When faced with a large species pool of invasive or potentially invasive alien plants, prioritizationis an essential prerequisite for focusing limited resources on species which inflicthigh impacts, have a high rate of spread and can be cost-effectively managed. The prioritizationprocess as detailed within this paper is the first tool to assess species for priority forrisk assessment (RA) in the European Union (EU) specifically designed to incorporate therequirements of EU Regulation no. 1143/2014. The prioritization process can be used forany plant species alien to the EU, whether currently present within the territory or absent.The purpose of the prioritization is to act as a preliminarily evaluation to determine whichspecies have the highest priority for RA at the EU level and may eventually be proposedfor inclusion in the list of invasive alien species of EU concern. The preliminary risk assessmentstage (Stage 1), prioritizes species into one of four lists (EU List of Invasive AlienPlants, EU Observation List of Invasive Alien Plants, EU List of Minor Concern and theResidual List) based on their potential for spread coupled with impacts. The impacts onnative species and ecosystem functions and related ecosystem services are emphasized inline with Article 4.3(c) of the Regulation. Only those species included in the EU List ofInvasive Alien Plants proceed to Stage 2 where potential for further spread and establishmentcoupled with evaluating preventative and management actions is evaluated. The outputof Stage 2 is to prioritize those species which have the highest priority for a RA at the EUlevel or should be considered under national measures which may involve a trade ban, cessationof cultivation, monitoring, control, containment or eradication. When consideringalien plant species for the whole of the EPPO region, or for species under the Plant HealthRegulation, the original EPPO prioritization process for invasive alien plants remains theoptimum tool.
The integration of international, national and local regulations is one of the fundamental steps for preventing, controlling and managing biological invasions. The aim of the present study is to present and analyse, for the first time, the list of all non-native plant species that are regulated in Italy by the European, Italian and regional legislation in force. To date, there are 147 regulated non-native plant taxa. This number includes the 36 invasive alien plants of European Union concern and additional 111 taxa (95 species and 16 collective taxa) that have been listed at the regional level alone. A total of 19 plants of European Union concern and 95 regulated plants are present in the wild in at least one administrative region. The majority of the 95 species that are listed at the regional level alone are woody species (23 trees, 9 shrubs, 6 woody vines), followed by 29 herbs (19 annual herbs, 10 perennial herbs) and 11 aquatic plants. By presenting the regulated species and by identifying the most relevant species, the present study will provide an important tool to support plant invasion research and management and for the application of Regulation (EU) no. 1143/2014 on invasive alien species.
The integration of international, national and local regulations is one of the fundamental steps for preventing, controlling and managing biological invasions. The aim of the present study is to present and analyse, for the first time, the list of all non-native plant species that are regulated in Italy by the European, Italian and regional legislation in force. To date, there are 147 non-native plant taxa regulated. This number includes the 36 invasive alien plants of European Union concern and additional 111 taxa (95 species and 16 collective taxa) that have been listed at the regional level alone. A total of 19 plants of European Union concern and 95 regulated plants are present in the wild in at least one administrative region. The majority of the 95 species that are listed at the regional level alone are woody species (23 trees, 9 shrubs, 6 woody vines), followed by 29 herbs (19 annual herbs, 10 perennial herbs) and 11 aquatic plants. By presenting the regulated species and by identifying the most relevant species, the present study will provide an important tool to support plant invasion research and management and for the application of Regulation (EU) no. 1143/2014 on invasive alien species.
The paper provides the first estimate of the composition and structure of alien plants occurring in the wild in the European continent, based on the results of the DAISIE project (2004-2008), funded by the 6th Framework Programme of the European Union and aimed at "creating an inventory of invasive species that threaten European terrestrial, freshwater and marine environments". The plant section of the DAISIE database is based on national checklists from 48 European countries/regions and Israel; for many of them the data were compiled during the project and for some countries DAISIE collected the first comprehensive checklists of alien species, based on primary data (e.g., Cyprus, Greece, R Y. R. O. Macedonia, Slovenia, Ukraine). In total, the database contains records of 5789 alien plant species in Europe (including those native to a part of Europe but alien to another part), of which 2843 are alien to Europe (of extra-European origin). The research focus was on naturalized species; there are in total 3749 naturalized aliens in Europe, of which 1780 are alien to Europe. This represents a marked increase compared to 1568 alien species reported by a previous analysis of data in Flora Europaea (1964-1980). Casual aliens were marginally considered and are represented by 1507 species with European origins and 872 species whose native range falls outside Europe. The highest diversity of alien species is concentrated in industrialized countries with a tradition of good botanical recording or intensive recent research. The highest number of all alien species, regardless of status, is reported from Belgium (1969), the United Kingdom (1779) and Czech Republic (1378). The United Kingdom (857), Germany (450), Belgium (447) and Italy (440) are countries with the most naturalized neophytes. The number of naturalized neophytes in European countries is determined mainly by the interaction of temperature and precipitation; it increases with increasing precipitation but only in climatically warm and moderately warm regions. Of the nowadays naturalized neophytes alien to Europe, 50% arrived after 1899, 25% after 1962 and 10% after 1989. At present, approximately 6.2 new species, that are capable of naturalization, are arriving each year. Most alien species have relatively restricted European distributions; half of all naturalized species occur in four or fewer countries/regions, whereas 70% of non-naturalized species occur in only one region. Alien species are drawn from 213 families, dominated by large global plant families which have a weedy tendency and have undergone major radiations in temperate regions (Asteraceae, Poaceae, Rosaceae, Fabaceae, Brassicaceae). There are 1567 genera, which have alien members in European countries, the commonest being globally-diverse genera comprising mainly urban and agricultural weeds (e.g., Amaranthus, Chenopodium and Solanum ) or cultivated for ornamental purposes (Cotoneaster, the genus richest in alien species). Only a few large genera which have successfully invaded (e.g., Oenothera, Oxalis, Panicum, Helianthus ) are predominantly of non-European origin. Conyza canadensis, Helianthus tuberosus and Robinia pseudoacacia are most widely distributed alien species. Of all naturalized aliens present in Europe, 64.1% occur in industrial habitats and 58.5% on arable land and in parks and gardens. Grasslands and woodlands are also highly invaded, with 37.4 and 31.5%, respectively, of all naturalized aliens in Europe present in these habitats. Mires, bogs and fens are least invaded; only approximately 10% of aliens in Euope occur there. Intentional introductions to Europe (62.8% of the total number of naturalized aliens) prevail over unintentional (37.2%). Ornamental and horticultural introductions escaped from cultivation account for the highest number of species, 52.2% of the total. Among unintentional introductions, contaminants of seed, mineral materials and other commodities are responsible for 1091 alien species introductions to Europe (76.6% of all species introduced unintentionally) and 363 species are assumed to have arrived as stowaways (directly associated with human transport but arriving independently of commodity). Most aliens in Europe have a native range in the same continent (28.6% of all donor region records are from another part of Europe where the plant is native); in terms of species numbers the contribution of Europe as a region of origin is 53.2%. Considering aliens to Europe separately, 45.8% of species have their native distribution in North and South America, 45.9% in Asia, 20.7% in Africa and 5.3% in Australasia. Based on species composition, European alien flora can be classified into five major groups: (1) north-western, comprising Scandinavia and the UK; (2) west-central, extending from Belgium and the Netherlands to Germany and Switzerland; (3) Baltic, including only the former Soviet Baltic states; (4) east-central, comprizing the remainder of central and eastern Europe; (5) southern, covering the entire Mediterranean region. The clustering patterns cut across some European bioclimatic zones; cultural factors such as regional trade links and traditional local preferences for crop, forestry and ornamental species are also important by influencing the introduced species pool. Finally, the paper evaluates a state of the art in the field of plant invasions in Europe, points to research gaps and outlines avenues of further research towards documenting alien plant invasions in Europe. The data are of varying quality and need to be further assessed with respect to the invasion status and residence time of the species included. This concerns especially the naturalized/casual status; so far, this information is available comprehensively for only 19 countries/regions of the 49 considered. Collating an integrated database on the alien flora of Europe can form a principal contribution to developing a European-wide management strategy of alien species.
Sustainably managed non-native trees deliver economic and societal benefits with limited risk of spread to adjoining areas. However, some plantations have launched invasions that cause substantial damage to biodiversity and ecosystem services, while others pose substantial threats of causing such impacts. The challenge is to maximise the benefits of non-native trees, while minimising negative impacts and preserving future benefits and options. A workshop was held in 2019 to develop global guidelines for the sustainable use of non-native trees, using the Council of Europe – Bern Convention Code of Conduct on Invasive Alien Trees as a starting point. The global guidelines consist of eight recommendations: 1) Use native trees, or non-invasive non-native trees, in preference to invasive non-native trees; 2) Be aware of and comply with international, national, and regional regulations concerning non-native trees; 3) Be aware of the risk of invasion and consider global change trends; 4) Design and adopt tailored practices for plantation site selection and silvicultural management; 5) Promote and implement early detection and rapid response programmes; 6) Design and adopt tailored practices for invasive non-native tree control, habitat restoration, and for dealing with highly modified ecosystems; 7) Engage with stakeholders on the risks posed by invasive non-native trees, the impacts caused, and the options for management; and 8) Develop and support global networks, collaborative research, and information sharing on native and non-native trees. The global guidelines are a first step towards building global consensus on the precautions that should be taken when introducing and planting non-native trees. They are voluntary and are intended to complement statutory requirements under international and national legislation. The application of the global guidelines and the achievement of their goals will help to conserve forest biodiversity, ensure sustainable forestry, and contribute to the achievement of several ...
Invasive alien plants are a major threat to biodiversity and they contribute to the unfavourable conservation status of habitats of interest to the European Community. In order to favour implementation of European Union Regulation no. 1143/2014 on invasive alien species, the Italian Society of Vegetation Science carried out a large survey led by a task force of 49 contributors with expertise in vegetation across all the Italian administrative regions. The survey summed up the knowledge on impact mechanisms of invasive alien plants in Italy and their outcomes on plant communities and the EU habitats of Community Interest, in accordance with Directive no. 92/43/EEC. The survey covered 241 alien plant species reported as having deleterious ecological impacts. The data collected illustrate the current state of the art, highlight the main gaps in knowledge, and suggest topics to be further investigated. In particular, the survey underlined competition as being the main mechanism of ecological impact on plant communities and Natura 2000 habitats. Of the 241 species, only Ailanthus altissima was found to exert an ecological impact on plant communities and Natura 2000 habitats in all Italian regions; while a further 20 species impact up to ten out of the 20 Italian administrative regions. Our data indicate that 84 out of 132 Natura 2000 Habitats (64%) are subjected to some degree of impact by invasive alien plants. Freshwater habitats and natural and semi-natural grassland formations were impacted by the highest number of alien species, followed by coastal sand dunes and inland dunes, and forests. Although not exhaustive, this research is the first example of nationwide evaluation of the ecological impacts of invasive alien plants on plant communities and Natura 2000 Habitats.
