The non-indigenous Oithona davisae in a Mediterranean transitional environment: coexistence patterns with competing species

AbstractThe Venice lagoon (VL) has been recognized as a hot spot of introduction of non-indigenous species (NIS), due to several anthropogenic factors and environmental stressors that combined may facilitate NIS invasions. In the last decades an increasing number of zooplankton NIS have been observed in the VL. This work aims to provide a picture of the annual cycle and distribution of the recently recorded non-indigenous copepod Oithona davisae, considering the coexistence patterns with the congeneric resident Oithona nana. Therefore, zooplankton samplings were carried out monthly from August 2016 to July 2017 at five Long-Term Ecological Research LTER stations in the VL. Oithona davisae showed a persistent occurrence throughout the year with the highest abundances in the warm season and in the inner areas, while the congeneric O. nana, showing a different distribution pattern, resulted more abundant near the inlets of the Lagoon, where O. davisae reached the minimum density. Oithona davisae seems to find local conditions that promote its settlement and distribution, especially in the inner and more trophic lagoon sites. In other European coastal embayments or transitional waters, O. davisae occupied the niche left by the indigenous O. nana or can replace this congeneric species through competitive exclusion mechanisms. Our data indicate that, for now, such species replacement has not occurred in the VL. One of the causes is the extreme variety of habitats and niches offered by this environment allowing a balanced coexistence with O. nana and in general with the resident copepod community.

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The Copepod Acartia tonsa Dana in a Microtidal Mediterranean Lagoon: History of a Successful Invasion

Water ◽

10.3390/w11061200 ◽

2019 ◽

Vol 11 (6) ◽

pp. 1200

Author(s):

Elisa Camatti ◽

Marco Pansera ◽

Alessandro Bergamasco

Keyword(s):

Hot Spot ◽

Temporal Trends ◽

Venice Lagoon ◽

Acartia Tonsa ◽

Environmental Stressors ◽

Anthropogenic Factors ◽

Lagoon Of Venice ◽

Before And After ◽

Trophic Network ◽

History Of

The Lagoon of Venice has been recognized as a hot spot for the introduction of nonindigenous species. Several anthropogenic factors as well as environmental stressors concurred to make this ecosystem ideal for invasion. Given the zooplankton ecological relevance related to the role in the marine trophic network, changes in the community have implications for environmental management and ecosystem services. This work aims to depict the relevant steps of the history of invasion of the copepod Acartia tonsa in the Venice lagoon, providing a recent picture of its distribution, mainly compared to congeneric residents. In this work, four datasets of mesozooplankton were examined. The four datasets covered a period from 1975 to 2017 and were used to investigate temporal trends as well as the changes in coexistence patterns among the Acartia species before and after A. tonsa settlement. Spatial distribution of A. tonsa was found to be significantly associated with temperature, phytoplankton, particulate organic carbon (POC), chlorophyll a, and counter gradient of salinity, confirming that A. tonsa is an opportunistic tolerant species. As for previously dominant species, Paracartia latisetosa almost disappeared, and Acartia margalefi was not completely excluded. In 2014–2017, A. tonsa was found to be the dominant Acartia species in the lagoon.

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Is the trend in new introductions of marine non-indigenous species a reliable criterion for assessing good environmental status? Τhe case study of Greece

Mediterranean Marine Science ◽

10.12681/mms.25136 ◽

2020 ◽

Vol 21 (3) ◽

pp. 775

Author(s):

ARGYRO ZENETOS ◽

PARASKEVI K. KARACHLE ◽

MARIA CORSINI-FOKA ◽

VASILIS GEROVASILEIOU ◽

NOMIKI SIMBOURA ◽

...

Keyword(s):

Hot Spot ◽

Aegean Sea ◽

Indigenous Species ◽

The South ◽

Regional Coordination ◽

Environmental Status ◽

Good Environmental Status ◽

Taxonomic Groups ◽

Non Indigenous Species

This study presents the updated status of marine non-indigenous species (NIS) distribution in Greece and investigates trends in new NIS introductions, at both national and subnational level, during 1970-2017. The overall picture shows an increase in new introductions from the 1970s to 2017. The number of unaided introduced species (mainly Lessepsian immigrants) followed an upward trend in the South Aegean Sea until 2017. Similarly, the number of NIS associated with transport-stowaway (NIS introduced mainly via ballast and boat hulls) followed an upward until 2017 in the South Aegean Sea, but also in the Hellenic Levantine coasts. However, these results are greatly affected by a monitoring bias, which appears to be the main factor influencing the number of new NIS introductions reported from Greece and its subnational areas. This monitoring bias, as well as the continuous influx of Lessepsian NIS into the Aegean Sea, constitutes a challenge for Greece as regards setting exact boundaries for areas with or without Good Environmental Status (GES), based on Descriptor 2, primary criterion C1 (D2C1), of the Marine Strategy Framework Directive (MSFD). Dedicated monitoring of marine NIS should be established and be constant in space, time and across taxonomic groups. Prioritization should be given to hot-spot areas of new NIS introductions, such as ports, aquaculture units and marine protected areas. This should be a prerequisite for applying the primary criterion D2C1 of the MSFD properly, at both national and subnational level. Finally, as regards the implementation of D2C1 of the MSDF and setting exact threshold values, we highlight the need for subregional and regional coordination in the Mediterranean.

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MOSAICITY OF THE VEGETATION COVER OF THE KOCHUBEY BIOSPHERE STATION PASTURES

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2020/3/40-42 ◽

1970 ◽

pp. 40-42

Author(s):

М. А. Babaeva ◽

S. V. Osipova

Keyword(s):

Plant Species ◽

Vegetation Cover ◽

Cynodon Dactylon ◽

Plant Cover ◽

Avena Fatua ◽

Living Environment ◽

Anthropogenic Factors ◽

Indigenous Species ◽

Fodder Plants ◽

Falcaria Vulgaris

The regularities of changes in the resistance of different groups of fodder plants to adverse conditions were studied. This is due to the physiological properties that allow them to overcome the harmful effects of the environment. As a result of research species - plant groups with great adaptive potential to the harsh continental semi-desert conditions were identified. Monitoring observation and experimental studies showed too thin vegetation cover as a mosaic, consisting of perennial xerophytic herbs and semishrubs, sod grasses, saltwort and wormwood, as well as ephemera and ephemeroids under the same environmental conditions, depending on various climatic and anthropogenic factors. This is due to the inability or instability of plant species to aggressive living environment. It results in horizontal heterogeneity of the grass stand, division into smaller structures, and mosaic in the vegetation cover of the Kochubey biosphere station. The relative resistance to moderate stress was identified in the following species from fodder plants Agropyron cristatum, A. desertorum, Festuca valesiaca, Cynodon dactylon, Avena fatua; as for strong increasing their abundance these are poorly eaten plant species Artemisia taurica, Atriplex tatarica, Falcaria vulgaris, Veronica arvensis, Arabidopsis thaliana and other. On the site with an increasing pressure in the herbage of phytocenoses the number of xerophytes of ruderal species increases and the spatial structure of the vegetation cover is simplified. In plant communities indigenous species are replaced by adventive plant species. The mosaic of the plant cover of phytocenoses arises due to the uneven distribution in the space of environmental formation, i.e. an edificatory: Salsola orientalis, S. dendroides, Avena fatua, Cynodon dactylon, Artemisia taurica, A. lercheanum, Xanthium spinosum, Carex pachystyli, under which the remaining components of the community adapt. Based on the phytocenotic indicators of pasture phytocenoses it can be concluded that the vegetation cover is in the stage of ecological stress and a decrease in the share of fodder crops and an increase in the number of herbs indicates this fact.

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Meta-analysis on the ecological impacts of widely spread non-indigenous species in the Baltic Sea

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.147375 ◽

2021 ◽

pp. 147375

Author(s):

Henn Ojaveer ◽

Jonne Kotta ◽

Okko Outinen ◽

Heli Einberg ◽

Anastasija Zaiko ◽

...

Keyword(s):

Baltic Sea ◽

Meta Analysis ◽

Ecological Impacts ◽

Indigenous Species ◽

The Baltic Sea ◽

The Baltic ◽

Non Indigenous Species

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Ecological status assessment and non-indigenous species in industrial and fishing harbours of the Gulf of Gabès (central Mediterranean Sea)

Environmental Science and Pollution Research ◽

10.1007/s11356-021-14729-1 ◽

2021 ◽

Author(s):

Nawfel Mosbahi ◽

Jean-Philippe Pezy ◽

Lassad Neifar ◽

Jean-Claude Dauvin

Keyword(s):

Mediterranean Sea ◽

Ecological Status ◽

Indigenous Species ◽

Central Mediterranean ◽

Gulf Of Gabes ◽

Gulf Of Gabès ◽

Central Mediterranean Sea ◽

Ecological Status Assessment ◽

Status Assessment ◽

Non Indigenous Species

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First Record of the Alien Species Procambarus virginalis Lyko, 2017 in Fresh Waters of Sardinia and Insight into Its Genetic Variability

Life ◽

10.3390/life11070606 ◽

2021 ◽

Vol 11 (7) ◽

pp. 606

Author(s):

Daria Sanna ◽

Ilenia Azzena ◽

Fabio Scarpa ◽

Piero Cossu ◽

Angela Pira ◽

...

Keyword(s):

Genetic Variability ◽

Alien Species ◽

Procambarus Clarkii ◽

Mitochondrial Gene ◽

First Record ◽

Indigenous Species ◽

Fresh Waters ◽

Mediterranean Island ◽

Marbled Crayfish ◽

Non Indigenous Species

In the fresh waters of Sardinia (Italy), the non-indigenous crayfish species Procambarus clarkii has been reported from 2005, but, starting from 2019, there have been several reports of a new non-indigenous crayfish in southern and central areas of this Mediterranean island, and its morphology suggests that this species may be the marbled crayfish Procambarus virginalis. Forty-seven individuals of this putative species were analyzed, using the mitochondrial gene Cytochrome c Oxidase subunit I as molecular marker to identify this crayfish and investigate the level of genetic variability within the recently established population. Phylogenetic and phylogeographic analyses were carried out on a dataset including sequences from the Sardinian individuals and from all congenerics available in GenBank. Results showed that the new Sardinian crayfish belong to the species P. virginalis. All the sequences belonging to P. virginalis from European countries are identical, with only few exceptions found among Sardinian individuals. In conclusion, this paper highlights the occurrence of a new further alien species in the Sardinian fresh waters, which are already characterized by the high presence of non-indigenous species.

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Diversity and distribution of large branchiopods in Kiskunság (Hungary) in relation to local habitat and spatial factors: implications for their conservation

Marine and Freshwater Research ◽

10.1071/mf08154 ◽

2008 ◽

Vol 59 (10) ◽

pp. 940 ◽

Cited By ~ 14

Author(s):

Liesbet Boven ◽

Bram Vanschoenwinkel ◽

Els R. De Roeck ◽

Ann Hulsmans ◽

Luc Brendonck

Keyword(s):

Species Richness ◽

Hot Spot ◽

Local Environment ◽

Common Species ◽

Habitat Diversity ◽

Ecological Knowledge ◽

Species Dispersal ◽

Local Conditions ◽

Spatial Factors ◽

Large Branchiopods

Large branchiopods are threatened worldwide by the loss and degradation of their temporary aquatic habitats owing to drainage and intensive agriculture. Sound ecological knowledge of their diversity and distribution is a prerequisite to formulate effective conservation measures. In the present study, large branchiopods were collected from 82 temporary freshwater pools belonging to five habitat types in Kiskunság (Hungary). Dormant propagule bank analysis complemented the field survey. Eleven species were found, with large branchiopods occurring in more than half of the study systems. The high regional species richness and occurrence frequency of large branchiopods make Kiskunság a true ‘hot spot’ of large branchiopod diversity. The local environment was more important than spatial factors (isolation) in explaining the presence of the most common species. Dispersal was most likely not limiting for the large branchiopods in the study area and colonisation success of different species was differentially affected by local conditions, possibly invertebrate predation risk and hydroperiod. Meadow pools and wheel tracks contributed most to regional species richness through the presence of rare and exclusive species. To conserve branchiopod diversity, we stress the importance of high habitat diversity in the landscape and the need to conserve neglected habitats such as wheel tracks.

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