Bushfires contribute to environmental pollution in the form of Particulate Matter (PM). PM with an aerodynamic diameter of ≤ 2.5 μm (PM2.5) is relevant to individuals with chronic respiratory diseases such as asthma. These particles tend to enter the bloodstream and activate inflammatory processes, leading to asthma exacerbation. This study examines this environmental-health relationship in the context of the 2019-2020 "Black Summer" bushfires in New South Wales (NSW) and the Australian Capital Territory (ACT) regions of Australia. Weekly measurements of emergency department (ED) presentations for asthma from 1 September 2019 to 29 February 2020 were collected and compared to weekly averages of PM2.5, meteorological data, and other relevant covariables. To control for seasonal changes in ED presentations unrelated to bushfire smoke, the observed PM2.5 values and ED presentations were subtracted from corresponding values the year prior. A quasi-Poisson generalised linear model (GLM) was used to assess the impact of PM2.5 and these covariables on weekly ED presentations for asthma. The model explained approximately 33% of the variance in asthma presentations with PM2.5, minimum temperature and relative humidity being the most significant covariables. These findings provide insight into this environmental-health relationship and support public health planning for smoke-related asthma presentations.

Extensive research carried out during the last 30 years in the lowermost foothills of the Southern Pyrenees has revealed the significance of this area for studying Neanderthal lifestyle and settlement histories in the Iberian Peninsula. With a large number of cave and rock shelter sites, broad-ranging chronologies, and relatively well-known sedimentation rates and environmental conditions, this enclave continues to improve our knowledge about Neanderthal behaviour in Western Europe.Here we present the chronostratigraphic, technological, faunal, and palaeoenvironmental results from Abric Pizarro, a recently discovered site from the region. Its archaeological sequence is centred on MIS 4, a poorly known period in Neanderthal history. The application of three different dating methods (newly obtained single-grain optically stimulated luminescence and U-series fossil teeth ages, in addition to previously published thermoluminescence ages) provides an accurate chronology for a site where the exceptional preservation of faunal remains leads to significant interpretations of Neanderthal hunting abilities and adaptability. Moreover, analysis of the lithic assemblage, as well as preliminary palaeoenvironmental data, are used to provide insights into the degree to which chronocultural or palaeoenvironmental factors were responsible for some of the significant differences observed among the four archaeological units explored in Abric Pizarro to date. Our results contribute to discussion about Neanderthal resilience and their livelihood before their disappearance from the archaeological record.

Wildfires in forests globally have become more frequent and intense because of changes in climate and human management. Shrub layer fuels allow fire to spread vertically to forest canopy, creating high-intensity fires. Our research provides a deep-time perspective on shrub fuel loads in fire-prone southeastern Australia. Comparing 2833 records for vegetation cover, past climate, biomass burning, and human population size across different phases of human occupation, we demonstrated that Indigenous population expansion and cultural fire use resulted in a 50% reduction in shrub cover, from approximately 30% from the early to mid-Holocene (12 to 6 thousand years ago) to 15% during the late to mid-Holocene (6 to 1 thousand years ago). Since the start of British colonization to the present, shrub cover has increased to the highest ever recorded (mean of 35% land cover), increasing the risk of high-intensity fires.

Mercury (Hg) is a volatile metal of international concern due to its toxicity, with a large atmospheric emission and transport capacity. The biogeochemical cycle of Hg is sensitive to changes in climate, yet our understanding of the specific impact of climatic factors on the Hg cycle remains limited. Here we use a multi-proxy framework, supported by AMS C-14 dating, to interpret climatic events in South-Eastern Australia from similar to 18,000 years to 6500 years before present from the sediments of Blue Lake in Australia's alpine region. By combining Hg analysis with Antarctic temperature records and iTRACE climate model outputs, carbon-to-nitrogen ratios (C:N), macroscopic charcoal, and pollen analysis, we find Hg records within Blue Lake's sediments primarily reflect changes in the catchment as a result of a changing climate. The increase in Hg concentrations began with the onset of the Holocene, following a glacial period during which the region was predominantly rocky, relatively barren, and likely covered by ice and snow. The strong relationship between Hg and organic matter in our record indicates that soil development in the watershed post de-glaciation was a predominant driver of Hg concentration and deposition in Blue Lake. An increase in precipitation and temperature in the Holocene contributed to an increase in nutrients and organic matter, further increasing Hg concentration in Blue Lake. A primary challenge in modern Hg research, particularly in the context of climate change, involves distinguishing changes in Hg levels resulting from human activities from those driven by climatic variations. Our pre-anthropogenic data highlight the long-term interrelationships among climate dynamics, soil processes, and ecological transformations within lake catchments on the geochemical cycle of Hg. These connections should be factored into strategies aimed at mitigating Hg increases in lake sediments resulting from global warming.

Background The global human footprint has fundamentally altered wildfire regimes, creating serious consequences for human health, biodiversity, and climate. However, it remains difficult to project how long-term interactions among land use, management, and climate change will affect fire behavior, representing a key knowledge gap for sustainable management. We used expert assessment to combine opinions about past and future fire regimes from 99 wildfire researchers. We asked for quantitative and qualitative assessments of the frequency, type, and implications of fire regime change from the beginning of the Holocene through the year 2300. Results Respondents indicated some direct human influence on wildfire since at least ~ 12,000 years BP, though natural climate variability remained the dominant driver of fire regime change until around 5,000 years BP, for most study regions. Responses suggested a ten-fold increase in the frequency of fire regime change during the last 250 years compared with the rest of the Holocene, corresponding first with the intensification and extensification of land use and later with anthropogenic climate change. Looking to the future, fire regimes were predicted to intensify, with increases in frequency, severity, and size in all biomes except grassland ecosystems. Fire regimes showed different climate sensitivities across biomes, but the likelihood of fire regime change increased with higher warming scenarios for all biomes. Biodiversity, carbon storage, and other ecosystem services were predicted to decrease for most biomes under higher emission scenarios. We present recommendations for adaptation and mitigation under emerging fire regimes, while recognizing that management options are constrained under higher emission scenarios. Conclusion The influence of humans on wildfire regimes has increased over the last two centuries. The perspective gained from past fires should be considered in land and fire management strategies, but novel fire behavior is likely given the unprecedented human disruption of plant communities, climate, and other factors. Future fire regimes are likely to degrade key ecosystem services, unless climate change is aggressively mitigated. Expert assessment complements empirical data and modeling, providing a broader perspective of fire science to inform decision making and future research priorities.

The aim of this study is to provide the drivers of long-term fire dynamics in various regions of Sub-Saharan Africa using a synthesis of updated sedimentary charcoal records, from 25,000 years ago to the present. We used the charcoal data currently available in the Global Paleofire Database, updated with the most recent published charcoal data, to reconstruct past biomass burning across the continent. We analyzed standardized charcoal data grouped by region (central Africa, eastern Africa, southern Africa, and Indian Ocean) and by vegetation type (forest, savanna, and shrubland). Within this framework, we found that quality data were lacking to reconstruct a robust trend in biomass burning before 5000 years at the continental scale. This large spatial scale was indeed masking regional peculiarities. Our results suggest that past changes in biomass burning were nuanced and cannot be simply attributed to either climate- or humans, and that they varied from each sub-regions and vegetation type history. In central Africa, biomass burning increased after the end of the African Humid Period and the first wave of Bantu-speaking people migration, whereas in East Africa and the Indian Ocean islands, it seems that human population growth was the main driver of fire activity. In South Africa, reduced rainfall seemed to offset fire activity due to population growth by reducing potentially flammable biomass. While the diversity of methodological techniques used to produce charcoal quantification made comparisons difficult, regional patterns still emerged from these data. This synthesis thus highlights the need to increase the number of sites with charcoal data and to harmonize charcoal extraction and quantification methods across Africa to improve regional to continental assessments of fire histories.

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This Element addresses a burning question – how can archaeologists best identify and interpret cultural burning, the controlled use of fire by people to shape and curate their physical and social landscapes? This Element describes what cultural burning is and presents current methods by which it can be identified in historical and archaeological records, applying internationally relevant methods to Australian landscapes. It clarifies how the transdisciplinary study of cultural burning by Quaternary scientists, historians, archaeologists and Indigenous community members is informing interpretations of cultural practices, ecological change, land use and the making of place. This title is also available as Open Access on Cambridge Core.

This is a reply to the comments of Penna [...]

Remote islands harbour many endemic species and unique ecosystems. They are also some of the world's most human-impacted systems. It is essential to understand how island species and ecosystems behaved prior to major anthropogenic disruption as a basis for their conservation. This research aims to reconstruct the original, precolonial biodiversity of a remote oceanic island to understand the scale of past extinctions, vegetation changes and biodiversity knowledge gaps. We studied fossil remains from the North Atlantic island of Corvo (Azores), including pollen, charcoal, plant macrofossils, diatoms and geochemistry of wetland sediments from the central crater of the island, Caldeira similar to o. A comprehensive list of current vascular plant species was compiled, along with a translation table comparing fossilized pollen to plant species and a framework for identifying extinctions and misclassifications. Pollen and macrofossils provide evidence for eight local extinctions from the island's flora and show that four species listed as 'introduced' are native. Up to 23 % of the pollen taxa represent extinct/misclassified species. Corvo's past environment was dynamic, shifting from glacial -era open vegetation to various Holocene forest communities, then almost completely deforested by fires, erosion and grazing following Portuguese colonisation. Historical human impacts explain high ecological turnover, several unrecorded extinctions and the present-day abundance of vegetation types like Sphagnum blanket mire. We use Corvo as a case study on how fossil inventories can address the Wallacean and Hookerian biodiversity knowledge gaps on remote islands. Accurate baselines allow stakeholders to make informed conservation decisions using limited financial and human resources, particularly on islands where profound anthropogenic disruption occurred before comprehensive ecological research.

Neste artigo pretende-se apresentar o jogo de tabuleiro A aventura para o conhecimento como uma ferramenta facilitadora do processo de ensino-aprendizagem. Este foi criado para auxiliar a disseminação e comunicação de ciência no âmbito de um projeto de investigação internacional e interdisciplinar que estuda as alterações ambientais que ocorreram ao longo dos últimos 7500 anos na costa sudeste de Moçambique.

The effects of climate change on long-term mercury (Hg) cycling are still not well understood, as climate changes are usually gradual and can only be assessed using high-resolution archives. Our study site (a small, lowland tectonic lake in Sulawesi, Indonesia) provides a unique opportunity to further understanding of Hg cycling in the Southeast Asian (SEA) tropics during the transition from the Pleistocene to the Holocene, a period of significant climate variability. We present a high-resolution record of Late Glacial and Holocene Hg deposition within the sediments of tropical Lake Lantoa, Sulawesi. Using a multi-proxy framework (including pollen, charcoal, carbon:nitrogen ratio and high-resolution geochemistry records) we investigate the response of Hg accumulation rates (HgAR) in sediments to shifts in climate between ∼16,488 and 538 cal BP. This period encompasses the Bølling-Allerød (BA) warming, Younger Dryas (YD) cooling and Holocene warming events, providing new insights into the effects of global climatic transitions on HgAR in SEA sediments. The Pleistocene Termination had the highest HgAR and substantial variability (µ = 11.32, 5.38–33.91 μg m−2 yr−1), when drier conditions and high charcoal accumulation rates suggest that fire activity was the main source of Hg to the lake. The Holocene Transition was marked by a decrease in HgAR (µ = 8, 3.50–18.84 μg m−2 yr−1) as humid conditions precluded forest burning, followed by high HgAR (µ = 11.35, 3.30–158.32 μg m−2 yr−1) in the Early Holocene. Mercury accumulation rate in the Late Holocene (µ = 3.80, 1,67–43.65 μg m−2 yr−1) was the lowest in the Lake Lantoa record, marked by the lowest fire events and a stable catchment. An increase in carbon:nitrogen ratios during the Late Holocene, coupled with a decrease in HgAR, suggests that the establishment of lowland forest resulted in suppressed Hg erosion/leaching. Our results demonstrate that forest fires, vegetation change and volcanism are important drivers of Hg inputs to Lake Lantoa, a relationship which is strongly mediated by climate and lake-catchment dynamics.

Abstract The Iberian Peninsula is a significant region for studying the Middle to Upper Palaeolithic Transition (MUPT). Broadly speaking, this transition refers to the period when anatomically modern humans (Homo sapiens, AMH) first appeared in the archaeological record of Palaeolithic Europe and the later extinction of Neanderthals in Europe. The Iberian Peninsula is a significant region for studying the causes of the replacement of Neanderthals by Anatomically Modern Humans, as it was one of the last places where these Neanderthals lived. Many theories have been proposed to explain the disappearance of Neanderthals, ranging from competition with Homo sapiens to environmental factors, such as climate change. Here we explore the relationship of the replacement of the Neanderthal by AMH populations and its relationship with climate change, by providing an overview of the archaeological and climate records in Iberian Peninsula during the Middle to Upper Palaeolithic transition (MUPT). Through the use of a relational database (combining archaeological information and radiocarbon dates), Summed Probability of Calibrated Radiocarbon Dates (SPCD), paleoecological records, GIS and Spatial modelling, this chapter examines the timing of the distribution of last Neanderthals and the entrance and distribution of AMH and its populational fluctuations in Iberian periods of climate change.

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.

"Fires in GunaiKurnai Country: Landscape Fires and their Impacts on Aboriginal Cultural Heritage Places and Artefacts in Southeastern Australia." Australian Archaeology, ahead-of-print(ahead-of-print), pp. 1–2

The Black Summer bushfires (2019-2020) cost the Australian economy over 100 billion dollars and burnt a total of 18 million hectares. In just one season, around 20% of Australia's Eucalyptus forests burnt down and billions of animals perished. Recent catastrophic fires in Australia and North America have made scientists and policymakers question how the disruption of First Nations' burning practices has impacted fuel loads. For instance, we have learnt from modern Australian Indigenous communities, historical literature, and art works that Indigenous peoples have used cultural burning to rejuvenate patches of land and preserve open vegetation for hunting and cultural purposes. The advent of British invasion brought a change in the type of fire regimes and landscape management across much of the continent, which may have led to an increase in flammable fuels in forest settings. However, the actual degree of land-cover modification by early settlers has only been often debated in the academic literature and within management stakeholders.The quantification of past land cover is needed to address such debates. Pollen is the key proxy to track past vegetation changes, but pollen spectra suffer from some important biases e.g. taphonomy, pollen productivity, dispersal capability. Estimating past vegetation cover from sedimentary pollen composition requires to correct for productivity and dispersal biases using empirical-based models of the pollen-vegetation relationship. Such models for quantitative vegetation reconstruction (e.g. REVEALS) have yet been mostly applied in the Northern Hemisphere in the last 15 years - here we present recent applications of this methodology from Australia. We show the quantification of land cover changes through pre- and post- British invasion on multiple records (n=51) across the southeastern Australian region. This represents the first regional application of REVEALS within the Australian continent.We provide the first empirical evidence that the regional landscape before British invasion was a cultural landscape with limited tree cover as it was maintained by Indigenous Australians through cultural burning. Our findings suggest that the removal of Indigenous vegetation management has altered woodland fuel structure and that much of the region was predominantly open before colonial invasion. The post-colonial land modification has resonance in wildfire occurrence and management under the pressing challenges posed by climate change.

The above article, published online on 29 January 2022 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal’s Editor in Chief Steve Long, and John Wiley & Sons Ltd. The retraction has been agreed because of an error the authors of the paper detected in the R code they used in running the rates of change (RoC) analysis. It was discovered after publication that the R code used in the analysis only picked a single pollen site for each rainforest region, despite the authors´ intention to reconstruct RoC for each rainforest region based on multiple pollen sites. Accordingly, the conclusions of this manuscript are based only on the RoC of single pollen records from each rainforest region, and so are insufficient for a robust and accurate analysis of RoC for each rainforest.