Auswahl der wissenschaftlichen Literatur zum Thema „Anthropogenic signal“
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Zeitschriftenartikel zum Thema "Anthropogenic signal"
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Gordeev, Vasily, Sergey Malyshkov und Vitaly Polivach. „GEOPHYSICAL MONITORING OF TECHNOGENIC HAZARDS ON ANTHROPOGENIC SOILS“. Interexpo GEO-Siberia 1, Nr. 2 (2019): 65–72. http://dx.doi.org/10.33764/2618-981x-2019-1-2-65-72.
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Rock stability estimation tasks on anthropogenic soils require both preliminary survey and on-going real-time monitoring providing alerts on possible cave-in threats. Using VLF monitoring data incorporated into software-hardware geodynamical processes automated surveillance system allows to accomplish that task. Authors describe a unique method, based on Earth’s natural pulsed electro-magnetic field (ENPEMF) recording and make conclusions on the efficiency of the solutions ap-plied for hazardous geodynamic processes monitoring on anthropogenic soils. The principle of the method is to distinguish spatial variations of ENPEMF signal against diurnal oscillations and tech-nogenic signals. Correlation between relative signal intensity and stress-strained state of the rocks is experimentally demonstrated.
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Zhang, Honghai, und Thomas L. Delworth. „Detectability of Decadal Anthropogenic Hydroclimate Changes over North America“. Journal of Climate 31, Nr. 7 (April 2018): 2579–97. http://dx.doi.org/10.1175/jcli-d-17-0366.1.
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Regional hydroclimate changes on decadal time scales contain substantial natural variability. This presents a challenge for the detection of anthropogenically forced hydroclimate changes on these spatiotemporal scales because the signal of anthropogenic changes is modest, compared to the noise of natural variability. However, previous studies have shown that this signal-to-noise ratio can be greatly improved in a large model ensemble where each member contains the same signal but different noise. Here, using multiple state-of-the-art large ensembles from two climate models, the authors quantitatively assess the detectability of anthropogenically caused decadal shifts in precipitation-minus-evaporation (PmE) mean state against natural variability, focusing on North America during 2000–50. Anthropogenic forcing is projected to cause detectable (signal larger than noise) shifts in PmE mean state relative to the 1950–99 climatology over 50%–70% of North America by 2050. The earliest detectable signals include, during November–April, a moistening over northeastern North America and a drying over southwestern North America and, during May–October, a drying over central North America. Different processes are responsible for these signals. Changes in submonthly transient eddy moisture fluxes account for the northeastern moistening and central drying, while monthly atmospheric circulation changes explain the southwestern drying. These model findings suggest that despite the dominant role of natural internal variability on decadal time scales, anthropogenic shifts in PmE mean state can be detected over most of North America before the middle of the current century.
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Svoma, Bohumil M., und Robert C. Balling. „An anthropogenic signal in Phoenix, Arizona winter precipitation“. Theoretical and Applied Climatology 98, Nr. 3-4 (24.02.2009): 315–21. http://dx.doi.org/10.1007/s00704-009-0121-1.
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Akçay, Çağlar, und Michael D. Beecher. „Multi-modal communication: song sparrows increase signal redundancy in noise“. Biology Letters 15, Nr. 10 (Oktober 2019): 20190513. http://dx.doi.org/10.1098/rsbl.2019.0513.
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Although the effects of anthropogenic noise on animal communication have been studied widely, most research on the effect of noise in communication has focused on signals in a single modality. Consequently, how multi-modal communication is affected by anthropogenic noise is relatively poorly understood. Here, we ask whether song sparrows ( Melospiza melodia ) show evidence of plasticity in response to noise in two aggressive signals in acoustic and visual modalities. We test two hypotheses: (i) that song sparrows will shift signalling effort to the visual modality (the multi-modal shift hypothesis) and (ii) that they will increase redundancy of their multi-modal signalling (the back-up signal hypothesis). We presented male song sparrows with song playback and a taxidermic mount with or without a low-frequency acoustic noise from a nearby speaker. We found that males did not switch their signalling effort to visual modality (i.e. wing waves) in response to the noise. However, the correlation between warbled soft songs and wing waves increased in the noise treatment, i.e. signals became more redundant. These results suggest that when faced with anthropogenic noise, song sparrows can increase the redundancy of their multi-modal signals, which may aid in the robustness of the communication system.
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Hedegaard, G. B., J. H. Christensen und J. Brandt. „The relative importance of impacts from climate change vs. emissions change on air pollution levels in the 21st century“. Atmospheric Chemistry and Physics Discussions 12, Nr. 9 (19.09.2012): 24501–30. http://dx.doi.org/10.5194/acpd-12-24501-2012.
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Abstract. So far several studies have analysed the impacts of climate change on future air pollution levels. Significant changes due to impacts of climate change have been made clear. Nevertheless, these changes are not yet included in national, regional or global air pollution reduction strategies. The changes in future air pollution levels are caused by both impacts from climate change and anthropogenic emission changes and the importance of these signals needs to be quantified and compared. In this study we use the Danish Eulerian Hemispheric Model (DEHM) driven on meteorological input data from the coupled Atmosphere-Ocean General Circulation Model ECHAM5/MPI-OM and forced with the newly developed RCP4.5 emissions. The relative importance of the climate signal and the signal from changes in anthropogenic emissions on the future ozone, black carbon (BC), total particulate matter with a diameter below 2.5 μm (total PM2.5 including BC, primary organic carbon (OC), mineral dust and secondary inorganic aerosols (SIA)) and total nitrogen (including NHx + NOy) has been determined. For ozone the impacts of anthropogenic emissions dominates though a climate penalty is found in the Arctic region and the Northwestern Europe where the signal from climate change dampens the effect from the projected emission reductions of anthropogenic ozone precursors. The investigated particles are even more dominated by the impacts from emission changes. For black carbon the emission signal dominates slightly at high latitudes increasing to be up to an order of magnitude larger close to the emission sources in temperate and subtropical areas. Including all particulate matter with a diameter below 2.5 μm (total PM2.5) enhances the dominance from emissions change. In contrast, total nitrogen (NHx + NOy) in parts of the Arctic and at low latitudes is dominated by impacts of climate change.
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Lombardozzi, Danica, Gordon B. Bonan und Douglas W. Nychka. „The emerging anthropogenic signal in land–atmosphere carbon-cycle coupling“. Nature Climate Change 4, Nr. 9 (27.07.2014): 796–800. http://dx.doi.org/10.1038/nclimate2323.
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Francis, Clinton D., Catherine P. Ortega und Alexander Cruz. „Different behavioural responses to anthropogenic noise by two closely related passerine birds“. Biology Letters 7, Nr. 6 (25.05.2011): 850–52. http://dx.doi.org/10.1098/rsbl.2011.0359.
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Anthropogenic noise, now common to many landscapes, can impair acoustic communication for many species, yet some birds compensate for masking by noise by altering their songs. The phylogenetic distribution of these noise-dependent signal adjustments is uncertain, and it is not known whether closely related species respond similarly to noise. Here, we investigated the influence of noise on habitat occupancy rates and vocal frequency in two congeneric vireos with similar song features. Noise exposure did not influence occupancy rates for either species, yet song features of both changed, albeit in different ways. With increases in noise levels, plumbeous vireos ( Vireo plumbeus ) sang shorter songs with higher minimum frequencies. By contrast, grey vireos ( Vireo vicinior ) sang longer songs with higher maximum frequencies. These findings support the notion that vocal plasticity may help some species occupy noisy areas, but because there were no commonalities among the signal changes exhibited by these closely related birds, it may be difficult to predict how diverse species may modify their signals in an increasingly noisy world.
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Seong, Min-Gyu, Seung-Ki Min, Yeon-Hee Kim, Xuebin Zhang und Ying Sun. „Anthropogenic Greenhouse Gas and Aerosol Contributions to Extreme Temperature Changes during 1951–2015“. Journal of Climate 34, Nr. 3 (Februar 2021): 857–70. http://dx.doi.org/10.1175/jcli-d-19-1023.1.
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AbstractThis study conducted a detection and attribution analysis of the observed global and regional changes in extreme temperatures during 1951–2015. HadEX3 observations were compared with multimodel simulations from the Coupled Model Intercomparison Project phase 6 (CMIP6) using an optimal fingerprinting technique. Annual maximum daily maximum and minimum temperatures (TXx and TNx; warm extremes) and annual minimum daily maximum and minimum temperatures (TXn and TNn; cold extremes) over land were analyzed considering global, continental, and subcontinental scales. Response patterns (fingerprints) of extreme temperatures to anthropogenic (ANT), greenhouse gases (GHG), aerosols (AA), and natural (NAT) forcings were obtained from CMIP6 forced simulations. The internal variability ranges were estimated from preindustrial control simulations. A two-signal detection analysis where the observations are regressed onto ANT and NAT fingerprints simultaneously reveals that ANT signals are robustly detected in separation from NAT over global and all continental domains (North and South America, Europe, Asia, and Oceania) for most of the extreme indices. ANT signals are also detected over many subcontinental regions, particularly for warm extremes (more than 60% of 33 subregions). A three-signal detection analysis that considers GHG, AA, and NAT fingerprints simultaneously demonstrates that GHG signals are detected in isolation from other external forcings over global, continental, and several subcontinental domains especially for warm extremes, explaining most of the observed warming. Moreover, AA influences are detected for warm extremes over Europe and Asia, indicating significant offsetting cooling contributions. Overall, human influences are detected more frequently, compared to previous studies, particularly for cold extremes, due to the extended period and the improved spatial coverage of observations.
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Lillis, Ilse Van, und Olaf Boebel. „Marine soundscape planning: Seeking acoustic niches for anthropogenic sound“. Journal of Ecoacoustics 2, Nr. 1 (29.03.2018): 1. http://dx.doi.org/10.22261/jea.5gsnt8.
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Both marine mammals and hydroacoustic instruments employ underwater sound to communicate, navigate or infer information about the marine environment. Concurrent timing of acoustic activities using similar frequency regimes may result in (potentially mutual) interference of acoustic signals when both sources are within audible range of the recipient. While marine mammal fitness might be negatively impacted upon, both on individual and population level, hydroacoustic studies may generate low quality data or suffer data loss as a result of bioacoustic interference. This article pursues, in analogy to landscape planning, the concept of marine soundscape planning to reconcile potentially competing uses of acoustic space by managing the anthropogenic sound sources. We here present a conceptual framework exploring the potential of soundscape planning in reducing (mutual) acoustic interference between hydroacoustic instrumentation and marine mammals. The basis of this framework is formed by the various mechanisms by which acoustic niche formation (i.e., the partitioning of the acoustic space) occurs in species-rich communities that acoustically coexist while maintaining high fidelity (hi-fi) soundscapes, i.e., by acoustically partitioning the environment on the basis of time, space, frequency and signal structure. Hydroacoustic measurements often exhibit certain flexibility in their timing, and even instrument positioning, potentially offering the opportunity to minimize the ecological imprint of their operation. This study explores how the principle of acoustic niches could contribute to reduce potential (mutual) acoustic interference based on actual acoustic data from three recording locations in polar oceans. By employing marine soundscape planning strategies, entailing shifting the timing or position of hydroacoustic experiments, or adapting signal structure or frequency, we exemplify the potential efficacy of smart planning for four different hydroacoustic instrumentation types: multibeam echosounders, air guns, RAFOS (Ranging and Fixing of Sound) and tomographic sound sources.
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Dunlop, Rebecca, Michael Noad und Dorian Houser. „Using behavioural response experiments to measure humpback whale hearing in noise“. Journal of the Acoustical Society of America 154, Nr. 4_supplement (01.10.2023): A46. http://dx.doi.org/10.1121/10.0022751.
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Currently, there are no direct data on mysticete hearing in noise. Available data comes from anatomical modelling, the assumption they can hear their own sounds, and studies on the effects of various sources of anthropogenic noise on their behavior. This study used a behavioral response study design to quantify humpback whale hearing in natural ocean noise. Tonal signals, ranging from 250 Hz to 16kHz, were used as the stimuli, and a change in humpback group behavior indicated the whales heard the signal. Individual whale and group behavior were quantified using a combination of land-based tracking data of groups and tag data deployed on individual whales to record fine-scale 3D movement underwater. The signal-to-noise ratio was estimated at the initial response position of the group or whale, assuming this was the level at which they first detected the tone in noise. Results confirm that humpback whales responded to signals in noise at detection levels comparable to other marine mammals and that their ability to hear signals in noise at higher frequencies is better than expected. This provides empirical data on hearing in a mysticete which can be used to better predict the acoustic impacts of anthropogenic noise on marine mammals.
Dissertationen zum Thema "Anthropogenic signal"
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Knust, Andrew E. „Uncertainties associated with using an anthropogenic fluctuating signal to estimate hyporheic exchange“. abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1438921.
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Narango, Desiree Lynn. „Causes and Consequences of Urban-associated Song Variation: A Study of Vocal Behavior in the Northern Cardinal (Cardinalis cardinalis)“. The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1337792731.
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Silvy, Yona. „Emergence des changements de température et de salinité dans l’océan intérieur en réponse au changement climatique : échelles de temps et mécanismes“. Electronic Thesis or Diss., Sorbonne université, 2022. http://www.theses.fr/2022SORUS124.
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Le changement climatique d’origine humaine impacte déjà toutes les régions habitées de la planète. 90% de l’excès de chaleur associé aux activités humaines a été absorbé par l’océan depuis les années 1970, atténuant en grande partie le réchauffement atmosphérique, mais impactant fortement les sociétés humaines et la vie marine. Dans cette thèse, j’explore à l’aide d’ensembles de modèles de climat et de simulations numériques dédiées, où et quand les changements de température et de salinité dans l’océan intérieur deviennent assez grands pour être différenciés de la variabilité interne, ainsi que les mécanismes physiques associés. Nous trouvons ainsi que le signal climatique dans les masses d’eau de l’océan supérieur émerge entre la fin du XXème et les premières décennies du XXIème siècle. Les eaux modales des moyennes latitudes de l’hémisphère Sud émergent plus tôt que leurs homologues de l’hémisphère Nord. Le réchauffement associé à ces échelles de temps est principalement du à une absorption de chaleur transportée passivement dans l’océan intérieur. Dans les profondeurs de l’océan, les changements de circulation jouent un rôle plus important aux échelles de temps d’émergence du signal climatique. Le gain de flottabilité en surface dans les régions subpolaires provoque un ralentissement de la circulation méridienne de retournement. Cela réchauffe les eaux intérieures et abyssales de l’Océan Austral dès le milieu du XXème, venant s’ajouter au faible transport passif de chaleur, alors que cela le contre dans les profondeurs de l’Atlantique Nord et retarde l’émergence. Bien que les modèles de climat passent à côté de certains aspects importants de la réponse océanique au changement climatique, ils permettent d’apporter des éléments sur l’équilibre de processus en jeu, et suggèrent que l’influence humaine impacte déjà de grandes parties de l’océanHuman-induced climate change is already affecting every inhabited region of the planet. Yet, over 90% of the excess heat associated with human activities has been absorbed by the ocean since the 1970s, which acts to largely damp atmospheric warming, but has large impacts on human societies and marine life. In this thesis, I explore when and where thermohaline changes in the ocean interior become large enough to be unambiguously set apart from internal variability and investigate their associated physical drivers, using ensembles of climate models and dedicated numerical experiments. We find that the climate signal in the upper ocean water-masses emerges between the late 20th century and the first decades of the 21st. The Southern Hemisphere mid-latitude Mode Waters emerge before their Northern Hemisphere counterparts. The associated warming at these timescales is mostly caused by the uptake of heat from the atmosphere, passively transported into the ocean interior. In the deeper parts of the ocean, circulation changes play a more important role in the emergence timescales of the climate signals. Increased buoyancy gain at the surface in the subpolar areas cause a slowdown in the meridional overturning circulation. This warms the subsurface and abyssal waters in the Southern Ocean as soon as the mid-20th century, adding up to the weaker passive uptake of heat, but counteracts it in the deep North Atlantic over the 21st, delaying the emergence. Although climate models miss some important aspects of the ocean response to climate change, they allow to shed light on the balance of processes at play, and suggest anthropogenic influence has already spread to large parts of the ocean
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Sexton, David M. H. „Estimation of anthropogenic signals in an atmospheric climate model, using the General Linear Model“. Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342120.
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Galindo, Romero Marta. „Spatial Variations in the Acoustic Peak Pressure of Impulsive Low Frequency Anthropogenic Signals in Underwater Marine Environments“. Thesis, Curtin University, 2017. http://hdl.handle.net/20.500.11937/59661.
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A method to predict spatial variations in the peak pressure level of impulsive low frequency anthropogenic signal propagating in marine environments is presented. The method is based on the correlation between the peak pressure level and the sound exposure level, and the application of extreme value theory to estimate fluctuations of the peak pressure around its mean value in varying ocean environments. The method was examined using signals from offshore seismic surveys and pile driving.
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Rasmussen, Cecily Ellen. „Anthropogenic disturbance of environmental signals retained in massive corals“. Thesis, 1994. https://researchonline.jcu.edu.au/33138/1/33138-rasmussen-1994-volume1.pdf.
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Samples of Porites coral were removed from seven different reefs (No Name, Hastings, Upolu, Thetford, Batt, Green Island and Brook Islands Reefs), including two from the same reef (Green Island Reef), within Australia's Great Barrier Reef Marine Park. Chemical and morphological data retrieved from these samples were used to investigate historical change in water quality surrounding the growing corals, particularly as this related to the increased use of phosphatic fertiliser on the nearby mainland. The study focused on a narrow section of the continental shelf adjacent to the mouth of the Barron River. In this area coral reefs are close to a mainland significantly altered for anthropogenic purposes. No Name Reef (approximately 300 km north of the study area and reasonably distant from known anthropogenic input) was included as a control. The Brook Islands Reef (approximately 300 km south of the study area) was added for geographic variability. Support data was gained by a two year nutrient monitoring programme of the Barron and Mossman River catchments, and marine waters adjacent to these two river systems. Additional information was acquired by the experimental supplementation of Acropora formosa corals with 2.0 μM, 4.0 μM and 8.0 μM PO₄.
Stream phosphate levels responded rapidly to rainfall. During the April 1989 flood period between 710 and 2,850 tonnes of Superphosphate were delivered into the ocean. Estimates vary according to the presumed ratio of soluble to particulate phosphate in the flood plume (e.g. see Cosser 1987 and Brodie & Mitchell 1992). The lower figure is nearly half the total industry estimated fertiliser usage (1810 tonnes) for the Far Northern Statistical Division during 1988. The greater figure is more than a third higher than Australian Bureau of Statistics figures for the same period (Pulsford 1990). The marine monitoring program suggested that nutrient monitoring was an insufficient method of estimating water quality.
The phosphate supplementation experiment showed that elevated levels of phosphate hindered calcium carbonate production with considerable alteration to the internal and external morphology of the coral skeleton.
Chemical analysis of the Porites samples suggested that intra-reefal variation in the coral skeleton was minor, but with sufficient inconsistencies in the annual record to suggest that localised, micro-environmental conditions exist and should be recognised when attempting to reconstruct environmental records from the coral skeleton. Statistically, the inner- and inner/mid-shelf sample sets were significantly different from each other and from all other sample sets. No significant statistical difference could be distinguished in the mid- to outer-shelf sample sets, but the relative contribution of each element differed for each of these sample sets.
The difference between the samples from nearer to shore and those from the outershelf was also apparent in the reconstructed coral inferred environmental record. Strontium-based sea-surface temperature estimates provided an adequate record of historical sea surface temperatures from the mid- to outer-shelf samples (No Name, Hastings, Upolu and Thetford Reefs), but were unreliable for the closer to shore samples (Batt, Green Island and Brook Island Reefs).
Similar inconsistencies were noted in associations with climatic variables. Data from the outer-shelf No Name Reef sample correlated with climatic data associated with the Southern Oscillation Index (SOI) while data from the Green Island Reef sample correlated with Mean Sea Level Pressure read at Darwin. These inconsistencies were inherent in the coral-inferred record and were not associated with anthropogenic influence.
However, ambiguities in the chemical composition and morphological structure of the Green Island sample were noted post-1950. These inconsistencies were statistically correlated to the use of fertiliser on the nearby mainland. Changes to the internal porosity of the coral skeleton were similar to those noted in the experimental phosphate supplementation programme.
The study concludes that chemical and morphological variations in the skeleton of the massive Porites coral are suitable for hindcasting paleoenvironmental conditions laid down in the skeleton at the time of precipitation. The study further concludes that there is significant evidence of anthropogenic influence in the Green Island sample, and that this influence is related to the use of fertilisers on the nearby mainland.
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Bent, Adam M. „Consequences of anthropogenic noise when conflicting with sexually selected acoustic signals“. Thesis, 2019. https://arro.anglia.ac.uk/id/eprint/704519/1/Bent_2019.pdf.
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The signalling systems of species throughout the Animal Kingdom are at risk of disruption from human disturbances. Anthropogenic noise is a prominent acoustic pollutant in many environments and is known to conflict with the acoustic sexual signalling systems of both terrestrial and aquatic animals. However, the consequences and causes of such a conflict largely remain unknown, especially in invertebrate species. The experiments I present in this thesis highlight the behavioural and physiological consequences of anthropogenic noise when conflicting with an insect’s acoustic signals. Additionally, I also consider the acoustic characteristics necessary in any given stimulus to cause such a disruption. To measure these consequences, I observed the sexual signalling systems of the Mediterranean field cricket, Gryllus bimaculatus, under conditions of anthropogenic noise and conducted behavioural, acoustic, and physiological analyses. I found the acoustic signal used to detect the location of a signalling individual (the ‘calling song’) suffered reduced reception under anthropogenic noise conditions, shown by a reduction in female responses. Additionally, I also found the acoustic signal used during courtship displays (the ‘courtship song’) sustained reduced signal transmission, as males signalled less, and reduced signal perception, as females failed to distinguish between high and low ‘quality’ songs. However, aggressive encounters between two males, which feature an acoustic signal (the ‘aggressive song’), remained stable under similar acoustic conditions. Physiological analyses revealed potential energetic costs related to acoustic signals that had been altered to combat disruption from anthropogenic noise. Furthermore, the differences I observed between noise conditions highlighted the acoustic characteristic that are important in causing this disruption. The results I present in this thesis detail the deleterious consequences of anthropogenic noise disrupting invertebrate sexual signalling systems, both in terms of behaviour and energetic costs. Additionally, I discuss the variability in signals that may be disrupted by anthropogenic noise conditions and the acoustic characteristics that drive this disruption in the first place. This further cements anthropogenic disturbances as a new and dangerous selection pressure facing many animal populations.
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D'anjou, Robert M. „Holocene Climate and Environmental Changes: Disentangling Natural and Anthropogenic Signals in the Sedimentary Record of Lake Lilandsvatnet (nw Norway)“. 2012. https://scholarworks.umass.edu/theses/854.
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This thesis presents a multi-proxy paleoenvironmental reconstruction from the sedimentary archives of Lilandsvatnet, a small arctic lake on Vestvågøy, in the Lofoten Islands, Norway. Lofoten has a rich history of human settlements existing throughout the Holocene. The catchment of Lilandsvatnet was the location of a prominent Viking chieftain farm that existed throughout the Iron Age, and the sedimentary archive contains a strong signal of prehistoric and historic human settlements and land-use practices. Paleoenvironmental reconstructions in this thesis show evidence for Holocene environmental variability in response to both natural and anthropogenic forcing. Cryptotephra deposits from Icelandic eruptions further contrain sediment chronology in the study, allowing reconstructions of subtle changes in the landscape with excellent chronological control during the late Holocene period of settlement. Additionally, I attempt to improve existing methods for crypto-tephrochronology through the development of new techniques.
Bücher zum Thema "Anthropogenic signal"
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Fredericks, Sarah E. Environmental Guilt and Shame. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198842699.001.0001.
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Bloggers confessing that they waste food, nongovernmental organizations naming corporations selling unsustainably harvested seafood, and veterans apologizing to Native Americans at the Standing Rock Sioux Reservation for environmental and social devastation caused by the United States government all signal the existence of action-oriented guilt and identity-oriented shame about participation in environmental degradation. Environmental Guilt and Shame demonstrates that these moral emotions are common among environmentally friendly segments of the United States but have received little attention from environmental ethicists though they can catalyze or hinder environmental action. Concern about environmental guilt and shame among “everyday environmentalists” reveals the practical, emotional, ethical, and existential issues raised by environmental guilt and shame and ethical insights about guilt, shame, responsibility, agency, and identity. A typology of guilt and shame enables the development and evaluation of these ethical insights. Environmental Guilt and Shame makes three major claims: First, individuals and collectives, including the diffuse collectives that cause climate change, can have identity, agency, and responsibility and thus guilt and shame. Second, some agents, including collectives, should feel guilt and/or shame for environmental degradation if they hold environmental values and think that their actions shape and reveal their identity. Third, a number of conditions are required to conceptually, existentially, and practically deal with guilt and shame’s effects on agents. These conditions can be developed and maintained through rituals. Existing rituals need more development to fully deal with individual and collective guilt and shame as well as the anthropogenic environmental degradation that may spark them.
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Brönmark, Christer, und Lars-Anders Hansson. Biodiversity and Environmental Threats. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198713593.003.0006.
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The last chapter of Lakes and Ponds deals with how human activities affect the natural ecosystems and their function through eutrophication, contamination, acidification, brownification and increases in UV radiation, and how such anthropogenic disturbances may affect biodiversity and the ability of organisms to utilize a specific habitat. In addition, the chapter addresses novel environmental threats, such as global climate change and effects from our everyday chemicals, such as contraceptives, nanoparticles and antidepressant drugs. However, also possibilities and signs of improvement are discussed, providing hope for coming generations.
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Jue, Melody, und Rafico Ruiz, Hrsg. Saturation. Duke University Press, 2021. http://dx.doi.org/10.1215/9781478013044.
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Bringing together media studies and environmental humanities, the contributors to Saturation develop saturation as a heuristic to analyze phenomena in which the elements involved are difficult or impossible to separate. In ordinary language, saturation describes the condition of being thoroughly soaked, while in chemistry it is the threshold at which something can be maximally dissolved or absorbed in a solution. Contributors to this collection expand notions of saturation beyond water to consider saturation in sound, infrastructure, media, Big Data, capitalism, and visual culture. Essays include analyses of the thresholds of HIV detectability in bloodwork, militarism's saturation of oceans, and the deleterious effects of the saturation of cellphone and wi-fi signals into the human body. By channeling saturation to explore the relationship between media, the environment, technology, capital, and the legacies of settler colonialism, Saturation illuminates how elements, the natural world, and anthropogenic infrastructures, politics, and processes exist in and through each other. Contributors. Marija Cetinić, Jeff Diamanti, Bishnupriya Ghosh, Lisa Yin Han, Stefan Helmreich, Mél Hogan, Melody Jue, Rahul Mukherjee, Max Ritts, Rafico Ruiz, Bhaskar Sarkar, John Shiga, Avery Slater, Janet Walker, Joanna Zylinska
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Christensen, Ole Bøssing, und Erik Kjellström. Projections for Temperature, Precipitation, Wind, and Snow in the Baltic Sea Region until 2100. Oxford University Press, 2018. http://dx.doi.org/10.1093/acrefore/9780190228620.013.695.
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The ecosystems and the societies of the Baltic Sea region are quite sensitive to fluctuations in climate, and therefore it is expected that anthropogenic climate change will affect the region considerably. With numerical climate models, a large amount of projections of meteorological variables affected by anthropogenic climate change have been performed in the Baltic Sea region for periods reaching the end of this century.Existing global and regional climate model studies suggest that:• The future Baltic climate will get warmer, mostly so in winter. Changes increase with time or increasing emissions of greenhouse gases. There is a large spread between different models, but they all project warming. In the northern part of the region, temperature change will be higher than the global average warming.• Daily minimum temperatures will increase more than average temperature, particularly in winter.• Future average precipitation amounts will be larger than today. The relative increase is largest in winter. In summer, increases in the far north and decreases in the south are seen in most simulations. In the intermediate region, the sign of change is uncertain.• Precipitation extremes are expected to increase, though with a higher degree of uncertainty in magnitude compared to projected changes in temperature extremes.• Future changes in wind speed are highly dependent on changes in the large-scale circulation simulated by global climate models (GCMs). The results do not all agree, and it is not possible to assess whether there will be a general increase or decrease in wind speed in the future.• Only very small high-altitude mountain areas in a few simulations are projected to experience a reduction in winter snow amount of less than 50%. The southern half of the Baltic Sea region is projected to experience significant reductions in snow amount, with median reductions of around 75%.
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Szewczyk, Janusz. Rola zaburzeń w kształtowaniu struktury i dynamiki naturalnych lasów bukowo-jodłowo-świerkowych w Karpatach Zachodnich. Publishing House of the University of Agriculture in Krakow, 2018. http://dx.doi.org/10.15576/978-83-66602-35-9.
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The aim of the study was to determine the influence of different disturbances (both natural and anthropogenic) on species composition and stand structure of old-growth mixed mountain forests in the Western Carpathians. These stands are usually dominated by beech, fir and spruce, mixed in different proportions. The tree main species represent different growth strategies, and they compete against each other. The longevity of trees makes the factors influencing the stand structure difficult to identify, even during longitudinal studies conducted on permanent research plots. That is why dendroecological techniques, based upon the annual variability of tree rings, are commonly used to analyze the disturbance histories of old-growth stands. Dendroecological methods make it possible to reconstruct the stand history over several centuries in the past by analyzing the frequency, intensity, duration and spatial scale of disturbances causing the death of trees. Combining the dendroecological techniques with the detailed measurements of stand structure, snag volume, CWD volume, and the analyses of regeneration species composition and structure allows us to identify the factors responsible for the changes in dynamics of mixed mountain forests. Various disturbance agents affect some species selectively, while some disturbances promote the establishment of tree seedlings of specific species by modifying environmental conditions. Describing the disturbance regime requires a broad scope of data on stand structure, on dead wood and tree regeneration, while various factors affecting all the stages of tree growth should be taken into consideration. On the basis of the already published data from permanent sample plots, combined with the available disturbance history analyses from the Western Carpathians, three research hypotheses were formulated. 1. The species composition of mixed mountain forests has been changing for at least several decades. These directional changes are the consequence of simultaneous conifer species decline and expansion of beech. 2. The observed changes in species composition of mixed mountain forests are the effect of indirect anthropogenic influences, significantly changing tree growth conditions also in the forests that are usually considered natural or near-natural. Cumulative impact of these indirect influences leads to the decrease of fir share in the tree layer (spruce decline has also been observed recently),and it limits the representation of this species among seedlings and saplings. The final effect is the decrease of fir and spruce share in the forest stands. 3. Small disturbances, killing single trees or small groups of trees, and infrequent disturbances of medium size and intensity dominate the disturbance regime in mixed mountain forests. The present structure of beech-fir-spruce forests is shaped both by complex disturbance regime and indirect anthropogenic influences. The data were gathered in permanent sample plots in strictly protected areas of Babia Góra, Gorce, and Tatra National Parks, situated in the Western Carpathians. All plots were located in the old-growth forest stands representing Carpathian beech forest community. The results of the measurements of trees, snags, coarse woody debris (CWD) and tree regeneration were used for detailed description of changes in the species composition and structure of tree stands. Tree ring widths derived from increment cores were used to reconstruct the historical changes in tree growth trends of all main tree species, as well as the stand disturbance history within the past two to three hundred years. The analyses revealed complex disturbance history in all of the three forest stands. Intermediate disturbances of variable intensity occurred, frequently separated by the periods of low tree mortality lasting from several decades up to over one hundred years. The intervals between the disturbances were significantly shorter than the expected length of forest developmental cycle, in commonly used theories describing the dynamics of old-growth stands. During intermediate disturbances up to several dozen percent of canopy trees were killed. There were no signs of stand-replacing disturbances, killing all or nearly all of canopy trees. The periods of intense tree mortality were followed by subsequent periods of increased sapling recruitment. Variability in disturbance intensity is one of the mechanisms promoting the coexistence of beech and conifer species in mixed forests. The recruitment of conifer saplings depended on the presence of larger gaps, resulting from intermediate disturbances, while beech was more successful in the periods of low mortality. However, in the last few decades, beech seems to benefit from the period of intense fir mortality. This change results from the influence of long-term anthropogenic disturbances, affecting natural mechanisms that maintain the coexistence of different tree species and change natural disturbance regimes. Indirect anthropogenic influence on tree growth was clearly visible in the gradual decrease of fir increments in the twentieth century, resulting from the high level of air pollution in Europe. Synchronous decreases of fir tree rings’ widths were observed in all three of the sample plots, but the final outcomes depended on the fir age. In most cases, the damage to the foliage limited the competitive abilities of fir, but it did not cause a widespread increase in tree mortality, except for the oldest firs in the BGNP (Babia Góra National Park) plot. BGNP is located in the proximity of industrial agglomeration of Upper Silesia, and it could be exposed to higher level of air pollution than the other two plots. High level of fir regeneration browsing due to the deer overabundance and insufficient number of predators is the second clear indication of the indirect anthropogenic influence on mixed mountain forests. Game impact on fir regeneration is the most pronounced in Babia Góra forests, where fir was almost completely eliminated from the saplings. Deer browsing seems to be the main factor responsible for limiting the number of fir saplings and young fir trees, while the representation of fir among seedlings is high. The experiments conducted in fenced plots located in the mixed forests in BGNP proved that fir and sycamore were the most preferred by deer species among seedlings and saplings. In GNP (Gorce National Park) and TNP (Tatra National Park), the changes in species composition of tree regeneration are similar, but single firs or even small groups of firs are present among saplings. It seems that all of the analysed mixed beech-fir-spruce forests undergo directional changes, causing a systematic decrease in fir representation, and the expansion of beech. This tendency results from the indirect anthropogenic impact, past and present. Fir regeneration decline, alongside with the high level of spruce trees’ mortality in recent years, may lead to a significant decrease in conifers representation in the near future, and to the expansion of beech forests at the cost of mixed ones.
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Xue, Yongkang, Yaoming Ma und Qian Li. Land–Climate Interaction Over the Tibetan Plateau. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228620.013.592.
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The Tibetan Plateau (TP) is the largest and highest plateau on Earth. Due to its elevation, it receives much more downward shortwave radiation than other areas, which results in very strong diurnal and seasonal changes of the surface energy components and other meteorological variables, such as surface temperature and the convective atmospheric boundary layer. With such unique land process conditions on a distinct geomorphic unit, the TP has been identified as having the strongest land/atmosphere interactions in the mid-latitudes.Three major TP land/atmosphere interaction issues are presented in this article: (1) Scientists have long been aware of the role of the TP in atmospheric circulation. The view that the TP’s thermal and dynamic forcing drives the Asian monsoon has been prevalent in the literature for decades. In addition to the TP’s topographic effect, diagnostic and modeling studies have shown that the TP provides a huge, elevated heat source to the middle troposphere, and that the sensible heat pump plays a major role in the regional climate and in the formation of the Asian monsoon. Recent modeling studies, however, suggest that the south and west slopes of the Himalayas produce a strong monsoon by insulating warm and moist tropical air from the cold and dry extratropics, so the TP heat source cannot be considered as a factor for driving the Indian monsoon. The climate models’ shortcomings have been speculated to cause the discrepancies/controversies in the modeling results in this aspect. (2) The TP snow cover and Asian monsoon relationship is considered as another hot topic in TP land/atmosphere interaction studies and was proposed as early as 1884. Using ground measurements and remote sensing data available since the 1970s, a number of studies have confirmed the empirical relationship between TP snow cover and the Asian monsoon, albeit sometimes with different signs. Sensitivity studies using numerical modeling have also demonstrated the effects of snow on the monsoon but were normally tested with specified extreme snow cover conditions. There are also controversies regarding the possible mechanisms through which snow affects the monsoon. Currently, snow is no longer a factor in the statistic prediction model for the Indian monsoon prediction in the Indian Meteorological Department. These controversial issues indicate the necessity of having measurements that are more comprehensive over the TP to better understand the nature of the TP land/atmosphere interactions and evaluate the model-produced results. (3) The TP is one of the major areas in China greatly affected by land degradation due to both natural processes and anthropogenic activities. Preliminary modeling studies have been conducted to assess its possible impact on climate and regional hydrology. Assessments using global and regional models with more realistic TP land degradation data are imperative.Due to high elevation and harsh climate conditions, measurements over the TP used to be sparse. Fortunately, since the 1990s, state-of-the-art observational long-term station networks in the TP and neighboring regions have been established. Four large field experiments since 1996, among many observational activities, are presented in this article. These experiments should greatly help further research on TP land/atmosphere interactions.
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Goswami, B. N., und Soumi Chakravorty. Dynamics of the Indian Summer Monsoon Climate. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228620.013.613.
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Lifeline for about one-sixth of the world’s population in the subcontinent, the Indian summer monsoon (ISM) is an integral part of the annual cycle of the winds (reversal of winds with seasons), coupled with a strong annual cycle of precipitation (wet summer and dry winter). For over a century, high socioeconomic impacts of ISM rainfall (ISMR) in the region have driven scientists to attempt to predict the year-to-year variations of ISM rainfall. A remarkably stable phenomenon, making its appearance every year without fail, the ISM climate exhibits a rather small year-to-year variation (the standard deviation of the seasonal mean being 10% of the long-term mean), but it has proven to be an extremely challenging system to predict. Even the most skillful, sophisticated models are barely useful with skill significantly below the potential limit on predictability. Understanding what drives the mean ISM climate and its variability on different timescales is, therefore, critical to advancing skills in predicting the monsoon. A conceptual ISM model helps explain what maintains not only the mean ISM but also its variability on interannual and longer timescales.The annual ISM precipitation cycle can be described as a manifestation of the seasonal migration of the intertropical convergence zone (ITCZ) or the zonally oriented cloud (rain) band characterized by a sudden “onset.” The other important feature of ISM is the deep overturning meridional (regional Hadley circulation) that is associated with it, driven primarily by the latent heat release associated with the ISM (ITCZ) precipitation. The dynamics of the monsoon climate, therefore, is an extension of the dynamics of the ITCZ. The classical land–sea surface temperature gradient model of ISM may explain the seasonal reversal of the surface winds, but it fails to explain the onset and the deep vertical structure of the ISM circulation. While the surface temperature over land cools after the onset, reversing the north–south surface temperature gradient and making it inadequate to sustain the monsoon after onset, it is the tropospheric temperature gradient that becomes positive at the time of onset and remains strongly positive thereafter, maintaining the monsoon. The change in sign of the tropospheric temperature (TT) gradient is dynamically responsible for a symmetric instability, leading to the onset and subsequent northward progression of the ITCZ. The unified ISM model in terms of the TT gradient provides a platform to understand the drivers of ISM variability by identifying processes that affect TT in the north and the south and influence the gradient.The predictability of the seasonal mean ISM is limited by interactions of the annual cycle and higher frequency monsoon variability within the season. The monsoon intraseasonal oscillation (MISO) has a seminal role in influencing the seasonal mean and its interannual variability. While ISM climate on long timescales (e.g., multimillennium) largely follows the solar forcing, on shorter timescales the ISM variability is governed by the internal dynamics arising from ocean–atmosphere–land interactions, regional as well as remote, together with teleconnections with other climate modes. Also important is the role of anthropogenic forcing, such as the greenhouse gases and aerosols versus the natural multidecadal variability in the context of the recent six-decade long decreasing trend of ISM rainfall.
Buchteile zum Thema "Anthropogenic signal"
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Florio Furno, Matteo, Davide Ferrero, Anna Poli, Valeria Prigione, Maria Tuohy, Matteo Oliva, Carlo Pretti und Giovanna Cristina Varese. „Fungi from the sediments of the harbour of Livorno as potential bioremediation agents“. In Ninth International Symposium “Monitoring of Mediterranean Coastal Areas: Problems and Measurement Techniques”, 667–76. Florence: Firenze University Press, 2022. http://dx.doi.org/10.36253/979-12-215-0030-1.63.
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The harbour's sediments are among the biotypes most affected by contamination by pollutants due to anthropogenic activities. The porpoise of this work is to perform a preliminary screening on 74 fungi previously isolated in the polluted sediments of the harbour of Livorno, to identify those endowed with oxidative capabilities and to evaluate the potential producers of metabolites or enzymes of interest, for potential applications in future environmental bioremediation. The results have shown that 26 (35.1%) out of 74 tested fungi produced positive oxidation signal on at least one media
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Oswald, Julie N., Christine Erbe, William L. Gannon, Shyam Madhusudhana und Jeanette A. Thomas. „Detection and Classification Methods for Animal Sounds“. In Exploring Animal Behavior Through Sound: Volume 1, 269–317. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-97540-1_8.
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AbstractClassification of the acoustic repertoires of animals into sound types is a useful tool for taxonomic studies, behavioral studies, and for documenting the occurrence of animals. Classification of acoustic repertoires enables the identification of species, age, gender, and individual identity, correlations between sound types and behavior, the identification of changes in vocal behavior over time or in response to anthropogenic noise, comparisons between the repertoires of populations living in different geographic regions and environments, and the development of software tools for automated signal processing. Techniques for classification have evolved over time as technical capabilities have expanded. Initially, researchers applied qualitative methods, such as listening and visually discerning sounds in spectrograms. Advances in computer technology and the development of software for the automatic detection and classification of sounds have allowed bioacousticians to quickly find sounds in recordings, thus significantly reducing analysis time and enabling the analysis of larger datasets. In this chapter, we present software algorithms for automated signal detection (based on energy, Teager–Kaiser energy, spectral entropy, matched filtering, and spectrogram cross-correlation) as well as for signal classification (e.g., parametric clustering, principal component analysis, discriminant function analysis, classification trees, artificial neural networks, random forests, Gaussian mixture models, support vector machines, dynamic time-warping, and hidden Markov models). Methods for evaluating the performance of automated tools are presented (i.e., receiver operating characteristics and precision-recall) and challenges with classifying animal sounds are discussed.
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McGregor, Peter K., Andrew G. Horn, Marty L. Leonard und Frank Thomsen. „Anthropogenic Noise and Conservation“. In Animal Signals and Communication, 409–44. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-41494-7_14.
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Jakab, Gusztáv, Péter Majkut, Imola Juhász, Sándor Gulyás, Pál Sümegi und Tünde Törőcsik. „Palaeoclimatic signals and anthropogenic disturbances from the peatbog at Nagybárkány (North Hungary)“. In Palaeolimnological Proxies as Tools of Environmental Reconstruction in Fresh Water, 87–106. Dordrecht: Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-3387-1_5.
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Sepp, Tuul, Kevin J. McGraw und Mathieu Giraudeau. „Urban Sexual Selection“. In Urban Evolutionary Biology, 234–52. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198836841.003.0015.
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Human-modified habitats can present both challenges and opportunities for wild animals. Changes in the environment caused by urbanization can affect who survives and reproduces in wild animal populations. Accordingly, we can expect that changes in sexual selection pressures may occur in response to urbanization. Changes in sexually selected traits like bird song and colouration have been one of the main thrusts of urban ecology in recent decades. However, studies to date have focused on describing changes in sexual phenotypes in response to urban environmental change, and knowledge about genetic/microevolutionary change is lacking. Also, while some signalling modalities have been well studied and linked to human activities (e.g., changes in auditory signals in response to anthropogenic noise), others have received comparatively less attention in this context (e.g., effects of air pollution on chemical signalling). In addition, the focus has been mainly on the signal sender, instead of the signal receiver, thereby missing an important side of sexual selection. This chapter reviews the evidence that sexual selection pressures and sexually selected traits have been impacted by urban environments, with attention to the potential for rapid adaptive and plastic shifts in traits of signallers and receivers. It explores the possibilities that urbanization causes evolutionary change and speciation in wild animal populations through sexual selection. Finally, it provides new ideas for future studies to explore these questions and especially the evolution of female preferences in urban environments.
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Woods, Rebecca J. H. „A Breed in Any Other Place“. In The Herds Shot Round the World. University of North Carolina Press, 2017. http://dx.doi.org/10.5149/northcarolina/9781469634661.003.0002.
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This chapter explores “native” British breeds within the context of agricultural improvement at the turn of the nineteenth century, arguing that the idea of a native breed arose at the same time and in opposition to that of an “improved” breed. Breeds were understood to encompass the relationship between heredity, anthropogenic selection, and the influence of climate or environment, although which of these factors was understood to take precedence could and did vary. As breeders increasingly selected their animals for early maturity, meatiness, or particular kinds of wool in the case of sheep in conformation with market imperatives, “native” came to signal a type of livestock defined more by its relationship to a particular place within Great Britain than by its degree of breeding. A growing propensity for moving animals from place to place, and combining existing breeds into new types of livestock, such as Shorthorn cattle or New Leicester sheep, informed these developments.
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Pörtner, Hans-O., und Magda Gutowska. „Effects of Ocean Acidification on Nektonic Organisms“. In Ocean Acidification. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199591091.003.0013.
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The average surface-ocean pH is reported to have declined by more than 0.1 units from the pre-industrial level ( Orr et al. 2005 ), and is projected to decrease by another 0.14 to 0.35 units by the end of this century, due to anthropogenic CO2 emissions (Caldeira and Wickett 2005 ; see also Chapters 3 and 14). These global-scale predictions deal with average surface-ocean values, but coastal regions are not well represented because of a lack of data, complexities of nearshore circulation processes, and spatially coarse model resolution (Fabry et al. 2008 ; Chapter 3 ). The carbonate chemistry of coastal waters and of deeper water layers can be substantially different from that in surface water of offshore regions. For instance, Frankignoulle et al. ( 1998 ) reported pCO2 (note 1) levels ranging from 500 to 9400 μatm in estuarine embayments (inner estuaries) and up to 1330 μatm in river plumes at sea (outer estuaries) in Europe. Zhai et al. (2005) reported pCO2 values of > 4000 μatm in the Pearl River Estuary, which drains into the South China Sea. Similarly, oxygen minimum layers show elevated pCO2 levels, associated with the degree of hypoxia (Millero 1996). These findings suggest that some coastal and mid-water animals, both pelagic and benthic, are regularly experiencing hypercapnic hypercapnic conditions (i.e. elevated pCO2 levels), that reach beyond those projected in the offshore surface ocean. These organisms might, therefore, be preadapted to relatively high ambient pCO2 levels. The anthropogenic signal will nonetheless be superimposed on the pre-existing natural variability. These phenomena lead to the question of whether future changes in the ocean’s carbonate chemistry pose a serious problem for marine organisms. Those with calcareous skeletons or shells, such as corals and some plankton, have been at the centre of scientific interest. However, elevated CO2 levels may also have detrimental effects on the survival, growth, and physiology of marine animals more generally (Pörtner and Reipschläger 1996; Seibel and Fabry 2003; Fabry et al. 2008; Pörtner 2008; Melzner et al. 2009a).
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Singh, Garima, Sachin Kumar, Kalpana Chaudhary und Gaurav Sharma. „Anthropogenic noise affect the bird song frequency and behavioral response“. In Birds - Conservation, Research and Ecology [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.1001351.
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Now a days, as anthropological disturbance increasing in animal’s life, they are adjusting their nature to novel environment. Especially the past few decades, disturbing the integrity of natural ecosystems. Birds has also severe constrain on vocal communication by interfering with selection of acoustics signals. According to recent findings revealed that urban bird’s song with higher- frequency comparison to non- urban habitats. Urban birds may produce higher amplitudes. It impacts on song produce by male in breeding season which affects behavior as well as sexual selection. In this studies variation in song of urban bird and nonurban bird will be found, may varies due to anthropological disturbance, additional responses will be found for changes in reproductive success and changes in vocal communication. Noise from Urban area affect negatively to bird fitness with their communication and for instance, activity related to breeding also bad impact on predator detection. It influence also local distribution pattern as well as bird communities due to continue exposure. Sometimes birds can survive with urban noise, mechanism remain unknown. Here, I Focused on relation between firstly anthropogenic noise and bird richness secondly noise level and song modification then species noise tolerance and detection frequency. Recording will be collected from two type of habitat, one is having heavy anthropogenic noise and another from where habitat have less anthropogenic disturbance. This kind of noise may hamper recognition of song by female, makes difficulties in territory marking and also affects to maintain pair bond in birds. Studies on the quantification and documentation of acoustical characteristics and structural variability in birdsong provide substantial information on its conceptual and empirical significance. Songs may vary at local level in neighboring groups of birds and level of variations depend on selection, based on various behavioral and ecological factors. So, it is important to understand the vocal communication for successful breeding for the conservation and for maintain a balance within ecosystem.
Konferenzberichte zum Thema "Anthropogenic signal"
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Chen, Lei, Zhao Zhao, Ning Li und Zhiyong Xu. „An anthropogenic sound suppression method for acoustic diversity index“. In International Conference on Signal Processing and Communication Technology (SPCT 2021), herausgegeben von Liyi Zhang und Ting Yang. SPIE, 2022. http://dx.doi.org/10.1117/12.2631850.
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Skrypitsyna, Tatyana, Vladimir V. Kurkov, Denis V. Zhuravlev, Vladimir A. Knyaz und Anzhela V. Batasova. „Study of the hidden ancient anthropogenic landscapes using digital models of microtopography“. In Image and Signal Processing for Remote Sensing XXVI, herausgegeben von Claudia Notarnicola, Fabio Bovenga, Lorenzo Bruzzone, Francesca Bovolo, Jon Atli Benediktsson, Emanuele Santi und Nazzareno Pierdicca. SPIE, 2020. http://dx.doi.org/10.1117/12.2572995.
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Rodriguez-Camacho, Jesus, David Blanco-Navarro, Juan Franciso Gomez-Lepera, Jesus Fornieles-Callejon und M. Carmen Carrion. „Separation of Anthropogenic Noise and Extremely Low Frequency Natural Magnetic Field Using Statistical Features“. In 2018 26th European Signal Processing Conference (EUSIPCO). IEEE, 2018. http://dx.doi.org/10.23919/eusipco.2018.8553019.
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Adnan, Nor Aizam, Peter M. Atkinson, Zaharah Mohd Yusoff und Abdul Rauf Abdul Rasam. „Climate variability and anthropogenic impacts on a semi-distributed monsoon catchment runoff simulations“. In 2014 IEEE 10th International Colloquium on Signal Processing & its Applications (CSPA). IEEE, 2014. http://dx.doi.org/10.1109/cspa.2014.6805743.
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Reznik, A. L., A. A. Soloviev und A. V. Torgov. „Improving the spatial resolution of digital images and video sequences using subpixel scanning“. In Spatial Data Processing for Monitoring of Natural and Anthropogenic Processes 2021. Crossref, 2021. http://dx.doi.org/10.25743/sdm.2021.44.67.029.
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High-performance method for improving the resolution of digital images and video sequences based on minimum-variance signal reconstruction are considered. A distinctive feature of the developed algorithms is that they allow (with the availability of modern computing power) to obtain improved images and video in “real time”.
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Dagurov, P. N., A. V. Dmitriev, T. N. Chimitdorzhiev, A. K. Baltukhaev und I. I. Kirbizhekova. „Backscatter analysis of C-band radar signals using Sentinel-1 multitemporal data (test site near lake Baikal)“. In Spatial Data Processing for Monitoring of Natural and Anthropogenic Processes 2021. Crossref, 2021. http://dx.doi.org/10.25743/sdm.2021.71.20.007.
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The results of the analysis of multitemporal data of the Sentinel-1 radar for the test site near Lake Baikal are presented. The analysis of the seasonal dependences of backscattering from the soil is carried out. The connection between the signal level and the processes of freezing and thawing and temperature values has been established.
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Kosykh, V. P., G. I. Gromilin und N. S. Yakovenko. „Joint processing of images in two spectral channels for small objects detecting“. In Spatial Data Processing for Monitoring of Natural and Anthropogenic Processes 2021. Crossref, 2021. http://dx.doi.org/10.25743/sdm.2021.28.23.019.
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The article is devoted to the problem of detecting low contrast small-sized objects in two-color images with a powerful spatially non-stationary background. An increase of the detecting reliability is achieved through a combination of three factors: attenuation of the background based on the construction of its locally stationary model; improving the estimation of model parameters by excluding statistically significant outliers from the initial data; joint processing of two-color images with a weakened background component. A method of constructing a linear boundary for detecting a useful signal in a two-dimensional space is proposed. The performance characteristics of a two-channel detector of small-sized objects are presented.
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Strow, L. Larrabee. „A Signal-Processing Approach for the Retrieval of Global Tropospheric CO Using the Atmospheric Infrared Sounder (AIRS)“. In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/orsa.1993.the.9.
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One goal of the Earth Observing Systems (EOS) is to measure concentrations of key atmospheric gases on a global scale in order to understand biogeochemical cycles in both the natural, unpolluted atmosphere, and in regions where anthropogenic activities have perturbed concentrations of gas-phase species. A particular concern in tropospheric chemistry is that increasing levels of carbon monoxide (CO) may lead to a decrease in atmospheric hydroxyl (OH) which would reduce the atmosphere's ability to scavenge other trace gases.
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Alyokhina, A. E., D. S. Rusin, E. V. Dmitriev und A. N. Safonova. „Neural network texture segmentation of satellite images of woodlands using the U-net model“. In Spatial Data Processing for Monitoring of Natural and Anthropogenic Processes 2021. Crossref, 2021. http://dx.doi.org/10.25743/sdm.2021.70.49.004.
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With the advent of space equipment that allows obtaining panchromatic images of ultra-high spatial resolution (< 1 m) there was a tendency to develop methods of thematic processing of aerospace images in the direction of joint use of textural and spectral features of the objects under study. In this paper, we consider the problem of classification of forest canopy structures based on textural analysis of multispectral and panchromatic images of Worldview-2. Traditionally, a statistical approach is used to solve this problem, based on the construction of distributions of the common occurrence of gray gradations and the calculation of statistical moments that have significant regression relationships with the structural parameters of stands. An alternative approach to solving the problem of extracting texture features is based on frequency analysis of images. To date, one of the most promising methods of this kind is based on wavelet scattering. In comparison with the traditionally applied approaches based on the Fourier transform, in addition to the characteristic signal frequencies, the wavelet analysis allows us to identify characteristic spatial scales, which is fundamentally important for the textural analysis of spatially inhomogeneous images. This paper uses a more general approach to solving the problem of texture segmentation using the convolutional neural network U-net. This architecture is a sequence of convolution-pooling layers. At the first stage, the sampling of the original image is lowered and the content is captured. At the second stage, the exact localization of the recognized classes is carried out, while the discretization is increased to the original one. The RMSProp optimizer was used to train the network. At the preprocessing stage, the contrast of fragments is increased using the global contrast normalization algorithm. Numerical experiments using expert information have shown that the proposed method allows segmenting the structural classes of the forest canopy with high accuracy.
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Khairallah, Yara, Tarek Houri, Georges Haddad, Bilal Osta, Danny Romanos und Rajaa Fakhoury. „Can the damage caused by anthropogenic activities on Urginea maritima in Bentael natural reserve be a signal of health problems?“ In 2016 3rd Middle East Conference on Biomedical Engineering (MECBME). IEEE, 2016. http://dx.doi.org/10.1109/mecbme.2016.7745396.
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Hackbarth, Carolyn, und Rebeca Weissinger. Water quality in the Northern Colorado Plateau Network: Water years 2016–2018 (revised with cost estimate). National Park Service, November 2023. http://dx.doi.org/10.36967/nrr-2279508.
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Water-quality monitoring in National Park Service units of the Northern Colorado Plateau Network (NCPN) is made possible through partnerships between the National Park Service Inventory & Monitoring Division, individual park units, the U.S. Geological Survey, and the Utah Division of Water Quality. This report evaluates data from site visits at 62 different locations on streams, rivers, and reservoirs in or near ten NCPN park units between October 1, 2015 and September 30, 2018. Data are compared to state water-quality standards for the purpose of providing information to park managers about potential water-quality problems. The National Park Service does not determine the regulatory status of surface waters; state water quality agencies determine whether waters comply with the Clean Water Act. Evaluation of water-quality parameters relative to state water-quality standards indicated that 17,997 (96.8%) of the 18,583 total designated beneficial-use evaluations completed for the period covered in this report met state water-quality standards. The most common exceedances or indications of impairment, in order of abundance, were due to elevated nutrients, elevated bacteria (E. coli), elevated water temperature, elevated trace metals, elevated total dissolved solids (and sulfate), elevated pH, and low dissolved oxygen. While some exceedances were recurring and may have been caused by human activities in the watersheds, many were due to naturally occurring conditions characteristic of the geographic setting. This is most apparent with phosphorus, which can be introduced into surface water bodies at elevated levels by natural weathering of the geologic strata found throughout the Colorado Plateau. Higher phosphorus concentrations could also be attributed to anthropogenic activities that can accelerate erosion and transport of phosphorus. Some activities that can increase erosional processes include grazing, logging, mining, pasture irrigation, and off-highway vehicle (OHV) use. Exceedances for total phosphorus were common occurrences at nine out of ten NCPN park units, where at least one site in each of these parks had elevated phosphorus concentrations. At these sites, high levels of nutrients have not led to algal blooms or other signs of eutrophication. Sites monitored in Arches National Park (NP), Black Canyon of the Gunnison NP (BLCA), Bryce Canyon NP (BRCA), Capitol Reef NP (CARE), Curecanti National Recreation Area (CURE), Dinosaur National Monument (DINO), and Zion NP (ZION) all had E. coli ex-ceedances that could be addressed by management actions. While many of these sites already have management actions underway, some of the actions necessary to bring these waters into compliance are beyond the control of the National Park Service. Changes to agricultural practices to improve water quality involves voluntary participation by landowners and/or grazing permittees and their respective states. This could be the case with lands upstream of several parks with E. coli contamination issues, including Red Rock Canyon (BLCA); Sul-phur, Oak, and Pleasant creeks (CARE); Blue Creek and Cimarron River (CURE); Brush and Pot creeks (DINO); and North Fork Virgin River (ZION). Issues with E. coli contamination at Yellow Creek (BRCA) seemed to be resolved after the park boundary fence downstream of the site was repaired, keeping cattle out of the park. At North Fork Virgin River, E. coli exceedances have been less frequent since the State of Utah worked with landowners and grazing permittees to modify agricultural practices. Continued coordination between the National Park Service, state agencies, and local landowners will be necessary to further re-duce E. coli exceedances and, in turn, improve public health and safety in these streams. Selenium concentrations in Red Rock Canyon (BLCA) continued to exceed the state aquat-ic-life standard at both the upstream and downstream sites. Although selenium weathers naturally from bedrock and...