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Australian Acacia species (‘wattles’) have been widely introduced outside Australia and some now rank among the most widespread and damaging invasive trees globally. Early-warning systems that monitor the establishment and spread of alien species or track their distribution are required to aid scientists, policy makers, land managers and other stakeholders in the prevention of further wattle introductions and the control of invasive populations already established.This chapter provides an overview of commonly used models to study wattle invasions and, specifically, modelling approaches aimed at predicting invasiveness that are useful for the early warning, assessment and monitoring of wattles. A systematic review of published literature is first conducted to understand the spatial-temporal extent of modelling applications across different wattle species, and to provide an overview on the main modelling techniques and types of data adopted in wattle research. Applications of these models are then illustrated by a set of case studies, specifically focused on the use of (i) remote sensing data, (ii) citizen science data and (iii) the application of dynamic models to address wattle invasions.The chapter integrates ideas and examples that can be useful for guiding the prediction of future wattle introductions, establishment and invasions. Even though modelling tools have their limitations, they allow the study of real-world problems through testing hypotheses and analysing potential scenarios, which is useful to address topics like the adaptive management of ever-shifting social-ecological systems, such as invasive wattles.

In many parts of the world, agriculture is threatened by climate change and land degradation in the form of soil erosion. Soil erosion involves the loss of fertile topsoil and reduction of soil productivity, as well as increased mobilization of sediment and delivery to rivers. Sedimentation of water bodies is especially problematic in arid regions where water scarcity is frequent. Furthermore, the dynamics of soil erosion and deposition processes substantially affects the redistribution of soil carbon in the landscapes. Despite being a significant risk to soil and water resources, soil erosion is an overlooked threat, especially in terms of climate change due to increased soil carbon emissions. Considerable discussion still exists about whether erosion results in enhanced emissions of carbon to the atmosphere (C source) or enhanced sequestration of carbon in the soil (C sink). More scientific information is essential to assess the role and impact of soil erosion on the terrestrial carbon budget, highlighting the effect of topography, soil type, land use/land cover and soil management. Another question of importance is the “intra-storage” of mobilized soil and carbon along the hillslopes and in different compartments within catchments. Driving factors of soil carbon distribution and the role of sediment connectivity across the landscape induced by erosion remain largely unknown. This session combines contributions on soil erosion and soil carbon at hillslope, small or large catchment scale in different agroecosystems, including both agricultural and forestry landscapes, using a diverse set of tools and data analyses such as field measurements, monitoring techniques, remotely sensed and GIS analyses, modelling, isotopic and non-isotopic erosion tracers, fingerprinting techniques, among others. Let’s come together and share findings, views and concepts to better understand soil erosion processes and its effect on the landscape-scale distribution of soil carbon.

Evolutionary processes greatly impact the outcomes of biological invasions. An extensive body of research suggests that invasive populations often undergo phenotypic and ecological divergence from their native sources. Evolution also operates at different and distinct stages during the invasion process. Thus, it is important to incorporate evolutionary change into frameworks of biological invasions because it allows us to conceptualize how these processes may facilitate or hinder invasion success. Here, we review such processes, with an emphasis on tree invasions, and place them in the context of the unified framework for biological invasions. The processes and mechanisms described are pre-introduction evolutionary history, sampling effect, founder effect, genotype-byenvironment interactions, admixture, hybridization, polyploidization, rapid evolution, epigenetics and secondgenomes. For the last, we propose that co-evolved symbionts, both beneficial and harmful, which are closely physiologically associated with invasive species, contain critical genetic traits that affect the evolutionary dynamics of biological invasions. By understanding the mechanisms underlying invasion success, researchers will be better equipped to predict, understand and manage biological invasions.

Non-native trees have become dominant components of many landscapes, including urban ecosystems, commercial forestry plantations, fruit orchards and as invasives in natural ecosystems. Often, these trees have been separated from their natural enemies (i.e. insects and pathogens) leading to ecological disequilibrium, that is, the immediate breakdown of historically co-evolved interactions once introduced into novel environments. Long-established, non-native tree plantations provide useful experiments to explore the dimensions of such ecological disequilibria. We quantify the status quo of non-native insect pests and pathogens catching up with their tree hosts (planted Acacia, Eucalyptus and Pinus species) in South Africa, and examine which native South African enemy species utilize these trees as hosts. Interestingly, pines, with no confamilial relatives in South Africa and the longest residence time (almost two centuries), have acquired only one highly polyphagous native pathogen. This is in contrast to acacias and eucalypts, both with many native and confamilial relatives in South Africa that have acquired more native pathogens. These patterns support the known role of phylogenetic relatedness of non-native and native floras in influencing the likelihood of pathogen shifts between them. This relationship, however, does not seem to hold for native insects. Native insects appear far more likely to expand their feeding habits onto non-native tree hosts than are native pathogens, although they are generally less damaging. The ecological disequilibrium conditions of non-native trees are deeply rooted in the eco-evolutionary experience of the host plant, co-evolved natural enemies and native organisms from the introduced range. We should expect considerable spatial and temporal variation in ecological disequilibrium conditions among non-native taxa, which can be significantly influenced by biosecurity and management practices.

Novel species of fungi described in this study include those from various countries as follows: Australia: Apiognomonia lasiopetali on Lasiopetalum sp., Blastacervulus eucalyptorum on Eucalyptus adesmophloia, Bul- lanockia australis (incl. Bullanockia gen. nov.) on Kingia australis, Caliciopsis eucalypti on Eucalyptus marginata, Celerioriella petrophiles on Petrophile teretifolia, Coleophoma xanthosiae on Xanthosia rotundifolia, Coniothyrium hakeae on Hakea sp., Diatrypella banksiae on Banksia formosa, Disculoides corymbiae on Corymbia calophylla, Elsinoe¿ eelemani on Melaleuca alternifolia, Elsinoe¿ eucalyptigena on Eucalyptus kingsmillii, Elsinoe¿ preissianae on Eucalyptus preissiana, Eucasphaeria rustici on Eucalyptus creta, Hyweljonesia queenslandica (incl. Hyweljonesia gen. nov.) on the cocoon of an unidentified microlepidoptera, Mycodiella eucalypti (incl. Mycodiella gen. nov.) on Eucalyptus diversicolor, Myrtapenidiella sporadicae on Eucalyptus sporadica, Neocrinula xanthorrhoeae (incl. Neocrinula gen. nov.) on Xanthorrhoea sp., Ophiocordyceps nooreniae on dead ant, Phaeosphaeriopsis agava- cearum on Agave sp., Phlogicylindrium mokarei on Eucalyptus sp., Phyllosticta acaciigena on Acacia suaveolens, Pleurophoma acaciae on Acacia glaucoptera, Pyrenochaeta hakeae on Hakea sp., Readeriella lehmannii on Eucalyptus lehmannii, Saccharata banksiae on Banksia grandis, Saccharata daviesiae on Daviesia pachyphylla, Saccharata eucalyptorum on Eucalyptus bigalerita, Saccharata hakeae on Hakea baxteri, Saccharata hakeicola on Hakea victoria, Saccharata lambertiae on Lambertia ericifolia, Saccharata petrophiles on Petrophile sp., Sac- charata petrophilicola on Petrophile fastigiata, Sphaerellopsis hakeae on Hakea sp., and Teichospora kingiae on Kingia australis. Brazil: Adautomilanezia caesalpiniae (incl. Adautomilanezia gen. nov.) on Caesalpina echinata, Arthrophiala arthrospora (incl. Arthrophiala gen. nov.) on Sagittaria montevidensis, Diaporthe caatingaensis (en- dophy

Novel species of fungi described in the present study include the following from Australia: Neoseptorioides eucalypti gen. & sp. nov. from Eucalyptus radiata leaves, Phytophthora gondwanensis from soil, Diaporthe tulliensis from rotted stem ends of Theobroma cacao fruit, Diaporthe vawdreyi from fruit rot of Psidium guajava, Magnaporthiopsis agrostidis from rotted roots of Agrostis stolonifera and Semifissispora natalis from Eucalyptus leaf litter. Furthermore, Neopestalotiopsis egyptiaca is described from Mangifera indica leaves (Egypt), Roussoella mexicana from Coffea arabica leaves (Mexico), Calonectria monticola from soil (Thailand), Hygrocybe jackmanii from littoral sand dunes (Canada), Lindgomyces madisonensis from submerged decorticated wood (USA), Neofabraea brasiliensis from Malus domestica (Brazil), Geastrum diosiae from litter (Argentina), Ganoderma wiiroense on angiosperms (Ghana), Arthrinium gutiae from the gut of a grasshopper (India), Pyrenochaeta telephoni from the screen of a mobile phone (India) and Xenoleptographium phialoconidium gen. & sp. nov. on exposed xylem tissues of Gmelina arborea (Indonesia). Several novelties are introduced from Spain, namely Psathyrella complutensis on loamy soil, Chlorophyllum lusitanicum on nitrified grasslands (incl. Chlorophyllum arizonicum comb. nov.), Aspergillus citocrescens from cave sediment and Lotinia verna gen. & sp. nov. from muddy soil. Novel foliicolous taxa from South Africa include Phyllosticta carissicola from Carissa macrocarpa, Pseudopyricularia hagahagae from Cyperaceae and Zeloasperisporium searsiae from Searsia chirindensis. Furthermore, Neophaeococcomyces is introduced as a novel genus, with two new combinations, N. aloes and N. catenatus. Several foliicolous novelties are recorded from La Réunion, France, namely Ochroconis pandanicola from Pandanus utilis, Neosulcatispora agaves gen. & sp. nov. from Agave vera-cruz, Pilidium eucalyptorum from Eucalyptus robusta, Strelitziana syzygii from Syzygium