ASSESSMENT OF THE LEVEL OF STRESS ON PLANTS OF WESTERN SIBERIAN RAISED BOGS BY THE METHOD OF FRACTAL ANALYSIS

Sufficient evidence has been collected that alternative biological and ecological processes may occur in individual plant specimens that dwell in environmentally equivalent habitats. Environmental stress triggers individual, specimen-specific adaptive response. The paper shows how fractal analysis can be used to study the degree of stress that plants in different habitats and environmental factor combinations are exposed to.

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Human shoreline development and the nutrient stoichiometry of aquatic plant communities in Canadian Shield lakes

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f2012-080 ◽

2012 ◽

Vol 69 (10) ◽

pp. 1642-1650 ◽

Cited By ~ 17

Author(s):

Paul C. Frost ◽

Andrea L. Hicks

Keyword(s):

Elemental Composition ◽

Plant Communities ◽

Aquatic Plant ◽

Taxonomic Composition ◽

Individual Plant ◽

Nutrient Stoichiometry ◽

Shoreline Development ◽

Ecological Processes ◽

South Central ◽

Littoral Zones

Human activities associated with residential development potentially alter ecological processes in lake littoral zones. We determined how the nutrient stoichiometry of aquatic plant communities relates to residential density around lakes of south-central Ontario. We calculated the elemental composition of entire plant communities from multiple sites in 12 lakes using measurements of individual plant C:N:P ratios and their areal biomass. We found considerable variability in the C:N:P ratios of whole aquatic plant communities among sites and lakes, which was not accounted for by intraspecific variability in the elemental composition of aquatic plants. Instead, differences in community-level C:N:P ratios primarily resulted from high interspecific variability in the elemental composition among dominant plant taxa and variable taxonomic composition of sampled plant communities. Plant community composition differed among lakes with and without shoreline residences, and we found lower C:N and C:P ratios in communities from littoral zones in human-developed lakes. Our results thus demonstrate a link between the elemental and taxonomic composition of aquatic plant communities, which may mediate biogeochemical responses of littoral zones to development of lake shorelines.

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Pervasive and strong effects of plants on soil chemistry: a meta-analysis of individual plant ‘Zinke’ effects

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.1001 ◽

2015 ◽

Vol 282 (1812) ◽

pp. 20151001 ◽

Cited By ~ 53

Author(s):

Bonnie G. Waring ◽

Leonor Álvarez-Cansino ◽

Kathryn E. Barry ◽

Kristen K. Becklund ◽

Sarah Dale ◽

...

Keyword(s):

Soil Properties ◽

Meta Analysis ◽

Soil Heterogeneity ◽

Individual Plant ◽

Ecological Processes ◽

Plant Soil ◽

Local Soil ◽

Plant Effects ◽

Intensively Managed ◽

Managed Ecosystems

Plant species leave a chemical signature in the soils below them, generating fine-scale spatial variation that drives ecological processes. Since the publication of a seminal paper on plant-mediated soil heterogeneity by Paul Zinke in 1962, a robust literature has developed examining effects of individual plants on their local environments (individual plant effects). Here, we synthesize this work using meta-analysis to show that plant effects are strong and pervasive across ecosystems on six continents. Overall, soil properties beneath individual plants differ from those of neighbours by an average of 41%. Although the magnitudes of individual plant effects exhibit weak relationships with climate and latitude, they are significantly stronger in deserts and tundra than forests, and weaker in intensively managed ecosystems. The ubiquitous effects of plant individuals and species on local soil properties imply that individual plant effects have a role in plant–soil feedbacks, linking individual plants with biogeochemical processes at the ecosystem scale.

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Ground vegetation as an indicator of ecological integrity

Environmental Reviews ◽

10.1139/a09-012 ◽

2009 ◽

Vol 17 (NA) ◽

pp. 249-265 ◽

Cited By ~ 10

Author(s):

Richard LaPaix ◽

Bill Freedman ◽

David Patriquin

Keyword(s):

Plant Species ◽

Ecological Integrity ◽

Diversity Indices ◽

Permanent Plots ◽

Individual Species ◽

Ground Vegetation ◽

Individual Plant ◽

Ecological Processes ◽

Assessment Index ◽

Anthropogenic Stressors

Indicators are being sought for monitoring the ecological integrity of forests and other kinds of ecosystems. Biological measures are commonly used as indicators because of their inherent ecological importance and ability to provide insight into environmental change. Such measures are commonly based on data from sets of permanent plots in which the abundances of plant species are monitored. However, the data may be difficult to interpret, especially if corresponding information on natural and anthropogenic stressors is lacking. In this review, we examine general principles of indicator use and discuss the types of plot-based compositional measures obtained from vegetation that may be most relevant for monitoring ecological integrity. Our focus is on the ground vegetation of forested ecosystems, but the principles discussed are relevant to other vegetation types. Individual plant species, guilds, aliens, diversity indices, Ellenberg indicator values, the floristic quality assessment index, multivariate and multimetric indicators are examined, as well as concepts of threshold changes and the need for reference states. The usefulness of any given approach tends to be highly context specific. In particular, the value of using individual species as indicators is highly dependant on factors such as the character of the floristic community of interest and the types and intensities of anthropogenic stressors. Alien species are considered to be especially valuable indicators of changes in ecological integrity due to their established relationships with anthropogenic stressors, known historical state, relevance to all floristic communities, and ability to cause undesirable changes to biodiversity and ecological processes.

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Ecological success of sexual and asexual reproductive strategies invading an environmentally unstable habitat

10.1101/2020.02.10.942466 ◽

2020 ◽

Author(s):

Willian T.A.F. Silva ◽

Anna Nyqvist ◽

Per R. Jonsson ◽

Karin C. Harding

Keyword(s):

Environmental Stress ◽

Asexual Reproduction ◽

Reproductive Strategies ◽

Allee Effect ◽

Quantitative Approach ◽

Ecological Processes ◽

The Core ◽

Core Habitat ◽

Geographic Parthenogenesis ◽

Sexual And Asexual Reproduction

AbstractMany aspects of sexual and asexual reproduction have been studied empirically and theoretically. The differences between sexual and asexual reproduction within a species often lead to a biased geographical distribution of individuals with different reproductive strategies. While sexuals are more abundant in the core habitat, asexuals are often found in marginal habitats along the edge of the species distribution. This pattern, called geographic parthenogenesis, has been observed in many species but the mechanisms reponsible for generating it are poorly known. We used a quantitative approach using a metapopulation model to explore the ecological processes that can lead to geographic parthenogenesis and the invasion of new habitats by different reproductive strategies. We analyzed the Allee effect on sexual populations and the population sensitivity to environmental stress during the invasion of a marginal, unstable habitat to demonstrate that a complex interaction between the Allee effect, sensitivity to environmental stress and the environmental conditions can determine the relative success of competing reproductive strategies during the initial invasion and longterm establishment in the marginal habitat. We discuss our results in the light of previous empirical and theoretical studies.Author SummaryIndividuals can reproduce with or without sex. Very often, closely related species are distributed in a such a way that the sexually reproducing species is most frequently found in the core habitat while the asexually reproducing species is found on the edge of the habitat range. This biased distribution of reproductive strategies across a habitat range is called geographic parthenogenesis and has been observed in several species. While many processes have been proposed to explain such a pattern, a quantitative approach of the ecological processes was absent. We investigated important differences between sexual and asexual reproduction and how these differences affect the success of sexuals and asexuals invading a marginal, unstable environment. We showed that the relative frequency of each reproductive strategy in the marginal habitat depends on how much sexuals rely on population density to reproduce and how much asexuals are affected by environmental stress relative to sexuals. Our study presents a quantitative ecological explanation for geographic parthenogenesis and provides the conditions under which different distribution patterns can emerge.

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Glutathione (GSH) Production as Protective Adaptation Against Light Regime Radiation of Symbiodinium Natural Population

ILMU KELAUTAN Indonesian Journal of Marine Sciences ◽

10.14710/ik.ijms.22.3.121-125 ◽

2017 ◽

Vol 22 (3) ◽

pp. 121 ◽

Cited By ~ 1

Author(s):

Moh Muhaemin ◽

Dedi Soedharma ◽

Hawis H Madduppa ◽

Neviaty Putri Zamani

Keyword(s):

Molecular Weight ◽

Environmental Stress ◽

Adaptive Response ◽

Productivity Loss ◽

Initial Response ◽

Light Regime ◽

Uv Exposure ◽

Low Molecular Weight ◽

Specific Adaptation ◽

Wide Range

Glutathione (GSH), as a wide range of low molecular weight, which found in marine microalgae and event bacteria, are essential to prevent photooxidation and productivity loss from these Radical Oxigen Species (ROS). Symbiodinium, endo-symbiont of corals, were exposed with different UV radiation combined with irradiance treatments to explore biomass specific initial response. Intracellular glutahione was observed as potential adaptive response of Symbiodinium population under environmental specific stress. The result showed that GSH production increased significantly with increasing irradiance and/or UV levels. GSH concentration was fluctuated among populations exposed by different irradiance treatments, but not effected by UV and irradiance exposure. GSH production as a response of UV exposure was higher than irradiance treatments. Both these high correlative fluctuation of intracellular GSH production and the presence of both treatments indicated protective specific adaptation of Symbiodinium under specific environmental stress, respectively. Keywords: zooxanthellae, irradiance, glutathione (GSH), corals, Fungia

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Change in zooxanthellae and mucocyte tissue density as an adaptive response to environmental stress by the coral, Montastraea annularis

Marine Biology ◽

10.1007/s00227-009-1267-1 ◽

2009 ◽

Vol 156 (11) ◽

pp. 2379-2389 ◽

Cited By ~ 24

Author(s):

Alan M. Piggot ◽

Bruce W. Fouke ◽

Mayandi Sivaguru ◽

Robert A. Sanford ◽

H. Rex Gaskins

Keyword(s):

Environmental Stress ◽

Adaptive Response ◽

Tissue Density ◽

Montastraea Annularis

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Community level individual-based plant-pollinator networks unveil pollen flow dynamics and plant reproductive success

10.1101/2021.04.23.441120 ◽

2021 ◽

Author(s):

Alfonso Allen-Perkins ◽

María Hurtado ◽

David García-Callejas ◽

Oscar Godoy ◽

Ignasi Bartomeus

Keyword(s):

Reproductive Success ◽

Plant Species ◽

Individual Plant ◽

Ecological Communities ◽

Ecological Processes ◽

Individual Level ◽

Heterospecific Pollen ◽

Plant Reproductive Success ◽

The Individual ◽

Plant Pollinator

Ecological networks are a widely used tool to understand the dynamics of ecological communities in which plants interact with their pollinator counterparts. However, while most mutualistic networks have been defined at the species level, ecological processes, such as pollination, take place at the individual level. This recognition has led to the development of individual-based networks, yet current approaches only account for individuals of a single plant species due to conceptual and mathematical limitations. Here, we introduce a multilayer framework designed to depict the conspecific and heterospecific pollen flows mediated by floral visitors among plant individuals belonging to different species. Pollen transfer is modeled as a transport-like system, where an ensemble of conspecific plant-pollinator “circuits” are coupled through pollinators. With this physical conceptualization of ecological processes, we investigate how the reproductive success of plant individuals is affected by the overall dynamics of the whole multilayer network (macrostructure), as well as by their local position within the network (mesostructure). To illustrate this multiscale analysis, we apply it to a dataset of nine well-resolved individual plant-pollinator interaction networks from annual plant grasslands. Our results show that the resulting individual-based networks are highly modular, with insect visitors effectively connecting individuals of the same and different plant species. We also obtain empirical evidence that network structure is critical for modulating individual plant reproduction. In particular, the mesoscale level is the best descriptor of plant reproductive success, as it integrates the net effect of local heterospecific and conspecific interactions on seed production of a given individual. We provide a simple, but robust set of metrics to scale down network ecology to functioning properties at the individual level, where most ecological processes take place, hence moving forward the description and interpretation of multitrophic communities across scales.

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Treating Velopharyngeal Inadequacy Using Bilateral Buccal Flap Revision Palatoplasty

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2019_pers-sig5-2019-0005 ◽

2019 ◽

Vol 4 (5) ◽

pp. 878-892

Author(s):

Joseph A. Napoli ◽

Linda D. Vallino

Keyword(s):

Systematic Review ◽

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Cleft Lip ◽

Cleft Lip And Palate ◽

A Priori ◽

Sufficient Evidence ◽

Obstructive Sleep ◽

Before And After ◽

Buccal Flap

Purpose The 2 most commonly used operations to treat velopharyngeal inadequacy (VPI) are superiorly based pharyngeal flap and sphincter pharyngoplasty, both of which may result in hyponasal speech and airway obstruction. The purpose of this article is to (a) describe the bilateral buccal flap revision palatoplasty (BBFRP) as an alternative technique to manage VPI while minimizing these risks and (b) conduct a systematic review of the evidence of BBFRP on speech and other clinical outcomes. A report comparing the speech of a child with hypernasality before and after BBFRP is presented. Method A review of databases was conducted for studies of buccal flaps to treat VPI. Using the principles of a systematic review, the articles were read, and data were abstracted for study characteristics that were developed a priori. With respect to the case report, speech and instrumental data from a child with repaired cleft lip and palate and hypernasal speech were collected and analyzed before and after surgery. Results Eight articles were included in the analysis. The results were positive, and the evidence is in favor of BBFRP in improving velopharyngeal function, while minimizing the risk of hyponasal speech and obstructive sleep apnea. Before surgery, the child's speech was characterized by moderate hypernasality, and after surgery, it was judged to be within normal limits. Conclusion Based on clinical experience and results from the systematic review, there is sufficient evidence that the buccal flap is effective in improving resonance and minimizing obstructive sleep apnea. We recommend BBFRP as another approach in selected patients to manage VPI. Supplemental Material https://doi.org/10.23641/asha.9919352

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