed by species. Abundance of the Blue Ridge two‐lined salamander was lower in burn sites than reference sites immediately after fire, followed by a gradual convergence towards reference‐site densities. Conversely, Ocoee salamanders had a time‐lagged response, where we observed significantly lower densities in burn sites relative to reference sites for only 2 years after fire. We did not observe strong responses of red‐legged salamander abundance to fire. There were no consistent patterns in how the percentage of adults in reference or burn sites differed over time, suggesting that population responses to burn vary by species. Finally, we observed adults of all species and juveniles of semi‐aquatic species farther from streams in burn sites. Our findings suggest plethodontid salamander communities may tolerate riparian wildfires, although longer‐term studies are required to understand how long it takes for patterns of population size structure and habitat use to converge with those in unburned reference sites. [ABSTRACT FROM AUTHOR]

The extensive agricultural feedlot operations in the Neuse River Watershed (NRW) in North Carolina result in high nutrient loading, particularly of ammonium (NH4+). In September 2018, Hurricane Florence devastated large portions of the NRW, creating a unique opportunity to study the impact of such hydrological events on the biogeochemistry of riverine and riparian sediments. The high NH4+ concentrations, naturally acidic conditions, and elevated levels of ferric iron [Fe(III)] in Neuse River sediments and soils provide an ideal environment for Acidimicrobium sp. A6 (referred to hereon as A6), a bacterium capable of conducting the Feammox process in which NH4+ is oxidized while iron is reduced. A6 was observed in all sediment samples obtained from the Neuse River, and it is therefore predicted that this process may be an important mechanism for NH4+ removal in this river system. Incubations of NRW samples indicate that the NH4+ oxidation potential via the Feammox process in the NRW is comparable with aerobic NH4+ oxidation by heterotrophic microorganisms. Given the high demand for Fe(III) by the Feammox process, it has been unclear how such a process may occur in sedimentary environments where ferric iron [Fe(III)] might be depleted. The results presented here show that a major hydrologic storm event can result in an increase in Fe(III) and in an increase in the abundance of Fe-reducing bacteria, including Acidimicrobium sp. A6. These findings indicate that major hydrologic storm events may, via the delivery of Fe(III), be capable of enhancing Feammox activity in riverine sediments that favor the Feammox process. [ABSTRACT FROM AUTHOR]

How much stream temperatures increase within riparian canopy openings and whether stream temperatures cool downstream of these openings both have important policy implications. Past studies of stream cooling downstream of riparian openings have found mixed results including rapid, slow, and no cooling. We collected longitudinal profiles of stream temperatures above, within, and below riparian forest openings along stream segments within otherwise forested riparian conditions to evaluate how sensitivity of stream temperatures to riparian conditions varied across landscape factors. We conducted these temperature surveys across openings in 12 wadeable streams within and near the Upper Little Tennessee River Basin in western North Carolina and northeastern Georgia. Basin areas ranged from 74 to 6,913 ha, and bankfull channel widths varied from 3.4 to 16.4 m. Stream temperatures were collected every 15 min using HOBO® data loggers for 2 weeks in each stream, repeated later in summer in some streams. Reference temperatures were highest in stream reaches at low elevations and with large drainage areas. Stream temperature increases in the middle of riparian gaps were highest when streams drained small high‐elevation watersheds, and increases at the end of openings were highest when the opening length was large relative to watershed size. Downstream from openings, cooling rates were greatest in small, high‐elevation headwater streams and also increased with larger increases in canopy cover. Stream segments that warmed the most within openings also featured higher cooling rates downstream. The data show that stream temperature sensitivity to canopy change is highly dependent on network position and watershed size. A better understanding of stream temperature responses to riparian vegetation may be useful to land managers and landowners prioritizing riparian forest restoration. [ABSTRACT FROM AUTHOR]

The article analyzes the long-term effectiveness of riparian buffer zones designed to reduce groundwater nitrate from agriculture. Topics include the testing of vegetation types including trees, switchgrass, fescue, native plants, and a control buffer; the impact of buffer types and widths on dissolved organic carbon (DOC) as well as groundwater nitrates; and the results of the study in the middle coastal plain of North Carolina.

The riparian ecosystem management model ( REMM) was field tested using five years (2005-2009) of measured hydrologic and water quality data on a riparian buffer located in the Tar-Pamlico River Basin, North Carolina. The buffer site received NO3-N loading from an agricultural field that was fertilized with inorganic fertilizer. Field results showed the buffer reduced groundwater NO3-N concentration moving to the stream over a five-year period. REMM was calibrated hydrologically using daily field-measured water table depths ( WTDs), and with monthly NO3-N concentrations in groundwater wells. Results showed simulated WTDs and NO3-N concentrations in good agreement with measured values. The mean absolute error and Willmott's index of agreement for WTDs varied from 13-45 cm and 0.72-0.92, respectively, while the root mean square error and Willmott's index of agreement for NO3-N concentrations ranged from 1.04-5.92 mg/l and 0.1-0.86, respectively, over the five-year period. REMM predicted plant nitrogen (N) uptake and denitrification were within ranges reported in other riparian buffer field studies. The calibrated and validated REMM was used to simulate 33 years of buffer performance at the site. Results showed that on average the buffer reduced NO3-N concentrations from 12 mg/l at the field edge to 0.7 mg/l at the stream edge over the simulation period, while the total N and NO3-N load reductions from the field edge to the stream were 77 and 82%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: There is little understanding about the role eastern US forested headwater riparian areas play in protecting aquatic habitats and water quality from impacts of side slope forest harvest. To better understand this important riparian area function, we selected three sites from management units with a 2-age regeneration silvicultural prescription located on the Nantahala National Forest, North Carolina, USA. Each site was harvested and a riparian buffer was left uncut along the stream. Buffer widths were 10m and 30m; we included a 0m buffer to experimentally determine nutrient and riparian zone responses to forest cutting under extreme conditions. A fourth site was selected to serve as an uncut reference. Transects were established perpendicular to a 200m stream reach, from streamside to 50m upslope for intensive study. Forest cutting increased extractable NO3 − concentrations increased only in harvested areas, on all sites; increases were greater in sites with narrow riparian buffers. Stream water NO3 concentration increased significantly following site harvest only on the 0m buffer site. Dissolved organic C and N did not respond to harvesting in either soil solution or stream samples. Our results suggest that riparian buffers are effective in removing NO− concentrations increased only in harvested areas, on all sites; increases were greater in sites with narrow riparian buffers. Stream water NO3 − concentration increased significantly following site harvest only on the 0m buffer site. Dissolved organic C and N did not respond to harvesting in either soil solution or stream samples. Our results suggest that riparian buffers are effective in removing NO3 − from soil solution prior to its entering the stream. [Copyright &y& Elsevier]

Tidal freshwater zones (TFZ) of coastal rivers link terrestrial watersheds to the ocean and are characterized by large, regularly inundated riparian zones. We investigated the effect of riparian denitrification on nitrogen flux in the TFZ Newport River, North Carolina (U.S.A.) by developing an empirical model of denitrification and parameterizing it using measured denitrification rates, sediment oxidation-reduction potential dynamics, and riparian topography. Denitrification rates were measured monthly in laboratory-incubated sediment cores by using a membrane inlet mass spectrometer to assess net water-borne N2 flux from the cores. Annual average rates of denitrification in three intertidal riparian habitats, emergent marsh, mudflat, and hardwood forest, were 1864, 1956, and 2018 μg m−2 h−1, respectively. Laboratory experiments and in-situ monitoring revealed that the temporal lag between tidal inundation and reduced, denitrifying conditions was 4–5 h. Field measurements and remotely sensed data showed that the inundated surface area during high tide was three times greater than that at low tide. By combining data on denitrification, oxidation-reduction potential, and topography, the model predicted that the daily denitrification flux constituted 2–15% of the daily riverine nitrate flux during most of the year and >100% during low discharge periods. Current regional and global nitrogen budgets thus may overestimate nitrogen delivery to the ocean by not accounting for the TFZ denitrification. [ABSTRACT FROM AUTHOR]

Examines spatial variability of phosphorus sorption and related soil properties in Riparian wetlands in North Carolina. Effects of spatial autocorrelation; Measurement of bulk density, moisture, pH, soil organic matter, texture, iron and the phosphorus sorption index; Geostatistical analyses.

Water-quality and hydrologic information were collected along ground-water flow paths from two well-drained and two poorly drained Coastal Plain settings in North Carolina to evaluate the relative effectiveness of riparian buffers in reducing discharge of nitrate to streams. At one well-drained site with a 100 m buffer, little or no effect was detected on surface-water quality by discharging ground water because extensive woody vegetation in the buffer was able to take up not only most nitrate, but also most ground water before discharging to the stream during the growing season (March-October). At the second well-drained site, ground water discharging to the stream from the side with a buffer contained about 2 mg/L of nitrate-nitrogen after passing through the bed of the stream compared to 6 mg/L in ground water discharging from the side with no buffer. In the poorly drained settings, nitrate in ground water decreased from about 6 mg/L in the recharge area to less than 0.02 mg/L downgradient from the riparian buffer. Ground water discharging from the side with no buffer contained 0.83 mg/L. Riparian buffers appear effective in reducing nitrate in ground water discharging to Coastal Plain streams. [ABSTRACT FROM AUTHOR]

The article focuses on the importance of restoring and reforesting headwater riparian zones for increasing carbon storage and improving water quality. It examines the potential of additional carbon storage in the North Carolina Coastal Plain stream network based on the distribution of riparian zone cover/condition classes in sampled headwater riparian reaches.

The floodplains of the Southeast's stream network once hosted immense brakes of rivercane (Arundinaria gigantea), a disturbance-dependent native bamboo with both cultural and ecological significance. Ecologically, rivercane alters its local environments, boosts biodiversity and biomass, and protects streambanks from erosion and storm damage. Indigenous peoples of the Southeast have used rivercane for millennia, for material and cultural purposes, and formerly maintained its health and extent through harvesting and fire. Settler-colonial incursions largely destroyed rivercane, through the more intense disturbance of different land management practices, and brakes now exist mainly in relatively small areas. While numerous rivercane restoration projects are in process throughout its natural range, no comprehensive inventory of living rivercane exists. In this paper, we present both human context and the results of LiDAR analysis that identifies canebrakes based on the physical characteristics of the plant and brake. In our study area on the Little Tennessee River in western North Carolina, we found rivercane on about 9 percent of the floodplain area, based on QL1 LiDAR data available from the state of North Carolina. The technique can be applied in any part of rivercane's range, and the resulting inventory used in support of both cultural and ecological goals. [ABSTRACT FROM AUTHOR]

ABSTRACT: Irrigation of anaerobic swine lagoon effluent onto cattle-grazed grass pastures represents a common waste treatment method in the Coastal Plain of North Carolina. However, such treatment strategies can result in high nitrate (NO[sub 3]) concentrations in the shallow groundwater beneath spray fields, and ultimately surface waters receiving groundwater discharge if application rates exceed crop and animal removal. This study was conducted to determine NO[sub 3] accumulation and movement in the spray fields and riparian zone on a swine farm in eastern North Carolina, as well as effects of effluent irrigation on streams recharged by shallow groundwater flow. Increases in the NO[sub 3] concentration of receiving streams occurred over the farm, suggesting that some NO[sub 3] was reaching surface waters. Despite evidence of denitrification losses in riparian areas, the riparian zone did not fully protect the receiving streams from high concentrations of NO[sub 3] in the groundwater. [ABSTRACT FROM AUTHOR]

Riparian revegetation, such as planting woody seedlings or live stakes, is a nearly ubiquitous component of stream restoration projects in the United States. Though evaluations of restoration success usually focus on in-stream ecosystems, in order to understand the full impacts of restoration the effects on riparian ecosystems themselves must be considered. We examined the effects of stream restoration revegetation measures on riparian ecosystems of headwater mountain streams in forested watersheds by comparing riparian vegetation structure and composition at reference, restored, and degraded sites on nine streams. According to mixed model analysis of variance (ANOVA), there was a significant effect of site treatment on riparian species richness, basal area, and canopy cover, but no effect on stem density. Vegetation characteristics at restored sites differed from those of reference sites according to all metrics (i.e. basal area, canopy cover, and species composition) except species richness and stem density. Restored and degraded sites were structurally similar, with some overlap in species composition. Restored sites were dominated by Salix sericea and Cornus amomum (species commonly planted for revegetation) and a suite of disturbance-adapted species also dominant at degraded sites. Differences between reference and restored sites might be due to the young age of restored sites (average 4 years since restoration), to reassembly of degraded site species composition at restored sites, or to the creation of a novel anthropogenic ecosystem on these headwater streams. Additional research is needed to determine if this anthropogenic riparian community type persists as a resilient novel ecosystem and provides valued riparian functions. [ABSTRACT FROM AUTHOR]

Abstract: The appropriate management of streamside forests and use of riparian strips is poorly resolved for many systems because of a lack of understanding of the extent to which riparian forests function as environmental buffers for aquatic species versus core (essential) habitat for semi-aquatic and terrestrial species. We studied streamside forests in western North Carolina and eastern Tennessee, USA, to help delineate their functional value for plethodontid salamanders. We established 30m×40m plots at 17 sites (823–1716m in elevation) in unmanaged forests with closed canopies. Plots contained a portion of a seep or first-order stream along one edge and typically extended 36–38m into the adjoining forest. We examined use of stream and streamside habitats based on captures during area-constrained searches of cover objects. We observed 6423 plethodontid salamanders belonging to 7 terrestrial-breeding and 12 aquatic-breeding species. Terrestrial-breeders (primarily Plethodon spp.) comprised 37% of terrestrial specimens and were more abundant at higher elevations. Aquatic-breeders (primarily Desmognathus spp.) increased their proportionate use of terrestrial habitat, but declined in overall abundance with elevation. Catches of aquatic-breeders were greatest within 8m of aquatic habitats (49% of total terrestrial catch of aquatic-breeders), particularly at low elevation sites. The terrestrial zone provided core habitat for one terrestrial-breeder (D. wrighti) and six semi-aquatic species (Desmognathus spp., Gyrinophilus porphyriticus and Eurycea wilderae) that were broadly distributed throughout plots, and acted as an aquatic buffer for four highly aquatic species (Desmognathus spp.). The remaining species were terrestrial-breeders (Plethodon spp.) that were evenly distributed across plots, suggesting that riparian strips would function as important source populations for recolonization following timbering on adjoining land. Because of the vulnerability of plethodontid salamanders to edge effects, effective management of southern Appalachian streamside habitats may require the addition of a terrestrial buffer to protect terrestrial core habitat that immediately adjoins streams and seeps. [Copyright &y& Elsevier]

We studied the habitat characteristics of Spiraea virginiana Britton (Virginia spiraea), a federally threatened riparian shrub, along eight rivers in western North Carolina. Comparisons between plots with and without S. virginiana revealed that S. virginiana plots were on steep, south-facing slopes and had a higher percentage of large substrate, lower herbaceous and vine cover, higher non- S. virginiana shrub density, lower tree influence, and higher visible sky than control plots. When relating these habitat attributes to the presence/absence of S. virginiana using conditional logistic regression, only substrate size and non- S. virginiana shrub density had significant effects on S. virginiana presence. Principal components analysis (PCA) of all plots ( S. virginiana and control) found S. virginiana plots separating from controls that had higher vine and herb cover and lower non- S. virginiana shrub density and slope. Spiraea virginiana plots at the Cheoah River separated from other sites by having greater substrate size and tree influence, and lower visible sky and herb cover. Regression analysis between S. virginiana volume and PCA axes (of plots with S. virginiana only) indicated that volume increased with increasing small substrate, visible sky and non- S. virginiana shrub density, but decreased with increasing tree influence, herb and vine cover, and decreasing slope. Spiraea virginiana restoration efforts should focus on habitats with the attributes described in this study to favor its presence. To ensure S. virginiana vigor, competition from trees, non- S. virginiana shrubs, vines and herbs, especially aggressive nonnative species, should be reduced. [ABSTRACT FROM AUTHOR]

Riparian buffers have been used for many years as a best management practice to decrease the effects of nonpoint pollution from watersheds. The NC Conservation Reserve Enhancement Program ( NC CREP) has established buffers to treat groundwater nitrate-nitrogen ( NO3−-N) from agricultural sources in multiple river basins. A maturing 46 m wide riparian buffer enrolled in NC CREP was studied to determine its effectiveness in reducing groundwater NO3−-N concentrations from a cattle pasture fertilized with poultry litter. Three monitoring blocks that included groundwater quality wells, water table wells, and soil redox probes, were established in the buffer. NO3−-N concentrations decreased significantly across the buffer in all of the monitoring blocks with mean reductions of 76-92%. Many biological processes, including denitrification and plant uptake, may have been responsible for the observed NO3−-N reductions but could not be differentiated in this study. However, mean reductions in Cl− concentrations ranged from 48-65% through the blocks, which indicated that dilution was an important factor in observed NO3−-N reductions. These findings should be carefully considered for future buffer enrollments when assigning nitrogen removal credits. [ABSTRACT FROM AUTHOR]

Freshwater communities are threatened by the conversion of natural landscapes for urban and agricultural purposes. Changes to land use may disrupt stream nutrient and geomorphological processes and reduce water quality, increase sedimentation, and decrease habitat heterogeneity eventually leading to species loss and decreases in ecosystem productivity. Endemic species are frequently at greater risk of habitat‐mediated fragmentation and extirpation due to their constrained distributions.The Kanawha darter (Etheostoma kanawhae) is an understudied fish endemic to the New River Drainage in North Carolina and Virginia, USA. To investigate the potential effect(s) of land‐use change on Kanawha darters, naïve occupancy was modelled using instream habitat characteristics and upstream forest cover.Generalized linear models revealed that instream habitat and forest cover are reliable predictors of Kanawha darter site occupancy. Specifically, models demonstrated that occupancy increased in reaches with reduced stream width, velocity, and bedrock substrate but higher concentrations of coarse woody material. Kanawha darter occupancy was also positively associated with the extent of forest cover in upstream catchments.Although Kanawha darters are not currently considered imperilled, most populations occurred in isolated reaches separated by large sections of unoccupied habitat. Continuing ex‐urban development in riparian zones is likely to be the primary threat to Kanawha darters and other endemic species in this catchment. Resource managers and stakeholders should preserve forest cover in headwaters and occupied tributaries and protect or restore riparian zones along the main‐stem South and North Forks of the New River to preserve high‐quality habitat and enhance connectivity among isolated Kanawha darter populations.As human populations in montane regions continue to grow, there is a need to understand how land‐use change affects endemic freshwater species. This study further supports the importance of retaining forest cover as an effective strategy for protecting and restoring populations of endemic fishes in high‐gradient streams. [ABSTRACT FROM AUTHOR]

Riparian buffers, the strips of vegetation along banks of rivers and streams, have been proposed as a key instrument to protect water quality in the United States. Riparian buffers impose a restriction on the use of private property limiting harvest and development, but buffers can also provide for aesthetic and recreational benefits that may accrue to property owners. With data from the Neuse River Basin in North Carolina, this study attempts to provide empirical evidence on the effect of a mandatory buffer rule on the value of riparian properties. Spatial autoregressive hedonic models are estimated within a quasi-experimental framework using the imposition of the buffer rule as the treatment and nonriparian properties as a control group. Results indicate that a riparian property generally commands a high premium. We find no evidence, however, that the mandatory buffer rule has had a significant impact on riparian property values when compared with the control group. [ABSTRACT FROM AUTHOR]

Shiflett, S.A. and Backstrom, J.T., 2023. Impacts of Hurricane Isaias (2020) on geomorphology and vegetation communities of natural and planted dunes in North Carolina. Journal of Coastal Research, 39(4), 587–609. Charlotte (North Carolina), ISSN 0749-0208. Coastal dunes serve a crucial role in reducing inland flooding, slowing shoreline erosion, and acting as a physical barrier to protect developed coastal communities from storm-related impacts. Dunes also provide critical habitat for several shoreline species. High magnitude storms such as hurricanes and nor'easters can have profound and long-lasting impacts on low-lying coastal areas, ranging from minor and temporary beach erosion to complete devastation of entire barrier island systems. This study documents direct impacts of Category 1 Hurricane Isaias (2020), one of the strongest tropical storms to directly hit the region, on coastal dune geomorphology and vegetation of Holden Beach, a south-facing barrier island located in SE North Carolina. Impacts were investigated using a combination of pre- and poststorm real-time kinematic dune profiles, vegetation cover and type transects, prestorm high-resolution drone imagery, and poststorm National Oceanic and Atmospheric Administration aerial imagery. Dominant geomorphological impacts included a variety of depositional and erosional effects, which were more prominent along artificially renourished and planted coastal segments compared to adjacent natural dune systems. Geomorphological changes subsequently reduced poststorm dune vegetation density. Yet, reduced impact on vegetation species abundance (i.e. stem density) was evident at a wider, stabilized dune area, which lacked human management, compared with narrower, less mature, and actively managed (i.e. fenced and/or planted) dune areas. Dune grasses were more resilient to Hurricane Isaias than forbs; however, several volunteer forb species, noted for dune stabilization abilities, were present at unmanaged dunes. Results indicate planting a diverse palette of native coastal species, which when co-occurring fill a variety of functional roles, will increase dune resilience to tropical storms. This study provides important insights into optimizing dune management strategies for developed barrier islands and other low-lying temperate coastal regions, which may be susceptible to ongoing sea-level rise and high-energy storm events. [ABSTRACT FROM AUTHOR]

One hundred five species of lichenized and allied fungi are reported from recent and historical collections made in the Mitchell Mill State Natural Area in northeastern Wake County, North Carolina, USA. Mitchell Mill is unique among granitic flatrock communities in the southeastern United States by having riparian elements from the Little River, which flows directly over the flatrock, supporting semi-aquatic lichen communities along creek edges represented by species in Dermatocarpon, Verrucaria, and Lichinales. Recently described or renamed species Cladonia ignatii, Lecanora provertula and Phyllopsora isidiosa were found in recent collections. Compared to historical records, 38 taxa including five of six species of large cyanolichen were not found in recent visits, indicating a loss of diversity over the past 100 years, likely due to human activities. [ABSTRACT FROM AUTHOR]

Understanding wetland hydrogeology is important as it is coupled to internal geochemical and biotic processes that ultimately determine the fate of potential contaminant inputs. Therefore, there is a need to quantitatively understand the complex hydrogeology of wetlands. The main objective of this study was to improve understanding of saturated groundwater flow in a forested riparian wetland located on a golf course in the Lower Pee Dee River Basin in South Carolina, USA. Field observations that characterize subsurface wetland flow critical to solute transport originating from storm-generated runoff are presented. Monitoring wells were installed, and slug tests were performed to measure permeabilities of the wetland soil. A field-scale bromide tracer experiment was conducted to mimic the periodic loading of nutrients caused by storm runoff. This experiment provided spatial and temporal data on solute transport that were analyzed to determine travel times in the wetland. Furthermore, a 3-D numerical, steady-state flow model (MODFLOW) was developed to simulate subsurface flow in the wetland. A particle tracking model was subsequently used to calculate solute travel times from the wetland inlet to the outlet based on flow modeling results. It was evident that observed tracer breakthrough times were not typical of these measured wetland soil matrix conductivity values. Based on surface water sampling results at the wetland outlet, tracer arrival time was about 9 h after the injection of the tracer. These results implied an apparent mean K value of 2,050 m/day, which is 152 times larger than the mean of the measured values using slug tests (13.4 m/day). Modeling efforts clearly demonstrated this implied preferential flow behavior; particle travel times resulting from the calibrated flow model were in the order of hundreds of days, while actual travel times in the wetland were in the order of hours to a few days. This significant difference in travel times was attributed to the presence of macropores in the form of dead root channels and cavities forming a pipe-flow network. The analyses presented in this study resulted in an estimate of the ratio of matrix permeability to matrix plus macropore permeability of approximately 1/150. Eventually, the tracer test and resulting travel times between various points in the wetland were critical to understanding the true wetland flow dynamics. The final conceptual model of the hydraulic properties of the wetland soils comprised a low permeability matrix containing a web of high K macropores. Simulation of tracer transport in this system was possible using a flow model with significantly elevated K values. [ABSTRACT FROM AUTHOR]

Streams in urbanizing watersheds are threatened by economic development that can lead to excessive sediment erosion and surface runoff. These anthropogenic stressors diminish valuable ecosystem services and result in pervasive degradation commonly referred to as "urban stream syndrome." Understanding how the public perceives and values improvements in stream conditions is necessary to support efforts to quantify the economic benefits of water quality improvements. We develop an ecological production framework that translates measurable indicators of stream water quality into ecological endpoints. Our interdisciplinary approach integrates a predictive hierarchical water quality model that is well suited for sparse data environments, an expert elicitation that translates measurable water quality indicators into ecological endpoints that focus group participants identified as most relevant, and a stated preference survey that elicits the public's willingness to pay for changes in these endpoints. To illustrate our methods, we develop an application to the Upper Neuse River Watershed located in the rapidly developing Triangle region of North Carolina (the United States). Our results suggest, for example, that residents are willing to pay roughly $127 per household and $54 million per year in aggregate (2021 US$) for water quality improvements resulting from a stylized intervention that increases stream bank canopy cover by 25% and decreases runoff from impervious surfaces, leading to improvements in water quality and ecological endpoints for local streams. Although the three components of our analysis are conducted with data from North Carolina, we discuss how our findings are generalizable to urban and urbanizing areas across the larger Piedmont ecoregion of the Eastern United States. [ABSTRACT FROM AUTHOR]

Hydric soil development of riparian wetlands is primarily influenced by the hydrologic connection between the floodplains and the stream channel. Often, the goal of riparian restoration is to revitalize this connectivity through a restructuring of the stream channel and the floodplain; however, the effects of this restructuring on the physical and spatial characteristics of soil properties are rarely considered. The objective of this study was to quantify the impacts of restoration efforts on the spatial characteristics of soil properties by means of a pre- and post-restoration comparison. We determined that the spatial patterns of soil organic matter (SOM) and exchangeable phosphorus (Pex) appeared less variable in the years following restoration than in the years before restoration. Mean SOM significantly decreased after restoration, whereas mean Pex significantly increased. The spatial characteristics and mean concentrations of NO2-NO3 did not differ much between sampling dates. The loss of this spatial patterning in SOM and Pex and the decrease in SOM pools may represent negative impacts of restoration on important ecosystem characteristics. This study demonstrates that soil properties and spatial patterns can be negatively affected by restoration activities potentially hindering ecosystem development and function. [ABSTRACT FROM AUTHOR]

Background & aims: Plants may have dissimilar effects on ecosystem processes because they possess different attributes. Given increasing biodiversity losses, it is important to understand which plant traits are key drivers of ecosystem functions. To address this question, we studied the response of two ecosystem functions that remove nitrogen (N) from wetland soils, the accumulation of N in plant biomass and denitrification potential (DNP), to variation in plant trait composition. Methods: Our experiment manipulated plant composition in a riparian wetland. We determined relative importance of plant traits and environmental variables as predictors of each ecosystem function. Results: We demonstrate that Water Use Efficiency (WUE) had a strong negative effect on biomass N. Root porosity and belowground biomass were negatively correlated with DNP. Trait ordination indicated that WUE was largely orthogonal to traits that maximized DNP. Conclusions: These results indicate that plant species with different trait values are required to maintain multiple ecosystem functions, and provide a more mechanistic, trait-based link between the recent findings that higher biodiversity is necessary for multi-functionality. While we selected plant traits based on ecological theory, several of the plant traits were not good predictors of each ecosystem function suggesting the ecological theory linking traits to function is incomplete and requires strengthening. [ABSTRACT FROM AUTHOR]

Many species of wildlife depend on riparian habitats for various life-history functions (e.g., breeding, foraging, overwintering). Although this unique habitat is critical for many species, delineations of riparian zones and buffers for various taxa are lacking. Typically when buffer zones are determined to mitigate edge effects, they are based on criteria that protect aquatic resources alone and do not consider impacts to wildlife and other terrestrial resources. Using two different survey methods (area-constrained daytime searches and nighttime visual encounter searches), we estimated core terrestrial habitat and buffer widths for stream-breeding salamanders in southern Appalachian streams from May to August 2004. A core terrestrial habitat of 27.0 m encompassed 95% of the salamander assemblage (four species of stream plethodontids), and an additional 50 m (to buffer edge effects) yielded a total buffer of 77.0 m. When each species of the assemblage was analyzed separately, the maximum core terrestrial habitat needed for the Blue Ridge two-lined salamander (Eurycea wilderae), a dominant member and the farthest-ranging species from the stream, was 42.6 m. Thus, we recommend an overall buffer width of 92.6 m in southern Appalachian streams. To protect stream amphibians and other wildlife dependent on riparian areas, land managers and policy makers must consider conserving more than aquatic resources alone. Developing core terrestrial habitat estimates and buffer zone widths for wildlife populations is a critical first step in the conservation of many semiaquatic organisms and protecting biodiversity.

Maintaining ground cover of forages may reduce the export of nitrogen (N) from pastures. The objective of this work was to determine the effect of ground cover on N export from pastured riparian areas receiving simulated rainfall. Plots were established on two adjacent sites in the North Carolina Piedmont: one of 10% slope with Appling sandy loam soils and a second of 20% slope with Wedowee sandy loam soils. Both sites had existing mixed tall fescue (Festuca arundinacea Schreb.)-dallisgrass (Paspalum dilatatum Poir.) vegetation. Forage stands were modified to represent a range of ground cover levels: 0, 45, 70, and 95% (bare ground, low, medium, and high cover, respectively), and amended with beef steer (Bos taurus) feces and urine (approximately 200 kg N ha-1). For all rain events combined, mean nitrate N export was greatest from bare ground and was reduced by 34% at low cover, which did not differ from high cover. Mean ammonium N export was slightly elevated (approximately 1.37 kg N ha-1) in months when manures were applied and negligible (<0.02 kg N ha-1) in all other months. For all rain events combined, mean export of total N was greatest from bare ground and was reduced by at least 85% at all other cover levels. Whereas site did not impact N export, results indicated that cover and time of rainfall following manure deposition are important determinants of the impact of riparian grazing.

Maintaining pasture ground cover is important in preventing environmental degradation of grasslands and associated riparian areas. The objective of this work was to determine the effect of ground cover on sediment and P export from pastured riparian areas under simulated rainfall events. Plots were established on two sites in the North Carolina Piedmont: a 10% slope with Appling sandy loam soils (fine, kaolinitic, thermic Typic Kanhapludults) and a 20% slope with Wedowee sandy loam soils (fine, kaolinitic, thermic Typic Kanhapludults), both with mixed tall fescue (Festuca arundinacea Schreb.)-dallisgrass (Paspalum dilatatum Poir.) vegetation. Existing forage stands were modified to represent a range of ground cover levels: 0, 45, 70, and 95% (bare ground, low, medium, and high cover, respectively), and amended with beef steer (Bos taurus) feces and urine (about 10 kg P ha(-1)). Mean runoff volume from bare ground was generally twice that observed from low, medium, and high levels of cover, which were similar. For all rainfall events combined, export of dissolved reactive P was greatest (P < 0.1) at bare ground and was reduced 31% at low cover, which did not differ from medium or high cover. Mean total Kjeldahl P export was greater (P < 0.001) from bare ground than from other cover levels. Results indicate that riparian bare areas can contribute substantial sediment (>215 kg ha(-1)) and P (0.7 kg P ha(-1)) to surface waters during heavy rainfall, whereas export may be reduced equally well by low cover (45%) as by high cover.

• Clearcut harvest with buffers did not negatively impact macroinvertebrates. • More sensitive species were collected in one harvested watershed. • Sites with more stream flow and organic carbon had more sensitive species. • More sensitive species were present at sites with large pine trees. Forest disturbances have significant effects on water quality and quantity, river geomorphology, and the ecology of receiving waterbodies. Riparian forests provide numerous functions for aquatic communities including retaining fine sediments and nutrients, controlling water temperature, and providing food sources and habitat for aquatic organisms. Forestry Best Management Practices (BMPs) use riparian forests as buffers to mitigate potential sources of disturbance to aquatic ecosystems from forest management. The objective of this study was to quantify the impacts of timber harvest on stream macroinvertebrates in the Piedmont region. We assessed the changes in macroinvertebrate communities and identified their relationships with specific hydrologic and water quality parameters. We used a paired watershed approach to quantify the response of watershed hydrology and water quality to clearcut forest harvesting with the use of BMPs in the Hill Demonstration Forest and Umstead Research Farm in central North Carolina. We sampled macroinvertebrates and monitored water quality in the first-order streams, and surveyed vegetation within riparian zones one year preharvest (2010) and four years postharvest (2011–2014). We found more sensitive species (indicated by biotic index classifications), scrapers, and Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa from the harvested watershed than in the reference watershed at the Umstead Research Farm site. No differences were detected between the reference and treatment watersheds at the Hill Demonstration Forest site. More sensitive species were present in watersheds with the highest pine basal area and in-stream total organic carbon (TOC) loads. More scrapers were present in watersheds with low hardwood basal area, high stream flow, and more vines. EPT abundance was higher in watersheds with high stream flow, large pine trees, and thick leaf litter layer. EPT abundance was lower in watersheds with large hardwood trees and high TOC loads. Overall, sensitive species, scrapers, and EPT abundance were lower in the Umstead Research Farm reference watershed than in any other watershed. We conclude that, in contrast to similar studies in the region, clearcut harvesting with the use of BMPs did not cause detectable negative effects on macroinvertebrate communities. Moreover, water quality as determined by macroinvertebrates may even be improved in some cases following clearcutting. This study provides a better understanding of how macroinvertebrate communities in Piedmont streams change after harvesting and what watershed characteristics may be driving these changes. This information is useful in characterizing macroinvertebrates in headwaters in the Piedmont, and helps land managers protect aquatic resources across the region. [ABSTRACT FROM AUTHOR]

This paired watershed study tested the effects of timber harvest on water quantity and quality in the North Carolina Piedmont physiographic region, four headwater watersheds at Hill Demonstration Forest (HF1, HF2, HFW1, and HFW2) and two at Umstead Research Farm (UF1 and UF2) were continuously monitored for discharge and water quality from 2007 to 2013. The HF1 and UF1 watersheds were dearcut (treatment), leaving a 15.2-m vegetated riparian buffer around the streams to protect water quality as described in the North Carolina Neuse River Basin Riparian Buffer Rule. HF2 and UF2 were uncut and used as reference watersheds. Merchantable timber was selectively removed from the riparian buffer, reducing tree basal area by 27% in HF1 and 48% in UF1. HF1 and HF2 were nested within HFW1; thus, HFW1 was considered a partial cut where 33% of the watershed area was harvested, and HFW2 was the reference. We found that discharge in treatment watersheds increased dramatically, averaging 240% in HF1 and 200% in UF1 and 40% in HFW1 during the postharvest period, 2011-2013. Total suspended sediment export in the treatment watersheds also increased significantly in HF1 after harvest, probably due to the increase of discharge and movement of in-channel legacy sediment. Stormflow peak nitrate reached its maximum concentration during the first 2 years after harvest in the treatment watersheds and then declined, corresponding to the rapid regrowth of woody ond herbaceous plants in the riparian buffer and uplands. We found that 36% of the UF1 streambank trees were blown down but did not cause a measurable increase in mean daily stormflow total suspended sediment concentration. Most buffer tree blowdown occurred during the first few years after a harvest. Bioclassification of benthic macroinvertebrates indicated that stream water quality remained good/fair to excellent in the treatment watersheds after the harvest. We conclude that the temporary increases in discharge were relatively large for the Piedmont region compared with those for other regions in the southeastern United States. However, the increases in channel sediment transport and nutrient exports associated with the hydrologic change did not have a measurable impact on the indicators of aquatic invertebrate community health or bioclassification rankings. [ABSTRACT FROM AUTHOR]

This study evaluates the effects of urban land use on stream channels and riparian ground-water levels along low-order Inner Coastal Plain streams in North Carolina. Six sites with stream catchments of similar size (1.19-3.46 km2) within the Tar River Basin were selected across an urban land use gradient, as quantified by a range of catchment total impervious area (TIA; 3.8-36.7%). Stream stage and ground-water levels within three floodplain monitoring wells were measured manually and using pressure transducers from May 2006-June 2007. Channel incision ratio (CIR), the ratio of bank height to bankfull height, was also measured at each monitoring site and along stream reaches within the study area (12 urban and 12 rural sites). Riparian ground-water levels were inversely related to catchment TIA (%). As TIA (%) and stormwater runoff increased, the degree of stream channel incision increased and riparian ground-water tables declined. In urban floodplains (>15% TIA), the median ground-water level was 0.84 m deeper than for the rural settings (<15% TIA). This has resulted in a shift to drier conditions in the urban riparian zones, particularly during the summer months. CIR was found to be a reliable surface indicator of “riparian hydrologic drought” in these settings. [ABSTRACT FROM AUTHOR]

1. We characterised aquatic and terrestrial invertebrate drift in six south-western North Carolina streams and their implications for trout production. Streams of this region typically have low standing stock and production of trout because of low benthic productivity. However, little is known about the contribution of terrestrial invertebrates entering drift, the factors that affect these inputs (including season, diel period and riparian cover type), or the energetic contribution of drift to trout. 2. Eight sites were sampled in streams with four riparian cover types. Drift samples were collected at sunrise, midday and sunset; and in spring, early summer, late summer and autumn. The importance of drift for trout production was assessed using literature estimates of annual benthic production in the southern Appalachians, ecotrophic coefficients and food conversion efficiencies. 3. Abundance and biomass of terrestrial invertebrate inputs and drifting aquatic larvae were typically highest in spring and early summer. Aquatic larval abundances were greater than terrestrial invertebrates during these seasons and terrestrial invertebrate biomass was greater than aquatic larval biomass in the autumn. Drift rates of aquatic larval abundance and biomass were greatest at sunset. Inputs of terrestrial invertebrate biomass were greater than aquatic larvae at midday. Terrestrial invertebrate abundances were highest in streams with open canopies and streams adjacent to pasture with limited forest canopy. 4. We estimate the combination of benthic invertebrate production and terrestrial invertebrate inputs can support 3.3–18.2 g (wet weight) m−2 year−1 of trout, which is generally lower than values considered productive [10.0–30.0 g (wet weight) m−2 year−1]. 5. Our results indicate terrestrial invertebrates can be an important energy source for trout in these streams, but trout production is still low. Any management activities that attempt to increase trout production should assess trout food resources and ensure their availability. [ABSTRACT FROM AUTHOR]

Quantifying the spatial variability of species‐specific tree transpiration across hillslopes is important for estimating watershed‐scale evapotranspiration (ET) and predicting spatial drought effects on vegetation. The objectives of this study are to (1) assess sap flux density (Js) and tree‐level transpiration (Ts) across three contrasting zones a (riparian buffer, mid‐hillslope and upland‐hillslope, (2) determine how species‐specific Js responds to vapour pressure deficit (VPD) and (3) estimate watershed‐level transpiration (Tw) using Ts derived from each zone. During 2015 and 2016, we measured Js in eight tree species in the three topographic zones in a small 12‐ha forested watershed in the Piedmont region of central North Carolina. In the dry year of 2015, loblolly pine (Pinus taeda), Virginia pine (Pinus virginiana) and sweetgum (Liquidambar styraciflua) Js rates were significantly higher in the riparian buffer when compared to the other two zones. In contrast, Js rates in tulip poplar (Liriodendron tulipifera) and red maple (Acer rubrum) were significantly lower in the buffer than in the mid‐hillslope. Daily Ts varied by zone and ranged from 10 to 93 L/day in the dry year and from 9 to 122 L/day in the wet year (2016). Js responded nonlinearly to VPD in all species and zones. Annual Tw was 447, 377 and 340 mm based on scaled‐Js data for the buffer, mid‐hillslope and upland‐hillslope, respectively. We conclude that large spatial variability in Js and scaled Tw was driven by differences in soil moisture at each zone and forest composition. Consequently, spatial heterogeneity of vegetation and soil moisture must be considered when accurately quantifying watershed level ET. [ABSTRACT FROM AUTHOR]

Presents a study that compared consistency of species richness and relative abundance data collected concurrently using mist netting and point counts during landbird migration in riparian habitats along the middle Rio Grande of central New Mexico. Methodology; Point counts; Mist netting.

The hydrologic performance of a grass swale, a common stormwater control measure often utilized to drain roads, may potentially be improved using simple retrofits. Two rock check dams were retrofitted into an existing grass swale located in Knightdale, North Carolina, USA. The swale was monitored before and after check dam installation, and the addition of check dams improved runoff volume reduction (17%), peak flow mitigation, and hydraulic retention time in the swale, particularly for small (< 19 mm) and moderate (19–38 mm) rainfall events. The check dams were effective filters of gross solids, which eventually led to clogging and caused extended inundation and subsequent loss of swale vegetation. Because check dams are relatively inexpensive and simple vis-à-vis other stormwater control measure enhancements, their use for stormwater treatment is encouraged, provided they are adequately maintained. [ABSTRACT FROM AUTHOR]

The general picture of Pleistocene stratigraphy in the Outer Coastal Plain of North Carolina has changed significantly in the last five decades owing to new work involving subsurface coring, application of geophysical methods, radiometric and amino-acid dating, chronostratigraphic improvements, and high-resolution paleoenvironmental analyses. A crucial part of this change resulted from the concentration of attention to the thick, relatively complete succession of stratigraphic units within the Albemarle Embayment. Exposures at river banks, borrow pits and smaller excavations to the north and south of the embayment typically do not reveal much of the lateral variation of the familiar, named lithologic units, and successions are not as complete. These limited stratigraphic windows on Pleistocene stratigraphy in the region remain important opportunities for description and interpretation of stratigraphic units, which can be lithologically indistinguishable, but separated by unconformities and associated with different landforms--and therefore should be considered allostratigraphic units. Local exposures need to be analyzed and integrated into the regional stratigraphic framework using multiple methods if possible, in addition to the standard documentation of lithologies and most abundant macrofossils. Much remains to be done involving precise age determinations, correlations of units exposed along rivers and in excavations with allostratigraphic units delineated in the Albemarle Embayment, and matching units to Marine Isotope Stages and ultimately to Quaternary climate cycles. [ABSTRACT FROM AUTHOR]

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Mountain streams with rocky substrates and high turbulence are generally characterized by bryophytes rather than vascular plants. Conocephalum salebrosum (Snakeskin Liverwort) is a thallose bryophyte that occurs in damp soil along streambanks as well as on rocks and boulders in stream channels. Our objectives were to determine its prevalence on boulders in western North Carolina streams and characterize its habitat and chlorophyll levels. We documented Snakeskin Liverwort in 11 streams across 6 counties and 3 river basins; all had a circumneutral pH and low conductivity. We found patches of Snakeskin Liverwort in a variety of light conditions, but overall, patches were situated on boulders that received significantly less sunlight than nearby random boulders. Within channels, patches occurred more often along the edges of streams than in the center. Chlorophyll concentrations in thalli collected from 2 streams at different elevations and river basins did not differ significantly, suggesting similar photosynthetic potential. Mosses were present on ≥92% of boulders supporting Snakeskin Liverwort and on ≥90% of nearby random boulders. Vascular plants occurred in 50–93% of Snakeskin Liverwort patches, compared with 10–28% of random boulders. Graminoids (sedges and grasses) were the most common vascular plants aasociated with liverwort patches, followed by forbs. Our results suggest the thallose mats of Snakeskin Liverwort facilitate the establishment of rooted plants on boulders, which could enhance overall primary production in mountain streams. [ABSTRACT FROM AUTHOR]

Deforestation, followed by soil erosion and subsequent deposition of alluvium in valleys, played a critical role in the formation of historical terraces in much of the Southern Blue Ridge Mountains. Such terraces add a significant amount of sediment to the tributaries of the region as streams laterally erode the terrace banks. This study examined the contribution of total sediment yield derived solely from eroded stream banks in small watersheds (<20 km2), using floodplain widths as proxies for long-term lateral erosion rates. The raw data were derived from watersheds with different land covers (Coweeta Creek and Skeenah Creek watersheds in the Upper Little Tennessee River basin). Bank-derived sediment yield estimates were modeled in a Geographic Information System, using linear regression to relate floodplain widths and erodible terrace bank heights. We found total stream length to be a good predictor of both lateral erosion rates and erodible bank heights. Land cover, basin! network morphometrics, and reach-scale stream conditions were not good predictors. Modeled lateral migration and sediment yield results compare favorably to empirical measurements from five independent watersheds in the region. Modeled estimates fall within ±50% or better of the observed values, at 16.33 to 25.02 km-2 yr-1. [ABSTRACT FROM AUTHOR]

The article discusses hurricane effects on water quality and benthos in Cape Fear watershed in North Carolina and its natural and anthropogenic impacts. Topics discussed include effect of flooding on inputs of riparian swamp water to river channels and sewage treatment plant, diversions of millions of liters of raw and partially treated human waste into rivers, development of swine waste lagoons on concentrated organic waste and fall in Dissolved oxygen (DO) quantity in Cape Fear River.

Virginia spiraea (Spiraea virginiana Britton, Rosaceae) is a putative shade-intolerant, disturbance-adapted, riparian shrub species native to the southern Appalachian Mountains. This species was listed as threatened in 1990, and a federal recovery plan was developed in 1992. Current reassessment of the recovery plan includes proposals for propagation and out-planting to supplement and restore wild populations. Genotypes with greater shade acclimation would likely have higher survival in natural populations, would require less frequent shade-reduction management, and could be integrated into populations that need restoration. In summer 2022, we examined steady-state (maximum light-saturated photosynthetic, dark respiration rates, quantum yield, light compensation point) and dynamic (photosynthetic induction and loss patterns) photosynthetic characteristics, pigment concentrations, and specific leaf mass of cloned propagules from five elements of occurrence along the South Fork of the New River in Ashe County, North Carolina, along an artificial light gradient (100%, 75%, 50%, and 20% of full sun) in a common garden. Data were compared among light treatments using ANOVA or non-parametric tests. Light treatment had significant effects on maximum photosynthesis, dark respiration, specific leaf mass, and light compensation, but not quantum yield, pigment concentrations, or induction and loss times. Some parameters had plasticity similar to that seen in other woody shrubs, while others were less plastic. A surprising finding was that plants performed better under 75% full sunlight suggesting an ability to tolerate, and maybe even a preference for, partial shade in this species. Future studies should examine photosynthetic characteristics of individuals from genetically contrasting source populations. [ABSTRACT FROM AUTHOR]

• Wildfire is predicted to increase in severity and frequency with climate change. • Our study assesses effects of wildfire on terrestrial salamanders in two habitats. • Upland salamanders experienced declines in density and juvenile size class. • Forest managers can focus mitigation efforts towards more the more susceptible upland habitats. Wildfire is an important natural disturbance event that promotes landscape heterogeneity and regulates many wildlife communities. The compounding effects of fire suppression and climate change have increased the frequency and severity of wildfire, but the responses of many organisms to wildfire is unknown. Landscape heterogeneity, specifically microhabitats, may mediate and buffer the effects of wildfire, and evaluating variable responses to wildfire given habitat is key to developing a more cohesive understanding of population responses. Terrestrial plethodontid salamanders are likely disproportionality affected by wildfire events because of their lungless anatomy and reliance on cool and moist habitats. Our knowledge of salamander responses to wildfire in the short-term is limited due to the inherent challenge of opportunistically studying post-wildfire events. We capitalized on a wildfire event in western North Carolina, USA to determine the short-term (6–18-month post-fire) habitat-mediated responses of salamanders to wildfire using body size measurement and repeated count surveys. We observed precipitous declines of the red-legged salamander, Plethodon shermani, in exposed upland forests, but no apparent negative effects in riparian forests 18-months post-fire relative to unburned sites. We also observed a loss of juvenile size classes in the upland burned forest with only the largest adult individuals remaining 18-months post-fire. There were no size class differences in the riparian forests. Our results suggest riparian forests may be buffered from the effects of wildfire because canopy cover, vegetation, and soil duff layer are retained following a wildfire event. Salamander populations inhabiting riparian forests may be at less risk of declining than those in exposed habitats. Our results underscore the need to assess wildfire effects in all habitat types to fully determine the effects of disturbance to populations. [ABSTRACT FROM AUTHOR]

Stream mitigation is widely used to offset and restore anthropogenic stream degradations, yet ecosystem health is not always improved. Specific mitigation type may play a role in the potential for biotic improvement, with differing common mitigation practices including restoration and habitat enhancement. By looking at small factors in stream communities, such as macroinvertebrates, a larger connection can be made to the overall biotic integrity and quality of the aquatic habitat. This study used a Before-After-Control-Impact design to evaluate changes to biotic integrity of four streams in western North Carolina that underwent either complete restoration or habitat enhancement as compensatory mitigation under provisions of the United States Clean Water Act. We developed a Habitat Quality Improvement Index (HQII) to compare macroinvertebrate family-based metrics of habitat quality between 2011 (pre-mitigation) and 2021 (post-mitigation) and used a multivariate analysis to examine changes in macroinvertebrate family composition at each site. Analysis of HQII values using a Monte Carlo resampling procedure showed significant improvement at restored sites, whereas habitat quality declined significantly at sites that underwent habitat enhancement only. Our results indicate that restoration practices can have positive impacts on stream health, especially where habitat degradation is localized, and macroinvertebrate populations at high-quality upstream sections can provide a source for recolonization once habitat conditions improve. [ABSTRACT FROM AUTHOR]