Plasticity in habitat use of two native Ponto-Caspian gobies, Proterorhinus semilunaris and Neogobius fluviatilis: implications for invasive populations

The Ponto-Caspian region is an important source area for some invasive gobiid fishes. These fishes have colonised several freshwater ecosystems in Europe, as well as in North America. As knowledge on their habitat utilisation in their native range remains limited, the seasonal habitat uses of Western tubenose goby, Proterorhinus semilunaris and monkey goby Neogobius fluviatilis were studied in four natural lakes in the Marmara Region (NW Turkey). Habitat use of both species was highly variable between the lakes and seasons, with P. semilunaris showing higher plasticity. In general, the main habitats used by P. semilunaris were shallow waters in littoral areas that had vegetation cover, whereas N. fluviatilis consistently used sandy substratum in deeper waters that lacked vegetation. These results suggested there was high plasticity in the habitat utilisation of these two gobiids, especially in P. semilunaris, which potentially facilitates their ability to establish and invade novel environments. The habitats that are especially vulnerable to P. semilunaris invasion are medium size substrates which provide individuals with sufficient interstitial space for refuge. Waters providing differing habitats, such as sandy substrata, might inhibit their colonisation, but are potentially more vulnerable to N. fluviatilis invasion.

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Summer stream habitat preferences of Nunavik anadromous Arctic char (Salvelinus alpinus) fry and parr

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2021-0119 ◽

2022 ◽

Author(s):

Véronique Dubos ◽

André St-Hilaire ◽

Normand E Bergeron

Keyword(s):

Habitat Use ◽

Salvelinus Alpinus ◽

Habitat Preferences ◽

Arctic Region ◽

Arctic Char ◽

The Arctic ◽

Stream Habitat ◽

Physical Habitat ◽

High Plasticity ◽

Slow Velocity

Arctic char is a fish species known to occupy diverse habitats within the Arctic region. However, summer habitat use during the juvenile stage of the anadromous form is largely unknown. The present study aims to characterize fry and parr summer habitat preferences. Surveys were conducted by electrofishing, associated with physical habitat characterization on several rivers of the Ungava Bay, Nunavik, Canada. At the microhabitat and station scales, fry showed significant habitat preferences for shallow water and slow velocity. At the mesohabitat scale, fry showed a significant habitat selectivity for riffles. This habitat selectivity implies that habitat models can be built to evaluate the potential of habitat suitability for Arctic char fry. However, no significant habitat selectivity was found for parr. Parr size was nonetheless positively correlated with velocity, which was found to be a limitative factor for juvenile habitat use. This first attempt at modeling juvenile anadromous Arctic char habitat in rivers emphasizes the importance of selecting an appropriate spatial scale and reiterates the fact that parr showed relatively high plasticity in stream habitat selection.

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Velocity changes across the Ganos segment of the North Anatolian Fault Zone in NW Turkey from systematic variations in body wave arrival times

10.5194/egusphere-egu21-8152 ◽

2021 ◽

Author(s):

Esref Yalcinkaya ◽

Marco Bohnhoff ◽

Patricia Martinez-Garzon ◽

Ethem Görgün ◽

Ali Pınar ◽

...

Keyword(s):

Body Wave ◽

Waveform Analysis ◽

Marmara Region ◽

Rupture Directivity ◽

Data Set ◽

High Resolution Data ◽

Arrival Times ◽

The North ◽

Nw Turkey ◽

Geological Units

Imaging and characterizing transform fault sections that are capable to produce large earthquakes is crucial for evaluating seismic hazard and subsequent risk for nearby population centers. The Marmara Fault near the megacity of Istanbul is one of the best defined seismic gaps in the world and its complexity is captured by seismological, geodetic and geological data. A local dense seismic array (MONGAN) provides a high resolution data set allowing to image the Ganos fault separating two different geological units in the western Marmara region. First results of the waveform analysis from this array present systematic early-phase arrivals at the seismic stations located on the northern block of the Ganos fault which comprises geological units including older and more compact materials than that of the southern block. This difference in the arrival times causes the earthquake epicenters to shift further north than the real locations. In this preliminary results, the early-arrivals will be evaluated according to source azimuths and distances, and possible earth models and wave paths will be discussed. The results have implications for rupture directivity during future earthquakes as input for hazard and risk models for the Marmara region.

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Near-fault seismic monitoring reveals the long-lasting activation of a local fault in the Marmara region controlled by slow slip

10.5194/egusphere-egu21-7710 ◽

2021 ◽

Author(s):

Patricia Martínez-Garzón ◽

Virginie Durand ◽

Stephan Bentz ◽

Taylan Turkmen ◽

Grzegorz Kwiatek ◽

...

Keyword(s):

Temporal Distribution ◽

Marmara Region ◽

Slow Slip ◽

Fault Rupture ◽

Aseismic Slip ◽

Seismic Sequences ◽

Near Fault ◽

Aftershock Sequences ◽

Nw Turkey ◽

Different Characteristics

Recent laboratory and field observations show that fault seismic and aseismic slip may occur concurrently. Here, we combine microseismicity recordings from a temporary near-fault seismic network (SMARTnet) and borehole strainmeter data from the eastern Marmara region in NW Turkey to track seismic and aseismic deformation around the hypocentral region of a MW 4.5 earthquake that occurred in 2018. The strainmeter data show a clear strain signal transient starting at the time of the MW 4.5 event and lasting for about 150 days. We study about 1,200 microseismic events following the mainshock within and beyond the mainshock fault rupture. The temporal distribution of the seismicity reveals a strong temporal clustering, including four semi-periodic seismic sequences each containing more than 50 events in two days. Two seismic sequences occurred during the strain transient showing different characteristics compared to two sequences occurring afterwards. Seismicity occurring during the transient displayed typical characteristics driven by aseismic slip, such as the activation of a broader region from the mainshock, and the absence of a clear mainshock in each sequence. Seismic sequences occurring after the transient correspond to typical mainshock-aftershock sequences and activated a region closer to the original MW 4.5 mainshock. We suggest post-strain transient seismicity originate from stress redistribution and breaking of remaining asperities. Our observations from a newly installed combined dense seismic and strainmeter network in the eastern Sea of Marmara region allows identifying repeated triggering of aseismic transients within an observation period of three years suggesting these may occur more often than previously thought.

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The Importance of Riparian Forest Cover to the Ecological Status of Agricultural Streams in a Nationwide Assessment

Water Resources Management ◽

10.1007/s11269-021-02923-2 ◽

2021 ◽

Author(s):

Mikko Tolkkinen ◽

Saku Vaarala ◽

Jukka Aroviita

Keyword(s):

Land Use ◽

Forest Cover ◽

Riparian Forest ◽

Ecological Status ◽

Freshwater Ecosystems ◽

Agricultural Landscapes ◽

Riparian Forests ◽

Independent Effect ◽

Medium Size ◽

Positive Effect

AbstractForested riparian corridors are a key management solution for halting the global trend of declining ecological status of freshwater ecosystems. There is an increasing body of evidence related to the efficacy of these corridors at the local scale, but knowledge is inadequate concerning the effectiveness of riparian forests in terms of protecting streams from harmful impacts across larger scales. In this study, nationwide assessment results comprising more than 900 river water bodies in Finland were used to examine the importance of adjacent land use to river ecological status estimates. Random forest models and partial dependence functions were used to quantify the independent effect of adjacent land use on river ecological status after accounting for the effects of other factors. The proportion of adjacent forested land along a river had the strongest independent positive effect on ecological status for small to medium size rivers that were in agricultural landscapes. Ecological quality increased by almost one status class when the adjacent forest cover increased from 10 to 60%. In contrast, for large rivers, adjacent forested land did not show an independent positive effect on ecological status. This study has major implications for managing river basins to achieve the EU Water Framework Directive (WFD) goal of obtaining good ecological status of rivers. The results from the nationwide assessment demonstrate that forested riparian zones can have an independent positive effect on the ecological status of rivers, indicating the importance of riparian forests in mitigating the impacts of catchment-level stressors. Therefore, forested buffer zones should be more strongly considered as part of river basin management.

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The October 20, 2006 Manyas (ML=5.2) and October 24, 2006 Gemlik (ML=5.2) earthquakes in the Marmara region (NW Turkey): ground motion characteristics

Annals of Geophysics ◽

10.4401/ag-6524 ◽

2015 ◽

Vol 57 (6) ◽

Author(s):

Esref Yalcinkaya

Keyword(s):

Surface Waves ◽

Ground Motion ◽

Empirical Relation ◽

General Character ◽

Marmara Region ◽

Resonance Frequencies ◽

Nw Turkey ◽

Southern Branch ◽

Motion Characteristics ◽

Northern Branch

In this study, we analyze the ground motion characteristics of October 20, 2006 Manyas (ML=5.2) and October 24, 2006 Gemlik (ML=5.2) earthquakes. Both earthquakes occurred on the southern branch of the North Anatolian Fault Zone in Marmara region, which has a lower seismic hazard relative to the northern branch. The two events are the largest earthquakes on the southern branch recorded by a modern and vast seismological network; therefore their records are valuable to evaluate seismic risk of the region and the understanding of physics of wave propagation. The analysis show that the attenuation of PGAs is very similar for two earthquakes, but they are not represented by the empirical relation obtained for earthquakes occurred on the northern branch. The waveforms of the Gemlik earthquake recorded by BYTNet array indicate an EW rupture orientation with right-lateral slip which fits to the general character of the southern branch. Ground motions at the stations located within basin are strongly influenced by the presence of locally induced surface waves resulting in lengthening of significant shaking duration with respect to a nearby ridge site. Surface wave characteristics are very similar for the Manyas and Gemlik earthquakes, but variations are observed on components which may be related to 3D basin geometry. Resonance frequencies of the surface waves generated within basin are very close to the 1D site resonances at the stations obtained from H/V ratios of S waves. The resonance frequency is about 0.2 Hz within the large Bursa Plain, whereas it increases to about 0.9 Hz within the smaller Gemlik Plain.

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Citizen science reveals unexpected solute patterns in semiarid river networks

PLoS ONE ◽

10.1371/journal.pone.0255411 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0255411

Author(s):

Erin Fleming Jones ◽

Rebecca J. Frei ◽

Raymond M. Lee ◽

Jordan D. Maxwell ◽

Rhetta Shoemaker ◽

...

Keyword(s):

Citizen Science ◽

Major Ions ◽

Management Strategies ◽

Source Area ◽

Nutrient Status ◽

Freshwater Ecosystems ◽

High Variability ◽

Nitrogen And Phosphorus ◽

Phosphorus Species ◽

Relative Water

Human modification of water and nutrient flows has resulted in widespread degradation of aquatic ecosystems. The resulting global water crisis causes millions of deaths and trillions of USD in economic damages annually. Semiarid regions have been disproportionately affected because of high relative water demand and pollution. Many proven water management strategies are not fully implemented, partially because of a lack of public engagement with freshwater ecosystems. In this context, we organized a large citizen science initiative to quantify nutrient status and cultivate connection in the semiarid watershed of Utah Lake (USA). Working with community members, we collected samples from ~200 locations throughout the 7,640 km2 watershed on a single day in the spring, summer, and fall of 2018. We calculated ecohydrological metrics for nutrients, major ions, and carbon. For most solutes, concentration and leverage (influence on flux) were highest in lowland reaches draining directly to the lake, coincident with urban and agricultural sources. Solute sources were relatively persistent through time for most parameters despite substantial hydrological variation. Carbon, nitrogen, and phosphorus species showed critical source area behavior, with 10–17% of the sites accounting for most of the flux. Unlike temperate watersheds, where spatial variability often decreases with watershed size, longitudinal variability showed an hourglass shape: high variability among headwaters, low variability in mid-order reaches, and high variability in tailwaters. This unexpected pattern was attributable to the distribution of human activity and hydrological complexity associated with return flows, losing river reaches, and diversions in the tailwaters. We conclude that participatory science has great potential to reveal ecohydrological patterns and rehabilitate individual and community relationships with local ecosystems. In this way, such projects represent an opportunity to both understand and improve water quality in diverse socioecological contexts.

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Atmospheric circulation types in Marmara Region (NW Turkey) and their influence on precipitation

International Journal of Climatology ◽

10.1002/joc.4122 ◽

2014 ◽

Vol 35 (8) ◽

pp. 1810-1820 ◽

Cited By ~ 14

Author(s):

H. Baltacı ◽

O. M. Göktürk ◽

T. Kındap ◽

A. Ünal ◽

M. Karaca

Keyword(s):

Atmospheric Circulation ◽

Marmara Region ◽

Circulation Types ◽

Nw Turkey

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Spatial environmental variability of natural markers and habitat use of Cathorops spixii in a neotropical estuary from otolith chemistry

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315420000752 ◽

2020 ◽

Vol 100 (5) ◽

pp. 783-793

Author(s):

Barbara Maichak de Carvalho ◽

Daniel Vicente Pupo ◽

Alejandra Vanina Volpedo ◽

Jorge Pisonero ◽

Ana Méndez ◽

...

Keyword(s):

Habitat Use ◽

Environmental Variability ◽

Change Point Analysis ◽

Salinity Range ◽

High Plasticity ◽

Use Patterns ◽

Potential Habitat ◽

Point Analysis ◽

Icp Ms ◽

Migratory Patterns

AbstractThe goal of this study was to study the distribution of potential habitat markers (Sr/Ca, Ba/Ca, Mn/Ca and Li/Ca) in water from the Paranaguá Estuarine Complex (Brazil) and to study habitat use patterns of Cathorops spixii through ontogeny employing otolith microchemistry. Fish were caught from three sampling sites while water samples were collected at eight stations covering a salinity range from 4.5–33. Elemental concentrations in otolith and water were determined by LA-ICP-MS and ICP-MS, respectively. When the relationship between salinity and elements or ratios in water was studied, significant positive relationships were found for Sr, Li, Ca, Sr/Ca, and negative for Ba, Mn, Ba/Ca and Mn/Ca (P < 0.05). No relationship was observed between water Li/Ca and salinity. A significant positive correlation was found between otolith edge Sr/Ca and salinity (r = 0.63; P < 0.05), positioning this ratio as the best natural tag for reconstructing environmental histories of C. spixii. Change point analysis (CPA) based on otolith Sr/Ca signature through ontogeny revealed potential migrations between environments with different salinity. According to CPA, the number of displacements among different salinities ranged from 3–9 (6.1 ± 1.9), suggesting high plasticity in the migratory patterns. Ba/Ca, Li/Ca and Mn/Ca peaks were observed on the outer margin of the primordium, and could be influenced by physiological, environmental and maternal factors.

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The Effect of Site-Specific Design Spectrum on Earthquake-Building Parameters: A Case Study from the Marmara Region (NW Turkey)

Applied Sciences ◽

10.3390/app10207247 ◽

2020 ◽

Vol 10 (20) ◽

pp. 7247

Author(s):

Ercan Işık ◽

Aydın Büyüksaraç ◽

Yunus Levent Ekinci ◽

Mehmet Cihan Aydın ◽

Ehsan Harirchian

Keyword(s):

Reinforced Concrete ◽

Structural Parameters ◽

Earthquake Ground Motion ◽

Marmara Region ◽

Specific Design ◽

Site Specific ◽

Reinforced Concrete Building ◽

Design Spectrum ◽

Nw Turkey ◽

Concrete Building

The Marmara Region (NW Turkey) has experienced significant earthquakes (M > 7.0) to date. A destructive earthquake is also expected in the region. To determine the effect of the specific design spectrum, eleven provinces located in the region were chosen according to the Turkey Earthquake Building Code updated in 2019. Additionally, the differences between the previous and updated regulations of the country were investigated. Peak Ground Acceleration (PGA) and Peak Ground Velocity (PGV) were obtained for each province by using earthquake ground motion levels with 2%, 10%, 50%, and 68% probability of exceedance in 50-year periods. The PGA values in the region range from 0.16 to 0.7 g for earthquakes with a return period of 475 years. For each province, a sample of a reinforced-concrete building having two different numbers of stories with the same ground and structural characteristics was chosen. Static adaptive pushover analyses were performed for the sample reinforced-concrete building using each province’s design spectrum. The variations in the earthquake and structural parameters were investigated according to different geographical locations. It was determined that the site-specific design spectrum significantly influences target displacements for performance-based assessments of buildings due to seismicity characteristics of the studied geographic location.

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Molecular detection of hepatotoxic cyanobacteria in inland water bodies of the Marmara Region, Turkey

Advances in Oceanography and Limnology ◽

10.4081/aiol.2017.6394 ◽

2017 ◽

Vol 8 (1) ◽

Cited By ~ 4

Author(s):

Latife Köker ◽

Reyhan Akçaalan ◽

Meriç Albay ◽

Brett A. Neilan

Keyword(s):

Environmental Samples ◽

Molecular Detection ◽

Freshwater Ecosystems ◽

Molecular Methods ◽

Marmara Region ◽

Microcystin Synthetase ◽

Toxic Cyanobacteria ◽

Mcye Gene ◽

Microcystin Production ◽

Inland Water Bodies

Blooms of cyanobacteria are an increasingly frequent phenomenon in freshwater ecosystems worldwide as a result of eutrophication. Many species can produce hepatotoxins that cause severe health hazards to humans. The aim of this study was to identify the bloom forming cyanobacteria species by molecular methods and to amplify genes responsible for hepatotoxin biosynthesis from the environmental samples and isolated strains of cyanobacteria from Küçükçekmece Lagoon, Sapanca, İznik, Manyas and Taşkısı Lakes. A total of 10 bloom samples and 11 isolated strains were examined and Microcystis spp., Planktothrix spp., Nodularia spumigena, Anabaenopsis elenkinii, Sphaerospermopsis aphanizomenoides, Cylindrospermopsis raciborskii were identified. Hepatotoxin genes were detected in 60% of the bloom samples and 45% of the strains. Two Microcystis strains were obtained from Küçükçekmece Lagoon. While the strain assigned to Microcystis flosaquae was non-toxic, Microcystis aeruginosa strain produced microcystin. According to PCR results, the M. aeruginosa and Planktothrix agardhii bloom samples of Küçükçekmece Lagoon contained the microcystin synthetase gene E (mcyE) indicative of microcystin production, however, no microcystin was detected by HPLC. The mcyE gene was also found in Microcystis wesenbergii isolated from Taşkısı Lake, and in all Planktothrix rubescens bloom samples from Sapanca Lake. To our knowledge, this is the first detailed study for identifiying different toxic cyanobacteria species and their hepatotoxin production from several waterbodies in Turkey using molecular methods.

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