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Questions: Pollen traits (e.g., size, wall thickness, number of apertures) have been suggested to be relevant in terms of pollination mechanisms and the ability of the male gametophyte to withstand desiccation. We examined the spatiotemporal distribution of pollen traits related to dispersal (ornamentation and dispersal unit) and desiccation tolerance (wall thickness, presence of furrows and pores and pollen size). Specifically, we address two questions: how are the pollen traits distributed in relation to different levels of aridity? And, how did the pollen trait composition change with changing past environmental conditions? Location: Laurel forests of La Gomera and Tenerife (Canary Islands). Methods: We used pollen rain from 19 forest plots on an elevational gradient of 1050 m and all laurel forest types (cold, dry, humid and ridge crest) to quantify pollen trait composition using community‐weighted means. In addition, we used fossil pollen to examine the composition of pollen traits over 9600 years in response to known intervals of regional past climate change. Results: Our results demonstrated increased prevalence of desiccation tolerance‐related pollen traits over drier areas of the laurel forest distribution. We also found increased prevalence of rich pollen grain ornamentation in the core of the laurel forest distribution. Holocene pollen functional diversity increased during a trend towards drier conditions as did the proportion of pollen grains with apertures and thicker walls to indicate desiccation tolerance. Conclusions: Our study provides the first step towards understanding the role of pollen traits when quantifying the dynamics of different plant communities. [ABSTRACT FROM AUTHOR]

The Spanish conquest of the Cuchumatanes Highlands (1524–1541 ce) led to dramatic land use changes adhering to colonial practices and values, which included the rearing of livestock, agriculture, timber extraction, mining, and the relocation of indigenous populations to new settlements. These changes are often recorded in historical accounts and official records; however, these are sparse, incomplete, and have been lost over the passage of time. Here, we present a high-resolution palaeoenvironmental reconstruction for Cenote Kail (Guatemala) since the Spanish Conquest, to provide additional evidence of land use changes from an integrated multi-proxy perspective. We analysed: (i) fossil pollen; (ii) macroscopic and microscopic charcoal; and (iii) dung fungal spores (Sporormiella) from a lake sediment core extracted from Cenote Kail in the Cuchumatanes highlands, combining these analyses with remotely sensed satellite data. We reconstructed: (i) forest composition and dynamics; (ii) burning, (iii) fauna abundance, and (iv) agricultural activities. High resolution age-depth modelling was conducted using a combination of 210Pb and 14C dates. The high temporal resolution enabled a novel integrated validation of the charcoal data sets with remotely sensed satellite data and the historical record. Three stages of floral compositional change were discerned from the palynological assemblage data encompassing: (i) the decline of mixed hard wood forests (MHWF), associated with the building of new settlements, agriculture and timber extraction for fuel (1550–1675 ce); (ii) pastoral expansions involving the rearing of livestock (1700–1800 ce); and (iii) the expansions of urban settlements and increasing management of the land (1821–2015 ce). Seed predation is suggested as the dominant factor preventing MHWF from re-establishing in the Cuchumatanes Highlands over the past 500 years. Burning is limited locally and regionally and in line with the modern regime, which suggests that fire has been managed and controlled since European contact. [ABSTRACT FROM AUTHOR]

Islands are among the last regions on Earth settled and transformed by human activities, and they provide replicated model systems for analysis of how people affect ecological functions. By analyzing 27 representative fossil pollen sequences encompassing the past 5000 years from islands globally, we quantified the rates of vegetation compositional change before and after human arrival. After human arrival, rates of turnover accelerate by a median factor of 11, with faster rates on islands colonized in the past 1500 years than for those colonized earlier. This global anthropogenic acceleration in turnover suggests that islands are on trajectories of continuing change. Strategies for biodiversity conservation and ecosystem restoration must acknowledge the long duration of human impacts and the degree to which ecological changes today differ from prehuman dynamics. [ABSTRACT FROM AUTHOR]

Contrary to expectations, some human-modified landscapes are considered to sustain both human activities and biodiversity over the long-term. Agroforestry systems are among these landscapes where crops are planted under native shade trees. In this context, ancient agroforestry systems can provide insight into how farmers managed the landscape over time. Such insight can help to quantify the extent to which tropical forests (especially habitat-specialist trees) are responding to local and landscape-level management. Here, we extracted fossil pollen (indicator of past vegetation changes) and macroscopic charcoal (indicator of biomass burning) from four forest hollows’ sedimentary sequences in an ancient agroforestry system in Western Ghats, India. We used a mixed-modelling approach and a principal components analysis (PCA) to determine past trajectories of forest change and species composition dynamics for the last 900 years. In addition, we reconstructed the long-term forest canopy dynamics and examined the persistence of habitat-specialist trees over time. Our results show that the four sites diverged to a surprising degree in both taxa composition and dynamics. However, despite these differences, forest has persisted over 900 years under agricultural activities within agroforestry systems. This long-term analysis highlights the importance of different land-use legacies as a framework to increase the effectiveness of management across tropical agricultural lands. [ABSTRACT FROM AUTHOR]

This paper presents a study of phytoliths (opal silica bodies from plants) from sediment sequences obtained from two tropical forest patches in the Western Ghats of India: a sacred grove (sequence covers last 550 cal BP) and a forest patch in a plantation (sequence covers last 7500 cal BP). The sites are located at mid-elevation (c. 650–1400 m above sea level) in a mosaic landscape showing anthropogenic open habitats and plantations as well as some evergreen forests. The aim of this paper is to evaluate the landscape composition of grassland and forest over time in the region, grassland being invariably shaped by anthropogenic activities, particularly fire for cultivation. We identified and classified phytoliths into 34 morphotypes from five taxonomic groups: Poaceae (grasses), Cyperaceae (sedges), Arecaceae (palms), Pteridopsida (ferns) and woody dicotyledons (broad-leaved trees and shrubs). We also calculated the humidity–aridity index (Iph). First, our results show that grasses are the most represented phytolith types in both sites, followed by broad-leaved trees and shrubs, palms, sedges, and ferns. Second, the highly variable climatic index Iph over the last 1000 years suggest that changes in phytolith percentage (e.g. broad-leaved trees) might be caused by human agro-pastoral activities, such as clearing through fires and irrigation. Prior to these human activities, the phytolith signal for early Holocene climate is congruent with the existing literature. Finally, this study compares new phytolith results with previous pollen data from the same sites. We find good agreement between these two botanical proxies throughout, thus validating our findings. We provide important evidence regarding the history of environmental change due to anthropogenic activities in the Western Ghats. This has important implications because it provides insights into how tropical forest will respond to increased intensity of human activities. [ABSTRACT FROM AUTHOR]

Crop pollination by bees has long been recognized as an ecosystem service of huge economic value; a large number of food crops depend upon pollination. Features across landscapes that are important for pollination delivery include: nesting habitats, floral resource availability at foraging distance, and climate. The conditions for presence/absence of pollinators are therefore complex and rely upon a combination of biotic and abiotic factors. To date there has been no easily available method for landowners to determine the potential of pollination delivery across the land effectively and rapidly. In this paper we develop a method that uses freely available datasets to remotely estimate the relative provision of pollination service delivery provided by bees across Europe at a 300 m-pixel resolution. We then identify the potential pollination delivery and efficiency across Europe at country and regional level. This study illustrates an approach that obtains a first approximation for land managers to identify potential areas across landscapes to protect in order to enhance pollination service delivery. [ABSTRACT FROM AUTHOR]

We provide the first fossil pollen and charcoal analysis from the island of Gran Canaria (Canary Islands). The pollen record obtained from Laguna de Valleseco (870 m a.s.l.) spans the late Holocene (c. 4500–1500 cal. yr BP) and thereby captures the impact of human colonization. During the earliest period, pollen composition resembled contemporary thermophilous communities, with palms (Phoenix canariensis) and junipers (Juniperus cf. turbinata) being the dominant trees, suggesting that these elements were more widespread in the past. Vegetation in Valleseco began to change at around 2300 cal. yr BP, 400 years before the earliest archaeological evidence of human presence in the island (c. 1900 cal. yr BP). Our data show an increased frequency of fires at that time, coinciding with the decline of palms and the increase of grasses, indicating that humans were present and were transforming vegetation, thus showing that the demise of Gran Canaria’s forest began at an early point in the prehistoric occupation of the island. In the following centuries, there were no signs of forest recovery. Pollen from cultivated cereals became significant, implying the introduction of agriculture in the site, by 1800 cal. yr BP. The next shift in vegetation (c. 1600 cal. yr BP) involved the decrease of grasses in favour of shrubs and trees like Morella faya, suggesting that agriculture was abandoned at the site. [ABSTRACT FROM AUTHOR]

Biological conservation and environmental management are increasingly focussing on the preservation and restoration of ecosystem services (i.e. the benefits that humans receive from the natural functioning of healthy ecosystems). Over the past decade there has been a rapid increase in the number of palaeoecological studies that have contributed to conservation of biodiversity and management of ecosystem processes; however, there are relatively few instances in which attempts have been made to estimate the continuity of ecosystem goods and services over time. How resistant is an ecosystem service to environmental perturbations? And, if damaged, how long it does it take an ecosystem service to recover? Both questions are highly relevant to conservation and management of landscapes that are important for ecosystem service provision and require an in-depth understanding of the way ecosystems function in space and time. An understanding of time is particularly relevant for those ecosystem services – be they supporting, provisioning, regulating or cultural services that involve processes that vary over a decadal (or longer) timeframe. Most trees, for example, have generation times >50 years. Understanding the response of forested ecosystems to environmental perturbations and therefore the continuity of the ecosystem services they provide for human well-being – be it for example, carbon draw-down (regulating service) or timber (provisioning service) – requires datasets that reflect the typical replacement rates in these systems and the lifecycle of processes that alter their trajectories of change. Therefore, data are required that span decadal to millennial time-scales. Very rarely, however, is this information available from neo-ecological datasets and in many ecosystem service assessments, this lack of a temporal record is acknowledged as a significant information gap. This review aims to address this knowledge gap by examining the type and nature of palaeoecological datasets that might be critical to assessing the persistence of ecosystem services across a variety of time scales. Specifically we examine the types of palaeoecological records that can inform on the dynamics of ecosystem processes and services over time – and their response to complex environmental changes. We focus on three key areas: a) exploring the suitability of palaeoecological records for examining variability in space and time of ecosystem processes; b) using palaeoecological data to determine the resilience and persistence of ecosystem services and goods over time in response to drivers of change; and c) how best to translate raw palaeoecological data into the relevant currencies required for ecosystem service assessments. [ABSTRACT FROM AUTHOR]

Vegetation history in the Canary Islands, one of the most biodiverse regions within Europe, has recently and for the first time, been the subject of palaeoecological studies. The interpretation of fossil records may be limited by several uncertainties regarding how well the different vegetation types are represented in the pollen rain. In this study we address this key knowledge gap within Canarian vegetation science, taking the island of Tenerife as a model. Based on quantitative and qualitative data we analysed pollen–vegetation relationships to test whether different vegetation types can be discriminated by means of their pollen rain composition, to identify under- and over-represented taxa, and to test the match between modern pollen rain and fossil pollen assemblages. We found clear differences in pollen composition and abundance among major Canarian vegetation types. We also identified good indicator taxa of the local occurrence of their source plants by their high fidelity and low dispersibility index scores. Extra-regional types (taxa without potential source plants in the Canary Islands) were not detected in our traps. However, several important floristic elements are either over-represented ( Pinus , Morella and Ericaceae trees, Chenopodiaceae, Poaceae, Rumex and Urticaceae herbs and shrubs) or under-represented (Lauraceae trees, Fabaceae and Euphorbia shrubs). Results indicate that pollen composition is a good reflection of vegetation in Canarian ecosystems and can be used effectively to reconstruct past environments. [ABSTRACT FROM AUTHOR]

Aim The aim of the present study was to describe the diversity patterns along elevational gradients that are crucial for conservation management and for understanding diversification processes in montane environments. This article analyses the distributional range and elevation patterns of endemic and non-endemic (NE) vascular plants living on a unique set of Neotropical table mountains ( tepuis). To investigate the potential causes of the high degree of diversity and endemism we tested the role of elevation, area and the mid-domain effect (MDE). We also aimed to discuss the origin of the current tepuian biota. Location The Guayana Highlands (northern South America). Emphasis is placed on the mountaintops above 1500 m elevation, which form the highly biodiverse Pantepui biogeographical province. Methods We examined the distribution patterns of vascular plant species richness in relation to elevation, area, and the MDE using generalized additive models. We used Range Model for the MDE. Results We found that regional endemics richness show a hump-shaped curve in relation to elevation. Single-tepui endemics (STE) increase with elevation, whereas NE and total species richness decrease. Area and MDE influence this pattern for Pantepui and STE, but not for NE. We also observed that the spatial distribution of endemic richness displays a left-skewed distribution pattern due to the dominance of STE. Main conclusions Our results demonstrate that a combination of elevation, area and MDE provide a basic explanation for the diversity of vascular plants in Pantepui. In addition, the present study indicates that maxima of STE are located at the highest altitudes, where the possibility of biotic connection (via migration) and gene flux has been minimal, even during glacial phases when most migration pathways amongst the tepui mountains were open. We also suggest that climatic filtering due to the extreme conditions atop the tepuis and low dispersal capacity stand out as the main drivers of the decline in NE species richness with elevation. [ABSTRACT FROM AUTHOR]

Garajonay National Park in La Gomera (Canary Islands) contains one of the largest remnant areas of a forest formation once widespread throughout Europe and North Africa. Here, we aim to address the long-term dynamics (the last 9600 cal. years) of the monteverde forest (laurel forest and Morella-Erica heath) located close to the summit of the National Park (1487 m a.s.l.) and determine past environmental and human impacts., We used palaeoecological (fossil pollen, microscopic and macroscopic charcoal) and multivariate ecological techniques to identify compositional change in the monteverde forest in relation to potential climatic and human influences, based on the analysis of a core site at 1250-m elevation., The regional mid-Holocene change towards drier conditions was matched in this system by a fairly rapid shift in representation of key forest elements, with declines in Canarian palm tree ( Phoenix canariensis), Canarian willow ( Salix canariensis) and certain laurel forest taxa and an increase in representation of the Morella-Erica woody heath., Charcoal data suggest that humans arrived on the island between about 3000 and 1800 years ago, a period of minimal vegetation change. Levels of burning over the last 800 years are among the lowest of the entire 9600 years., Synthesis. A rapid climatic-induced shift of forest taxa occurred 5500 years ago, with a decrease in hygrophilous species in the pollen record. In contrast, we found no evidence of a significant response to human colonization. These findings support the idea that Garajonay National Park is protecting a truly ancient relict, comprising a largely natural rather than cultural legacy. [ABSTRACT FROM AUTHOR]

Abstract: There is growing recognition that the fate of the world’s terrestrial biodiversity depends on the management of human-dominated tropical forest landscapes. While global environmental change is transforming the ecology of tropical forests, a number of studies have also demonstrated that tropical forests are able to recover following disturbance. But are tropical forests resilient to environmental and anthropogenic disturbances over timescales of centuries or millennia? Here we examine the relationship between vegetation cover and variation in monsoon rainfall, soil erosion, and fire over 7500years in an ancient tropical landscape in the Western Ghats of India. We collected two overlapping sediment sequences at one study site and analysed them with palaeoecological techniques to reconstruct vegetation cover. Results suggest that climate and land-use changes might have had synergistic effects on this forested landscape, although the relationship between these factors and vegetation cover has varied over time. Results also indicate that the weakening of monsoon around 5750 BP might have caused a threshold event altering this landscape to a low tree-cover state. Although anthropogenic fire has maintained this landscape in low tree cover state from 3500 BP, this degraded tree–grassland mosaic has remained relatively resilient to fluctuations in environmental and anthropogenic factors. Tree taxa present throughout the sequence have lighter seeds than those absent in parts of the sequence, suggesting that dispersal mode might be an important factor in their persistence. Despite maintaining a degraded and fragmented forest mosaic, however, this landscape has supported populations of heavy-seeded trees and a probable refuge to their dispersal agents. We suggest that retaining tree cover on this landscape, even if fragmented, is key to maintaining its ecological resilience to environmental and anthropogenic disturbance. [Copyright &y& Elsevier]

Abstract: Current global average temperatures are 2°C cooler than during the last interglacial period. The expected increase in temperature during the 21st century will be most stressful for cold-adapted and stenothermic mountain species, forcing them to migrate upwards, and eventually to concentrate into either large areas with favourable climates (refugia) or small stands under locally favourable microclimates (microrefugia). We investigate potential refugia in the neotropical Guayana Highlands mountain biome (Pantepui), consisting of ∼50 isolated table mountains (tepuis), to develop strategies for conserving biodiversity during future global warming. We predict the amount of loss of altitudinal habitats of endemic vascular flora of 26 tepuis and evaluate potential threats to these taxa with respect to species extinction, habitat loss, habitat connectivity and the degree of isolation. We compare past, present and future Pantepui landscape configurations through fragmentation analysis and identify potential in situ refugia. Spatial analysis forecasts more species isolation and declining biodiversity at the end of this century relative to current and past levels. Habitats are predicted to experience >80% loss, with the disappearance of 38 habitat patches. One large patch (Chimantá massif) accounts for 46% of the predicted remaining habitat. This patch can be considered a potential refugium for future vascular flora, as it is predicted to contain some present-day resistant species from lower altitudinal levels and other species eventually persisting in microrefugia. The easternmost Pantepui district, containing the Chimantá massif and other tepuis, seems to be the most suitable for the application of in situ conservation strategies. [Copyright &y& Elsevier]

Abstract: The previously recorded vegetation constancy during most of the Holocene, atop some summits of the Guayana tabular mountains (or tepuis), led to the hypotheses of either environmental stability or site insensitivity. As high-mountain biomes are considered to be especially well suited for recording past environmental changes, a palynological study on the uppermost summit of the Chimantá massif was designed to test its suitability for these purposes. A peat sequence was obtained spanning the last ~13.0cal kyr BP, but an acceptable resolution for paleoecological reconstruction is available only for the last ~4000years. Around 4.3cal kyr BP, the modern vegetation was established and has remained virtually unchanged until today; minor paleoenvironmental changes recorded in other sequences around 2.5cal kyr BP were not detected here. The main paleoclimatic trends are in good agreement with other neotropical records, especially from Lake Valencia and the Cariaco Basin. It is concluded that high-altitude tepuian sites are useful to record paleoenvironmental changes of moderate to high intensity but once a dense vegetation cover is established, gentle shifts remain hidden due to the capacity of plant communities to absorb the changes. The best sites for paleoecological research atop the tepuis are those lying on or near altitudinal ecotones, especially between the meadows and the paramoid shrublands (~2200m elevation). Sites within the meadow domain, as most well-studied so far, are relatively insensitive to Holocene paleoenvironmental changes. [Copyright &y& Elsevier]

This work aims to estimate the potential effects of the global warming projected for the twenty-first century on the biodiversity of a remote and pristine region of the Neotropics called Pantepui. Habitat loss and fragmentation by upward migration of bioclimatic conditions is analyzed using Species-Area Relationships (SAR) and Altitudinal Range Displacement (ARD) analysis. The ARD is a tool that uses the present-day lapse rate to estimate the upward migration of the species based on the global warming predicted by the IPCC. The results show that around 80% of the vascular flora, ca. 1,700 species of which up to 400 would be Pantepui endemics, are threatened of extinction. These estimates should be considered preliminary, but the danger is real. Therefore, suitable conservation or mitigation strategies are needed. [ABSTRACT FROM AUTHOR]

Oceanic islands remained free of humans until relatively recent times. On contact, humans encountered pristine environments with unique ecosystems and species highly vulnerable to novel impacts. In the course of rendering an island habitable, the new settlers transformed it through fire, deforestation, hunting and introduction of pests and weeds. The result, as described for many oceanic islands globally, has been a catastrophe for biodiversity. Here we present the case of the Canary Islands, an Atlantic archipelago renowned for its exceptional biodiversity, and show that these islands have been no exception to the general rule. We review the archaeological, palaeoecological, palaeontological and ecological literature for the archipelago and discuss the ecological consequences – in particular habitat transformation and biodiversity loss – of human settlement. In contrast to previous views that prehistoric humans had only limited impacts on these islands, we show that vegetation change, increased fire, soil erosion, species introductions and extinctions follow the familiar oceanic pattern. Timing of human settlement of the Canary Islands has been controversial, with revised archaeological dates suggesting a relatively late arrival at the beginning of the Common Era, while palaeoecological and palaeontological evidence favours a presence several centuries earlier. While the matter is still not settled, we suggest that settlement sometime between 2400 and 2000 cal years BP is a possibility. • Prehistoric impact on the Canary Islands is reviewed with palaeoecological, palaeontological and archaeological evidence. • First Canarian settlers had substantial impact on the environment like other societies that colonized oceanic islands. • Palaeoenvironmental data suggests a possible earlier settlement than the recently revised archaeological dates. [ABSTRACT FROM AUTHOR]

Summary: A minuscule fraction of the Earth's paleobiological diversity is preserved in the geological record as fossils. What plant remnants have withstood taphonomic filtering, fragmentation, and alteration in their journey to become part of the fossil record provide unique information on how plants functioned in paleo‐ecosystems through their traits. Plant traits are measurable morphological, anatomical, physiological, biochemical, or phenological characteristics that potentially affect their environment and fitness. Here, we review the rich literature of paleobotany, through the lens of contemporary trait‐based ecology, to evaluate which well‐established extant plant traits hold the greatest promise for application to fossils. In particular, we focus on fossil plant functional traits, those measurable properties of leaf, stem, reproductive, or whole plant fossils that offer insights into the functioning of the plant when alive. The limitations of a trait‐based approach in paleobotany are considerable. However, in our critical assessment of over 30 extant traits we present an initial, semi‐quantitative ranking of 26 paleo‐functional traits based on taphonomic and methodological criteria on the potential of those traits to impact Earth system processes, and for that impact to be quantifiable. We demonstrate how valuable inferences on paleo‐ecosystem processes (pollination biology, herbivory), past nutrient cycles, paleobiogeography, paleo‐demography (life history), and Earth system history can be derived through the application of paleo‐functional traits to fossil plants. [ABSTRACT FROM AUTHOR]

Human‐mediated changes in island vegetation are, among others, largely caused by the introduction and establishment of non‐native species. However, data on past changes in non‐native plant species abundance that predate historical documentation and censuses are scarce. Islands are among the few places where we can track human arrival in natural systems allowing us to reveal changes in vegetation dynamics with the arrival of non‐native species. We matched fossil pollen data with botanical status information (native, non‐native), and quantified the timing, trajectories and magnitude of non‐native plant vegetational change on 29 islands over the past 5000 years. We recorded a proportional increase in pollen of non‐native plant taxa within the last 1000 years. Individual island trajectories are context‐dependent and linked to island settlement histories. Our data show that non‐native plant introductions have a longer and more dynamic history than is generally recognized, with critical implications for biodiversity baselines and invasion biology. [ABSTRACT FROM AUTHOR]

Cabo Verde remained uninhabited until 1460 CE, when European sailors founded a settlement in Santiago, and soon after in Fogo island. The degree to which different island ecosystems in Cabo Verde have been transformed by humans remains uncertain because of a scarcity of historical information and archaeological evidence. Disentangling these processes from natural ones is complicated in islands with a history of volcanic impacts and other natural hazards. In this paper, we apply microfossil (pollen, non-pollen palynomorphs and phytoliths) and sedimentological analyses (granulometry, X-ray diffraction, loss on ignition and tephrostratigraphy) to a 2-m sediment sequence deposited in a scoria cone from 4100 cal year BP (calibrated years before 1950 CE) to the present. The organic-rich basal sediments indicate that between 4100 and 2600 cal year BP the pre-settlement landscape of Fogo was an open grassland, where fire was infrequent and/or small-scale. An increase in volcanic glass deposition after 2600 cal year BP, peaking ca. 1200 cal year BP, suggests that there was a progressive activation of Fogo's volcanic activity, contemporaneous with increased fire frequency and erosion pulses, but with little impact on local grassland vegetation. While dating uncertainty is high, the first evidence of intensive local land use by early settlers was in the form of cultivation of Zea mays, abundant spores of coprophilous fungi (i.e. Sporormiella), and peaks in charcoal concentrations between 800 and 400 cal year BP. This was followed by large increases in pollen from pigeon pea (Cajanus), a diverse array of exotic trees (Cupressus, Grevillea), and invasive shrubs (Lantana). The introduction of these taxa is part of recent human effort to 'tame' this steep, dry and hazardous island by reducing erosion and providing firewood. An important outcome of these efforts, however, is a loss of fragile native biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: Long-term palaeoecological records are needed to test ecological hypotheses involving time, as short-term observations are of insufficient duration to capture natural variability. In this paper, we review the published palaeoecological evidence for the neotropical Gran Sabana (GS) region, to record the vegetation dynamics and evaluate the potential effects of natural climatic and anthropogenic (notably fire) drivers of change. The time period considered (last 13,000 years) covers major global climate changes and the arrival of humans in the region. The specific points addressed are climate–vegetation equilibrium, reversibility of vegetation changes, the origin of extant biodiversity and endemism patterns and biodiversity conservation in the face of global warming. Vegetation dynamics is reconstructed by pollen analysis and fire incidence is deduced from microscopic charcoal records. Palaeoclimatic inferences are derived from global and regional records using independent physico-chemical evidence to avoid circular reasoning. After analyzing all the long-term records available from both GS uplands and highlands, we conclude that: (1) Upland vegetation (mostly treeless savannas and savanna–forest mosaics, with occasional Mauritia palm swamps) is not in equilibrium with the dominant climates, but largely conditioned by burning practices; (2) a hypothetical natural or “original” vegetation type for these uplands has not been possible to identify due to continuous changes in both climate and human activities during the last 13,000 years; (3) at the time scale studied (millennial), the shift from forest to savanna is abrupt and irreversible due to the existence of tipping points, no matter the cause (natural or anthropogenic); (4) on the contrary, the shift from savanna to palm swamps is reversible at centennial time scales; (5) some of the reconstructed past vegetation types have no modern analogues owing to the individual species response to environmental shifts, leading to variations in community composition; (6) extant biodiversity and endemism patterns are not the result of a long history of topographical isolation, as previously proposed but, rather, the consequence of the action of climatic and palaeogeographic variations; (7) the projected global warming will likely exacerbate the expansion of upland savannas by favouring positive fire-climate feedbacks; (8) in the highlands, extinction by habitat loss will likely affect biodiversity but to a less extent that prognosticated by models based only on present-day climatic features; (9) future highland communities will likely be different to present ones due to the prevalence of individual species responses to global warming; and (10) conservation strategies at individual species level, rather than at community level, are enriched by long-term palaeoecological studies analyzed here. None of these conclusions would have been possible to derive from short-term neoecological observations. [Copyright &y& Elsevier]

Aim: The accumulation of functional diversity in communities is poorly understood. Conveniently, the general dynamic model of island biogeography (GDM) makes predictions for how such diversity might accumulate over time. In this multiscale study of land snail communities on 10 oceanic archipelagos located in various regions of the globe, we test hypotheses of community assembly in systems where islands serve as chronosequences along island ontogeny. Location: Ten volcanic archipelagos. Time period: From 23 Ma to the present. Major taxa studied: Endemic land snails. Methods: Initially, we assembled geological island characteristics of area, isolation and ontogeny for all studied islands. We then characterized island‐scale biotic variables, including the species diversity and functional diversity of snail communities. From these data, we assessed relationships between island and snail community variables as predicted by the GDM, focusing initially on the islands of the Galápagos archipelago and thereafter with a broader analysis of 10 archipelagoes. Results: As in other studies of island assemblages, in Galápagos we find a hump‐shaped curve of species richness, with depauperate snail faunas on early‐ontogeny islands, increasing species richness on mid‐ontogeny islands and low species richness on islands in late ontogeny. We find exceptionally low functional diversity on early‐ontogeny islands that increases through mid‐ontogeny, whereas late‐ontogeny islands exhibit a range of functional diversity. The analysis including all 10 archipelagos indicates a major role of archipelago‐specific factors. In both sets of analyses, functional diversity is exceptionally low on early‐ontogeny islands, and island ontogeny is a significant predictor of morphology. Main conclusions: Consistent patterns of functional diversity across island ontogeny on all examined archipelagos indicate a common role for habitat filtering, ecological opportunity and competition in a diversity of systems, leading to predictable changes in functional diversity and average morphology through island ontogeny, whereas patterns of species richness appear subject to archipelago‐specific factors. [ABSTRACT FROM AUTHOR]

Abstract: This paper shows a Holocene paleoecological reconstruction based on a peat bog sequence (El Paují, 4°28′N–61°35′W, 865m elevation) located in the transition zone between the Gran Sabana (SE Venezuela) savannas and the Amazon rainforests. Paleoecological trends are based on the analysis of pollen and pteridophyte spores, algal and animal remains, fungal spores, and charcoal particles. The whole record embraces the last ca. 8000calyr BP, and was subdivided into five pollen zones, representing the following vegetation succession: savanna/rainforest mosaic (8250–7715yr BP), dense rainforests (7715–5040yr BP), savanna/rainforest mosaic (5040–2690yr BP), secondary dry forests (2690–1440yr BP), and peat bog in an open savanna landscape (1440yr BP–present). These vegetation changes have been attributed to the action of climate and/or land use changes, as well as the corresponding synergies between them. Fire has been determinant in the landscape evolution. Based on the reconstructed fire and vegetation shifts, a changing land use pattern could have been recognized. Between the early and the mid Holocene (ca. 8.3–5.0kyr BP), land use practices seem to have been more linked to shifting agriculture in a rainforest landscape – as is usual in Amazon cultures – with medium fire incidence affecting only local forest spots or surrounding savannas. More extensive forest burning was recorded between ca. 5.0 and 2.7kyr BP, followed by land abandonment and the dominance of drier climates between 2.7 and 1.4yr BP. The modern indigenous culture, which prefers open environments and makes extensive use of fire thus preventing forest re-expansion, seem to have established during the last 1500yr. Therefore, a significant cultural replacement has been proposed for the region, leading to the present-day situation. Changing human activities have been instrumental for ecological evolution in this savanna–rainforest transitional region, as well as for the shaping of modern landscapes. [Copyright &y& Elsevier]

The article discusses the biodiversity loss, migration, and conservation of neotropical vascular plants in the Guayana Highlands threatened by global warming. It cites the findings of the study conducted by Nogué and colleagues which showed that 75-80% of species of the vascular flora are in danger of extinction. It talks on the possible migration rates of species in Guayana Highlands as a response to ongoing global warming and stresses the importance of complementing in situ conservation approaches with other methods. It states that ex situ actions must be adopted such as preserving germplasm units and construction of greenhouses as these will help maintain, revive, and improve the facilitation of natural migration.

The extinction of iconic species such as the dodo and the deforestation of Easter Island are emblematic of the transformative impact of human colonization of many oceanic islands, especially those in the tropics and subtropics. Yet, the interaction of prehistoric and colonial-era colonists with the forests and forest resources they encountered can be complex, varies between islands, and remains poorly understood. Long-term ecological records (e.g., fossil pollen) provide the means to understand these human impacts in relation to natural change and variability pre- and postcolonization. Here we analyze paleoecological archives in forested landscapes of the Canary Islands and Cabo Verde, first colonized approximately 2,400 to 2,000 and 490 y ago, respectively. We demonstrate sensitivity to regional climate change prior to human colonization, followed by divergent but gradual impacts of early human settlement. These contrast with more rapid transformation in the colonial era, associated with significant increases in anthropogenic pressures. In the Canary Islands, at least two native tree taxa became extinct and lowland thermophilous woodlands were largely converted to agricultural land, yet relictual subtropical laurel forests persisted with limited incursion of nonnative species. In Cabo Verde, in contrast, thermophilous woodlands were depleted and substituted by open landscapes and introduced woodlands. Differences between these two archipelagos reflect the changing cultural practices and societal interactions with forests and illustrate the importance of long-term data series in understanding the human footprint on island ecosystems, information that will be critically important for current and future forest restoration and conservation management practices in these two biodiversity hotspots. [ABSTRACT FROM AUTHOR]

Aim: Climate is usually regarded as the main determinant of plant species distributions. However, past human use of species for food might also have influenced distributions. We hypothesized that human‐mediated dispersal has resulted in food plants occupying more of their potential geographical range. We also hypothesized that key ecological traits could predispose a species to occupy more of its potential climatic geographical range and be selected by humans for food. Location: The Sonoran Desert of south‐western North America. Time period: Present day. Major taxa studied: Food plants. Methods: We used ethnobotanical data and data from large botanical ecoinformatics databases to estimate realized (dispersal‐ and climate‐constrained) and potential (climate‐constrained) ranges for food plants and their used and unused congeners. Results: We found that food plants fill more of their potential geographical ranges than their unused congeners. We also found that succulence and annual growth interacted with food usage to increase range filling. Main conclusions: Human food use has expanded the distribution of many plant species in the Sonoran Desert. [ABSTRACT FROM AUTHOR]

Aim: Palaeoecological data provide an essential long‐term perspective of ecological change and its drivers in oceanic islands. However, analysing the effects of multi‐scalar and potentially co‐occurring disturbances is particularly challenging in dry islands. Here, we aim to identify the ecological consequences of the integrated impacts of a regional drying trend, volcanic eruptions and human mass migrations in a spatially constrained environment—a small, dry oceanic island in Macaronesia. Location: Brava Island, Republic of Cabo Verde. Taxa: Terrestrial vegetation and fungi. Methods: We use palaeoecological analyses applied to a caldera soil profile that dates back to 9700 cal yr BP (calibrated years before the present). Analyses include pollen (vegetation history), non‐pollen palynomorphs (changes in fern and fungal communities), grain‐size distribution, loss‐on‐ignition and geochemistry (sedimentology and erosion regimes), microscopic tephra shards (volcanic ash deposition) and charcoal (fire regime). Results: A regional drying trend after c. 4000 cal yr BP caused increased erosion but had limited immediate impacts on highland grassland vegetation. The expansion of fern‐rich woody scrubland was contemporaneous with significant deposition of volcanic ash and erosion between 1800 and 650 cal yr BP. About 300 cal yr BP, exogenous plants expanded, grazing and fires increased, and there was a decrease of native vegetation cover. Main conclusions: Throughout the Holocene, highland vegetation in Brava was characterized by the presence of open landscapes dominated by herbaceous species (e.g. Poaceae, Forsskaolea), with some presence of woody native taxa (e.g. Ficus, Dodonaea). A regional drying trend was a driver of erosion since the Mid Holocene but did not have an immediate influence on highland vegetation. Tephra deposition is a possible driver of vegetation change. Inter‐island mass migration after volcanic events in Fogo Island c. 1680 CE potentially triggered land use change and intensification, causing a reduction of native vegetation in Brava. [ABSTRACT FROM AUTHOR]

Aim: Biogeographical regions (realms) reflect patterns of co‐distributed species (biotas) across space. Their boundaries are set by dispersal barriers and difficulties of establishment in new locations. We extend new methods to assess these two contributions by quantifying the degree to which realms intergrade across geographical space and the contributions of individual species to the delineation of those realms. As our example, we focus on Wallace's Line, the most enigmatic partitioning of the world's faunas, where climate is thought to have little effect and the majority of dispersal barriers are short water gaps. Location: Indo‐Pacific. Time period: Present day. Major taxa studied: Birds and mammals. Methods: Terrestrial bird and mammal assemblages were established in 1‐degree map cells using range maps. Assemblage structure was modelled using latent Dirichlet allocation, a continuous clustering method that simultaneously establishes the likely partitioning of species into biotas and the contribution of biotas to each map cell. Phylogenetic trees were used to assess the contribution of deep historical processes. Spatial segregation between biotas was evaluated across time and space in comparison with numerous hard realm boundaries drawn by various workers. Results: We demonstrate that the strong turnover between biotas coincides with the north‐western extent of the region not connected to the mainland during the Pleistocene, although the Philippines contains mixed contributions. At deeper taxonomic levels, Sulawesi and the Philippines shift to primarily Asian affinities, resulting from transgressions of a few Asian‐derived lineages across the line. The partitioning of biotas sometimes produces fragmented regions that reflect habitat. Differences in partitions between birds and mammals reflect differences in dispersal ability. Main conclusions: Permanent water barriers have selected for a dispersive archipelago fauna, excluded by an incumbent continental fauna on the Sunda shelf. Deep history, such as plate movements, is relatively unimportant in setting boundaries. The analysis implies a temporally dynamic interaction between a species' intrinsic dispersal ability, physiographic barriers, and recent climate change in the genesis of Earth's biotas. [ABSTRACT FROM AUTHOR]

Aim: Long‐term ecological data provide a stepped frame of island ecosystem transformation after successive waves of human colonization, essential to determine conservation and management baselines. However, the timing and ecological impact of initial human settlement on many islands is still poorly known. Here, we report analyses from a 4800‐year sedimentary sequence from Gran Canaria (Canary Islands), with the goal of disentangling forest responses to natural fire from early human pressure on the island. Location: La Calderilla, a volcanic maar caldera at 1,770 m a.s.l. on Gran Canaria. Taxon: Plants and fungi. Methods: A core from the caldera infill was analysed for sediment properties, pollen, micro‐ and macrocharcoal, with radiocarbon and biochronology dating. Fossil data were statistically zoned and interpreted with the help of cross‐correlation and ordination analyses. Surface samples and a pollen–vegetation training set were used as modern analogues for vegetation reconstruction. Results: Before human settlement (4,800–2,000 cal. yr bp), pine (Pinus canariensis) pollen dominated. Extensive dry pine forests characterized the highlands, although with temporary declining phases, followed by prompt (sub‐centennial scale) recovery. Towards 2,280 cal. yr bp there was a shift to open vegetation, marked by an increase in coprophilous spores. Coincidental with independent evidence of human settlement in the pine belt (2,000–470 cal. yr bp) there was a decline of pine and a peak in charcoal. Following historic settlement (470–0 cal. yr bp), pollen producers from anthropogenic habitats, secondary vegetation and coprophilous fungi increased in abundance, reflecting higher pressure of animal husbandry and farming. Modern moss polsters reflect extensive reforestation since 1950 ce (Common Era). Main conclusions: From 4,800 cal. yr bp, the pristine vegetation covering the Gran Canaria highlands was a mosaic of dry pine forests and open vegetation. The pine forests sustained intense fires, which may well have promoted habitat diversity. Human interference was initiated around 2,280 cal. yr bp probably by recurrent cultural firing and animal husbandry, triggering a steady trend of forest withdrawal and expansion of grasses and scrubs, until the final disappearance of the pine forest locally in the 20th century. Grasslands were found to be of ancient cultural origin in the summit areas of Gran Canaria, although they underwent an expansion after the Castilian Conquest. [ABSTRACT FROM AUTHOR]

Aim: Knowledge of the drivers of ecosystem changes in the past is key to understanding present ecosystem responses to changes in climate, fire regimes and anthropogenic impacts. Northern Hemisphere‐focussed studies suggest that climate and human activities drove turnover during the Holocene in temperate ecosystems. Various drivers have been invoked to explain changes in Southern Hemisphere temperate vegetation, but the region lacks a quantitative assessment of these drivers. To better understand the regional drivers of past diversity, we present a quantitative meta‐analysis study of turnover and richness during the lateglacial and Holocene in Australian temperate ecosystems. Location: South‐east Australia (Tasmania, Bass Strait, SE mainland). Methods: We conducted a meta‐analysis study of 24 fossil pollen records across south‐east Australian temperate ecosystems, applying an empirical turnover threshold to fossil records to identify periods of major turnover for the first time in Australia. We tested pollen richness as a proxy for vegetation richness to estimate past richness and applied this to fossil pollen data. The resulting reconstructions were compared to independent records of climate, sea‐level change and fire through generalized linear modelling. Results and conclusion: Our results show changes in available moisture and sea level drove turnover and richness in most parts of SE Australia in the past, explaining up to c. 97% deviance. However, fire mainly drove turnover in Bass Strait. Our richness reconstructions also support the intermediate disturbance hypothesis, suggesting that high biodiversity was partially maintained by anthropogenic‐managed fire regimes. While temperature change is considered key to Northern Hemisphere palaeodiversity, past turnover and richness in Southern Hemisphere temperate ecosystems responded mainly to moisture availability and sea‐level change (considering its role in modulating regional oceanic climate). [ABSTRACT FROM AUTHOR]

São Tomé (Gulf of Guinea, Central Africa) is a 854 km2 tropical island that had a pivotal role in early European colonial expansion through the Atlantic between the 15th and 16th centuries. Historical sources suggest that native vegetation has been heavily impacted since human arrival (1470 CE) due to monoculture economies and the introduction of mammals and plants, some of which now have established wild populations. The Afromontane forest of São Tomé, located above 800 m.a.sl., is particularly rich in endemic plant species and has remained relatively unaffected by direct human impacts. Here, we explore how environmental change influenced this forest through the study of a sedimentary sequence from the volcanic crater of Lagoa Amélia (1340 m a.s.l.), a palustrine system located at the boundary between submontane (800–1400 m a.s.l.) and mist forest (above 1400 m a.s.l.). We used fossil pollen, non-pollen palynomorphs, sedimentology and charcoal to determine forest dynamics from the Late Pleistocene to the present. From 14,000 to 12,500 cal yr BP the forest was dominated by taxa from higher altitudes, adapted to cooler and drier climates (e.g. Afrocarpus mannii trees and Psychotria nubicola). After 12,500 cal yr BP, a potential uphill migration was identified by an increase in taxa like the trees Symphonia globulifera and Craterispermum cerinanthum. From 11,200 cal yr BP through the rest of the Holocene taxa from lower altitudes became dominant (e.g. Prunus africana , Polyscia s, and Sabicea) , except at c. 8500 cal yr BP when rapid cooling led to forest opening. Charcoal showed that fires were frequent during the Late Pleistocene (14,000 to 11,200 cal yr BP), becoming rare during the Holocene until anthropogenic fires started at c. 220 cal yr BP. Other recent anthropogenic impacts detected in Lagoa Amélia included the appearance of pollen of introduced plant species (e.g., Cestrum), and the increase in pollen of economically important species (Elaeis guineensis , Zea mays) and in fungal spores related to introduced herbivores. Our results reveal that climate changed the altitudinal distribution of the Afromontane forest in São Tomé during the Late Pleistocene, as observed on the African continent, and that this ecosystem was also strongly impacted by human arrival, through fire, farming, and introduced species. • We assess how climatic changes and humans influenced Afromontane forest around the Lagoa Amélia volcanic crater. • We document Late Pleistocene uphill migration of forest taxa and the occurrence of natural forest fires • During the Holocene taxa from lower altitudes became dominant and fires became rare. • We detect recent human impacts (200 cal yr BP-present) through fire and the introduction of plant and animals. • Comparison with mainland records suggests that island Afromontane forest long-term shifts were analogue to continental ones. [ABSTRACT FROM AUTHOR]

Cabo Verde was the first tropical archipelago colonized by Europeans. Historians have suggested that the first colonizers initiated archipelago-wide ecosystem degradation, loss of vegetation cover, and erosion. However, the human–environment interactions that led to the archipelago's current environmental status remain poorly understood. Here, we report the first palaeoecological study of past vegetation change and disturbance regimes for Cabo Verde. We present a 2130-yr old sediment sequence from a volcanic caldera (Cova de Paúl) located at ~1200 m asl on Santo Antão Island, for which we analyzed fossil pollen, non-pollen palynomorphs (NPPs), charcoal, silica bodies, and grain size distribution. Our analyses do not show evidence of the presence of temperate, tropical or subtropical forests growing on the summits of Santo Antão in pre-human times. The pollen record shows that scrubland and grasslands dominated the highlands and underwent compositional changes ca. 1850 and 1300 cal yr BP. These shifts overlap with erosion phases and are linked to intensified seasonality. Steady rates of sedimentation marked the period 1230 to ca. 350 cal yr BP, but an increase in charcoal concentrations indicate a drying phase. Increases in regional and local fire, peaks of coprophilous fungi and the presence of New World crop pollen (Zea mays) are interpreted as the onset of Portuguese settlement of the highlands after 450 BP. Sustained erosion between ca. 350 and 100 cal yr BP indicate soil degradation, and the pollen record shows the increase in introduced herbaceous taxa (Rosaceae, Centaurea , Verbenaceae) and exotic tree taxa (e.g. Pinus), while shifting abundances of coprophilous fungi indicate changes in land-use. The record shows stabilization of soils in the last century due to recent afforestation of the highlands. Further palaeoecological studies have the potential to provide further detail of the long-term dynamics of Cabo Verde ecosystems and to inform conservation initiatives. • We present the first palaeoecological record from Cabo Verde: a 2130-yr sediment sequence from Santo Antão Island. • We found no signs of ancient woodlands in one of the highest and most humid islands of Cabo Verde. • Pre-human landscapes experienced erosion phases linked to intensified monsoonal activity and increased seasonality. • Human transformation of local landscapes led to compound perturbations in the ecosystems and erosion of local soils. [ABSTRACT FROM AUTHOR]

The coupling between community composition and climate change spans a gradient from no lags to strong lags. The no-lag hypothesis is the foundation of many ecophysiological models, correlative species distribution modelling and climate reconstruction approaches. Simple lag hypotheses have become prominent in disequilibrium ecology, proposing that communities track climate change following a fixed function or with a time delay. However, more complex dynamics are possible and may lead to memory effects and alternate unstable states. We develop graphical and analytic methods for assessing these scenarios and show that these dynamics can appear in even simple models. The overall implications are that (1) complex community dynamics may be common and (2) detailed knowledge of past climate change and community states will often be necessary yet sometimes insufficient to make predictions of a community's future state. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses the bureaucratic challenges of conducting biodiversity research in the Guayana Highlands of Venezuela.

Abstract: The southern Gran Sabana (SE Venezuela) holds a particular type of neotropical savanna characterized by the local occurrence of morichales (Mauritia palm swamps), in a climate apparently more suitable for rain forests. We present a paleoecological analysis of the last millennia of Lake Chonita (4°39′N–61°0′W, 884m elevation), based on biological and physico-chemical proxies. Savannas dominated the region during the last millennia, but a significant vegetation replacement occurred in recent times. The site was covered by a treeless savanna with nearby rainforests from 3640 to 2180cal yr BP. Water levels were higher than today until about 2800cal yr BP. Forests retreated since about 2180cal yr BP onwards, likely influenced by a higher fire incidence that facilitated a dramatic expansion of morichales. The simultaneous appearance of charcoal particles and Mauritia pollen around 2000cal yr BP supports the potential pyrophilous nature of this palm and the importance of fire for its recent expansion. The whole picture suggests human settlements similar to today – in which fire is an essential element – since around 2000yr ago. Therefore, present-day southern Gran Sabana landscapes seem to have been the result of the synergy between biogeographical, climatic and anthropogenic factors, mostly fire. [Copyright &y& Elsevier]

Identifying the impacts of anthropogenic fires on biodiversity is imperative for human-influenced tropical rainforests because: i) these ecosystems have been transformed by human-induced fires for millennia; and ii) their effective management is essential for protecting the world's terrestrial biodiversity in the face of global environmental change. While several short-term studies elucidate the impacts of fires on local plant diversity, how plant diversity responds to fire regimes over long timescales (>100 years) is a significant knowledge gap, posing substantial impediment to evidence-based management of tropical social-ecological systems. Using wet evergreen forests of the Western Ghats of India as a model system, we discuss the synergistic effects of anthropogenic fires and enhanced aridity on tropical plant diversity over the past 4000 years by examining fossil pollen-based diversity indices (e.g., pollen richness and evenness, and temporal β-diversity), past fire management, the intervals of enhanced aridity due to reduced monsoon rainfall and land use history. By developing a historical perspective, our aim is to provide region-specific management information for biodiversity conservation in the Western Ghats. We observe that the agroforestry landscape switches between periods of no fires (4000-1800 yr BP, and 1400-400 yr BP) and fires (1800-1400 yr BP, and 400-0 yr BP), with both fire periods concomitant with intervals of enhanced aridity. We find synergistic impacts of anthropogenic fires and aridity on plant diversity uneven across time, pointing towards varied land management strategies implemented by the contemporary societies. For example, during 1800–1400 yr BP, diversity reduced in conjunction with a significant decrease in the canopy cover related to sustained use of fires, possibly linked to large-scale intensification of agriculture. On the contrary, the substantially reduced fires during 400–0 yr BP may be associated with the emergence of sacred forest groves, a cultural practice supporting the maintenance of plant diversity. Overall, notwithstanding apparent changes in fires, aridity, and land use over the past 4000 years, present-day plant diversity in the Western Ghats agroforestry landscape falls within the range of historical variability. Importantly, we find a strong correlation between plant diversity and canopy cover, emphasising the crucial role of maintenance of trees in the landscape for biodiversity conservation. Systematic tree management in tropical social-ecological systems is vital for livelihoods of billions of people, who depend on forested landscapes. In this context, we argue that agroforestry landscapes can deliver win-win solutions for biodiversity as well as people in the Western Ghats and wet tropics at large. • Effective fire and ecological management in tropics require a long-term perspective. • In the Western Ghats, fires-plant diversity relationship is non-linear across time. • Fire management in the Western Ghats demands an inclusive and integrative approach. • Tree cover is the vital determinant of sustaining plant diversity in wet tropics. • Agroforestry is a win-win solution for tropical biodiversity and peoples' livelihoods. [ABSTRACT FROM AUTHOR]

Tropical dry islands are currently facing major challenges derived from anthropogenic and climatic pressures. However, their trajectories of environmental change, which could provide relevant information applicable to biodiversity conservation, remain understudied. This is mainly due to poor micro-fossil preservation and irregular sediment deposition. Multi-proxy palaeoecological analyses spanning decades to 1000s of years can add perspective as to how vegetation, fungal communities, and the fauna responded to previous natural and anthropogenic disturbances. In São Nicolau, Cabo Verde, we used palaeoecological methods to analyse a highland soil profile (1000 m asl) dated to 5900 cal yr BP. We analysed how vegetation (abundances in pollen of native and introduced species, and leaf wax n -alkanes), ferns and fungal communities (abundance of non-pollen palynomorphs) varied over time in relation to fire (charcoal concentration) and erosion regimes (grain sizes and elemental composition). Between 5000 and 400 cal yr BP the highlands held native woody taxa such as Euphorbia tuckeyana , Dracaena draco subsp. caboverdeana , and Ficus , taxa that can be used for future reforestation programmes. From 400 cal yr BP to the present day, replacement of native taxa by introduced and cultivated taxa (Pinus , Eucalyptus , Asystasia , Opuntia) has occurred. Vegetation burning and grazing caused loss of vegetation and erosion, acting as conjoined drivers of scrubland degradation. This dataset helps to set historically contextualised restoration goals such as the re-introduction of native species, monitoring of recently introduced species and control of free grazing. This can serve as a model system for the conservation of tropical dry islands' biodiversity. Unlabelled Image • Palaeoecological analyses reveal 5900-yr of ecological change in São Nicolau. • Fern-rich endemic-dominated scrublands present (5000–410 cal yr BP) even after fire. • Introduced grazers and vegetation burning caused erosion and landscape opening. • Results are used to set historically-contextualised conservation/restoration goals. • Methods are applicable in other dry tropical islands in Cabo Verde and beyond. [ABSTRACT FROM AUTHOR]