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Ornamental horticulture is the primary pathway for invasive alien plant introductions. We critically appraise published evidence on the effectiveness of four policy instruments that tackle invasions along the horticulture supply chain: pre-border import restrictions, post-border bans, industry codes of conduct and consumer education., Effective pre-border interventions rely on rigorous risk assessment and high industry compliance. Post-border sales bans become progressively less effective when alien species become widespread in a region., A lack of independent performance evaluation and of public disclosure, limits the uptake and effectiveness of voluntary codes of conduct and discourages shifts in consumer preference away from invasive alien species., Policy implications. Closing the plant invasion pathway associated with ornamental horticulture requires government-industry agreements to fund effective pre- and post-border weed risk assessments that can be subsequently supported by widely adopted, as well as verifiable, industry codes of conduct. This will ensure producers and consumers make informed choices in the face of better targeted public education addressing plant invasions. [ABSTRACT FROM AUTHOR]

To reduce the negative impacts of invasive plants, management interventions such as control or eradication are usually necessary. It is often assumed that the impacts of invasive plants will diminish immediately after such interventions. However, in some cases the invader can have legacy effects in the soil that might persist for long periods, preventing the natural restoration of the areas managed. Therefore, to achieve the re-establishment of a functional native ecosystem it is important to understand for how long such legacies can persist in the soil. This paper explores this issue, using Acacia saligna in South Africa as case study. We collected soil samples in invaded, non-invaded and previously invaded sites (representing 2, 6 and 10 years after clearing) and analysed the levels of pH, carbon, nitrogen, available phosphorus, ammonium, nitrate and electrical conductivity. We also analysed enzyme activities (β-1,4-glucosidase, urease and acid phosphatase). Acacia saligna invasion alters overall soil characteristics but specifically raises pH by 0.6-1.8. Moreover, soil characteristics (e.g. pH) are not restored to natural conditions after control (soil legacy effects persist up to 10 years after clearing). Furthermore, A. saligna control elevates soil [ABSTRACT FROM AUTHOR]

It has been suggested that existing frameworks for guiding management of invasive species in rural areas and protected areas are inadequate for dealing with invasions in urban settings. A framework for selecting appropriate goals for managing invasive species in urban areas was developed by Gaertner et al. (Landsc Urban Plan 151:1-9, 2016). This framework groups species into three management approaches (control priority, active engagement, and tolerance) depending on their real or perceived benefits and their potential to generate negative impacts. This study tests the practical application of the framework using the example of Cape Town. We assess the suitability of the framework to support decision-making for managing invasive species in urban ecosystems using a questionnaire-based survey of members of the public, and an e-mail-based survey and a workshop with invasion biology researchers and managers. Specifically, we (1) determine the differences in perceptions regarding the benefits and impacts of invasive species between the public, managers and researchers; (2) investigate how consistently managers and researchers group invasive species into the three management categories; and (3) identify, with the help of managers and researchers, issues linked to the framework and give suggestions to overcome the identified issues. We found no clear pattern in the perceptions of the public, managers and researchers regarding perceived benefits and negative impacts of invasive species. Instead, the answers were widely scattered among all groups for most of the species that were considered. However, using the framework leads to a higher consistency among managers in placing the species into management categories, compared to invasive species grouping without guidance of the framework. We conclude that decision-support frameworks can assist managers in placing invasive species into management categories. However, even more specific guidelines on the use of invasive species management frameworks in urban areas are needed. [ABSTRACT FROM AUTHOR]

Management of invasive species often raises substantial conflicts of interest. Since such conflicts can hamper proposed management actions, managers, decision makers and researchers increasingly recognize the need to consider the social dimensions of invasive species management. In this exploratory study, we aimed (1) to explore whether species' taxonomic position (i.e. animals vs. plants) and type of invaded landscape (i.e. urban vs. non-urban) might influence public perception about the management of invasive species, and (2) to assess the potential of public awareness to increase public support for invasive species management. We reviewed the scientific literature on the conflicts of interest around the management of alien species and administered two-phased questionnaires (before and after providing information on the target species and its management) to members of the public in South Africa and the UK (n = 240). Our review suggests that lack of public support for the management of invasive animals in both urban and non-urban areas derives mainly from moralistic value disagreements, while the management of invasive plants in non-urban areas mostly causes conflicts based on utilitarian value disagreements. Despite these general trends, conflicts are context dependent and can originate from a wide variety of different views. Notably, informing the public about the invasive status and negative impacts of the species targeted for management appeared to increase public support for the management actions. Therefore, our results align with the view that increased public awareness might increase the public support for the management of invasive species, independent of taxonomic position and type of landscape. [ABSTRACT FROM AUTHOR]

Coastal dune areas are valuable ecosystems, generally impacted by habitat destruction and invasive alien species. In this study, we assessed how human disturbance and invasion by Carpobrotus edulis impact the soils and the establishment of native flora in the north-western coastal regions of Spain. We compared soil characteristics (pH, conductivity, water content, nutrients and enzymatic activities) and native plant as well as C. edulis fitness correlates (germination and early growth) between uninvaded and invaded soils from urban and natural coastal dune areas. We found that human disturbance impacts coastal soils by increasing organic matter and water content, modifying soil nutrients and cycles, and reducing the pH in urban soils. The presence of invasive C. edulis further increases these impacts. These changes in soil characteristics allow for the establishment of the native, but ruderal, Scolymus hispanicus and non-native C. edulis, both of which are not adapted to the typically limiting conditions of coastal dunes. In some instances, the coastal dune endemic, Malcolmia littorea, showed no fitness effects in response to urbanization or the presence of C. edulis. These results suggest that human disturbed coastal areas might be more easily invaded than natural areas. More broadly, our findings of differential responses of different native species to disturbance and invasion, illustrate the need for multi-taxon approaches when assessing the impacts of invasive species. [ABSTRACT FROM AUTHOR]

Ornamental horticulture has been identified as an important threat to plant biodiversity and is a major pathway for plant invasions worldwide. In this context, the family Cactaceae is particularly challenging because it is considered the fifth most threatened large taxonomic group in the world; several species are among the most widespread and damaging invasive species; and Cactaceae is one of the most popular horticultural plant groups. Based on the Convention on International Trade in Endangered Species of Wild Flora and Fauna and the 11 largest online auction sites selling cacti, we documented the international cactus trade. To provide an in-depth look at the dynamics of the industry, we surveyed the businesses involved in the cactus trade in South Africa (a hotspot of cactus trade and invasions). We purchased seeds of every available species and used DNA barcoding to identify species to the genus level. Although <20% of this trade involved threatened species and <3% involved known invasive species, many species were identified by a common name. However, only 0.02% of the globally traded cacti were collected from wild populations. Despite a large commercial network, all South African imports (of which 15% and 1.5% were of species listed as threatened and invasive, respectively) came from the same source. With DNA barcoding, we identified 24% of the species to genus level. Based on our results, we believe that if trade restrictions are placed on the small proportion of cacti that are invasive and there is no major increase in harvesting of native populations, then the commercial trade in cactus poses a negligible environmental threat. However, there are currently no effective methods for easily identifying which cacti are traded, and both the illicit harvesting of cacti from the wild and the informal trade in invasive taxa pose on-going conservation challenges. [ABSTRACT FROM AUTHOR]

A large body of literature shows the link between inadequate housing conditions and poor physical and mental health. The aim of this paper is to summarize the research on the impact of local housing policies on health inequalities, focusing on the issues of access to housing and fuel poverty as studied in the SOPHIE project. Our case studies in Spain showed that people facing housing insecurity, experienced intense levels of mental distress. We found that access to secure and adequate housing can improve the health of these populations, therefore, public policies that address housing instability and their consequences are urgently needed. Housing conditions related to fuel poverty are associated with poorer health and are unevenly distributed across Europe. We found possible positive effects of façade insulation interventions on cold-related mortality in women living in social housing; but not in men. Policies on housing energy efficiency can reduce the health consequences of fuel poverty, but need to be free to users, target the most vulnerable groups and be adaptable to their needs. [ABSTRACT FROM AUTHOR]

The objective of this study is to compare changes in health among a sample of families living in substandard dwellings or with housing affordability problems assisted by Caritas Diocesana de Barcelona, according to the improvement of their socioeconomic and housing situation during the study period. A quasi-experimental study was performed, including 232 families assisted by Caritas who were interviewed in 2012 and one year later. Participants could have received a set of interventions, including relocation and different types of economic subsidies. Regression models were fitted to identify the association of participants' changes in self-rated general health and mental health between baseline and follow-up with improvements across three dimensions: socio-economic situation and housing affordability, physical housing characteristics, and neighborhood. An improvement in self-reported health status was associated with having found a job and reporting fewer problems in meeting monthly housing costs. Mental health improved among participants with an increased household income, with a reduction in the perceived risk of losing their house, and with reduced housing-related material deprivations. The study shows that health gains can derive from improvements in housing conditions, especially those related to housing affordability. [ABSTRACT FROM AUTHOR]

The regulation and management of alien species can be contentious, particularly when the stakeholders who benefit from alien species are different from those who suffer the costs. We propose a consultative process involving relevant stakeholders in invasive species management decisions. The process involves (1) the identification of relevant stakeholders, (2) assessing their perceptions, (3) enhancing interaction between stakeholders, (4) assessing changes in stakeholders' perceptions following interactions with other stakeholders, and (5) developing management recommendations in collaboration with stakeholders. We demonstrate the application of the process using the family Cactaceae ('cacti') in South Africa. Many species of cacti have been introduced to the country over the past two centuries, mostly for horticulture, food and fodder, and hundreds of other species have been introduced in the past few decades (or are likely to be introduced soon) for horticulture. Using the proposed process enabled the negotiation and participation of all stakeholders in decision making and helped minimize contentious situations by clarifying stakeholder's beliefs and exploring consensus solutions. Consequently, management objectives were broadly supported by all stakeholders. These results will be included in a national cactus management strategy for South Africa. [ABSTRACT FROM AUTHOR]