Dr. Ross Taylor Shackleton

Allelochemical production is a plausible mechanism promoting the invasion of Prosopis species in their introduced ranges. This study assessed how allelopathy affects the nodulation and growth of non-native Prosopis species (P. juliflora and P. pallida) and native P. cineraria congeners in the United Arab Emirates (UAE). In two experiments, seeds of the three Prosopis species were grown in conspecific and congeneric soils, and litter was collected from underneath their canopies. Prosopis juliflora and P. pallida seedlings, on average, formed a higher number of nodules than native P. cineraria seedlings. Prosopis juliflora seedlings had the heaviest dry shoots and nodules, whereas P. pallida had the heaviest dry roots. The soil source played an important role in the nodule production of each species, with P. pallida and P. cineraria seedlings producing more nodules when growing in conspecific soils. Nodulation and growth were generally reduced across all species when conspecific litters were added, with P. juliflora being the least affected. The success of non-native invasive Prosopis trees in their introduced ranges could be attributed to their capacity to nodulate profusely and to use the biologically fixed nitrogen to enhance aboveground growth in soils with low nitrogen content.

This study assessed differences in the physical, chemical, and microbial properties of soils under trees of the native species Prosopis cineraria and the invasive species Prosopis juliflora trees, focusing on implications for ecosystem management and restoration. At the start of the growing season, 30 trees of each species with a trunk diameter of 15–30 cm were randomly selected. Soil samples were taken from the top 20 cm of soil profiles east of each tree, under the tree crowns and from control plots in open areas. Three soil samples per site were pooled for chemical and microbial analysis. Soil moisture was highest under P. cineraria (14.64 ± 0.3) and lowest in control plots (9.04 ± 0.65). Soil pH was highest in control soils (7.91 ± 0.09), slightly lower under P. cineraria (7.77 ± 0.06), and lowest under P. juliflora (7.49 ± 0.0). Electrical conductivity, soil salinity was highest under P. juliflora (2.25 ± 0.12). Microbial activity indicators (basal respiration and microbial biomass carbon) were greater under P. cineraria than under P. juliflora trees. Native P. cineraria trees enhance soil conditions, benefiting ecosystem management. In contrast, invasive P. juliflora trees raise soil salinity, threatening soil quality, biodiversity, and ecosystem services in the Sahara-Sahel region. Managing the spread of P. juliflora is crucial to maintaining ecosystem functions.

There are 230 UNESCO World Heritage Sites that were designated based on their important natural features. These represent some of the most iconic and important natural places on Earth, with immense value for biodiversity conservation, ecosystem service supply and cultural well-being. Many of these sites are degraded by anthropogenic drivers, including socioeconomic factors (population growth, poverty and tourism), extractive activities (logging, mining, and hunting), external threats (fire, climate change, land-use change, pollution), and biological threats (disease and invasive species). Of these, invasive species remain one of the most problematic for management, and once introduced, populations can grow exponentially and spread to other locations even when actively managed. Given the economic and environmental threats imposed by invasive species, we asked how they compare to the other anthropogenic threats. We reviewed the primary literature for each World Heritage Site and scored the prevalence of 12 different anthropogenic drivers. We found that invasive species rank as one of the most frequently identified threats and pose the greatest degree of concern compared to all other threats, on par with the threat from pollution and greater than logging, land-use change and climate change. We compared our scoring, based on review of the literature, with that of the UNESCO and IUCN monitoring reports. Although there was general agreement between these two assessments, the literature provided information on 55 sites not included in the monitoring reports. We further examine the invasive species examined in the articles and the degree of their perceived impacts on biodiversity, habitat, rare species, ecosystem function, tourism, and economic impacts. It is important that invasive species are well monitored and managed in WHSs to reduce their impacts and meet policy mandated targets and conservation goals.

Forests are under pressure and going through rapid changes. However, current inventorying and monitoring (IM) programs are often either disjointed, too narrow in their scope and/or do not operate at fine enough temporal resolutions, which may hinder scientific understanding, the timely supply of information, fast decision making, and may result in the sub-optimal use of resources. For these reasons, there is an urgent need for Advanced Forest Inventorying and Monitoring (AIM) programs to (i) achieve expanded relevance (by augmenting data/information across ecosystem properties and trophic levels), (ii) have increased temporal resolution (by tailored data collection frequency), and (iii) make use of technological advances (by incorporating novel tools and technologies). The Advanced Inventorying and Monitoring for Swiss Forests (SwissAIM) initiative was launched in 2020 to address these needs. SwissAIM builds upon the foundation offered by the existing programs (e.g., national forest inventory, long-term forest ecosystem research, biodiversity monitoring). It aims to offer a collaborative and adaptive framework to enable integrated data collection, evaluation, interpretation, analysis, and modeling. Ideally, it will result in a more responsive system with respect to current and predicted biotic/abiotic stressors that will challenge Swiss forests. Developing such a system implies identifying the information needs of different stakeholders (e.g., science, policy, practice), related technical requirements, and governance frameworks. Here, we present (i) the main features of the SwissAIM initiative (vision, scientific questions and variables, governance and engagement), (ii) the main outcomes of the participatory design process (measurements, sampling, and plot design), (iii) the potential transferability of AIM initiatives outside Switzerland (timing, relevance, practicability), and (iv) the key messages that emerged (i.e., need for advancement, integration and transdisciplinarity, statistical underpinning). Since similar needs related to forest inventorying and monitoring are emerging throughout Europe and elsewhere, the objective of this opinion paper is to share our experience and promote a dialog with those interested in developing AIM initiatives in other countries and regions.

In a hyperconnected world, framing and managing biological invasions poses complex and contentious challenges, affecting socioeconomic and environmental sectors. This complexity distinguishes the field and fuels polarized debates. In the present article, we synthesize four contentious issues in invasion science that are rarely addressed together: vocabulary usage, the potential benefits of nonnative species, perceptions shifting because of global change, and rewilding practices and biological invasions. Researchers have predominantly focused on single issues; few have addressed multiple components of the debate within or across disciplinary boundaries. Ignoring the interconnected nature of these issues risks overlooking crucial cross-links. We advocate for interdisciplinary approaches that better integrate social and natural sciences. Although they are challenging, interdisciplinary collaborations offer hope to overcome polarization issues in invasion science. These may bridge disagreements, facilitate knowledge exchange, and reshape invasion science narratives. Finally, we present a contemporary agenda to advance future research, management, and constructive dialogue.

Research that directs the way stakeholders act and how they collaborate is essential when addressing complex environmental challenges in the field of sustainability science. For example, researchers attempting to manage Prosopis invasions through biological control in South Africa have historically faced challenges from stakeholders. In this study, we illustrate the importance of stakeholder engagement and social learning by outlining the collaborative efforts of various stakeholders to promote effective, integrative and sustainable management of Prosopisinvasions in the Northern Cape, South Africa. Through a community of practice approach, stakeholders worked together over the past half-decade in an attempt to develop a National Strategy for Prosopis management and improve its control. This strategy aimed not only to emphasise the need for integration of biomass use (aimed at offsetting the costs of mechanical clearing and necessary herbicide use) but also to underscore the significance of biocontrol alongside other management approaches. Stakeholders also identified that adequate farm-scale planning is necessary to provide a sense of purpose and assist in monitoring of progress. We worked alongside land managers and experts to develop such plans. The engagement of local champions played a crucial role in facilitating collaboration and learning among stakeholders, emphasising the significance of inclusive approaches in addressing complex sustainability challenges. In addition, we gained an understanding of how to develop the community of practice to enhance collaboration that ensures the implementation of plans to better manage Prosopis. Our findings underscore the necessity of meaningful stakeholder engagement and collaboration in effective invasive species management. By promoting understanding and involvement of diverse stakeholders, initiatives can have a greater impact in addressing broader sustainability issues.

Biological invasions can have major social-ecological consequences for rural communities across the world. However, the dimensions (characteristics, infestation and socio-ecological impacts) of emerging invasive alien plants are often less known and urgent information is needed to guide policy and management. In light of this, this paper assesses the social-ecological impacts of Vernonanthura polyanthes, an emerging invasive alien plant found in a Zimbabwean upland landscape which supports conservation and livelihoods. The paper employs qualitative methods—community mapping, time series analysis, and key informant interviews—involving individuals from diverse socio-economic backgrounds, to examine the socio-ecological and economic implications of V. polyanthes and its management in Chimanimani, Zimbabwe. We found that there are nuanced perspectives regarding this invasive alien plant among different socio-economic groups in the region who have different experiences of living with V. polyanthes. Some are embracing it for apiculture, firewood, and ethnomedicine while, on the other hand, some see the tree as negatively affecting key livelihoods (crop farming, pastoralism, and tourism) that are common in the region. Local people also identified that V. polyanthes is associated with ecological impacts that include loss of biodiversity, promoting pests, and negatively affecting watersheds and associated water sources. These mixed experiences concerning the plant are leading to different management practices, in turn inducing some conflicts among various actors. Based on our findings, we suggest more should be done to better manage this invasive alien plant in the region before negative impacts become too great, particularly in protected areas.

Laut einer Studie hat das Bohrkernentnehmen keine nachweisbaren Auswirkungen auf das Wachstum und die Sterblichkeit von Bäumen. Die Methode könnte also öfter eingesetzt werden, um die Reaktion der Wälder auf veränderte Umweltbedingungen besser zu verstehen.

1. A large number of non-native trees (NNTs) have been introduced globally and widely planted, contributing significantly to the world's economy. Although some of these species present a limited risk of spreading beyond their planting sites, a growing number of NNTs are spreading and becoming invasive leading to diverse negative impacts on biodiversity, ecosystem functions and human well-being. To help minimize the negative impacts and maximize the economic benefits of NNTs, Brundu et al. developed eight guidelines for the sustainable use of NNTs globally—the Global Guidelines for the Use of NNTs (GG-NNTs).
2. Here, we used an online survey to assess perceptions of key stakeholders towards NNTs, and explore their knowledge of and compliance with the GG-NNTs.
3. Our results show that stakeholders are generally aware that NNTs can provide benefits and cause negative impacts, often simultaneously and they consider that their organization complies with existing regulations and voluntary agreements concerning NNTs. However, they are not aware of or do not apply most of the eight recommendations included in the GG-NNTs.
4. We conclude that effectively managing invasions linked to NNTs requires both more communication efforts using an array of channels for improving stakeholder awareness and implementation of simple measures to reduce NNT impacts (e.g. via GG-NNTs), and a deeper understanding of the barriers and reluctance of stakeholders to manage NNT invasions. Read the free Plain Language Summary for this article on the Journal blog.

Selon une étude, le prélèvement de carottes n'a pas d'effet détectable sur la croissance et la mortalité des arbres. Cette méthode pourrait donc être utilisée plus fréquemment pour aider à mieux comprendre la réaction des forêts à l'évolution des conditions environnementales.

Tree cores are a highly valuable scientific resource. Annual growth ring data can, for example, improve our understanding of climate change impacts and effects of environmental pollution, allow for better annual estimations of tree growth patterns and carbon storage, and help quantify dynamics and changes in forest ecosystems. The value of coring trees for research has been weighted against concerns around the potential harm coring might cause to trees. To date, there is indeed limited research accurately quantifying the potential effects of coring on tree growth and only a handful of studies assessing its influence on mortality. Consequently, many European long-term forest inventorying and monitoring programs are concerned that tree coring might bias the repeated tree measurements in permanent plots, which they rely on for assessments of states and changes of forests. In this study, we assessed the effects of tree coring on the growth and mortality of three widespread European tree species approximately 10 years after they were cored. We used repeated tree measurements from permanent research sites in Switzerland and Ukraine. In Switzerland, we assessed 35 cored and 159 uncored Norway spruce (Picea abies) trees as well as 147 cored and 332 uncored silver fir (Abies alba) trees. In Ukraine, we assessed 348 cored and 6'611 uncored European beech (Fagus sylvatica) trees. We found no statistical evidence that coring negatively affected the growth or mortality of the three tree species assessed. Although we cannot rule out subtle effects on tree health and wood quality, our findings do not provide any evidence that coring affects or biases repeated measurements (such as DBH measures and recording of mortality) performed on the investigated tree species. Tree coring could therefore be considered more often for routine incorporation, particularly in long-term forest inventorying and monitoring programs and initiatives.

Power is important and inherent in inter and transdisciplinary (ITD) research and the implementation of research findings (policy and practice). Power shapes what we know, how we do science and how it is implemented and by whom, making it an important topic to consider in research design and research implementation. For example, power influences the language and terminology we use, the social-demographic makeup of research teams and which ideologies prevail in ITD research. Here we introduce the four most common approaches to identifying and understanding power including: i) actor-centred, ii) institutional, iii) structural, and, iv) discursive power, and how they affect ITD research and practice. We also introduce different analytical framings of power including: "power-over" "power-with", "power-to" and other approaches like Transformative Power Lab. Acknowledging and addressing power-related challenges and imbalances will inherently help to improve ITD research and practice through, for example, promoting inclusivity, reflexivity and empowerment, improving transparency, building trust and collaboration among stakeholders and possibly mitigating against conflicts.

Resilience is a cross-cutting and boundary concept often applied in inter- and transdisciplinary (ITD) research and practice. The concept has been theorised and understood across various disciplines and is also applied in practice by governments and NGOs through resilience-building initiatives. In the context of ITD, resilience can be defined as the ability (of a person, community, infrastructure, ecological system, economic system, social-ecological system, etc.) to cope with, absorb, recover from, adapt to, or transform in response to a change, shock, disturbance or stressor to ensure desired outcomes. In practice, building resilience involves drawing on a variety of approaches to improve the capacity of a system or community to deal with change and deliver positive outcomes. This often relates to enhancing anticipatory, absorptive, adaptive and transformative capacities. Yet, given that the preferred changes and outcomes are normatively valued among different actors and stakeholders, additional complexity is introduced.

Social-ecological systems (SES) research adopts a complex adaptive systems approach that links human societies and natural systems as well as their interactions together. SES research is frequently applied in addressing the governance of interlinked global change challenges for advancing sustainable development. It frequently emphasises action-oriented outcomes, with many SES projects aiming to make meaningful contributions to policy and practice. Consequently, SES projects commonly incorporate participatory research approaches and stakeholder engagement into their methodologies. In the realm of SES, universal theories are generally not favoured or considered highly desirable due to the context-dependent nature of the field. Instead, researchers and practitioners often rely on various organising frameworks to guide their work. Approximately 30 distinct sets of methods employed in SES research have been identified. Projects often go beyond the application of specific social or natural science approaches and adapt and integrate different methods, frameworks and approaches together to capture the different aspects of SES and their interactions coherently. As such SES helps to promote inter- and transdisciplinary work.

Vietnam is the country with the largest area of plantations of Australasian Acacia species ('wattles') in South-East Asia. Between 6 and 9% of the national land area is cultivated with tropical wattles (A. auriculiformis, A. mangium and its hybrid). From the perspective of its promoters, the wattle plantation industry in Vietnam may be seen as a success beyond expectations. We review the origins of this boom and ask what it has done to and for the country's landscape and people. The chapter combines findings and insights from an interdisciplinary research project in Thừa Thiên Huế province, north-central Vietnam. Research took place across upland and lowland wattle-growing regions, with ethnic minorities as well as the Kinh majority, and with long-term wattle growers as well as new entrants. It drew on questionnaires, interviews and observations, as well as information from remote sensing, ecological surveys and hydrological assessments. We first describe how substantial areas of 'new forest' (short-rotation wattle plantations) were created, initially in degraded bushland, but now sometimes through clearing of highly biodiverse natural forest stands. These wattle plantations alter local hydrology, soils and biodiversity, and are exposed to risks including soil erosion and plant pathogens. The plantations provide wood chips and timber, supporting revenue, employment and a strong forestry industry. Incomes have risen appreciably for many, although unequally, and a class of successful entrepreneurs has emerged. These plantations alter the livelihoods and identities of upland 'forest people', historically shifting cultivators, contributing to what might be called 'new forest people'. Ethnic minority villagers are building new identities around the wattle economy and around their contracts with state forest agencies, seeing themselves increasingly as forest growers and protectors. We conclude by raising some questions regarding the social changes and issues of environmental sustainability linked to this wattle boom.

Over the last decades, Vietnam has seen substantial shifts in forest landscape uses and associated livelihoods. We document the livelihood transformations in Nam Dong, a mountainous district of Central Vietnam, where land uses have changed from the utilisation of products from natural forests and shifting cultivation (swidden agriculture) to acacia tree-dominated plantation forestry. Forestry policies (forestland allocation, plantation development agendas), the increase in the economic value of acacia, and household livelihood assets are the primary factors driving these changes. We also found that there are differences in the access to and ownership of forestland with regard to households of different communities and between poor vs wealthy households. Therefore, careful attention needs to be paid to guide future land use policies in the area to foster social and ecological sustainability.

Conservation research and practice are increasingly engaging with people and drawing on social sciences to improve environmental governance. In doing so, conservation engages with power in many ways, often implicitly. Conservation scientists and practitioners exercise power when dealing with species, people and the environment, and increasingly they are trying to address power relations to ensure effective conservation outcomes (guiding decision-making, understanding conflict, ensuring just policy and management outcomes). However, engagement with power in conservation is often limited or misguided. To address challenges associated with power in conservation, we introduce the four dominant approaches to analyzing power to conservation scientists and practitioners who are less familiar with social theories of power. These include actor-centered, institutional, structural, and, discursive/governmental power. To complement these more common framings of power, we also discuss further approaches, notably non-human and Indigenous perspectives. We illustrate how power operates at different scales and in different contexts, and provide six guiding principles for better consideration of power in conservation research and practice. These include: (1) considering scales and spaces in decision-making, (2) clarifying underlying values and assumptions of actions, (3) recognizing conflicts as manifestations of power dynamics, (4) analyzing who wins and loses in conservation, (5) accounting for power relations in participatory schemes, and, (6) assessing the right to intervene and the consequences of interventions. We hope that a deeper engagement with social theories of power can make conservation and environmental management more effective and just while also improving transdisciplinary research and practice.

The selection of species for restoration projects requires decision-making to be based on scientific evidence as well as input and approval from local communities. To better guide future restoration initiatives, this study assessed the socio-ecological effects of two Prosopis congeners including the native Prosopis cineraria and the non-native P. juliflora (mesquite) in two different sites in Southern Iran. Soil parameters including pH, electrical conductivity, organic carbon, and total nitrogen as well as vegetation indices including native vegetation cover, diversity, and density were measured under both of the congener tree species. Furthermore, pastoralists' perceptions toward the colonizing ability of both Prosopis congeners, their impacts on ecosystem services, and people's livelihoods and human well-being were assessed through interviews and semi-structured questionnaires. The ecological results showed that areas with native P. cineraria had higher native vegetation cover, density, and diversity as compared to sites with the non-native P. juliflora. Soils under P. cineraria and P. juliflora generally showed similar properties, with some small differences between sites (especially for pH and nitrogen). The social results showed that pastoralists in both study regions perceived P. cineraria to be better for local ecosystem services and livelihoods and viewed it to have lower colonizing or invasion potential. It can be concluded that native P. cineraria is a better candidate for restoration because it provides more ecological and social benefits and poses fewer long-term threats. Caution should be taken when promoting non-native species such as P. juliflora for restoration.

Vietnam is undergoing a forest transition stage with an overall increase in forest cover since the 1990s; however, deforestation and forest degradation of natural forests still occur in several areas, especially in the Central region of the country. In order to better manage and protect natural forests, predicting deforestation probability and understanding its associated factors are necessary. In the present study, we focused on the two mountainous districts (Nam Dong and A Luoi) in Central Vietnam as a case study. We used Landsat satellite images for identifying changes of natural forests over the period of 1989–2020. The logistic regression model showed a good performance in prediction of deforestation (testing AUC = 0.874) in the study area. Our data showed that deforestation probability of natural forests in the study area in the period of 1989–2020 could be influenced by 11 socio-economic and topographical factors. In particular, forest areas with low elevation, gentle slopes, nearby rivers and residential areas have a high deforestation probability. Production forest, forest areas not included in payment for environmental service (PFES) schemes, forest with no ownership and forest areas managed by private owners may also have a high deforestation probability. The total area of very high level of deforestation probability in A Luoi (8,988 ha) and Nam Dong (5,304 ha) districts occupied about 11.4% of natural forests in the study area. Our study suggests that protection activities should be focused on high deforestation probability-prone forest areas.