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Статті в журналах з теми "Flow-ecology relationship"

1

Yin, Zheng Jie, Jin Chen, and Ji Jun Xu. "Application of Multiple Environmental Flow Methods to Optimize Cascade Dams Operation in the Lower Jinsha River." Advanced Materials Research 955-959 (June 2014): 3057–64. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.3057.

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Анотація:
To mitigate possible negative impacts of cascade dams in the Lower Jinsha River and maintain the natural flow regime of national natural reserve areas of rare and special fishes of the upper Yangtze River, environmental flow (e-flow) demands need to be considered in the cascade dams operation. Due to lack of regular ecological observation data, multiple hydrology-based e-flow methods including Tennant, minimum monthly flow, 7Q10 and Q90 are applied to provide specific e-flow prescripts to guide the reservoir release. A joint operation optimization model is developed for the cascade dams in the Lower Jinsha River for maximal hydropower generation under various e-flow constraints. The economic and ecological performances of cascade dams operation are evaluated by total hydropower outputs and hydrological alteration degree of downstream river individually. The operation results are analyzed and discussed, and some questions on the tradeoff relationship between ecology and hydropower generation, inherent relationship between ecological constrains and hydrological alteration, and rationality criteria of e-flow are further addressed. The conclusions indicate : (1) optimal operation for ecological considerations under e-flow constrains only reduce hydropower outputs slightly, no more than 2.4%; (2) e-flow constrains help lower hydrological alteration induced by hydropower dams, among the four e-flow methodologies Tennant is best in term of ecology; (3) there is a limitation for hydrology-based e-flow methodologies, and it is necessary to stress ecological foundation and ecological relevance for e-flow methodology. The paper will provide technical references for future ecological re-operation of the cascade dams.
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2

Chen, Ang, Miao Wu, and Michael E. McClain. "Classifying Dams for Environmental Flow Implementation in China." Sustainability 12, no. 1 (December 21, 2019): 107. http://dx.doi.org/10.3390/su12010107.

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Анотація:
The implementation of environmental flows is of the utmost importance for ecosystem protection and restoration in dammed rivers. A key challenge in optimizing dam regulation is the uncertainty of the ecohydrology relationship between flow release and ecological response. In the present paper, we develop a framework of dam classification to organize the categories of the ecohydrology relationship for implementing environmental flows. Dams are classified from three major categories that differ in dam properties, hydrological alteration, and downstream hydrobiological diversities based on the relationship of hydrology and ecology. Finally, 773 dams in China are screened and ranked into four classes involving a great diversity of environmental flow components. A classification of dams that utilizes the implementation of environmental flows is presented. (1) Class 1 includes dams with rare and endangered fish species in the downstream. It is the category with the highest priority for environmental flow releases and regulation, requiring continuous flow and flood pulse components for fish spawning and migration. (2) Class 2 includes dams with significant hydrological alteration in the downstream. It is the category with second priority for environmental flow releases and regulation, requiring natural hydrological regimes simulation or complete flow component recovery for optimizing the flow duration curve and mitigating adverse impacts of dam operation. (3) Class 3 includes dams with a high degree of regulation where there is urgency for environmental flow releases and regulation, requiring that minimum flow is guaranteed by cascade reservoir regulation. (4) Class 4 includes dams with a low degree of regulation where there is less urgency for environmental flow releases and regulation. This classification method is important for future research, including environmental flow release regulation and the effectiveness evaluation of environmental flow adaptive management. It will be useful for guiding the implementation of environmental flows.
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3

Jacoby, David M. P., Penthai Siriwat, Robin Freeman, and Chris Carbone. "Is the scaling of swim speed in sharks driven by metabolism?" Biology Letters 11, no. 12 (December 2015): 20150781. http://dx.doi.org/10.1098/rsbl.2015.0781.

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The movement rates of sharks are intrinsically linked to foraging ecology, predator–prey dynamics and wider ecosystem functioning in marine systems. During ram ventilation, however, shark movement rates are linked not only to ecological parameters, but also to physiology, as minimum speeds are required to provide sufficient water flow across the gills to maintain metabolism. We develop a geometric model predicting a positive scaling relationship between swim speeds in relation to body size and ultimately shark metabolism, taking into account estimates for the scaling of gill dimensions. Empirical data from 64 studies (26 species) were compiled to test our model while controlling for the influence of phylogenetic similarity between related species. Our model predictions were found to closely resemble the observed relationships from tracked sharks, providing a means to infer mobility in particularly intractable species.
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4

Lange, Katharina, Colin R. Townsend, and Christoph D. Matthaei. "Inconsistent Relationships of Primary Consumer N Stable Isotope Values to Gradients of Sheep/Beef Farming Intensity and Flow Reduction in Streams." Water 11, no. 11 (October 26, 2019): 2239. http://dx.doi.org/10.3390/w11112239.

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Анотація:
Stable isotope values of primary consumers have been proposed as indicators of human impacts on nitrogen dynamics. Until now, these values have been related only to single-stressor gradients of land-use intensity in stream ecology, whereas potential interactive effects of multiple stressors are unknown. It also remains unknown whether stable isotope values of different primary consumers show similar relationships along gradients of stressor intensities. We sampled three common invertebrate grazers along gradients of sheep/beef farming intensity (0–95% intensively managed exotic pasture) and flow reduction (0–92% streamflow abstracted for irrigation). The δ15N values of the three primary consumers differed substantially along stressor gradients. Deleatidium δ15N values were positively related to farming intensity, showing a saturation curve, whereas Physella snail δ15N values were negatively related to farming intensity and Potamopyrgus snail δ15N values showed no relationship. In addition, Deleatidium stable isotope values responded positively to flow reduction intensity, a previously unstudied variable. An antagonistic multiple-stressor interaction was detected only for the mayfly Deleatidium, which occurred in streams experiencing up to 53% farming intensity. The lack of consistency in the relationships of the most important primary consumer grazers along the studied gradients may reduce their suitability as an indicator of anthropogenic N inputs.
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5

Chen, Mufeng, Zengchuan Dong, Wenhao Jia, Xiaokuan Ni, and Hongyi Yao. "Multi-Objective Joint Optimal Operation of Reservoir System and Analysis of Objectives Competition Mechanism: A Case Study in the Upper Reach of the Yangtze River." Water 11, no. 12 (December 1, 2019): 2542. http://dx.doi.org/10.3390/w11122542.

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Анотація:
The multi-objective optimal operation and the joint scheduling of giant-scale reservoir systems are of great significance for water resource management; the interactions and mechanisms between the objectives are the key points. Taking the reservoir system composed of 30 reservoirs in the upper reaches of the Yangtze River as the research object, this paper constructs a multi-objective optimal operation model integrating four objectives of power generation, ecology, water supply, and shipping under the constraints of flood control to analyze the inside interaction mechanisms among the objectives. The results are as follows. (1) Compared with single power generation optimization, multi-objective optimization improves the benefits of the system. The total power generation is reduced by only 4.09% at most, but the water supply, ecology, and shipping targets are increased by 98.52%, 35.09%, and 100% at most under different inflow conditions, respectively. (2) The competition between power generation and the other targets is the most obvious; the relationship between water supply and ecology depends on the magnitude of flow required by the control section for both targets, and the restriction effect of the shipping target is limited. (3) Joint operation has greatly increased the overall benefits. Compared with the separate operation of each basin, the benefits of power generation, water supply, ecology, and shipping increased by 5.50%, 45.99%, 98.49%, and 100.00% respectively in the equilibrium scheme. This study provides a widely used method to analyze the multi-objective relationship mechanism, and can be used to guide the actual scheduling rules.
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6

Tucker, Marlee A., and Tracey L. Rogers. "Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals." Proceedings of the Royal Society B: Biological Sciences 281, no. 1797 (December 22, 2014): 20142103. http://dx.doi.org/10.1098/rspb.2014.2103.

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Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial ( n = 51) and marine ( n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities.
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7

Newson, M. D., and C. L. Newson. "Geomorphology, ecology and river channel habitat: mesoscale approaches to basin-scale challenges." Progress in Physical Geography: Earth and Environment 24, no. 2 (June 2000): 195–217. http://dx.doi.org/10.1177/030913330002400203.

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The physical component of river channel (instream) habitat is of acknowledged significance, particularly in headwater streams; furthermore, physical habitats have been heavily impacted by human needs for river services: principally flood defence (channel modification) and water resources (flow regulation). Despite the control exercised on physical habitats by fluvial geomorphology (channel shape, bed material size, bedforms and bars) and flow regime (including the varying hydraulics of flow around these forms), their interaction has hitherto lacked a distinctive spatial formulation and biological validation. This article describes the challenges faced by a need (in both theoretical and practical areas) to understand the detail of physical habitat conditions in stream channels. A number of mesoscale approaches are emerging, both from ecology and geomorphology. We outline the field validation of a ‘habitat hydraulics’ approach to the interaction between river discharge and channel form. Qualitative ‘flow types’ are shown to be representative of discrete hydraulic conditions within mesoscale units of the channel bed described as ‘physical biotopes’. The approach is compared with parallel ecological research on ‘mesohabitats’ and ‘functional habitats’. The extent, pattern and discharge-variability of physical biotopes can be surveyed in the field and used as a spatial guide to biological sampling (in this case for benthic invertebrates). Biological patterns (at the scale sampled here) appear to respond first to the river continuum concept’s longitudinal zonation of the channel, but there is a marked secondary signal in statistical analyses from the pattern of biotopes. Given the promise of the physical biotope approach, its logical extension in predictive mode is via the hierarchical concepts shared by freshwater ecologists and geomorphologists; however, there is little agreement on scale terminology, hierarchical principles and, above all, a truly geo-morphological channel classification, based on reaches, into which mesoscale habitat typologies could be fed. Assuming a relationship between biological diversity and that of physical biotopes it should be the aim of river managers, whether intervening in the channel form or its flow regime, to optimize certain parameters of the pattern of biotopes; these parameters should be a focus for future research. Both the rapid survey and proper description of these patterns will benefit from the application of remote-sensing technology, improved instruments for microscale hydraulic studies and a GIS approach based upon the spatial principles of landscape ecology.
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8

Wang, Hong Tao, Jin Yong Zhao, Gai Ling Wang, and Qing Hong Huangfu. "Significance of Ecohydraulics in Aquatic Ecosystem Protection." Advanced Materials Research 864-867 (December 2013): 2413–17. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.2413.

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Ecohydraulics is an emerging interdisciplinary science and mainstream engineering researching on the interaction relationship between hydrodynamic characteristic and aquatic ecosystem, it integrates biology, geology, hydrology, morphology, ecology, engineering and other disciplines. Based on the collection of literature on ecohydraulics from Web of Science database, the bibliometric analysis on 563 literatures from the year 1991 to 2012 has been conducted, including publication year, author, country, institution, subject, source journal and keyword analysis. Some conclusions have been made that these literatures on ecohydraulics are growing exponentially year by year; these literature involves a lot of authors and forms three research groups which scattered in Britain, the United States and New Zealand, the result clearly shows a positive correlation between the number of published literatures and the length of the research history in this subject; the main institutions of these literature include United States Geological Survey, National Institute of Water and Atmospheric Research, Chinese Academy of Sciences, University of Lyon and University of Birmingham; and the subjects of these literature include environmental sciences & ecology, water resources, marine & freshwater biology, engineering and other subjects; more than 40% of the literature published in journals with the impact factors greater than 2.0. The main research contents are as follow: biological characteristics of aquatic organism, the impact of hydrodynamics on river habitats and aquatic organisms and, the feedback of the organism on flow. Theoretical analysis, system testing, statistical analysis and hybrid analog-digital simulation are primary research techniques and applications of the research concentrate on environmental flow requirement, habitat assessment, eco-engineering design and flow field control.
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9

von Cramon-Taubadel, Noreen, and Stephen J. Lycett. "Assessing the relative impact of historical divergence and inter-group transmission on cultural patterns: a method from evolutionary ecology." Philosophical Transactions of the Royal Society B: Biological Sciences 373, no. 1743 (February 12, 2018): 20170054. http://dx.doi.org/10.1098/rstb.2017.0054.

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In the study of cultural evolution, observed among-group affinity patterns reflect the effects of processes such as mutation (e.g. innovation and copying error), between-group interaction (culture flow), drift and selection. As in biology, cultural affinity patterns are often spatially correlated, making it difficult to distinguish between the opposing geographically mediated forces of divergence and interaction, which cause groups to become more distinct or similar over time, respectively. Analogous difficulties are faced by evolutionary biologists examining the relationship between biological affinity and geography, particularly at lower taxonomic levels where the potential for gene flow between lineages is greatest. Tree models are generally used to assess the fit between affinity patterns and models of historical divergence. However, factors driving lineage divergence are often spatially mediated, resulting in tree models that are themselves geographically structured. Here, we showcase a simple method drawn from evolutionary ecology for assessing the relative impact of both geographically mediated processes simultaneously. We illustrate the method using global human craniometric diversity and material culture from the northern coast of New Guinea as example case studies. This method can be employed to quantify the relative importance of history (divergence) and geographically mediated between-group interaction (culture flow) in explaining observed cultural affinity patterns. This article is part of the theme issue ‘Bridging cultural gaps: interdisciplinary studies in human cultural evolution’.
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10

Clark, René D., Matthew L. Aardema, Peter Andolfatto, Paul H. Barber, Akihisa Hattori, Jennifer A. Hoey, Humberto R. Montes, and Malin L. Pinsky. "Genomic signatures of spatially divergent selection at clownfish range margins." Proceedings of the Royal Society B: Biological Sciences 288, no. 1952 (June 9, 2021): 20210407. http://dx.doi.org/10.1098/rspb.2021.0407.

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Understanding how evolutionary forces interact to drive patterns of selection and distribute genetic variation across a species' range is of great interest in ecology and evolution, especially in an era of global change. While theory predicts how and when populations at range margins are likely to undergo local adaptation, empirical evidence testing these models remains sparse. Here, we address this knowledge gap by investigating the relationship between selection, gene flow and genetic drift in the yellowtail clownfish, Amphiprion clarkii, from the core to the northern periphery of the species range. Analyses reveal low genetic diversity at the range edge, gene flow from the core to the edge and genomic signatures of local adaptation at 56 single nucleotide polymorphisms in 25 candidate genes, most of which are significantly correlated with minimum annual sea surface temperature. Several of these candidate genes play a role in functions that are upregulated during cold stress, including protein turnover, metabolism and translation. Our results illustrate how spatially divergent selection spanning the range core to the periphery can occur despite the potential for strong genetic drift at the range edge and moderate gene flow from the core populations.
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Дисертації з теми "Flow-ecology relationship"

1

Vallefuoco, Francesca. "Advancing quantitative understanding of flow-ecology relations in Alpine rivers." Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/348479.

Повний текст джерела
Анотація:
Anthropic impacts adversely affect the productivity, integrity, connectivity, and resilience of riverine ecosystems, with widespread cumulative effects on the biota and biodiversity. The natural flow regime is a fundamental driver of physical and chemical processes, determining the morphological profile of the river systems and sustaining the complex network of ecological interactions and biological patterns. Therefore, in order to reach the environmental goals required by the binding legislation, and achieve a sustainable use of water resources, it is urgent to understand the mechanisms behind changes in the structure of biological communities along gradients of human disturbances which affect the flow regime. Indicators based on macroinvertebrates are widely used to assess the ecological status of water bodies, given their sensitivity/tolerance to pollution. However, in Alpine running waters, where chemical quality is less impacted than in lowland rivers, it is particularly important and valuable to detect the hydro-morphological alterations, and to discriminate them from chemical degradation, based on the responses of benthic macroinvertebrates to such multiple stressors. Therefore, this thesis aims at: i) examining the taxonomic and functional responses of macroinvertebrate communities to the different anthropogenic pressures acting on river systems; ii) evaluating the taxa/functional traits which mostly discriminate between hydrological and morphological alterations, and chemical degradation, to support effective bioindication methods. Focus of the research is to assess the macroinvertebrate community responses to the alterations caused by flow regulation and morphological alterations, which include water abstraction, diversion, stocking and the intermittent release of water from hydropower plants, banks artificialization and construction of weirs, dams, and other structures, each of these with environmental consequences of different scale and magnitude, such as the interruption of the longitudinal continuity, residual flow release and hydropeaking. The first part of this thesis is based on two empirical field studies, following respectively a manipulative and a mensurative approach, and focuses on changes in the taxonomic and functional composition due to river regulation and hydrological alterations. The first study, conducted in a set of seminatural streamside experimental flumes, simulates a residual flow stretch by reducing the discharge of the downstream sections (treatment) to 50% of the discharge of the upstream sections (control). Even within the short-term of our experiment (i.e., 3 weeks from the beginning of the simulation), we successfully simulated a small run-of-the river water abstraction and we recorded substantial changes in the EPT (Ephemeroptera, Plecoptera and Trichoptera) benthic assemblages. In fact, we observed shifts in functional (rather than taxonomic) EPT community composition over time, likely due to the active drift, from a typically rheophile to a more limnophile one as a response to the stress imposed by the flow reduction, related to decrease of flow. In the second study, we investigated the effectiveness of a hydropeaking mitigation measure on flow and biotic components, in a case study of hydropeaking reduction on a 10-km reach of the Noce Stream, a unique approach for Alpine streams to date. The hydrological analysis conducted applying two hydropeaking quantification indices (HP1 and HP2 of Carolli et al., 2015, and the COSH method by Sauterleute & Charmasson. 2014) confirmed a partial mitigation of the hydropeaking in the stretch. As a consequence of the change in hydrological regime, we observed a different taxonomic and functional recovery in the benthic and hyporheic communities. In fact, macrobenthos was negatively affected by the reduced dilution of point and diffuse pollution; conversely, the hyporheic communities showed an increase in diversity and abundance of interstitial taxa, especially those exclusive to the hyporheic zone, likely due to changes in the interstitial space availability, brought by a reduction of clogging caused by fine sediments which were previously released with each hydropeaking wave. The second part of the thesis is based on large dataset analysis where expert knowledge has been integrated with machine learning and data-based approaches: the focus of thesis shifts towards a holistic approach, extending the investigation to the entire watershed of the Trentino Province by including macroinvertebrate field data collected between 2009 and 2019 from 160 sampling sites, distributed over 90 rivers and streams. Based on the expertise of field operators from the local Environment Agency (APPA), and the quality indices currently used according to the Water Framework Directive (WFD), all the APPA stream sites were classified according to the presence of known hydrological, morphological, and chemical alterations, including the co-occurrence of two or more alteration types; sites in pristine conditions were also identified. Seasonality, stream order and type, and other stream characteristics associated with the elevation gradient are important in flow-ecology investigation, and for this reason were included in the analysis. Moreover, these features are proxies for other variables which are closely related with the structure of the benthic community, such as current velocity, organic matter availability and substrate composition, and can also be related to the probability of expecting the presences of small hydropower plants and/or a diffuse or localized pollution sources. This second section of the thesis is divided into two parts: the first part describes the initial overall qualitative and quantitative analysis, which was conducted to determine to which extent a functional diversity-based approach better recognizes patterns in the benthic community compared to the WFD diversity indices. The second part describes the machine learning approach which we used to examine the degree to which a-priori expert classification matched data-driven classification based on the taxonomic and functional composition of benthic macroinvertebrates across different binary classification disturbances. A Random Forest analysis was performed independently on benthic-macroinvertebrate abundance (expressed as number of individuals per m2) and their functional compositions. The majority of stream sites were a-priori classified as impacted by either one or a combination of anthropogenic alterations (80%), with only 16% of sites in reference or pristine conditions. We observed high variability in benthic community assemblages, likely due to complex environmental interactions and caused by the cumulative/synergic effect of different alterations that negatively affect the discrimination between stressor-specific responses. The overall results of these large-dataset based analyses showed relevant outcomes, the main one being the good discrimination of unaltered sites from the altered ones, but a low discriminating power for the types of alteration (hydrological, morphological, pollution pf combination of two or three of them) based on taxonomic and functional composition of the benthic communities. The functional parameters directly related to the stream longitudinal preference, microhabitat preferences, flow velocity, hydrological and thermal regime, and food availability in the river network, well the most suitable to identify any type of river degradation. A further step in the detection of significant indicator taxa/traits was achieved with the machine learning approach, which resulted in robust and dependable predictive models, that identified the specific taxa and traits related to different stressors, thus representing a promising tool to support environmental assessment and water management. Overall, this thesis contributes to the identification of appropriate indicators based on macroinvertebrates taxonomic and functional sensitivity to different specific stressors, to use in the assessment of the Ecological Status of streams in mountain areas, with relevant outcomes for the water management of Alpine running waters, with particular regard to the definition of environmental flows, and to the mitigation of hydropeaking.
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2

VALLEFUOCO, FRANCESCA. "Advancing quantitative understanding of flow-ecology relations in Alpine rivers." Doctoral thesis, country:IT, 2022. http://hdl.handle.net/10449/76097.

Повний текст джерела
Анотація:
Anthropic impacts adversely affect the productivity, integrity, connectivity, and resilience of riverine ecosystems, with widespread cumulative effects on the biota and biodiversity. The natural flow regime is a fundamental driver of physical and chemical processes, determining the morphological profile of the river systems and sustaining the complex network of ecological interactions and biological patterns. Therefore, in order to reach the environmental goals required by the binding legislation, and achieve a sustainable use of water resources, it is urgent to understand the mechanisms behind changes in the structure of biological communities along gradients of human disturbances which affect the flow regime. Indicators based on macroinvertebrates are widely used to assess the ecological status of water bodies, given their sensitivity/tolerance to pollution. However, in Alpine running waters, where chemical quality is less impacted than in lowland rivers, it is particularly important and valuable to detect the hydromorphological alterations, and to discriminate them from chemical degradation, based on the responses of benthic macroinvertebrates to such multiple stressors. Therefore, this thesis aims at: i) examining the taxonomic and functional responses of macroinvertebrate communities to the different anthropogenic pressures acting on river systems; ii) evaluating the taxa/functional traits which mostly discriminate between hydrological and morphological alterations, and chemical degradation, to support effective bioindication methods. Focus of the research is to assess the macroinvertebrate community responses to the alterations caused by flow regulation and morphological alterations, which include water abstraction, diversion, stocking and the intermittent release of water from hydropower plants, banks artificialization and construction of weirs, dams, and other structures, each of these with environmental consequences of different scale and magnitude, such as the interruption of the longitudinal continuity, residual flow release and hydropeaking. The first part of this thesis is based on two empirical field studies, following respectively a manipulative and a mensurative approach, and focuses on changes in the taxonomic and functional composition due to river regulation and hydrological alterations. The first study, conducted in a set of seminatural streamside experimental flumes, simulates a residual flow stretch by reducing the discharge of the downstream sections (treatment) to 50% of the discharge of the upstream sections (control). Even within the short-term of our experiment (i.e., 3 weeks from the beginning of the simulation), we successfully simulated a small run-of-the river water abstraction and we recorded substantial changes in the EPT (Ephemeroptera, Plecoptera and Trichoptera) benthic assemblages. In fact, we observed shifts in functional (rather than taxonomic) EPT community composition over time, likely due to the active drift, from a typically rheophile to a more limnophile one as a response to the stress imposed by the flow reduction, related to decrease of flow. In the second study, we investigated the effectiveness of a hydropeaking mitigation measure on flow and biotic components, in a case study of hydropeaking reduction on a 10-km reach of the Noce Stream, a unique approach for Alpine streams to date. The hydrological analysis conducted applying two hydropeaking quantification indices (HP1 and HP2 of Carolli et al., 2015, and the COSH method by Sauterleute & Charmasson. 2014) confirmed a partial mitigation of the hydropeaking in the stretch. As a consequence of the change in hydrological regime, we observed a different taxonomic and functional recovery in the benthic and hyporheic communities. In fact, macrobenthos was negatively affected by the reduced dilution of point and diffuse pollution; conversely, the hyporheic communities showed an increase in diversity and abundance of interstitial taxa, especially those exclusive to the hyporheic zone, likely due to changes in the interstitial space availability, brought by a reduction of clogging caused by fine sediments which were previously released with each hydropeaking wave. The second part of the thesis is based on large dataset analysis where expert knowledge has been integrated with machine learning and data-based approaches: the focus of thesis shifts towards a holistic approach, extending the investigation to the entire watershed of the Trentino Province by including macroinvertebrate field data collected between 2009 and 2019 from 160 sampling sites, distributed over 90 rivers and streams. Based on the expertise of field operators from the local Environment Agency (APPA), and the quality indices currently used according to the Water Framework Directive (WFD), all the APPA stream sites were classified according to the presence of known hydrological, morphological, and chemical alterations, including the cooccurrence of two or more alteration types; sites in pristine conditions were also identified. Seasonality, stream order and type, and other stream characteristics associated with the elevation gradient are important in flow-ecology investigation, and for this reason were included in the analysis. Moreover, these features are proxies for other variables which are closely related with the structure of the benthic community, such as current velocity, organic matter availability and substrate composition, and can also be related to the probability of expecting the presences of small hydropower plants and/or a diffuse or localized pollution sources. This second section of the thesis is divided into two parts: the first part describes the initial overall qualitative and quantitative analysis, which was conducted to determine to which extent a functional diversitybased approach better recognizes patterns in the benthic community compared to the WFD diversity indices. The second part describes the machine learning approach which we used to examine the degree to which a-priori expert classification matched data-driven classification based on the taxonomic and functional composition of benthic macroinvertebrates across different binary classification disturbances. A Random Forest analysis was performed independently on benthicmacroinvertebrate abundance (expressed as number of individuals per m2) and their functional compositions. The majority of stream sites were a-priori classified as impacted by either one or a combination of anthropogenic alterations (80%), with only 16% of sites in reference or pristine conditions. We observed high variability in benthic community assemblages, likely due to complex environmental interactions and caused by the cumulative/synergic effect of different alterations that negatively affect the discrimination between stressor-specific responses. The overall results of these large-dataset based analyses showed relevant outcomes, the main one being the good discrimination of unaltered sites from the altered ones, but a low discriminating power for the types of alteration (hydrological, morphological, pollution pf combination of two or three of them) based on taxonomic and functional composition of the benthic communities. The functional parameters directly related to the stream longitudinal preference, microhabitat preferences, flow velocity, hydrological and thermal regime, and food availability in the river network, well the most suitable to identify any type of river degradation. A further step in the detection of significant indicator taxa/traits was achieved with the machine learning approach, which resulted in robust and dependable predictive models, that identified the specific taxa and traits related to different stressors, thus representing a promising tool to support environmental assessment and water management. Overall, this thesis contributes to the identification of appropriate indicators based on macroinvertebrates taxonomic and functional sensitivity to different specific stressors, to use in the assessment of the Ecological Status of streams in mountain areas, with relevant outcomes for the water management of Alpine running waters, with particular regard to the definition of environmental flows, and to the mitigation of hydropeaking.
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3

McManamay, Ryan A. "Providing a Restoration Framework for Regulated Rivers." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/77088.

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With over 800,000 dams occurring globally and the construction of thousands more being proposed, successful restoration of regulated rivers will depend on the creation of broadly applicable frameworks that provide management solutions by generalizing patterns in habitat and ecology. Based on the prevailing scientific literature, restoring natural stream flows in disturbed rivers is dependent upon developing quantitative, transferable stream flow-ecology relationships. The purpose of my dissertation was to apply a framework to regulated and unregulated streams within an eight-state region of the southeastern US to test its ability to generalize patterns in natural and altered stream flow and develop flow-ecology relationships. I created a simplified, 5-step version of the Ecological Limits of Hydrologic Alteration (ELOHA) framework (Poff et al. 2010). I carried out each of the steps in sequential order for unregulated and dam-regulated streams found in my region. The steps of my restoration framework are as follows:
  1. Develop a natural flow classification of unregulated streams
  2. Develop a tool that uses landscape characteristics to predict flow class membership
  3. Use the predictive tool or pre-disturbance hydrologic information to classify regulated rivers to natural flow classes
  4. Based on class membership, generalize patterns in hydrologic alteration
  5. Relate ecological patterns to patterns in hydrologic alteration in relation tomorphology, temperature, and landscape disturbance
Altogether, the results of steps 1-4 suggest that patterns in natural flow dynamics and hydrologic alterations can successfully be placed within a framework and generalized to provide the basis and context for environmental flow management; however, results of step 5 suggest that patterns in flow alteration were poorly related to fish assemblages relative to channel morphology, habitat fragmentation, temperature, and substrate. Thus, the development of patterns in hydrologic alteration using the existing frameworks (including mine) may not be ecologically-relevant. My results suggest that current regulated river restoration should not be dependent upon the development of flow-ecology relationships alone, but the interaction between flow, morphology, and temperature within a landscape disturbance context. These relationships should be incorporated within a hierarchical framework to guide restoration efforts in regulated rivers in the future.
Ph. D.
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4

Bleby, Timothy Michael. "Water use, ecophysiology and hydraulic architecture of Eucalyptus marginata (jarrah) growing on mine rehabilitation sites in the jarrah forest of south-western Australia." University of Western Australia. School of Plant Biology, 2003. http://theses.library.uwa.edu.au/adt-WU2004.0004.

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[Truncated abstract. Please see the pdf format for the complete text. Also, formulae and special characters can only be approximated here. Please see the pdf version for an accurate reproduction.] This thesis examines the water use, ecophysiology and hydraulic architecture of Eucalyptus marginata (jarrah) growing on bauxite mine rehabilitation sites in the jarrah forest of south-western Australia. The principal objective was to characterise the key environment and plant-based influences on tree water use, and to better understand the dynamics of water use over a range of spatial and temporal scales in this drought-prone ecosystem. A novel sap flow measurement system (based on the use of the heat pulse method) was developed so that a large number of trees could be monitored concurrently in the field. A validation experiment using potted jarrah saplings showed that rates of sap flow (transpiration) obtained using this system agreed with those obtained gravimetrically. Notably, diurnal patterns of transpiration were measured accurately and with precision using the newly developed heat ratio method. Field studies showed that water stress and water use by jarrah saplings on rehabilitation sites were strongly seasonal: being greatest in summer when it was warm and dry, and least in winter when it was cool and wet. At different times, water use was influenced by soil water availability, vapour pressure deficit (VPD) and plant hydraulic conductance. In some areas, there was evidence of a rapid decline in transpiration in response to dry soil conditions. At the end of summer, most saplings on rehabilitation sites were not water stressed, whereas water status in the forest was poor for small saplings but improved with increasing size. It has been recognised that mature jarrah trees avoid drought by having deep root systems, however, it appears that saplings on rehabilitation sites may have not yet developed functional deep roots, and as such, they may be heavily reliant on moisture stored in surface soil horizons. Simple predictive models of tree water use revealed that stand water use was 74 % of annual rainfall at a high density (leaf area index, LAI = 3.1), high rainfall (1200 mm yr-1) site, and 12 % of rainfall at a low density (LAI = 0.4), low rainfall (600 mm yr-1) site, and that water use increased with stand growth. A controlled field experiment confirmed that: (1) sapling transpiration was restricted as root-zone water availability declined, irrespective of VPD; (2) transpiration was correlated with VPD when water was abundant; and (3) transpiration was limited by soil-to-leaf hydraulic conductance when water was abundant and VPD was high (> 2 kPa). Specifically, transpiration was regulated by stomatal conductance. Large stomatal apertures could sustain high transpiration rates, but stomata were sensitive to hydraulic perturbations caused by soil water deficits and/or high evaporative demand. No other physiological mechanisms conferred immediate resistance to drought. Empirical observations were agreeably linked with a current theory suggesting that stomata regulate transpiration and plant water potential in order to prevent hydraulic dysfunction following a reduction in soil-to-leaf hydraulic conductance. Moreover, it was clear that plant hydraulic capacity determined the pattern and extent of stomatal regulation. Differences in hydraulic capacity across a gradient in water availability were a reflection of differences in root-to-leaf hydraulic conductance, and were possibly related to differences in xylem structure. Saplings on rehabilitation sites had greater hydraulic conductance (by 50 %) and greater leaf-specific rates of transpiration at the high rainfall site (1.5 kg m-2 day1) than at the low rainfall site (0.8 kg m-2 day1) under near optimal conditions. Also, rehabilitation-grown saplings had significantly greater leaf area, leaf area to sapwood area ratios and hydraulic conductance (by 30-50 %) compared to forest-grown saplings, a strong indication that soils in rehabilitation sites contained more water than soils in the forest. Results suggested that: (1) the hydraulic structure and function of saplings growing under the same climatic conditions was determined by soil water availability; (2) drought reduced stomatal conductance and transpiration by reducing whole-tree hydraulic conductance; and (3) saplings growing on open rehabilitation sites utilised more abundant water, light and nutrients than saplings growing in the forest understorey. These findings support a paradigm that trees evolve hydraulic equipment and physiological characteristics suited to the most efficient use of water from a particular spatial and temporal niche in the soil environment.
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5

MinCheng and 鄭閔. "The Basin-scale Optimal Operating Strategies for Incorporating Ecology- Flow Relationship in Hsintien Creek Basin, Taiwan." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/59219205658961127915.

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碩士
國立成功大學
水利及海洋工程學系
104
Water-resources developments such as impoundment and streamflow diversion by water-resources facilities would alter streamflow natural variability and threaten ecosystem diversity and riverine health. Finding a balance between human and environmental needs becomes a challenge task in water-resources management. In this study, a relationship between ecological indicators and hydrological indicators are constructed by multiple linear regression. This relationship is incorporated into a basin-scale model and applied to Hsintien Creek basin located in northern Taiwan to derive the optimal operating strategies. The sampled macroinvertebrates data at various sites are transformed into ecological indicators which include Margalet’s diversity index, Shannon-Wiener’s diversity index and Pielou’s evenness index. A total of 8 human indicators are used to evaluate performance of water-resources facilities for water supply, hydropower generation, and flood mitigation. These two types of indicators are integrated into an overall indicator using technique for order performance by similarity to ideal selection (TOPSIS) to derive the optimal operating strategies. The results show that the current scenario is slightly better than the no environmental flow scenario. The optimal scenario has great improvements in most of human indicators and reduce hydrologic-alteration impacts.
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Книги з теми "Flow-ecology relationship"

1

1963-, Inderjit, Dakshini, K. M. M., 1934-, and Foy Chester L, eds. Principles and practices in plant ecology: Allelochemical interactions. Boca Raton, FL: CRC Press, 1999.

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2

Crowe, C. T. Multiphase flows with droplets and particles. Boca Raton, Fla: CRC Press, 1998.

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3

Crowe, C. T. Multiphase flows with droplets and particles. Boca Raton, Fla: CRC Press, 1998.

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4

Clarke, Andrew. Principles of Thermal Ecology: Temperature, Energy, and Life. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199551668.001.0001.

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Temperature affects everything. It influences all aspects of the physical environment and governs any process that involves a flow of energy, setting boundaries on what an organism can or cannot do. This novel textbook explores the key principles behind the complex relationship between organisms and temperature, namely the science of thermal ecology. It starts providing a rigorous framework for understanding the nature of temperature and the flow of energy in and out of the organism, before describing the influence of temperature on what organisms can do, and how fast they can do it. Central to this is the relationship between temperature and metabolism, which then forms the basis for an exploration of the effects of temperature on growth and size. Two chapters cover first endothermy (including how this expensive lifestyle might have evolved), and then when and how this is suspended in torpor and hibernation. With these fundamental principles covered, the book’s final section explores thermal ecology itself, incorporating the important extra dimension of interactions with other organisms. After an examination of the relationship between temperature, energy and diversity, an entire chapter is devoted to the crucially important subject of the nature of climate change and how organisms are responding to this. Throughout the book, emphasis is placed on the need for an understanding of the underlying physical mechanisms, and the important insights that can be gained from the historical and fossil record.
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5

With, Kimberly A. Essentials of Landscape Ecology. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198838388.001.0001.

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Essentials of Landscape Ecology is a new, comprehensive text that presents the principles, theory, methods, and applications of landscape ecology in an engaging and accessible format, supplemented by numerous examples and case studies from a variety of systems, including freshwater and marine “scapes.” Human activity has transformed landscapes worldwide on a scale that rivals or exceeds even the largest of natural forces, giving rise to a new geological age, the Anthropocene. As humans alter the structure and function of landscapes, the biological diversity and ecological relationships within those landscapes are also inevitably altered, to the extent that this may interfere with humanity’s efforts to sustain the productivity and multifunctional use of these landscapes. Landscape ecology has thus emerged as a new, multidisciplinary science to investigate the effects of human land use and environmental heterogeneity on ecological processes across a wide range of scales and systems: from the effects of habitat or resource distributions on the individual movements, gene flow, and population dynamics of plants and animals; to the human alteration of landscapes affecting the structure of biological communities and the functioning of entire ecosystems; to the sustainable management of natural resources and the ecosystem goods and services upon which society depends.
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6

(Editor), Inderjit, K. M. M. Dakshini (Editor), and Chester L. Foy (Editor), eds. Principles and Practices in Plant Ecology: Allelochemical Interactions. CRC, 1999.

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Частини книг з теми "Flow-ecology relationship"

1

Solera, Agustina, and Mariana Jesús Ortecho. "The Territory of Our Body: A Conversation on Urban Environments in the Andes and Their Bodies." In Contours of Feminist Political Ecology, 289–310. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-20928-4_12.

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AbstractIn this chapter, we dialogically intertwine meanings that flow between the Western and the Andean cultural horizons, in urban environments marked by coloniality. Attentive to different ways of establishing community, we evoke elements from the Andean worldview from a decolonial perspective, at times overlapping with feminist political ecology (FPE). By opening to the Andean way of understanding and feeling the relationship between the social and the natural, we rehearse answers to social and environmental crises.
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2

Pérez-Rincón, Mario Alejandro. "Materials Flow Analysis in Latin America." In Studies in Ecological Economics, 123–35. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-22566-6_11.

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AbstractBased on a systematic and organized literature review, the academic production for Latin America and the Caribbean (LAC) on Material Flow Analysis (MFA) was evaluated. This allowed us to know the research developments and to identify the influence of the “Barcelona School” (EB) and Professor Joan Martínez-Alier in this field of work in the region. The general balance of the literature reviewed (47 texts), shows the important influence of the EB for LAC: more than half of the publications have its origin, more than a third correspond to doctoral theses linked to the ICTA-UAB and 30% are published in journals originating in the ICTA-UAB. Thematically, the articles evaluated incorporate the main topics promoted by the EB. They are oriented towards studying the relationships between the metabolic dynamics of economies, environmental pressures and liabilities, and ecological distributive conflicts. These orientations correspond precisely to Professor Martínez-Alier’s central field of work: the link between ecological economics and political ecology. Methodologically, the potential and weaknesses of MFA were identified. Long-term material flow series have the potential to study large material-economic transitions, but little depth. Short and more detailed series, combining MFA with other methodologies, allow to better delve into the black box of energy-material flows and the environmental impacts of economic dynamics.
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3

Lopa, R., and Y. Shimatani. "Relationship between scenery of flow ecology habitat and physical environment." In River Flow 2014, 2331–38. CRC Press, 2014. http://dx.doi.org/10.1201/b17133-311.

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4

"Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques." In Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques, edited by Gary D. Grossman and John L. Sabo. American Fisheries Society, 2010. http://dx.doi.org/10.47886/9781934874141.ch20.

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<em>Abstract.—</em>Stochastic dynamics are central to theory, data analysis, and understanding in the fields of hydrology and population ecology. More importantly, hydrologic variability has been identified as a key process affecting biodiversity and coexistence in stream fish assemblages. Until recently, however, we have lacked tools by which hydrologic variability can be directly linked to measures of community stability. Herein, we show how a modification of Fourier analysis of daily average discharge data can be used to quantify aspects of hydrologic variability for three reference streams and then linked to measures of fish assemblage stability in Coweeta Creek, North Carolina; Sagehen Creek, California; and Otter Creek, Indiana) via multivariate autoregressive (MAR) models. Specifically, we define the magnitude of catastrophic variability as the standard deviation of <em>residual </em>flows referenced to a long-term annual trend, and individual catastrophic events as flows greater than (floods) or less than (droughts) two times this magnitude (i.e., 2 𝛔). We then directly link the magnitude of annual <em>residual </em>flows with MAR models that quantify the relationship between flows and the stability of fish assemblages from the same or nearby streams. Our results confirm that these streams represent a gradient in the stability properties of fish assemblages; Sagehen Creek is the most stable, whereas Otter Creek is the least stable. The timing of catastrophic high and low flows is most predictable in Sagehen Creek and least predictable in Big Raccon Creek (reference stream for Otter Creek), whereas the magnitude and frequency of <em>catastrophic </em>events varied in a manner less consistent with the gradient in fish community stability. Nevertheless, the stability of fish communities covaried significantly with both residual flow magnitudes (high- and low-flow events). Although this technique is not without limitations (e.g., it is most relevant to resident species), it appears to be a promising new tool for linking hydrologic variability directly to fish assemblage stability and, more broadly, for quantifying links between flow regulation and the viability of native aquatic faunas.
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5

Altuntas, Ozlem. "Production of Vegetable Crops by Using Arbuscular Mycorrhizae." In Mycorrhizal Fungi - Utilization in Agriculture and Industry [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.97552.

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In modern agriculture, application of beneficial microorganisms has become more reliable and alternative source to reduce the application of pesticides. Several studies demonstrate that the beneficial microorganisms like arbuscular mycorrhizal (AM) fungi, Pseudomonas species, Trichoderma species etc. increase the plant growth and their and also improve the quality of soil. Additionally, these microorganisms increase the resistance of host plants against biotic and abiotic stresses. In the present chapter; vegetable crops in horticultural systems were focused. Most of the vegetable crop form symbiotic relationship with mycorrhiza acting as a bridge for the flow of energy and matter between plants and soils. The symbiotic relationship includes most species of vegetables and some species of fungi that have great relevance to soil ecosystem functions, especially nutrient dynamics, microbial processes, plant ecology, and agriculture. AMF can improve the nutrient and water uptake, induce tolerance of abiotic and biotic stress of their host plants. In the sustainable agriculture, the association of soil microorganisms with plant roots can also be exploited and in this way improve plant growth and productivity under normal and stressful environment. As a result, mycorrhizae improves plant growth, root structure development and crop yield and quality in almost any ambient condition. In addition, another benefit of mycorrhizae is that plants are resistant to diseases. it is concluded that arbuscular mycorrhizal infused pepper seedlings have high yield and quality. And also arbuscular mycorrhizae can be recommended for high yield and quality crop.
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6

Waide, Robert, and Peter M. Groffman. "Unified Framework II Ecosystem Processes: A Link Between Species and Landscape Diversity." In Biodiversity in Drylands. Oxford University Press, 2005. http://dx.doi.org/10.1093/oso/9780195139853.003.0019.

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The discipline of ecology can be subdivided into several subdisciplines, including community, ecosystem, and landscape ecology. While all the subdisciplines are important to the study of biodiversity, there is great variation in the extent to which their contributions have been analyzed. For example, the role of community ecology in biodiversity studies is well established. In community ecology, the entities of study are species that differ in their properties and generate a web of interactions that, in turn, organize the species into a community. Similar to community ecology, the contribution of landscape ecology to biodiversity is apparent. The entities of study, definable “patches,” are tangible. They differ in their properties and generate a web of interactions that organize the patches into a landscape mosaic. In contrast to community and landscape ecology, the role of ecosystem ecology in biodiversity is less apparent. In ecosystem ecology, it often is not clear what the entities are, and how they are organized. To the extent that ecosystem ecology focuses on energy flow and nutrient cycling, we can define fundamental entities as compartments and vectors in models that depict the flows of water, energy, and nutrients through communities. If we apply diversity criteria to these entities, we can use the term ecosystem diversity to refer to the number of compartments and vectors, the differences among them in type and size, and their organization in promoting energy flow or nutrient cycling. To our knowledge, ecosystem scientists have not yet developed criteria for ecosystem diversity similar to those used for species and landscape diversity. There has been some use of the term “ecosystem diversity” to refer to a diversity of ecosystems, implying a variety of habitats, landscapes, or biomes. As discussed above, we suggest that to define the role of ecosystem ecology in biodiversity studies, the approach should be to study the relationships among species, landscape, and ecosystem diversities (chapters 1 and 13). However, since the concept of ecosystem diversity awaits further development, we adopt a different approach for understanding the role of ecosystem science in biodiversity studies. In this chapter, we examine relationships among ecosystem processes, species diversity, and landscape diversity.
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7

"Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques." In Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques, edited by Gary D. Grossma, Robert E. Ratajczak, Mark D. Farr, C. Michael Wagner, and J. Todd Petty. American Fisheries Society, 2010. http://dx.doi.org/10.47886/9781934874141.ch4.

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<em>Abstract</em>.—Studies demonstrating the mechanisms regulating biodiversity are uncommon. Streams and rivers worldwide display a longitudinal gradient in fish biodiversity, and most prior research has used correlative evidence to infer that higher downstream diversity is produced by factors facilitating greater niche separation. We combine 20 years of fish abundance samples from a representative southern Appalachian stream with critical swimming velocity experiments to provide direct evidence that a shifting hydrodynamic barrier affects this gradient in Coweeta Creek. We observed increased diversity in multiple sites, produced by species immigrating upstream during periodic droughts (1985–1988, 1999–2002) and a highly significant positive relationship (<em>r<sup></em>2</sup> = 0.77) between drought (Palmer index) and Shannon-Weiner diversity. Resident fish generally had smaller standard lengths during drought periods. Critical velocity measurements showed that residents could tolerate faster water velocities than drought immigrants and that upstream velocities in nondrought years were faster than those in some downstream sites. These data support the hypothesis that local fish diversity in this system is limited by the ability of drought immigrants to pass an upstream hydrodynamic barrier. Alternative hypotheses such as temperature differences between sites, increased capture efficiency during droughts, and increased productivity during droughts were not supported by the data. The relationship between drought and diversity in this system is counterintuitive because drought should reduce resource availability and produce lower rather than higher diversity. These results highlight the important relationship between natural flow variation and maintenance of local diversity and demonstrate the need for long-term ecological data.
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8

"Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques." In Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques, edited by Marlis R. Douglas and Michael E. Douglas. American Fisheries Society, 2010. http://dx.doi.org/10.47886/9781934874141.ch8.

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<em>Abstract</em>.—Our capabilities to address pertinent questions in stream fish ecology, such as population connectivity, biotic homogenization, species invasions, introgression, and effects of habitat alterations on population structure and demography, have been significantly expanded by the development of molecular genetic approaches. A broad spectrum of molecular markers can now be tailored to address specific questions while newer statistical approaches accommodate larger data sets and permit the test of alternative hypotheses. Furthermore, molecular approaches facilitate the evaluation of ecological processes across both spatial and temporal scales, which are often mutually exclusive parameters. Population expansions, declines, and movements can be examined from recent to deep history and scaled from local to continental drainages. The intrinsic properties of stream ecosystems also make them particularly amenable to molecular approaches. The hierarchical order reflected in streams is directly translatable into an expanding spatial scale, from restricted headwaters through entire basins. Additionally, stream habitats are generally linear, and consequently, fish populations are often distributed sequentially, with interactions constrained to neighboring populations. Finally, streams tend to develop vicariant barriers over time, thus isolating populations and promoting local adaptation, a process easily deciphered using molecular markers. The latter have also contributed to the resolution of conservation issues and guided appropriate adaptive management of stream fauna. Molecular approaches in stream fish ecology are far too diverse to be comprehensively reviewed herein. Instead, we illustrate their facility by emphasizing three case studies demonstrating their broad utility: (1) a range-wide analysis of mitochondrial DNA diversity in flannelmouth sucker <em>Catostomus latipinnis</em>, pointing to a population bottleneck likely induced by severe post-Pleistocene drought in the Colorado River basin; (2) single nucleotide polymorphism screening to evaluate hybridization and introgression among native flannelmouth sucker, bluehead sucker <em>C. discobolus </em>(also known as <em>Pantosteus discobolus</em>), and the introduced white sucker <em>C. commersonii </em>in the upper Colorado River basin; and (3) microsatellite DNA analysis to evaluate gene flow and contemporary relationships in the Grand Canyon among populations of an endangered cyprinid fish (the humpback chub <em>Gila cypha</em>). In an appendix, we outline several recent molecular approaches that have expanded our opportunities to study stream fish ecology. We review relevant literature by emphasizing new statistical approaches and potential pitfalls of marker selection and data, rather than by delving into abstruse technical details regarding protocol development.
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9

Thompson, John N. "The Geographic Dynamics of Coevolution." In Evolutionary Ecology. Oxford University Press, 2001. http://dx.doi.org/10.1093/oso/9780195131543.003.0032.

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Coevolution is reciprocal evolutionary change in interacting species driven by natural selection. It is a pervasive evolutionary process that has shaped many of the major events in the history of life, including the origin of the eukaryotic cell, the origin of plants, the evolution of coral reefs, and the formation of lichens, mycorrhizae, and rhizobia, all of which are crucial in the development of terrestrial communities. Just as important, evidence is increasing that Coevolution is an important ongoing ecological process, continually shaping and reshaping interactions among species, sometimes over time spans of only a few decades. This chapter is an evaluation of coevolution as an ongoing process shaped by the geographic structure of interactions among species. It is an analysis of what we have learned recently as we have taken a broader geographic view of how coevolution continually remolds the relationships among taxa. The first mathematical models of geographically structured coevolution were developed only in the past few years, and there are still fewer than a dozen empirical studies that have analyzed any aspects of coevolutionary structure and dynamics across geographic landscapes. Nevertheless, these theoretical and empirical studies have together suggested that coevolution is very likely a much more dynamic process than suggested by the previous several decades of study in evolutionary ecology. Coevolution is a hierarchical process. Local populations of species interact with one another and sometimes coevolve. These local populations are in turn connected through gene flow to populations in other communities, and this geographic structuring adds another level to the coevolutionary process. Local geographic clusters of populations may show metapopulation dynamics, and yet broader geographic groupings of populations may show considerable genetic differentiation in the traits of interacting species. Only a subset of locally or regionally coevolving traits will eventually sweep through all populations. Hence, coevolution as seen in comparisons of interacting phylogenetic lineages will show only a small fraction of the Coevolutionary dynamics found at the population, metapopulation, and broader geographic scales. Within this hierarchical structure of coevolution, many of the dynamics may occur above the level of local populations and below the level of the fixed traits of species for three reasons: Many species are collections of genetically differentiated populations, the outcomes of species interactions commonly differ among communities, and interacting species often do not have identical geographic ranges.
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Тези доповідей конференцій з теми "Flow-ecology relationship"

1

Layton, Astrid, Bert Bras, and Marc Weissburg. "Designing Sustainable Manufacturing Networks: The Role of Exclusive Species in Achieving Ecosystem-Type Cycling." In ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/detc2017-68334.

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Ecology is proving to be an innovative source for design principles. Studies have examined how ecological principles can enhance sustainability in industrial networks. Ecologically-inspired manufacturing networks tend to focus on supporting symbiotic relationship formation, creating a cyclical flow structure that has been shown to result in efficiency and resource consumption improvements. Despite successes, bio-inspired manufacturing networks still fail to accurately mimic ecosystem cycling. The roles of exclusive actors and specialized predators in achieving the high cycling characteristic of ecosystems is investigated here. Exclusive actors participate in the network as either only a consumer (predator) or only a producer (prey). Specialized predators consume only one producer inside the system boundary. The populations of these special actors in manufacturing networks versus ecological food webs speaks to the potential influence these roles have on the cycling the network achieves. The trends shown here suggest less exclusivity is necessary for achieving ecologically-strong network cycling.
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2

Shi, Xiang, Julia R. de Rezende, and Kenneth Sorbie. "Microbial Ecology Metrics to Assess the Effect of Biocide on Souring Control and Improve Souring Modelling." In SPE International Oilfield Corrosion Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/205037-ms.

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Abstract Reservoir souring is a long-standing issue for the oil and gas industry caused by sulfate-reducing microorganisms (SRM) producing H2S from sulfate ions. In this work, we investigated the connections between the development of souring and the change in three key microbial ecology metrics: the abundance, alpha diversity and community structure of a souring microbiota under the biocide treatment of 100 ppm glutaraldehyde (henceforth referred to as GA). These are studied in sand-packed flow-through bioreactors during and after the biocide treatment using cutting-edge DNA assays. Our study suggests that the rebound of microbial sulfide production after the 100 ppm GA treatment is closely associated with the recovery in microbial abundance and microbial alpha diversity. The study also shows that 100 ppm GA treatment may lead to a measurable shift in the SRM community structure. By comparing the effluent microbial community with the sand microbial community, the study suggests that the change in alpha diversity of the produced water microbial community might be an early warning for the sulfide breakthrough due to souring recurrence in practice. This work explores the relationship between souring and the underlining microbial community behaviours in response to the 100 ppm GA treatment and, to characterise these changes, we propose measurable metrics. A conceptual model is also proposed describing the near-term biological process behind the biocide treatment-recovery cycle in a souring scenario. Finally, this work highlights the potential applications and caveats of harnessing the increasingly available field microbial community data for the improvement of souring modelling and field souring control strategies.
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3

Layton, Astrid, Bert Bras, and Marc Weissburg. "Ecological Robustness as a Design Principle for Sustainable Industrial Systems." In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/detc2015-47560.

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Ecology has acted as a source for sound design principles and studies have examined how ecological principles can enhance sustainability in human industrial networks. Engineered systems are often designed for maximum performance, but in many cases robustness is sought with respect to unwanted variations in input or other parameters. Taguchi’s signal to noise ratio and other quality engineering principles are well known fundamentals in the field of robust design. In this paper, we will introduce flow-based equations from ecological network analysis (ENA) to determine how to modify the flows and connections in industrial systems to balance efficiency and robustness against disturbances. In ENA, the robustness of a system is given by the relationship of flow path diversity to system efficiency. Systems with diverse flows are more resilient to a disturbance since there are redundant pathways, but are inefficient precisely because they contain many flow paths with the same endpoints. Efficient systems have increased capacity to transfer material and energy, but this is at the cost of fewer pathways so the system is brittle. Thus, given a disturbance, a robust system balances redundancy with efficiency/capacity. Ecological systems seem to occupy a narrow range of states that balance efficiency and resilience to confer robustness. Human networks, like trade networks, water reclamation facilities, etc. have been analyzed using these robustness principles and methods for flow based ecological network analysis. These analyses show that human networks may be more brittle than their ecological counterparts because of insufficient flow path diversity.
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Panyam, Varuneswara, Tirth Dave, and Astrid Layton. "Understanding Ecological Efficiency and Robustness for Network Design Using Thermodynamic Power Cycles." In ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85404.

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Ecology has acted as a source for sound design principles and studies of ecosystems have examined how ecological principles can enhance sustainable human network design. Engineered systems are often designed for maximum performance, but in many cases, robustness is lost due to unwanted variations in inputs or efficiency. Taguchi’s signal to noise ratio and other quality engineering principles are well known fundamentals in the field of robust design. In this paper, we will introduce flow-based metrics from ecological network analysis (ENA) for robustness, efficiency, and redundancy. Ecosystem robustness is related to the balance between flow path diversity and system delivery efficiency. Systems with diverse flows are more resilient to a disturbance since there are redundant pathways, but are inefficient because they contain many flow paths with the same endpoints. Efficient systems are better able to transfer material and energy, but this is at the cost of fewer pathways so the system is brittle. Thus to survive a disturbance, an ecosystem system balances redundancy with efficiency. Thermodynamic power cycles are used to understand the relationship between energy efficiency, measured using first law efficiency, and ecological robustness and an ecological balance of efficiency to redundancy (as measured by ascendency vs development capacity). The result highlights the importance of understanding differences in the meaning of efficiency between two fields, and that from an engineering standpoint robustness does not have to be sacrificed to obtain energy efficiency.
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5

Lin, Zhongjie. "Vertical Urbanism: Re-conceptualizing the Compact City." In 2016 ACSA International Conference. ACSA Press, 2016. http://dx.doi.org/10.35483/acsa.intl.2016.26.

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Although the term “compact city” appears frequently in academic accounts on sustainable urbanism as well as in professional descriptions of planning projects, it is often used in a general manner to indicate such ideas as high density, mixed uses, walkability, and transit oriented development, all linking to the common principles of New Urbanism. Unfortunately this misses some important points, as the concept of compact city possesses the power to generate dynamic urban forms, utilize cutting-edge technologies, address pressing environmental issues, and respond to distinctive geographical and cultural contexts, thus challenging conventional notions of urbanism. The awareness of the limitations of the current practice leads to the introduction of Vertical Urbanism as an alternative discourse on the compact city responding proactively to the state of contemporary metropolises characterized by density, complexity, and verticality. The reinvented concept of Vertical Urbanism moves away from the Modernist notion promoting tall buildings as dominant urban typology to explore physically interactive and socially engaged forms addressing the city as a multi-layered and multi-dimensioned organism. Informed by complex systems ranging from underground mass transit to futuristic ecology of vertical urban farm, this experimental urban design approach envisions a holistic organization of infrastructure, space, and ecology ina three-dimensional framework. This paper derives from a series of urban design research studios under the common theme of Vertical Urbanism conducted in four different cities in the United States and China during 2010-2014 and recently shifted to Rio de Janeiro in Brazil. These studio stook on various sites and design questions such as urban infrastructure, transit system, and urban waterfront redevelopments, testing the concept in different geographic and cultural settings. Sensitivity to locality in both ecological and cultural terms was emphasized across these studios although the schemes often engaged speculative and innovative modes of design production. This paper examines a number of issues around the urban design approach of Vertical Urbanism, including the drive for density and vitality, the relationship between horizontal and vertical dimensions, space of flow and scalar shift, as well as ecological and social adaptability of mega forms; but above all, it tries to explore the capacity of global urban tactics in providing localized design solutions.
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Adams, Daniel, and Marie Law Adams. "Resource Industries in the Post-Industrial City." In 2016 ACSA International Conference. ACSA Press, 2016. http://dx.doi.org/10.35483/acsa.intl.2016.43.

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Resource industries are present in the post-industrial city in a mutable state, as the goods of global trade pass through as interim piles (salt, sand, and gravel), in holding tanks (petroleum), and silos (cement). The flow of resources is fundamental to urban life and shapes the urban landscape, yet engagement with this mode of industry in the city has been largely outside the realm of the design disciplines. If Reyner Banham’s Los Angeles was made legible through the mediating lens of the windshield and the rear-view mirror, then the constructed landscapes of primary resources in today’s post-industrial city are only understandable through the windshield of the front-end loader that acts as the mediator between global networks and local distribution. The material terminals that these loaders serve are not classified by permanent structures, but rather by the through put dictated by the demands of the city. This dynamic relationship of primary industry to the contemporary city is better understood through the relational terms of ecology than formal conventions of architecture. As such, the environments created by the flows of primary industry to urban centers require new modes of engagement from designers. The current architectures of such resource industries in cities- containers, sheds, fences – result from practices of use-based zoning, homeland security, and offsite mitigation, but such static structures fail to engage the dynamic dimensions of a fluid industry. In order to create a new framework, this paper analyzes the spatial and programmatic opportunities that result from re-conceiving these three regulatory conventions through an analysis of a realized project with a global marine terminal in Boston Harbor.
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Звіти організацій з теми "Flow-ecology relationship"

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Vernon, Christopher R., Evan V. Arntzen, Marshall C. Richmond, R. A. McManamay, Timothy P. Hanrahan, and Cynthia L. Rakowski. GIS Framework for Large River Geomorphic Classification to Aid in the Evaluation of Flow-Ecology Relationships. Office of Scientific and Technical Information (OSTI), February 2013. http://dx.doi.org/10.2172/1079745.

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