Search results for "introduced species"
showing 10 items of 147 documents
Phycological Herbaria as a Useful Tool to Monitor Long-Term Changes of Macroalgae Diversity: Some Case Studies from the Mediterranean Sea
2020
The Mediterranean Sea is currently experiencing a decline in the abundance of several key species, as a consequence of anthropogenic pressures (e.g., increase in human population, habitat modification and loss, pollution, coastal urbanization, overexploitation, introduction of non-indigenous species and climate change). Herbaria and natural history collections are certainly fundamental for taxonomic studies, but they are also an invaluable, if currently underestimated, resource for understanding ecological and evolutionary responses of species to environmental changes. Macroalgae herbarium collections, which are really consistent (ranging from 200,000 to approximately 500,000 specimens) in …
Native egg parasitoids recorded from the invasive Halyomorpha halys successfully exploit volatiles emitted by the plant–herbivore complex
2017
When an accidentally introduced pest establishes in the invaded area, native natural enemies may adapt to the new host. A decade after the accidental introduction of the brown marmorated stink bug, Halyomorpha halys, in Europe, two generalist native egg parasitoids, the eupelmid Anastatus bifasciatus and the encyrtid Ooencyrtus telenomicida, have been recorded from this invasive agricultural pest in the field. Both species are able to complete development to the adult stage within the new host. Trissolcus basalis (Platygastridae = Scelionidae), which is not associated with H. halys in the field, was reared from freeze-killed sentinel eggs placed on soybean plants in central Italy. We tested…
The alien vascular flora of Linosa (Pelagie Islands, Strait of Sicily): update and management proposals
2017
This paper provides an up-to-date overview of the naturalized alien plants of Linosa (Pelagie Archipelago, Sicily), which includes 83 taxa and accounts for 29 % of the total island's flora. Among these plants, 6 are invasive, 49 are naturalized and 28 are casual. With respect to previous available data, our field investigations resulted in the addition of 31 new xenophytes (21 casual and 10 fully naturalized). One of these species is new to the whole European territory (Kleinia anteuphorbia), 6 of them are new to Sicily and 11 are recorded for the first time on circum-Sicilian islets. For each alien plant, we indicate the habitat where the naturalization has been observed by using the codes…
Assessing environmental conditions of Antarctic footpaths to support management decisions.
2016
Thousands of tourists visit certain Antarctic sites each year, generating a wide variety of environmental impacts. Scientific knowledge of human activities and their impacts can help in the effective design of management measures and impact mitigation. We present a case study from Barrientos Island in which a management measure was originally put in place with the goal of minimizing environmental impacts but resulted in new undesired impacts. Two alternative footpaths used by tourist groups were compared. Both affected extensive moss carpets that cover the middle part of the island and that are very vulnerable to trampling. The first path has been used by tourists and scientists since over …
Effects of changing climate on European stream invertebrate communities : A long-term data analysis
2018
Long-term observations on riverine benthic invertebrate communities enable assessments of the potential impacts of global change on stream ecosystems. Besides increasing average temperatures, many studies predict greater temperature extremes and intense precipitation events as a consequence of climate change. In this study we examined long-term observation data (10-32years) of 26 streams and rivers from four ecoregions in the European Long-Term Ecological Research (LTER) network, to investigate invertebrate community responses to changing climatic conditions. We used functional trait and multi-taxonomic analyses and combined examinations of general long-term changes in communities with deta…
Degradation of sexual reproduction in Veronica filiformis after introduction to Europe
2011
Abstract Background Baker’s law predicts that self-incompatible plant species are generally poor colonizers because their mating system requires a high diversity of genetically differentiated individuals and thus self-compatibility should develop after long-distance dispersal. However, cases like the introduction of the self-incompatible Veronica filiformis (Plantaginaceae) to Europe constitute an often overlooked alternative to this rule. This species was introduced from subalpine areas of the Pontic-Caucasian Mountains and colonized many parts of Central and Western Europe in the last century, apparently without producing seeds. To investigate the consequences of the absence of sexual rep…
The Lower Danube River-Danube Delta-North West Black Sea: A pivotal area of major interest for the past, present and future of its fish fauna--A shor…
2015
The complex Danube-Black Sea geoecosystem, created by a unique combination of integrated biotopes and biocoenoses related forces and counter-forces in time and space, forms a rich "ichthyosystem". The equilibrium among the fish species captured in the Danube Delta reveals its structural and functional roles in the connectivity of the Danube and Black Sea. The key role of the delta is evidenced by the fact that 57.26% of the Lower Danube-Danube Delta-North West Black Sea fish species use two or three of the subsystems in terms of habitats. Therefore, this convergence area can be considered to be a dynamic and rich "ichthyosystem", with three subsystems. All three evolved interdependently, wh…
Phytotoxic Effects of Commercial Eucalyptus citriodora, Lavandula angustifolia, and Pinus sylvestris Essential Oils on Weeds, Crops, and Invasive Spe…
2019
Background: essential oils are well known for their pharmacological effectiveness as well as their repellent, insecticide, and herbicide activities. The emergence of resistant weeds, due to the overuse of synthetic herbicides, makes it necessary to find natural alternatives for weed control. The aim of this study was to evaluate the phytotoxic effects of Eucalyptus citriodora, Lavandula angustifolia, and Pinus sylvestris, three common commercial essential oils, on weeds (Portulaca oleracea, Lolium multiflorum, and Echinochloa crus-galli), food crops (tomato and cucumber), and the invasive species Nicotiana glauca. Methods: to determine herbicidal effects, essential oils were tested at diffe…
An updated checklist of the vascular flora native to Italy
2018
AbstractAn updated inventory of the vascular flora alien to Italy, providing details on the occurrence at regional level, is presented. The checklist includes 1597 species, subspecies, and hybrids, distributed in 725 genera and 152 families; 2 taxa are lycophytes, 11 ferns and fern allies, 33 gymnosperms, and 1551 angiosperms. 157 taxa are archaeophytes and 1440 neophytes. The alien taxa currently established in Italy are 791 (570 naturalized and 221 invasive), while 705 taxa are casual aliens, 4 are not assessed, 7 are of unknown regional distribution, 47 have not been confirmed in recent times, 3 are considered extinct or possibly extinct in the country, and 40 are doubtfully occurring in…
The genome sequence of the grape phylloxera provides insights into the evolution, adaptation, and invasion routes of an iconic pest
2020
Background: Although native to North America, the invasion of the aphid-like grape phylloxera Daktulosphaira vitifoliae across the globe altered the course of grape cultivation. For the past 150 years, viticulture relied on grafting-resistant North American Vitis species as rootstocks, thereby limiting genetic stocks tolerant to other stressors such as pathogens and climate change. Limited understanding of the insect genetics resulted in successive outbreaks across the globe when rootstocks failed. Here we report the 294-Mb genome of D. vitifoliae as a basic tool to understand host plant manipulation, nutritional endosymbiosis, and enhance global viticulture. Results: Using a combination of…