The social dimensions of invasive plants

Attenuated total reflection Fourier-transform infrared spectroscopy reveals environment specific phenotypes in clonal Japanese knotweed

BACKGROUND

Japanese knotweed (Reynoutria japonica var. japonica), a problematic invasive species, has a wide geographical distribution. We have previously shown the potential for attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and chemometrics to segregate regional differentiation between Japanese knotweed plants. However, the contribution of environment to spectral differences remains unclear. Herein, the response of Japanese knotweed to varied environmental habitats has been studied. Eight unique growth environments were created by manipulation of the red: far-red light ratio (R: FR), water availability, nitrogen, and micronutrients. Their impacts on plant growth, photosynthetic parameters, and ATR-FTIR spectral profiles, were explored using chemometric techniques, including principal component analysis (PCA), linear discriminant analysis, support vector machines (SVM) and partial least squares regression. Key wavenumbers responsible for spectral differences were identified with PCA loadings, and molecular biomarkers were assigned. Partial least squared regression (PLSR) of spectral absorbance and root water potential (RWP) data was used to create a predictive model for RWP.

RESULTS

Spectra from plants grown in different environments were differentiated using ATR-FTIR spectroscopy coupled with SVM. Biomarkers highlighted through PCA loadings corresponded to several molecules, most commonly cell wall carbohydrates, suggesting that these wavenumbers could be consistent indicators of plant stress across species. R: FR most affected the ATR-FTIR spectra of intact dried leaf material. PLSR prediction of root water potential achieved an R2 of 0.8, supporting the potential use of ATR-FTIR spectrometers as sensors for prediction of plant physiological parameters.

CONCLUSIONS

Japanese knotweed exhibits environmentally induced phenotypes, indicated by measurable differences in their ATR-FTIR spectra. This high environmental plasticity reflected by key biomolecular changes may contribute to its success as an invasive species. Light quality (R: FR) appears critical in defining the growth and spectral response to environment. Cross-species conservation of biomarkers suggest that they could function as indicators of plant-environment interactions including abiotic stress responses and plant health.

Science for social licence to arrest an ecosystem-transforming invasion

The primary role for scientific information in addressing complex environmental problems, such as biological invasions, is generally assumed to be as a guide for management decisions. However, scientific information often plays a minor role in decision-making, with practitioners instead relying on professional experience and local knowledge. We explore alternative pathways by which scientific information could help reduce the spread and impacts of invasive species. Our study centred on attempts to understand the main motivations and constraints of three local governance bodies responsible for the management of invasive (wilding) conifer species in the southern South Island of New Zealand in achieving strategic and operational goals. We used a combination of workshop discussions, questionnaire responses and visits to field sites to elicit feedback from study participants. We applied a mixed inductive-deductive thematic analysis approach to derive themes from the feedback received. The three main themes identified were: (1) impacts of wilding conifers and goals for wilding conifer control, (2) barriers to achieving medium- and long-term goals, and (3) science needed to support wilding conifer control. Participants identified reversal and prevention of both instrumental (e.g. reduced water availability for agriculture) and intrinsic (e.g. loss of biodiversity and landscape values) impacts of wilding conifer invasions as primary motivators behind wilding conifer control. Barriers to achieving goals were overwhelmingly social, relating either to unwillingness of landowners to participate or poorly designed regulatory frameworks. Consequently, science needs related primarily to gaining social licence to remove wilding conifers from private land and for more appropriate regulations. Scientific information provided via spread and impacts forecasting models was viewed as a key source of scientific information in gaining social licence. International experience suggests that invasive species control programmes often face significant external social barriers. Thus, for many biological invasions, the primary role of science might be to achieve social licence and regulatory support for the long-term goals of invasive species control programmes and the management interventions required to achieve those goals.

Scaling up qualitative research to harness the capacity of lay people in invasive plant management

Successful management of invasive plants (IPs) requires the active participation of diverse communities across land tenures. This can be challenging because communities do not always share the views of scientists and managers. They may directly disagree, have alternative views, or be unwilling to manage IPs. Reviews of IP social science identify opportunities to better understand the role of cultural processes and everyday practices to address these challenges. To scale up and leverage the insights of existing qualitative social science IP research, we used meta-ethnography to unlock accounts and interpretations of lay perspectives. Meta-ethnography is a form of qualitative research synthesis increasingly used beyond its origins in health and education to produce interpretive syntheses of an area of research. In the 7 phases of meta-ethnography, we systematically identified and synthesized 19 qualitative articles pertinent to lay experience and knowledge of IPs in diverse settings. Action and meaning regarding IPs were influenced by 6 meta-themes in personal and social life: dissonance, priorities, difference, agency, responsibility, and future orientations. Through descriptions and examples of each meta-theme, we demonstrated how the meta-themes are higher level structuring concepts across the qualitative research that we analyzed and we retained grounding in the in-depth qualitative research. We characterized the meta-themes as leverage points and tensions by which we reframed lay people in terms of capacity for reflective IP management rather than as obstacles. The meta-ethnography synthesis shows how leverage points and tensions emerge from everyday life and can frame alternative and meaningful starting points for both research and public engagement and deliberation regarding IP management. These insights are not a panacea, but open up new space for reflective and mutual consideration of how to effectively navigate often complex IP problems and address conservation and social and livelihood issues in dynamic social and physical environments.

Distribution and management of Fallopia japonica in riparian biotopes in Slovakia and Austria

Globally, invasive species represent a serious threat to biodiversity and to the ecosystem. As an undesirable part of riparian ecosystems, invasive plants form continuous growths on the banks of watercourses. One of the biggest problems at river bank sites is Japanese knotweed, Fallopia japonica (Houtt.) Ronse Decr, which is an extremely invasive and aggressive weed. The topic of the interaction of flow and invasive plant species in shore stands is rich and presents a wide range of possibilities for research. The presented paper brings the results of our studies on the invasions of F. japonica in chosen riparian vegetation sites in Austria and Slovakia from 2011–2020 (36 stands). Our research was aimed at the survey on the changes in the distribution (spread) of F. japonica at the selected river sites; assessment of the impact of the watercourse regime on the spread of F. japonica; monitoring of the population growth dynamics of F. japonica and assessment of possibilities for effective eradication of F. japonica in context of the riparian vegetation management. We used standard techniques of field survey, mapping, flow modeling/simulation, and laboratory experiments. Our research results showed that water streams are not primary invasion starters until there is a flood. As long as flooding does not exceed the critical speed of the water stream, there is no direct damage to the invasive plant. The water body can be a secondary trigger for plant invasion at normal speeds. In addition, F. japonica reproduction ability directly conditions its population dynamic growth. We can report that selective invasion removal adapted to local conditions can be most suitable and beneficial for municipalities.

Social science for conservation in working landscapes and seascapes

Biodiversity is in precipitous decline globally across both terrestrial and marine environments. Therefore, conservation actions are needed everywhere on Earth, including in the biodiversity rich landscapes and seascapes where people live and work that cover much of the planet. Integrative landscape and seascape approaches to conservation fill this niche. Making evidence-informed conservation decisions within these populated and working landscapes and seascapes requires an in-depth and nuanced understanding of the human dimensions through application of the conservation social sciences. Yet, there has been no comprehensive exploration of potential conservation social science contributions to working landscape and seascape initiatives. We use the Smithsonian Working Land and Seascapes initiative – an established program with a network of 14 sites around the world – as a case study to examine what human dimensions topics are key to improving our understanding and how this knowledge can inform conservation in working landscapes and seascapes. This exploratory study identifies 38 topics and linked questions related to how insights from place-based and problem-focused social science might inform the planning, doing, and learning phases of conservation decision-making and adaptive management. Results also show how conservation social science might yield synthetic and theoretical insights that are more broadly applicable. We contend that incorporating insights regarding the human dimensions into integrated conservation initiatives across working landscapes and seascapes will produce more effective, equitable, appropriate and robust conservation actions. Thus, we encourage governments and organizations working on conservation initiatives in working landscapes and seascapes to increase engagement with and funding of conservation social science.

Be(e)coming pollinators: Beekeeping and perceptions of environmentalism in Massachusetts

In an era of mass extinction and biodiversity crisis, it is increasingly crucial to cultivate more just and inclusive multispecies futures. As mitigation and adaption efforts are formed in response to these crises, just transitions forward require intentional consideration of the hybrid entanglement of humans, human societies, and wider landscapes. We thus apply a critical hybridity framework to examine the entanglement of the pollinator crisis with the cultural and agricultural practice of hobbyist beekeeping. We draw on ethnographic engagements with Massachusetts beekeepers and find apiculture to be widely understood as a form of environmentalism-including as both a mitigation to and adaptation for the pollinator crisis. Illustrating how power-laden socioecological negotiations shape and reshape regional environments, we then discuss how this narrative relies on the capitalistic and instrumental logics characteristic of Capitalocene environmentalisms. These rationalities, which obscure the hybridity of landscapes, consequently increase the likelihood of problematic unintended consequences. Also present, however, is a deeper engagement with hybrid perspectives, with some beekeepers even offering pathways toward inclusive solutions. We conclude that if more just and biodiverse futures are to be realized, beekeeping communities must foster increasingly hybrid visions of apiculture as situated within socioecological and contested landscapes.

Educational Approaches Help Bridge Perception Gaps of Invasive Alien Species (Mikania micrantha) between Managers and Non-managers

Invasive alien species (IAS) significantly impact biodiversity, human health, and economies, and considerable resources are often used to manage their spread. Few studies have focused on the human perception of IAS management, and little is known about approaches to improve stakeholder perception. This study examined perception gaps between managers and non-managers of a notorious weed Mikania micrantha and the preference for educational approaches to bridge those gaps. Household questionnaires and key informant interviews were conducted in the China-Myanmar Border Region (China), and ordinal logistic regressions and Wilcoxon rank sum tests were used in statistical analyses. We found a high level of perception of M. micrantha among stakeholders, and a significant influence of socio-demographic factors including gender, educational level, ethnic group, and geographical location. Scores of the identification, damage, control measure, and manual treatment of M. micrantha were significantly higher for managers than those for non-managers, indicating that there were certain perception gaps between two stakeholder groups. Nine educational approaches were identified as being effective in improving stakeholder perception of IAS, of which training workshops were mostly preferred, followed by brochures (or leaflets) and other promotional materials. Additionally, we propose that well-designed and well-conducted educational approaches would benefit stakeholder perception of IAS, and that integration of IAS management into a comprehensive rural development scheme would improve its long-term performance in marginalized rural communities.

Factors Influencing Family Forest Owners' Interest in Community-led Collective Invasive Plant Management

Effective invasive plant management requires collective action. However, little is known about what motivates individuals to work collectively. We conducted a mail survey of 2,600 randomly selected family forest owners in Indiana, USA to examine factors associated with community-led collective action. Specifically, we examined the role of perceived self-efficacy, perceived collective efficacy, concerns about invasive plants, and social norms associated with invasive plant management in shaping family forest owners' self-reported likelihood to work with their neighbors to remove invasive plants. We found that past experience talking to others or working with neighbors to remove invasive plants were important predictors of landowners' intention to work collectively, as were perceived self-efficacy in their own ability to manage invasive plants, perceived need for collective action, social norms, and concerns about invasive plants on neighboring or nearby properties. However, most socio-demographic characteristics (e.g., age, gender, education level, income) and land ownership characteristics (e.g., residence status, having a written forest management plan) were not statisically significant predictors of family forest owners' likelihood to work with their neighbors. Our findings suggest that building individual sense of competence, facilitating neighbor interactions, and strengthening shared concerns may facilitate community-led collective action to manage invasive plants.

Understanding invasive plant management on family forestlands: An application of protection motivation theory

Invasive forest plants are a growing concern because of their perceived and actual negative ecological, economic, and social impacts. To effectively manage invasive plants in forest ecosystems, it is paramount to understand the management decisions made by family forest owners (FFOs), who collectively own 36% of forestlands in the United States. We contribute to the growing literature on invasive plant management and the factors that influence FFOs' likelihood to manage invasive plants on their property by incorporating protection motivation theory (PMT; Rogers 1975). Protection Motivation Theory argues that the degree to which individuals protect themselves from a perceived threat varies as a function of the perceived severity of the threat, their vulnerability to the threat, their perceptions of self-efficacy to effectively mitigate the threat, and the degree to which they believe they have access to the resources needed to effectively respond to the threat. We surveyed a random sample of 2,600 FFOs in Indiana about their knowledge, perceptions, experience, and plans regarding invasive plants on their wooded lands. Consistent with PMT, we constructed a hierarchical binary logistic model and found that FFOs reported greater intentions to manage invasive plants when they perceived the problem to be more severe and also when they felt a stronger sense of self-efficacy to address the problem. Although perceived vulnerability was not significant in our final model, our results also show that FFOs who had previous invasive plant management experience, had a Bachelor's degree or higher level of education, owned woodlands for recreational purposes, and were more subject to normative social influence also tended to report greater intentions to manage invasive plants. Together, these results suggest that components of PMT (perceived severity and self-efficacy) may be used to inform potential strategies, programs, and outreach for engaging family forest owners in invasive plant management.

Distribution of Asian knotweeds on the Rhône River basin, France: A multi-scale model of invasibility that combines biophysical and anthropogenic factors

Biotic and abiotic factors are important drivers of the introduction, dispersal and establishment of an invasive species in fluvial corridors. In this study, we propose to better understand the spatial distribution of Asian knotweeds and to model their invasibility at the river basin scale in the Rhône Mediterranean and Corsica regions, France. We implemented a multiscale analysis of biophysical and anthropogenic factors related to the presence of knotweeds. Subbasins were sampled (50-600 km²), a large dataset on knotweed occurrence and biotic/abiotic factors was collected, and logistic regression was applied. A robust logit model (accuracy: 90%; false positive rate: 13%) estimated the probability of the occurrence of knotweeds at the river basin scale. We found clear evidence of: i) spatial scale-dependent water availability for knotweed implantation (e.g., summer vs. winter rainfalls > 250 mm); ii) an important role of hydrogeomorphic forces in dispersal; and iii) interspecific competition in riparian areas. The occurrence of knotweeds is also closely related to human-derived pressures. The management of knotweeds on roads and railways in the vicinity of rivers may be a major source of propagules. Hydraulic infrastructures (dikes and mill weirs) may also have served as locations of knotweed introduction since the end of the nineteenth century and may play a major role in the propagule transfer of knotweed; to date, these infrastructures have provided favourable conditions for knotweed establishment. Despite local water authorities' increasing awareness of invasive plants, local management practices for flood mitigation, low awareness of roads/railway managers, and negative representations of knotweeds have probably largely contributed to their dispersion over decades. The final model intends to integrate these biophysical and human factors by providing an operational tool to help river managers determine the sensitivity of their river basins to knotweed invasion.

Pathogen Incursions - Integrating Technical Expertise in a Socio-Political Context

The incursion of a plant pathogen into a new geographic area initiates a series of decisions about appropriate control or eradication efforts. Incomplete, erroneous, and/or selective information may be used by diverse stakeholders to support individual goals and positions on how an incursion should be managed. We discuss the complex social, political, and technical factors that shape a biosecurity response prior to reviewing information needs and common stakeholder misunderstandings. Selected examples focus on the rust fungi (order Pucciniales). We then explore how plant pathologists, as technical experts, can interact with biosecurity stakeholders to build empathy and understanding that in turn allows a shift from being a distant subject matter expert to an active participant helping to structure problems and shape knowledge flows for better outcomes.

Exploring farmers' behavior toward individual and collective measures of Western Corn Rootworm control - A case study in south-east Austria

Invasive species are considered a major threat for global agricultural production, biodiversity and ecosystem services. Their spread and establishment is mainly influenced by bio-physical factors, but also by people's activities such as tourism or farming. Understanding farmers' behavior is necessary to develop effective control measures. We conducted qualitative semi-structured interviews in south-east Austria to explore factors that facilitate or impede farmers' behavior to individually or collectively control the invasive Western Corn Rootworm (WCR, Diabrotica virgifera virgifera). We analyze the interview contents using the Capability-Opportunity-Motivation-Behavior model (COM-B model). Our results show that farmers' motivation and related behavior is influenced by intra- and interpersonal factors such as their knowledge about WCR control measures (capability psychological), perceived societal acceptance of WCR control measures or perceived normative obligations to participate in collective measures (opportunity social). Farmers' motivation (reflective and automatic) for implementing individual or collective WCR control measures is mainly determined by their perceived self-efficacy, their perceived efficacy of WCR control measures and the perceived severity of WCR damages. Contextual factors such as environmental conditions, legal regulations, the landscape composition, the farm type or financial impacts of WCR control measures (opportunity physical) are essential prerequisites for farmers' behavior. The results suggest that new modes of knowledge transfer are required to facilitate the proactive implementation of individual and collective WCR control measures prior to trigger events, such as severe WCR damages. The development of a trusting and communicative environment between farmers is key for collective WCR control. Exchange with residents about WCR and applied control measures may help to create a shared understanding and increase societal acceptance. Moreover, a long-term and proactive coordination which meets individual famers' needs is required to implement collective WCR control measures. Farmers who have successfully implemented individual and collective WCR measures may encourage non-applicants and sceptics by "learning from peers".

Fact and value in invasion biology

Some invasion biologists contend their science has reached a consensus on 4 facts: cost estimates of the effects of nonindigenous species provided in papers by Pimentel et al. are credible; invasive species generally, not just predators, pose significant extinction threats; characteristic biological differences distinguish novel from native species, ecosystems, communities, and processes; and ontological dualism, which distinguishes between natural and anthropogenic processes and influences, plays a useful role in biological inquiry. I contend there is no convincing empirical evidence for any of these propositions. Leading invasion biologists cite their agreement about these propositions as evidence for them and impugn the motives of critics who believe consensus should be based on evidence not the other way around.

Explaining people's perceptions of invasive alien species: A conceptual framework

Human perceptions of nature and the environment are increasingly being recognised as important for environmental management and conservation. Understanding people's perceptions is crucial for understanding behaviour and developing effective management strategies to maintain, preserve and improve biodiversity, ecosystem services and human well-being. As an interdisciplinary team, we produced a synthesis of the key factors that influence people's perceptions of invasive alien species, and ordered them in a conceptual framework. In a context of considerable complexity and variation across time and space, we identified six broad-scale dimensions: (1) attributes of the individual perceiving the invasive alien species; (2) characteristics of the invasive alien species itself; (3) effects of the invasion (including negative and positive impacts, i.e. benefits and costs); (4) socio-cultural context; (5) landscape context; and (6) institutional and policy context. A number of underlying and facilitating aspects for each of these six overarching dimensions are also identified and discussed. Synthesising and understanding the main factors that influence people's perceptions is useful to guide future research, to facilitate dialogue and negotiation between actors, and to aid management and policy formulation and governance of invasive alien species. This can help to circumvent and mitigate conflicts, support prioritisation plans, improve stakeholder engagement platforms, and implement control measures.

Do people care about pine invasions? Visitor perceptions and willingness to pay for pine control in a protected area

Tree invasions are increasing globally, causing major problems for biodiversity, ecosystem services and human well-being. In South America, conifer invasions occur across many ecosystems and while numerous studies address the ecological consequences of these invasions, little is known about social perceptions and people's attitudes toward their control. The social perceptions on the effect of invasive conifers can include recreational, cultural and conservation dimensions. This study, conducted in the Malalcahuello National Reserve, aims to assess visitor's perception about invasive pines (Pinus spp.) and their effects on the endangered Araucaria araucana forests and determine their willingness to pay for pine control. We used a questionnaire to survey visitors to the reserve in both winter and summer (n = 138 for each season). When confronted with six images of araucaria and pine forests with and without snow, visitors consistently preferred landscapes without pines and disliked those completely dominated by pines the most. Almost half, 46.5%, of the visitors expressed their willingness to pay (WTP) for pine control and after given a brief explanation about pine impacts, this number rose to 79%. Visitors who said they were unwilling to pay argue ethical, aesthetic and pragmatic considerations relating closely to a number of social value systems and beliefs. Our study shows that there is a high variation in how people assess the threat of invasive pine species in natural areas, but education even in a very brief format can help to increase awareness of the problem and build social and financial support for its control.

The human and social dimensions of invasion science and management

Biological invasions are a leading cause of global environmental change given their effects on both humans and biodiversity. Humans introduce invasive alien species and may facilitate their establishment and spread, which can alter ecosystem services, livelihoods, and human well-being. People perceive the benefits and costs of these species through the lens of diverse value systems; these perspectives influence decisions about when and where to manage them. Despite the entanglement of humans with invasive alien species, most research on the topic has focused on their ecological aspects. Only relatively recently have the human and social dimensions of invasions started to receive sustained attention in light of their importance for understanding and governing biological invasions. This editorial draws on contributions to a special issue on the "Human and Social Dimensions of Invasion Science" and other literature to elucidate major trends and current contributions in this research area. We examine the relation between humans and biological invasions in terms of four crosscutting themes: (1) how people cause biological invasions; (2) how people conceptualise and perceive them; (3) how people are affected - both positively and negatively - by them; and (4) how people respond to them. We also highlight several ways in which research on the human and social dimensions of invasion science improves understanding, stakeholder engagement, and management.

Weed hygiene practices in rural industries and public land management: Variable knowledge, patchy implementation, inconsistent coordination

Weed management science and practice largely focuses on eradicating, containing and reducing existing weed populations; the focus is on plants in situ. More recently, the redefinition of biosecurity to include weeds has seen greater attention paid to preventing the introduction of weeds to previously uninfested areas within countries. Thus weed hygiene has come to the fore, with a growing number of publications recommending a diverse range of practices to minimise the spread of weeds across farm, regional and state boundaries. Yet little is known about the uptake of weed hygiene practices. The aim of this paper is to evaluate the extent to which best practice weed hygiene is being implemented on, across and along private and public lands. Telephone interviews were conducted with 54 private and public land managers, weed contractors, and agricultural transport operators in New South Wales, Australia. Vehicle hygiene was commonly undertaken across all stakeholder groups when it was consistent with other goals, requirements or norms. Other practices, such as sequencing harvesting from least to most weedy paddocks or including weed hygiene clauses in contracts were often known, but rarely practiced because of the onerous labour and financial costs or concerns about social etiquette. Individual commitment to weed hygiene efforts were also undermined by intra and inter-organisational coordination challenges. Public debate and assessment are needed on the benefits and costs to society of weed hygiene compared to in situ weed control to determine where best to invest limited time and resources.