Freshwater Science最新文献

{"title":"Nutrient limitation of periphytic algal assemblages in agricultural streams across grassland to boreal landscapes","authors":"Sydney Huculak, S. Tank, Gregory S. Piorkowski, Madison Kobryn, R. Vinebrooke","doi":"10.1086/722742","DOIUrl":"https://doi.org/10.1086/722742","url":null,"abstract":"Land-use practices can deteriorate the health of aquatic ecosystems in lower-order streams by increasing the availability of nutrients to periphytic algae. The magnitude of eutrophication likely depends in part on the nature of nutrient limitation and other local environmental factors. We used nutrient diffusing substrates and assessments of taxonomically diagnostic pigments to experimentally identify the drivers of nutrient limitation of periphytic algal assemblages across 30 streams which collectively spanned a gradient of agricultural land-use intensity (cropland, pasture, and nutrients) across Boreal Forest, Grassland, and Parkland ecoregions in Alberta, Canada. We identified N as the primary limiting factor of total algal biomass accrual. Overall, bacillariophytes made up most of the total algal biomass response to N. Dissolved inorganic N to total P ratios in the water column were consistently low, and P amendment altered assemblage composition by stimulating chlorophytes over bacillariophytes. Differences in soil types, precipitation, runoff, and leaching potential within and across ecoregions did not alter the algal responses to the experimental nutrient amendments. The effect of N-limiting conditions observed across most streams had greater relative importance than other potential abiotic factors (e.g., light) on algal growth. Whereas a historical focus on P management remains important, our findings highlight the need to increase the attention and focus on N in watershed management plans during the summer months to mitigate eutrophication of agricultural streams.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"577 - 598"},"PeriodicalIF":1.8,"publicationDate":"2022-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46353992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How extreme drought events, introduced species, and disease interact to influence threatened amphibian populations","authors":"Travis McDevitt-Galles, W. Moss, Dana M. Calhoun, C. Briggs, Pieter T. J. Johnson","doi":"10.1086/722679","DOIUrl":"https://doi.org/10.1086/722679","url":null,"abstract":"Over the past century, native amphibian species in California, USA, have declined in geographic range and population size, including precipitous declines of the California Red-legged Frog Rana draytonii Baird and Girard, 1852 and the California Tiger Salamander Ambystoma californiense Gray, 1853. Habitat loss, infectious disease (e.g., chytridiomycosis), and the introduction of invasive species are potential contributors to this decline, but it is unclear how these variables interact with extreme weather events, such as prolonged drought to affect amphibian population dynamics. We used a 7-y dataset (2013–2019) on amphibian breeding activity that encompassed a recent extreme drought event to assess 1) how breeding activities of these taxa differed during and after drought conditions and 2) the additive and interactive relationships of drought, chytrid fungal infection (Bd), and invasive species with the presence and abundance of larval amphibians. Based on 650 surveys of 110 lentic habitats in California, both amphibian species were highly sensitive to drought severity, such that the proportion of occupied sites during peak drought conditions decreased by 36% for R. draytonii and 87% for A. californiense relative to the initial year of the study. However, both taxa showed strong recovery, with increases in breeding occurrence as drought conditions eased in the following years (2016–2019). Invasive fishes and American Bullfrogs (Rana catesbeiana Shaw, 1802) also negatively predicted the occurrence and density of the 2 native taxa. Finally, we found that the relationship between Bd and R. draytonii larval density was influenced by drought conditions, suggesting that Bd’s transmission rates or effects on host persistence are sensitive to climate. These findings illustrate the ability of native taxa to recover from recent drought conditions and reinforce the importance of controlling invasive species for improving breeding activities of threatened amphibians.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"680 - 694"},"PeriodicalIF":1.8,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49111919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat and smoke from wildfires influence water temperature and dissolved oxygen levels in headwater streams","authors":"Ashley Sanders, A. A. Coble, Allison G. Swartz, Mark River, P. James, D. Warren","doi":"10.1086/722632","DOIUrl":"https://doi.org/10.1086/722632","url":null,"abstract":"Wildfire has become increasingly common and severe in forested landscapes across the western United States. Stream and air temperatures within these landscapes are influenced not only by direct heating during the fire but by shading from heavy smoke. In addition, dissolved oxygen (DO) can be affected by increased ash inputs from fire or reduced primary production under lower light conditions. Because collecting data as the event occurs is challenging, most research exploring fire effects on streams has focused on responses months to years after the event as opposed to during and immediately after the fire. We sought to understand how physical stream parameters change as wildfire burns near streams, how stream temperature responses vary through a stream reach, how parameters respond to shading from pervasive smoke during and shortly after the fire, and how fire severity correlates with observed changes. In this study, we report measurements of light, air temperature, stream temperature, and DO across eleven 2nd- to 4th-order streams in the western Cascade Mountains of Oregon, USA, 1 wk before, during, and 1 wk after an extensive wildfire in 2020. Burning near streams resulted in a brief increase in daily maximum stream temperature of 4.5°C at the most severely burned site but small increases or decreases at less affected sites. Longitudinal replication revealed that temperature responses can be patchy at relatively small scales (∼50 m). DO daily minima decreased by 1.3 to 16.9% saturation on the day of the fire, with the magnitude of effect corresponding to burn severity. Across all 11 sites, riparian and watershed estimates of Rapid Assessment of Vegetation Condition after Wildfire and soil burn severity were better correlated with stream temperature responses to fire than percentage of watershed burned. Smoke effects were pervasive, both spatially and temporally, resulting in decreased light, stream temperature maxima, and diurnal variation in DO. Our results suggest that acute changes to physical stream parameters caused minimal harm to aquatic biota at our sites, and the effects of smoke on physical stream parameters will likely impose larger immediate effects on headwater streams than heating from the fire itself.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"665 - 679"},"PeriodicalIF":1.8,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42965298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occupancy of invasive Northern Crayfish (Faxonius virilis) in northern streams is associated primarily with water temperature","authors":"Victoria Van Mierlo, S. Green, C. Emmerton, M. Nasr, C. Buendia, Faye R. Wyatt, M. Poesch","doi":"10.1086/722576","DOIUrl":"https://doi.org/10.1086/722576","url":null,"abstract":"Invasive species are the 2nd-greatest threat to global freshwater biodiversity. Crayfish are especially robust invaders due to their omnivorous nature and ability to compete both directly (resource procurement) and indirectly (habitat occupation and modification) with native species. The Northern Crayfish (Faxonius virilis Hagen, 1870) was introduced to the North Saskatchewan River basin (Alberta, western Canada) and has persisted there since the early 1990s. Faxonius virilis’ impacts on native fish assemblages in the North Saskatchewan River have yet to be assessed, even though the watershed is ecologically, economically, and culturally valuable and home to multiple sensitive and at-risk fish species. We aimed to identify the instream environmental characteristics associated with F. virilis occupancy in the North Saskatchewan River basin and to determine which currently unoccupied tributaries are most vulnerable to F. virilis invasion. We used occupancy modeling to meet these objectives. We deployed 24-h baited crayfish traps and measured water temperature, turbidity, flow velocity, and physical complexity at 37 sites along the Alberta portion of the North Saskatchewan River basin. We detected F. virilis at 13/37 sites with no occurrences detected in the upper basin. Occupancy model selection and averaging revealed that water temperature alone was associated with occupancy of F. virilis in the North Saskatchewan River basin. Streams with mean summer water temperatures >∼19°C were ≥50% more likely to be occupied by F. virilis than cooler streams and are at highest risk of invasion. Further, we found that streams with mean summer water temperatures <∼15°C had a <25% chance of becoming occupied by F. virilis than warmer streams. Coldwater streams may thus have some natural protection against F. virilis invasion. The results from this study provide practical guidelines for watershed management of invasive F. virilis populations in western Canadian river basins. Managing F. virilis is particularly important and time sensitive because F. virilis’ range will likely expand when water temperatures in the basin rise because of climate change.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"650 - 664"},"PeriodicalIF":1.8,"publicationDate":"2022-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42461854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Front Matter","authors":"","doi":"10.1086/722399","DOIUrl":"https://doi.org/10.1086/722399","url":null,"abstract":"Freshwater Science, Volume 41, Issue 3, September 2022. <br/>","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"33 23","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138503009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Community-powered urban stream restoration: A vision for sustainable and resilient urban ecosystems","authors":"M. Scoggins, D. Booth, T. Fletcher, M. Fork, Ana M González, R. Hale, R. Hawley, A. Roy, E. E. Bilger, N. Bond, M. J. Burns, K. Hopkins, K. Macneale, E. Martí, S. McKay, M. Neale, M. Paul, B. Ríos-Touma, Kathryn L. Russell, Robert F. Smith, S. Wagner, S. Wenger","doi":"10.1086/721150","DOIUrl":"https://doi.org/10.1086/721150","url":null,"abstract":"Urban streams can provide amenities to people living in cities, but those benefits are reduced when streams become degraded, potentially even causing harm (disease, toxic compounds, etc.). Governments and institutions invest resources to improve the values and services provided by urban streams; however, the conception, development, and implementation of such projects may not include meaningful involvement of community members and other stakeholders. Consequently, project objectives may be misaligned with community desires and needs, and projects may fail to achieve their goals. In February 2020, the 5th Symposium on Urbanization and Stream Ecology, an interdisciplinary meeting held every 3 to 5 y, met in Austin, Texas, USA, to explore new approaches to urban stream projects, including ways to maximize the full range of potential benefits by better integrating community members into project identification and decision making. The symposium included in-depth discussion about 4 nearby field case studies, participation of multidisciplinary urban stream experts from 5 continents, and input from the Austin community. Institutional barriers to community inclusion were identified and analyzed using real-world examples, both from the case studies and from the literature, which clarified disparities in power, equity, and values. Outcomes of the symposium have been aggregated into a vision that challenges the present institutional approach to urban stream management and a set of strategies to systematically address these barriers to improve restoration solutions. Integrating community members and other stakeholders throughout the urban restoration process, and a transparent decision-making process to resolve divergent objectives, can help identify appropriate goals for realizing both the ecological and social benefits of stream restoration.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"404 - 419"},"PeriodicalIF":1.8,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41395501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Urbanization and stream ecology: Moving the bar on multidisciplinary solutions to wicked urban stream problems","authors":"M. Fork, K. Hopkins, J. Chappell, R. Hawley, S. Kaushal, B. Murphy, B. Ríos-Touma, A. Roy","doi":"10.1086/721470","DOIUrl":"https://doi.org/10.1086/721470","url":null,"abstract":"Decades of research on the effects of urbanization on stream ecology have shown that urban stream problems are inherently wicked. These problems are wicked in the sense that they are difficult to solve because information is incomplete, changing, or conflicting and because finding potential solutions often requires input from stakeholders who can have conflicting and competing values. The 5th Symposium on Urbanization and Stream Ecology (SUSE5) in February 2020 brought together diverse perspectives from scientists, managers, practitioners, and local communities. Participants at SUSE5 discussed the state of the science in urban stream ecology and worked through in-depth case studies in teams to tackle complex real-world problems in urban stream management. The papers in this special series on urbanization and stream ecology include empirical research studies and synthesis papers sparked by discussions at SUSE5 and advance multidisciplinary solutions to wicked urban stream problems.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"398 - 403"},"PeriodicalIF":1.8,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46530741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highlighting assumptions of community engagement in urban stream restoration","authors":"Denzell A. Cross, J. Chappell","doi":"10.1086/721540","DOIUrl":"https://doi.org/10.1086/721540","url":null,"abstract":"Restoration practitioners experience mixed results when they try to engage community members in urban stream restoration projects. In some cases, practitioners make presumptions about community responses to restoration that lead to unsuccessful engagement and detract from restoration goals. During the 5th Symposium on Urbanization and Stream Ecology, we noticed that participants repeatedly discussed community stakeholder engagement as a tool for effective urban stream restoration. However, most presenters did not acknowledge that typical engagement strategies do not consider how the target community’s social, economic, and political dynamics will influence stakeholder response. As a result, many practitioners make assumptions about communities that can be counterproductive to engagement efforts. Here, we discuss 4 underlying assumptions that many researchers make when trying to engage community stakeholders: 1) community members and researchers have the same project goals, 2) educating residents is essential in garnering community support, 3) the community will benefit from the restoration effort, and 4) the community has solutions to contribute to the technical aspects of the restoration effort. We present and develop these assumptions in the context of relevant urban stream restoration projects and highlight the complexity represented across communities where urban stream restoration projects can take place. Land managers and researchers must first cultivate a thoughtful understanding of the community and its existing socioeconomic capacities before integrating community stakeholders into urban stream restoration projects. We believe highlighting these societal complexities will promote a deeper consideration of appropriate engagement strategies for urban stream restoration projects.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"532 - 538"},"PeriodicalIF":1.8,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47971330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stream macroinvertebrate reintroductions: A cautionary approach for restored urban streams","authors":"S. Clinton, Jacqueline Hartman, K. Macneale, A. Roy","doi":"10.1086/721471","DOIUrl":"https://doi.org/10.1086/721471","url":null,"abstract":"Macroinvertebrate assemblages often remain depauperate in physically restored urban streams despite efforts to improve habitat conditions and increase species abundance and diversity. The lack of biological recovery may be due to a lack of a natural, nearby source of colonists, and this has inspired researchers and practitioners to reintroduce macroinvertebrates in otherwise restored urban streams to jump start the recovery process. However, without standardized guidelines that describe reintroduction best practices, some reintroduction programs may create additional problems (e.g., disease spread, genetic homogenization, population loss). To reduce these risks and limit a potential waste of resources, a cautionary approach is warranted. In this paper we summarize current stream reintroduction knowledge and detail best practices for aquatic macroinvertebrate reintroduction in restored urban streams. We provide criteria that managers can use to determine whether reintroduction is appropriate and demonstrate how researchers can use reintroduction as a tool to test hypotheses regarding factors limiting recolonization. We provide guidance for how to set clear reintroduction goals, select donor sites, determine the number of organisms required, establish reintroduction frequency and timing, and overcome challenges associated with monitoring. This framework can help managers create more successful reintroduction programs that can benefit urban stream restoration.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"507 - 520"},"PeriodicalIF":1.8,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43891163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Weighted stream temperature tolerance index is insensitive to changes in stream fish composition","authors":"McKayla Jarvie, Donald A. Jackson","doi":"10.1086/721539","DOIUrl":"https://doi.org/10.1086/721539","url":null,"abstract":"Freshwater fish species require and compete for specific water temperatures and thermal regimes to maximize physiological and behavioral processes; however, the thermal habitats on which freshwater fish rely are being modified by local human activities and global climate change. Water temperature measurements that are often used to determine thermal regimes allow predictions of species occurrence in the absence of assemblage surveys. Methods that connect assemblage composition with temperature provide additional information that otherwise is lost when temperature is measured alone. Using stream fish assemblage data collected over 2 decades from various biomonitoring programs in southern Ontario, Canada, we tracked site-level changes in stream fish assemblage composition from numerous watersheds. We also assessed the utility of using a weighted species association tolerance index with respect to water temperature (WSATI-WT) that weights the abundance of each species in an assemblage by their thermal preference to generate an assemblage temperature preference. We tracked temporal changes in assemblage temperature preferences and used bootstrapping to assess the effects of sampling variability on this index. Fish assemblage composition changed over time in all watersheds, but these changes had differential effects on WSATI-WT values. Temporal changes in WSATI-WT values ranged from −9.43 to 5.04°C, of which 68% were negative and 32% positive. These changes imply that, over time, the thermal regime of some sites changed, but bootstrapping showed that WSATI-WT estimates could differ by ≤10°C (mean = 1.57°C) due to sampling variability alone. Examination of the variation in bootstrapped values relative to species composition indicates that uncommon or underrepresented species that have atypical thermal preferences relative to the other species within individual samples may have a large influence on WSATI-WT values. We must develop robust and resilient methods of tracking assemblage responses to warming temperatures if we hope to manage watersheds and species that are sensitive to warming temperatures.","PeriodicalId":48926,"journal":{"name":"Freshwater Science","volume":"41 1","pages":"386 - 397"},"PeriodicalIF":1.8,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46463772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}