Beaver-Driven Peatland Ecotone Dynamics: Impoundment Detection Using Lidar and Geomorphon Analysis

This investigation focused on remotely detecting beaver impoundments and dams along the boreal-like peatland ecotones enmeshing Cranberry Glades Botanical Area, a National Natural Landmark in mountainous West Virginia, USA. Beaver (Castor spp.) are renowned for their role as ecosystem engineers. They can alter local hydrology, change the ratios of meadow to woodland, act as buffers against drought and wildfire, and influence important climate parameters such as carbon retention and methanogenesis. The Cranberry Glades (~1000 m a.s.l.) occupy ~300 ha, including ~40 ha of regionally rare, open peatlands. Given the likely historical role of beaver activity in the formation and maintenance of peatland conditions at Cranberry Glades, monitoring of recent activity may be useful in predicting future changes. We analyzed remotely sensed data to identify and reconstruct shifting patterns of surface hydrology associated with beaver ponds and dams and developed a novel application of geomorphons to detect them, aided by exploitation of absences and errors in Lidar data. We also quantified decadal-timescale dynamics of beaver activity by tallying detectable active impoundments between 1990–2020, revealing active/fallow cycles and changing numbers of impoundments per unit area of suitable riparian habitat. This research presents both a practical approach to monitoring beaver activity through analysis of publicly available data and a spatiotemporal reconstruction of three decades of beaver activity at this rare and imperiled “Arctic Island” of the southern High Alleghenies.

Evidence of effect of riparian attributes on listed freshwater fishes and mussels and their aquatic critical habitat: a systematic map protocol

Background Habitat that is necessary for the survival and recovery of a species listed as threatened, endangered or extirpated (i.e., Critical Habitat) is protected in Canada. For freshwater aquatic species, Critical Habitat may include the riparian zone, however, it is unclear how much of this riparian habitat needs to be protected to support the survival and recovery of a listed species. The riparian zone mainly affects aquatic species through its indirect effect on aquatic habitat according to five main processes: erosion, filtration, infiltration, shading, and subsidization. To provide quantitative evidence to support the delineation of riparian Critical Habitat, a systematic map will be used to create a searchable database containing the current state of knowledge regarding the relationships between the riparian zone attributes (e.g., size, vegetation) and fishes and mussels, aquatic features, and riparian processes. Methods We will search for primary research articles in bibliographic databases and relevant organizational websites for primary literature, theses, preprints, and grey literature including reports, along with models using a search string specific to riparian habitat. The results will be screened at title and abstract, and full text levels against predefined inclusion criteria and consistency checking will be performed to ensure the inclusion criteria are consistent across multiple reviewers. Quantitative and qualitative data including study details and methods, the riparian habitat, and the waterbody and upland habitat use will be extracted. The findings of the systematic map will be provided in a manuscript and a searchable database accompanied by a decision tree to support biologists in providing scientifically defensible delineation of riparian Critical Habitat for aquatic species at risk in Canada.

Systematic review protocol to guide the delineation of critical habitat in the riparian zone for listed freshwater fishes and mussels

BackgroundHabitat that is necessary for the survival and recovery of a species listed as threatened, endangered, or extirpated (i.e., Critical Habitat) is protected in Canada. For aquatic species, Critical Habitat may include riparian habitat, however it is unclear how much of this riparian habitat needs to be protected to support the survival and recovery of a listed species (primary question). To provide quantitative evidence to support the delineation of riparian Critical Habitat, the systematic review will be used to determine the relationships between aquatic and riparian attributes and the dependence of these relationships on the quantity of riparian habitat (secondary questions). MethodsWe will search for primary research articles in bibliographic databases for primary literature, theses, and preprints and for grey literature including reports published on relevant organizational using a search string consisting of substrings for riparian habitat, and for riparian processes (i.e., erosion, filtration, infiltration, shading, and subsidization) or aquatic attributes. The results will be screened at title and abstract, and full text levels against predefined inclusion criteria and consistency checking will be performed on a subset of 100 records to ensure the inclusion criteria are consistent across multiple reviewers. Quantitative data on the riparian and aquatic habitats will be extracted and synthesized to perform dose response meta-analyses. First, the riparian habitat attributes will be combined using probabilistic principal component analysis to develop appropriate dependent variables that describe riparian habitat types. The principal component axes will then be used in a multiple regression analysis along with a measure of the riparian habitat size, and study specific identifiers and modifiers to determine the shape of the relationship and the magnitude of the effect of on the aquatic habitat. These analyses will be used to determine the extent of riparian habitat required to maintain natural levels of riparian process to protect aquatic Critical Habitat. The findings of the systematic review will support the delineation of riparian Critical Habitat for aquatic species at risk in Canada.

Benthic Diatom Communities in Urban Streams and the Role of Riparian Buffers

Urbanization impacts stream ecosystems globally through degraded water quality, altered hydrology, and landscape disturbances at the catchment and riparian scales, causing biodiversity losses and altered system functioning. Addressing the “urban stream syndrome” requires multiple mitigation tools, and rehabilitation of riparian vegetation may help improve stream ecological status and provide key ecosystem services. However, the extent to which forested riparian buffers can help support stream biodiversity in the face of numerous environmental contingencies remains uncertain. We assessed how a key indicator of stream ecological status, benthic diatoms, respond to riparian habitat conditions using 10 urban site pairs (each comprising of one unbuffered and one buffered reach), and additional urban downstream and forest reference upstream sites in the Oslo Fjord basin. Diatom communities were structured by multiple drivers including spatial location, land use, water quality, and instream habitat. Among these, riparian habitat condition independently explained 16% of variation in community composition among site pairs. Changes in community structure and indicator taxa, along with a reduction in pollution-tolerant diatoms, suggested tangible benefits of forested riparian buffers for stream biodiversity in urban environments. Managing urban impacts requires multiple solutions, with forested riparian zones providing a potential tool to help improve biodiversity and ecosystem services.

Evaluasi Rehabilitasi Riparian Sungai Ranggeh dengan Indikator Komunitas Makrozoobenthos

<strong>Evaluation of Riparian Rehabilitation in River River Usingthe Macrozoobenthos Community Indicator. </strong>Macrozoobenthos organism is one of aquatic biota which is often used to assess the ecosystems health of river.The evaluation of riparian habitat rehabilitation using benthic macroinvertebrates has been commonly used in many countries. The purposes of this study were to evaluate the impact of Ranggeh river riparian rehabilitation and to determine environmental parameters that influenced benthic macroinvertebrate communities in Ranggeh River. This research was conductedfrom February to September 2019. Benthic macroinvertebrate Benthic macroinvertebrates, river, evaluation, EPT, rehabilitationsamples were collected using Hess Sampler in a sampling area of 0.2 m². This evaluation was carried out after two months since the rehabilitation of riparian habitat completed. The results show that rehabilitation of the riparian habitat has changed the community, in the aspects of biological metrics of taxa number, abundance, and taxa numbersof Ephemeroptera, Plecoptera, and Trichoptera (EPT). Furthermore, the taxa number and EPT metrics increased after habitat rehabilitation, however the abundance decreased slightly. In addition, the taxa number metric was positively correlated with conductivity parameter (r = 0.8), but negatively correlatedto turbidity (r = -0.91) and pH (r = -0.77). Meanwhile, the EPT metric was negatively correlated with turbidity parameters (r = -0.76) and %<em>embeddedness</em> (r = -0.94). The total abundance metric was not sensitive to the parameters measured in this study. Meanwhile, biological metrics for taxa number and EPT can be used to assess rehabilitation success of river ecosystem habitats

Influence of Riparian Habitat and Ground Covers on Threecornered Alfalfa Hopper (Hemiptera: Membracidae) Populations in Vineyards

Grapevine red blotch virus (GRBV) is the causal agent of grapevine red blotch disease, which affects wine grapes and leads to reduced crop yield and quality. While some virus spread can be attributed to the propagation of infected plant material, a greenhouse assay recently demonstrated that the threecornered alfalfa hopper (Membracidae: Spissistilus festinus Say) can transmit GRBV between grapevines. While S. festinus is not considered an economic pest of wine grapes, this species is present in California vineyards and their feeding can cause petiole girdling. Recent surveys have noted a correlation between S. festinus populations and GRBV-positive vines in vineyard areas adjacent to riparian habitat. Here, S. festinus populations were monitored over a 2-yr period at multiple vineyard sites adjacent to riparian habitats. At each site, insects were sampled from ground covers and the vine canopy at the vineyard edge and interior, and vines in both locations were evaluated for petiole girdling. Results indicate that there was no difference in abundance of S. festinus at the vineyard edge and interior. Populations in the vine canopy were highest in the late spring and early summer, and this was followed by the appearance of petiole girdling, indicating a key period of potential GRBV transmission. Furthermore, activity in the vine canopy appears to be amplified when the quality of ground covers is reduced as the season progresses. That said, overall populations of S. festinus were relatively low and additional work is needed to characterize the timing and efficiency of transmission under field conditions.