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Rivers of tropical islands formed by volcanic eruptions experience unpredictable and heavy rainfall and are characterised by irregular topography. During the 2019 and 2020 low-water season, we investigated the responses of benthic macroinvertebrate assemblages to variations in local environmental conditions in four rivers located in areas of different rainfall intensity. We found that changes in local environmental conditions associated with lower rainfall intensity reduced abundance and taxonomic richness and modified taxonomic composition but did not impact the balance of functional feeding groups of macroinvertebrate communities amongst streams, except for piercer herbivores. Heterotrophy associated with substrate instability and autotrophy with a more stable substrate co-occurred in semi-arid climate rivers. In contrast, a change from heterotrophy upstream to autotrophy and substrate stability downstream was apparent in the two humid rivers studied. Surrogates of stream ecosystem function revealed a very low ratio of coarse to fine particulate organic matter related to the quasi-absence of shredders in these streams and suggested a low allochthonous input contribution, which could be the result of the 5% decline in forest cover over the two past decades. [ABSTRACT FROM AUTHOR]

The cause of Paget's disease of bone (PDB) is unknown. It emerged as a distinct entity in Britain in the late nineteenth century when it was prevalent, and florid presentation not uncommon. Epidemiological surveys in the 1970s showed that Britain had a substantially higher prevalence of PDB than any other country. Studies in the late twentieth and early twenty-first centuries have documented an unexplained change in presentation, with a greatly reduced prevalence and less severe disease than formerly. The emergence of PDB in Britain coincided with rapid industrialization which, in turn, was driven by the use of coal for energy. In the home, bituminous coal was customarily burnt on an open hearth for heating. Using data on coal production, population size, and estimates of domestic use, the estimated exposure to domestic coal burning rose threefold in Britain during the nineteenth century and began to fall after 1900. This pattern fits well with the decline in PDB documented from death certification and prevalence surveys. Colonists moving from Britain to North America, Australia and New Zealand established coal mines and also used coal for domestic heating. PDB was found in these settler populations, but was largely absent from people indigenous to these lands. In all parts of the world PDB prevalence has fallen as the burning of coal in open hearths for domestic heating has reduced. The nature of the putative factor in coal that could initiate PDB is unknown, but possible candidates include both organic and inorganic constituents of bituminous coal. [ABSTRACT FROM AUTHOR]

Palo Laziale Wood is a relatively small biotope (129 ha) situated along the coast of the Metropolitan Area of Rome, Lazio region, Italy. Despite being one of the region's remaining patches of an ancient oak floodplain broad-leaved forest, it conserves numerous priority habitats and species of high conservation interest. The vegetation consists mainly of Turkey oak stands with small temporary ponds and flooded meadows. The forest underwent a dieback in 2003, triggered by a significantly hot and dry summer. In 2018, an ecological restoration project (LIFE PRIMED LIFE17 NAT/GR/000511) was initiated to restore Palo Laziale's ecosystems. This paper presents the methodological approach employed to assess the vegetation ecology of a degraded forest ecosystem. Such an investigation was a key component of the Adaptative Restoration Plan of the Project. It provided the baseline necessary for designing and calibrating the planned direct conservation actions on the target habitat types (91M0: Pannonian-Balkanic turkey oak-sessile oak forests, 3170*: Mediterranean temporary ponds, 5230*: Arborescent matorral with Laurus nobilis, etc.) and establishing reference values to enable long-term monitoring. Plant taxa comparison from 1 ha square-grid sampling and multivariate analyses were carried out to group species and identify environmental and Ellenberg-based drivers. Six ecologically distinct units were found, eventually confirming the distinctive ecological heterogeneity of Mediterranean ecosystems. Amongst these, the hygrophilous vegetation has resulted to be the one mainly affected by the dieback outbreak. Due to the high heterogeneity, introduced by the massive tree mortality, the method of regular 1 ha squares turned out to be a reliable alternative to random vegetation sampling plots (e.g., phytosociological relevés) to disentangle ecological patterns of fragmented and disturbed habitats. [ABSTRACT FROM AUTHOR]

Coastal forests on sandy beaches in Japan are mainly established by Pinus thunbergii Parl.. These forests prevent and mitigate disasters such as wind, sand, tide, and tsunami. But Pinus thunbergii die-off is progressing nationwide in Japan and the function of coastal forests is declining. Therefore, a multi-tiered forest has been proposed composed of Pinus thunbergii and broadleaf trees instead of Pinus thunbergii trees. However, few studies have quantitatively evaluated the shade-tolerance characteristics of the broadleaf trees that comprise these forests. To this end, we measured chlorophyll levels (SPAD value) in eight representative evergreen broadleaf tree species inhabiting coastal areas in Japan and evaluated their shade-tolerance. [ABSTRACT FROM AUTHOR]

Background: Dehydration of plant tissues caused by water stress affects the dynamics of the lateral cambium, the rate of cell division and differentiation in cell lumen size, wall thickness and wall chemical properties. Based on evidence that ongoing climate change projects longer and more intense water stress conditions, forest dynamics and decline are predicted to be affected by increases in drought intensity and frequency. To verify the interaction of these phenomena, we described the modifications in the anatomy and mineral contents of annual growth rings of Araucaria araucana seedlings subjected to water stress treatments, using X-ray densitometry and X-ray fluorescence techniques. Results: Severe water stress conditions during the growing period produced narrower tree rings, with reduced cell lumen size (5–7 µm) and higher tracheid reinforcement factor values, but with lower wood density. Plants subjected to moderate water stress generated intra-annual density fluctuations coinciding with periods of decreased soil moisture. Under the precept that the essential nutrients play a relevant role in the functioning of trees, we found evidence of element allocation and concentration in response to drought. Calcium and phosphorus concentration increased significantly as stress becomes more severe, but with small differences between early- and latewood. On the contrary, potassium and sulfur presented lower values in the most stressed plants, and manganese had the lowest values only for moderate water stress. Finally, S/Ca and K/Ca molar ratios decreased, while Ca/Mn increased as stress becomes more severe. Conclusions: Our findings suggested that A. araucana seedlings invested resources aimed at increasing structural components of the cell wall to prevent cavitation. This would maintain metabolism and cell growth even in unfavorable environmental conditions. Furthermore, the imbalance of manganese and calcium and their consequent ratio (Ca/Mn) could be linked to early adaptive signals to avoid dieback. [ABSTRACT FROM AUTHOR]

Climate change has increased the susceptibility of forest ecosystems, resulting in escalated forest decline globally. As one of the largest forest biomasses in the Northern Hemisphere, the Eurasian boreal forests are subjected to frequent drought, windthrow, and high-temperature disturbances. Over the last century, bark beetle outbreaks have emerged as a major biotic threat to these forests, resulting in extensive tree mortality. Despite implementing various management strategies to mitigate the bark beetle populations and reduce tree mortality, none have been effective. Moreover, altered disturbance regimes due to changing climate have facilitated the success of bark beetle attacks with shorter and multivoltine life cycles, consequently inciting more frequent bark beetle-caused tree mortality. This review explores bark beetle population dynamics in the context of climate change, forest stand dynamics, and various forest management strategies. Additionally, it examines recent advancements like remote sensing and canine detection of infested trees and focuses on cutting-edge molecular approaches including RNAi-nanoparticle complexes, RNAi-symbiotic microbes, sterile insect technique, and CRISPR/Cas9-based methods. These diverse novel strategies have the potential to effectively address the challenges associated with managing bark beetles and improving forest health in response to the changing climate. [ABSTRACT FROM AUTHOR]

Despite three decades of policies discouraging biomass-based cooking in Africa, demand for fuelwood continues to rise. Several studies focus on household energy use, but few consider the role of commercial premises such as bakeries in deforestation, despite growing demand for bread. This study examines bread production by commercial bakeries in forest communities in Nigeria, investigating (a) the energy sources used, (b) the changes to forests and (c) the factors that could enable bakeries to transition towards clean energy. Mixed methods were used including questionnaire surveys, land use change mapping and assessments of forest plots. Questionnaires with 21 bakeries in two northern Nigerian states (Kaduna, Nasarawa) and Abuja Federal Capital Territory suggest that they depend heavily on fuelwood, collected directly from the forest, or purchased from (largely female) suppliers, retailers or wholesalers. Bakeries most commonly use Anogeissus leiocarpa mainly due to its burning quality and availability. Remote sensing data show declines in forest cover from 71% (56,157 km2) in 2000 to 49% (38,756 km2) in 2020. While all bakeries were willing to transition to more sustainable energy sources, training on alternative fuels and more energy efficient ovens is required. Policies supporting energy transition must consider all value chain actors, not just fuelwood consumers, recognising that women play a key role in fuelwood sales at the community level. Transition efforts need to be underpinned by detailed analyses of trade-offs so that measures to reduce undesirable livelihood impacts can be established, and should consider more efficient ovens as well as stoves. [ABSTRACT FROM AUTHOR]

Air pollution caused by tropospheric ozone contributes to the decline of forest ecosystems; for instance, sacred fir, Abies religiosa (Kunth) Schltdl. & Cham. forests in the peri-urban region of Mexico City. Individual trees within these forests exhibit variation in their response to ozone exposure, including the severity of visible symptoms in needles. Using RNA-Seq metatranscriptomic data and ITS2 metabarcoding, we investigated whether symptom variation correlates with the taxonomic and functional composition of fungal mycobiomes from needles collected in this highly polluted area in the surroundings of Mexico City. Our findings indicate that ozone-related symptoms do not significantly correlate with changes in the taxonomic composition of fungal mycobiomes. However, genes coding for 30 putative proteins were differentially expressed in the mycobiome of asymptomatic needles, including eight genes previously associated with resistance to oxidative stress. These results suggest that fungal communities likely play a role in mitigating the oxidative burst caused by tropospheric ozone in sacred fir. Our study illustrates the feasibility of using RNA-Seq data, accessible from global sequence repositories, for the characterization of fungal communities associated with plant tissues, including their gene expression. [ABSTRACT FROM AUTHOR]

Groundwater serves as the primary source of freshwater in arid and semi-arid regions, rendering them resilient against precipitation scarcity. Various aspects of the drought phenomenon necessitate the application of multivariate analysis and composite drought indices. These composite indices afford a more comprehensive understanding of various drought types. However, few studies have considered the integration of meteorological and groundwater drought information. This research delves into determining a threshold for triggering the transition from meteorological drought to groundwater drought in an arid region (Minab plain). It introduces the Joint Deficit Meteo-Groundwater Drought Index, a result of combining two droughts based on copula function. Furthermore, trivariate drought frequency analysis (severity-duration-peak) is conducted based on three scenarios in three clusters of the Minab Plain. Drought risk is then assessed using conditional probability. The results indicate that the northern and central parts of the Minab Plain face a high risk of meteo-groundwater drought. With increasing drought duration and severity, the peak also rises, placing the entire region at risk of widespread drought. A comprehensive understanding of meteo-groundwater drought and an assessment of its characteristics provide insights into the signals of propagation from meteorological drought to groundwater, facilitating the management of groundwater and surface water resources to mitigate the effects of drought. [ABSTRACT FROM AUTHOR]

Mountain forests provide multiple benefits but are threatened by climate change-induced forest dieback. Although many studies summarize perceptions of forest ecosystem services, relatively few deal with mountain forests. The local population's perception of forest dieback in mountain forests in relation to climate change has rarely been investigated so far. Their perspective is relevant as local people are often deeply attached to "their" forests, they actively use forest ecosystems and—as voters and taxpayers—they need to support the state's adaptation and funding measures. Therefore, this study investigates the climate change and forest dieback perception of local inhabitants in two mountain areas of Southern Germany (the German Alps and the Bavarian Forest) with a quantitative survey based on representative online samples (n = 709). Relying conceptually on van der Linden's (J Environ Psychol 41:112–124, 2015. https://doi.org/10.1016/j.jenvp.2014.11.012) climate change risk perception model, the results show that experiential processing, cognitive and socio-cultural factors are related to locals' forest dieback and climate change perception, while socio-demographics show no or few connections. Nearly two-thirds (64.7%) of the respondents perceive moderate to strong forest dieback, while more than half (55.0%) of the respondents already observe consequences of climate change. The perceptions of climate change and forest dieback are positively correlated with medium to high strength. This shows that forest dieback could be interpreted as an indicator of climate change, which is difficult to observe due to its long-term nature. We identify three groups of respondents regarding preferred forest adaptation strategies to climate change. In general, respondents support nature-based forest adaptation strategies over intense measures. [ABSTRACT FROM AUTHOR]

This study explores the interplay between environmental quality and healthcare spending in five North African countries from 1990 to 2019, considering key socioeconomic variables as determinants. We observe a growing trend in healthcare expenditure, signaling a dedication to improving healthcare systems. Nevertheless, sporadic declines, particularly post-2010 in Libya and Tunisia, highlight the vulnerability of healthcare infrastructure to external shocks, underlining the synergy between healthcare, political stability, and economic development. Simultaneously, the study underscores the potential threat of CO2 emissions to healthcare costs, emphasizing the intrinsic connection between environmental quality and healthcare expenses. Income significantly propels healthcare spending, mirroring the region's pursuit of enhanced living standards and healthcare access. Notably, investments in healthcare infrastructure play a substantial role. Furthermore, the adverse impact of trade openness on healthcare spending stresses the importance of equitable resource allocation and effective healthcare policy implementation. The positive influence of population density underscores the need for tailored healthcare strategies addressing the region's diverse healthcare requirements. Additionally, the U-shaped relationship between healthcare expenditure and CO2 emissions suggests that the studied countries have low pollution levels and have not incurred significant healthcare costs from emissions. However, as they grow economically, environmental conservation becomes crucial to avert harm and resource depletion. While acknowledging limitations like data quality and the need for a more extended time series analysis, a comprehensive approach to healthcare systems, and a holistic view of environmental factors, this study significantly contributes to comprehending the dynamics of healthcare spending, environmental quality, and economic development in North Africa. [ABSTRACT FROM AUTHOR]

Tree mortality and forest dieback episodes are increasing due to drought and heat stress. Nevertheless, a comprehensive understanding of mechanisms enabling trees to withstand and survive droughts remains lacking. Our study investigated basal area increment (BAI), and δ13C-derived intrinsic water-use-efficiency (iWUE), to elucidate beech resilience across four healthy stands in Italy with varying climates and soil water availability. Additionally, fist-order autocorrelation (AR1) analysis was performed to detect early warning signals for potential tree dieback risks during extreme drought events. Results reveal a negative link between BAI and vapour pressure deficit (VPD), especially in southern latitudes. After the 2003 drought, BAI decreased at the northern site, with an increase in δ13C and iWUE, indicating conservative water-use. Conversely, the southern sites showed increased BAI and iWUE, likely influenced by rising CO2 and improved water availability. In contrast, the central site sustained higher transpiration rates due to higher soil water holding capacity (SWHC). Despite varied responses, most sites exhibited reduced resilience to future extreme events, indicated by increased AR1. Temperature significantly affected beech iWUE and BAI in northern Italy, while VPD strongly influenced the southern latitudes. The observed increase in BAI and iWUE in southern regions might be attributed to an acclimation response. [ABSTRACT FROM AUTHOR]

The Zagros oak forests in Iran are facing a concerning decline due to prolonged and severe drought conditions over several decades, compounded by the simultaneous impact of temperature on oak populations. This study in oak woodlands of central Zagros forests in Lorestan province analyzed abiotic factors such as climate properties, topographic features, land use, and soil properties from 1958 to 2022. We found that higher elevation areas with steeper slopes and diverse topography show significant potential for enhancing oak tree resilience in the face of climate change. Additionally, traditional land use practices like livestock keeping and dryland farming contribute to a widespread decline in oak populations. Preserving forest biodiversity and ensuring ecological sustainability requires immediate attention. Implementing effective land-use management strategies, such as protecting and regulating human-forest interaction, and considering meteorological factors to address this issue is crucial. Collaborative efforts from stakeholders, policymakers, and local communities are essential to oppose destructive suburban sprawl and other developments. Sustainable forestry practices should be implemented to improve the living standards of local communities that rely on forests and traditional livestock keeping, offer forestry-related jobs, and ensure social security. Such efforts are necessary to promote conservation awareness and sustainable practices, safeguarding this unique and vital ecosystem for future generations. [ABSTRACT FROM AUTHOR]

While some South American primates are well-studied, many are poorly known to science. This makes reports of their ecology very valuable, especially when the region inhabited is threatened by human activities. We combined data from three independent field studies to provide a better understanding of the behavior, ecology, chemical composition of plant items consumed, and conservation of the Parecis Plateau titi monkey (Plecturocebus parecis), a recently described species from the southern Amazonian Arc of Deforestation. Specifically, we collected behavioral data for eight groups over 8 months and quantified the monkeys' activity budget. To analyze the chemical compounds in the plants eaten, we used vanillin to determine condensed tannin and alkaline precipitation to quantify total alkaloid content. We also determined the extent of forest loss and fragmentation from 2000 to 2019 within the known range of the Parecis Plateau titi monkey using satellite imagery. We found that group size ranged 2–6 individuals, and the monkeys spent 31% of the day foraging, 22% resting, 19% feeding, 14% moving, and 14% in other activities. The monkeys ate 50 plant species from 24 families and appeared to be unusually tolerant of dietary tannins but avoided alkaloids. Habitat modification within the species' range has been extensive: forest cover declined by 16.1% in 2000–2019; the largest areas of continuous forest were reduced by 37.5%; mean fragment size decreased 67.5% (from 421.0–136.9 ha). Forest loss and fragmentation were most significant in the northern half of the species' range and its southern border. Given the Parecis Plateau titi monkey's tolerance for toxic dietary species, the intense modification of its geographic range, and its capacity to live in fragmented habitats, we recommend that future studies investigate these topics across all 37 species of titi monkeys. In addition, recordings of vocal repertoires will improve field surveys and help with population estimates, especially for titi monkey species living in geographic regions that have been heavily modified by humans. [ABSTRACT FROM AUTHOR]

Monitoring the dynamics of land use and land cover (LULC) is imperative in the changing climate and evolving urbanization patterns worldwide. The shifts in land use have a significant impact on the hydrological response of watersheds across the globe. Several studies have applied machine learning (ML) algorithms using historical LULC maps along with elevation data and slope for predicting future LULC projections. However, the influence of other driving factors such as socio-economic and climatological factors has not been thoroughly explored. In the present study, a sensitivity analysis approach was adopted to understand the effect of both physical (elevation, slope, aspect, etc.) and socio-economic factors such as population density, distance to built-up, and distance to road and rail, as well as climatic factors (mean precipitation) on the accuracy of LULC prediction in the Brahmani and Baitarni (BB) basin of Eastern India. Additionally, in the absence of the recent LULC maps of the basin, three ML algorithms, i.e., random forest (RF), classified and regression trees (CART), and support vector machine (SVM) were utilized for LULC classification for the years 2007, 2014, and 2021 on Google earth engine (GEE) cloud computing platform. Among the three algorithms, RF performed best for classifying built-up areas along with all the other classes as compared to CART and SVM. The prediction results revealed that the proximity to built-up and population growth dominates in modeling LULC over physical factors such as elevation and slope. The analysis of historical data revealed an increase of 351% in built-up areas over the past years (2007–2021), with a corresponding decline in forest and water areas by 12% and 36% respectively. While the future predictions highlighted an increase in built-up class ranging from 11 to 38% during the years 2028–2070, the forested areas are anticipated to decline by 4 to 16%. The overall findings of the present study suggested that the BB basin, despite being primarily agricultural with a significant forest cover, is undergoing rapid expansion of built-up areas through the encroachment of agricultural and forested lands, which could have far-reaching implications for the region's ecosystem services and sustainability. [ABSTRACT FROM AUTHOR]

Forest decline caused by climate change has been a growing challenge for European foresters for decades. The accumulation of tree-related microhabitats (TreMs) and deadwood during decline can enhance stand structural heterogeneity and provide crucial habitat features for many forest ecological guilds. We analysed changes in deadwood and TreM assemblages using a trait-based approach in three case studies: drought-induced decline in highland Pyrenean fir and lowland oak forests, and windstorm/pest-induced dieback in highland Bavarian spruce forests. Decline caused significant changes in deadwood and TreM characteristics and composition in three forest contexts. However, tree density with cavities, exudates, or crown deadwood was not linked to decline intensity. Declining conifer forests had more large deadwood and downed woody debris, and their TreM assemblages were more saproxylic, less epixylic, and included more cracks and exposed sapwood. TreM assemblages in drought-declining forests had higher diversity, functional richness, and more dead tops than healthy stands. In Bavarian spruce forests, there was more decayed downed deadwood, and the TreM assemblages were more associated with the base of the tree, snags, and logs. Overall, forest decline significantly boosts ecological niche resources, typically scarce in managed forests, which could benefit many forest biodiversity groups. Though post-disturbance management should respect tree species-dependent economic balance and avoid phytosanitary risks, it should also consider the ecological benefits of decline-induced heterogeneity. [ABSTRACT FROM AUTHOR]

Background: We analyze the forest carbon stock development following the recent historically unprecedented dieback of coniferous stands in the Czech Republic. The drought-induced bark-beetle infestation resulted in record-high sanitary logging and total harvest more than doubled from the previous period. It turned Czech forestry from a long-term carbon sink offsetting about 6% of the country's greenhouse gas emissions since 1990 to a significant source of CO2 emissions in recent years (2018–2021). In 2020, the forestry sector contributed nearly 10% to the country's overall GHG emissions. Using the nationally calibrated Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) at a regional (NUTS3) spatial resolution, we analyzed four scenarios of forest carbon stock development until 2070. Two critical points arise: the short-term prognosis for reducing current emissions from forestry and the implementation of adaptive forest management focused on tree species change and sustained carbon accumulation. Results: This study used four different spruce forest dieback scenarios to assess the impact of adaptive forest management on the forest carbon stock change and CO2 emissions, tree species composition, harvest possibilities, and forest structure in response to the recent unprecedented calamitous dieback in the Czech Republic. The model analysis indicates that Czech forestry may stabilize by 2025 Subsequently, it may become a sustained sink of about 3 Mt CO2 eq./year (excluding the contribution of harvested wood products), while enhancing forest resilience by the gradual implementation of adaptation measures. The speed of adaptation is linked to harvest intensity and severity of the current calamity. Under the pessimistic Black scenario, the proportion of spruce stands declines from the current 43–20% by 2070, in favor of more suited tree species such as fir and broadleaves. These species would also constitute over 50% of the harvest potential, increasingly contributing to harvest levels like those generated by Czech forestry prior to the current calamity. The standing stock would only be recovered in 50 years under the optimistic Green scenario. Conclusion: The results show progress of adaptive management by implementing tree species change and quantify the expected harvest and mitigation potential in Czech forestry until 2070. [ABSTRACT FROM AUTHOR]

Soil erosion poses an environmental threat to the ecosystem functions. Land use and land cover (LULC) changes are largely responsible for soil erosion severity. This study aimed to evaluate the impacts of LULC on soil erosion and erosion distribution in the Laonung watershed over the study period (1995–2016). To model the response of soil erosion to LULC changes, a physiographic soil erosion–deposition (PSED) model is employed, which incorporates Geographic Information Systems (GIS) with rain-runoff models and erosion–deposition models. The results revealed that over a three period (1995, 2008 and 2011), agricultural land, grassland, bare land, water bodies, and other land uses increased, whereas forest land declined by 11,424 × 104 m2 (2008 relative to 1995) and 16,159 × 104 m2 (2011 relative to 1995). In addition to the land use, landslide was considered as a land cover in this study. As landslides dramatically alter the land cover dynamics of mountainous regions in Taiwan. The landslide areas substantial changed over the period 2003 to 2016 (847 × 104 m2–9474 × 104 m2). The significant increase in landslide area together with the abrupt dynamics in LU severely aggravated soil erosion. Compared with the period of primeval forest, total soil erosion increased from 29,295 × 104 m3 to 102,597 × 104 m3 (1995–2011 LU) and 205,833 × 104 m3 (LULC). The study has illustrated how LULC changes strongly affects soil erosion. [ABSTRACT FROM AUTHOR]

Soil respiration (Rs) is the largest outward flux of carbon (C) from terrestrial ecosystems, accounting for more than half of total temperate forest C loss. Evaluating the drivers of this globally important flux, as well as identifying autotrophic (Ra) and heterotrophic (Rh) responses, is critical in the era of rapid global change because small changes could result in disproportionally large impacts to ecosystem C balance. We assessed four years of Rs and Rh from the Forest Resilience Threshold Experiment (FoRTE) to better understand how soil C fluxes respond to a disturbance simulating phloem-disrupting insects. This replicated experiment spanning multiple landscape ecosystems contains four disturbance severities of 0, 45, 65 and 85% gross defoliation as well as two disturbance types targeting the upper and lower canopy. We found an immediate and sustained decline in Rs following phloem disruption that persisted for three years and was proportional to severity. Proportional declines in basal soil respiration and fine-root production with increasing disturbance severity and stable Rh lead us to conclude that Ra drove the suppression of Rs into the third year following disturbance. These responses were conserved across four landscape ecosystems, suggesting the mechanisms causing Rs to decline following phloem disruption were similar despite large differences in composition and productivity. The 3-year reduction of C losses through Rs and, contrastingly, sustained C storage through wood production suggests ecosystem C balance may have remained relatively stable in the first few years following disturbance, even at the highest severity. [ABSTRACT FROM AUTHOR]

Context: Syntheses of vegetation responses over the last century are rare for the Alps, and limited in chronological and taxonomical resolution. We propose that pollen records from glaciers can be used to fill this gap. Objectives: Our aim is to evaluate the reliability of glacier pollen records as historical archives of biodiversity to obtain plant diversity data and landscape changes. In detail, we aim at reconstructing taxa and vegetation trends in central sector of the Italian Alps over the last century integrating pollen-inferred vegetation trends with drifts in spatially explicit land-cover. Methods: Our study area is the Lombardy region (Italy). We performed pollen analyses of Adamello glacier cores, and reconstructed trends of single taxa and main vegetation types since the 1950s. Pollen-inferred vegetation trends were calculated using pollen indicators obtained from a database of vegetation-plot observations. The reliability of these trends is evaluated by comparison with spatially explicit tendencies reconstructed with a time-series of land-cover maps. Results: Pollen records well represent the natural vegetation types as the temperate and the riverine forests, and the anthropic vegetation as crops and alien species. From the 1980s a thermophilisation took place, and warm-demanding native and alien species expanded. The contraction of cultivated land since the 1970s, and the decline of the riverine forest appear driven by socio-economic factors. Conclusions: We conclude that pollen-inferred vegetation trends from glaciers can be used to obtain large scale biodiversity information. This is relevant also for areas where biodiversity data are scarce but needed for landscape management planning. [ABSTRACT FROM AUTHOR]

This paper focuses on the current state of mangroves in Egypt, analyses how climate change is affecting mangrove forests and suggests a conservation strategy to safeguard this valuable maritime resource. Mangroves in Egypt are primarily found in regions around the Red Sea, making them popular for ecotourism across the globe. A crucial breeding and feeding ground for many commercial fishery species, mangroves are a maritime habitat that is both economically and environmentally significant and a variety of living things call them home. Mangroves are one of the most threatened tropical and subtropical ecoregions in the world. These threats come from both natural and human sources, including oil spills, human waste runoff, herbicide use, and coastal development, all of which have the potential to harm the environment. Mangrove habitats are immediately impacted by salinity changes and rising sea levels brought on by climate change. This is unfortunate as mangroves are one of the most important global carbon sinks, and their loss due to climate change may accelerate sea level rise and ocean acidification, which will cause the extinction of numerous commercial fish species. A conservation strategy should be implemented to safeguard the mangroves around the Egyptian Red Sea by using mitigation techniques, creating marine protected zones near the mangroves, and consulting the owners of the mangrove stalks. Analysis of multi-temporal satellite imagery is one of the most significant methods to assist decision-makers and environmental planners in obtaining high-precision information about environmental and climatic changes. Analysis of satellite imagery is a valuable way to detect, monitor, assess and map the environmental, human, and natural activities that are threatening the growth of the mangrove forest ecosystem. Change detection analyses using satellite imagery were conducted to evaluate the effects of rapid coastal sustainable development, including human urban and tourism activities; the decline and destruction of large areas of the mangrove forest for animal feeding along camel trade roads; and the threat of natural impacts such as flash flooding, coastal and soil erosion or human impacts such as established desalination plants and other human activities along the coastal zone of the Egyptian Red Sea. [ABSTRACT FROM AUTHOR]

Urbanization poses a significant threat to biodiversity, particularly in developing nations characterized by high rural–urban migration and inadequate urban planning that fails to consider nature conservation. Insufficient information on how to effectively integrate urban expansion and nature conservation exacerbates environmental problems and hampers mitigation efforts. In this study, we assessed the expansion of Jimma City, a typical rapidly growing city in Ethiopia, over the past 35 years, projected changes for the next 50 years, and identified priority areas for conservation. Landsat satellite images from 1985 and 2020 were utilized to map major land cover types and quantify temporal changes. We employed a Markov chain model to predict changes over the next 50 years and a GIS-based multi-criteria approach to identify conservation priority areas. Our findings underscore the adverse effect of urban expansion on natural habitats. Over the past three decades, built-up areas expanded by sevenfold (721%; 2227 ha) while croplands expanded by 34% (4155 ha). Conversely, natural habitats experienced significant declines: forest cover declined by 39% (5209 ha), grassland by 20% (655 ha) and wetland by 28% (638 ha). Projecting the current trend over the next 50 years showed built-up areas to further increase by about fourfold (436%, 3565 ha). However, open water, wetland, natural forest, and cropland are predicted to decline by 81% (120 ha), 40% (660 ha), 42% (3455 ha), and 55% (8848 ha), respectively. Given the current rate of population growth and rural–urban migrations, urban expansion appears inevitable. Our study emphasizes the importance of designating at least 9040 ha (28%) of the land within the city and its surroundings as high-priority areas for biodiversity conservation. These areas encompass approximately 95% of the remaining forest remnants, 78% of the wetland area, and 22% of the grassland. It is imperative for urban administrations in developing nations to adopt sound policies, strategies, and planning approaches that support the integration of urban development and nature conservation, with special attention given to the preservation of key biodiversity areas. Such efforts are crucial for fostering inclusive, safe, resilient, and sustainable cities. [ABSTRACT FROM AUTHOR]

Context: Western Chilean Patagonia is an isolated temperate region with an important proportion of intact forest landscapes (IFL) that was subjected to large-scale fires over 60 years ago. However, there is no empirical evaluation of the land cover dynamics to establish the forest loss and recovery, and the effect on the landscape structure and function, and remnant IFL following the fires. Objectives: The present study addressed the following questions: (1) What have been the main trends of the land cover dynamics between 1984 and 2018 following earlier fires, and how have these trends shaped the spatial patterns and potential carbon stock of forests in western Patagonia? (2) What proportion of forest landscape remains intact following fires in this region? Methods: We selected the Coyhaique Province (1,231,910 ha) in western Chilean Patagonia as the study area. Land cover maps for three dates (1984, 2000, 2018) were used to evaluate landscape dynamics after fires. A map of persistence and change occurrence was made to estimate the IFL area over the 1984–2018 period. Landscape metrics were used to assess landscape structure change, and potential carbon stock was estimated based on a literature review. Results: Following fires, the main land cover changes between 1984 and 2018 were loss of ~ 32,600 ha of old-growth forest and a recovery of ~ 69,000 ha of second-growth forest. The increase in second-growth forest area mainly resulted from loss of agricultural cover (~ 41% of the area). Despite these changes, ~ 61% of the area could potentially remain as IFL after fires. Over the 1984–2018 period, a slight increase in fragmentation of old-growth forest, and a decline in second-growth forest were observed. Coyhaique Province experienced a slight increase (3.6%) in overall potential carbon stock, likely as a result of second-growth forest recovery. Conclusions: Our study provides the first evidence of the western Patagonia landscape state after more than six decades since the large-scale fires. The results provide baseline information on landscape structure and function that could help to make conservation and forest management decisions on specific territory areas. [ABSTRACT FROM AUTHOR]

Background: The European Union (EU) has committed to achieve climate neutrality by 2050. This requires a rapid reduction of greenhouse gas (GHG) emissions and ensuring that any remaining emissions are balanced through CO2 removals. Forests play a crucial role in this plan: they are currently the main option for removing CO2 from the atmosphere and additionally, wood use can store carbon durably and help reduce fossil emissions. To stop and reverse the decline of the forest carbon sink, the EU has recently revised the regulation on land use, land-use change and forestry (LULUCF), and set a target of − 310 Mt CO2e net removals for the LULUCF sector in 2030. Results: In this study, we clarify the role of common concepts in forest management – net annual increment, harvest and mortality – in determining the forest sink. We then evaluate to what extent the forest sink is on track to meet the climate goals of the EU. For this assessment we use data from the latest national GHG inventories and a forest model (Carbon Budget Model). Our findings indicate that on the EU level, the recent decrease in increment and the increase in harvest and mortality are causing a rapid drop in the forest sink. Furthermore, continuing the past forest management practices is projected to further decrease the sink. Finally, we discuss options for enhancing the sinks through forest management while taking into account adaptation and resilience. Conclusions: Our findings show that the EU forest sink is quickly developing away from the EU climate targets. Stopping and reversing this trend requires rapid implementation of climate-smart forest management, with improved and more timely monitoring of GHG fluxes. This enhancement is crucial for tracking progress towards the EU's climate targets, where the role of forests has become – and is expected to remain – more prominent than ever before. [ABSTRACT FROM AUTHOR]

Climate warming may induce growth decline in warm-temperate areas subjected to seasonal soil moisture deficit, whereas increasing atmospheric CO2 concentration (Ca) is expected to enhance tree growth. An accurate understanding of tree growth and physiological processes responding to climate warming and increasing Ca is critical. Here, we analyzed tree-ring stable carbon isotope and wood anatomical traits of Pinus tabuliformis from Qinling Mountains in China to understand how lumen diameter (LD) determining potential hydraulic conductivity and cell-wall thickness (CWT) determining carbon storage responded to climate and Ca. The effects of climate and Ca on intrinsic water-use efficiency (iWUE) were isolated, and iWUE values due to only-climate (iWUEClim) and only-CO2 effects (iWUECO2) were obtained. During a low-iWUE period, the influences of climate on earlywood (EW) LD and latewood (LW) CWT prevailed. During a high-iWUE period, CO2 fertilization promoted cell enlargement and carbon storage but this was counteracted by a negative influence of climate warming. The limiting direct effects of iWUEClim and indirect effects of climate on EW LD were greater than on LW CWT. P. tabuliformis in temperate forests will face a decline of growth and carbon fixation, but will produce embolism-resistant tracheids with narrow lumen responding to future hotter droughts. [ABSTRACT FROM AUTHOR]

Tree mortality is an important process of forest stand dynamics and knowledge of it is fundamental to implement adequate management strategies. Subject to several factors, tree mortality can induce different spatial patterns on the remaining live and dead trees. While spatially clustered tree mortality in young forests is often driven by competition, in old-growth forests, spatially clustered tree mortality is often caused by disturbance agents. This study is focused on a spatiotemporal analysis of tree mortality in a mature temperate forest located in central Mexico dominated by Pinus montezumae and Alnus firmifolia. We used tree locations from a permanent plot (300 × 300 m) measured over a 20-year period. The results, from applying point pattern analysis, showed that the spatial pattern of all dead trees was clustered at short to medium distances, but showed no clear deviation from complete spatial randomness at longer distances. Similar results were found for P. montezumae and A. firmifolia. Using the bivariate mark-connection function (alive and dead trees), no tree mortality caused by competition was discernable, only A. firmifolia showed a tendency toward competition-introduced mortality around 15 m. Regarding forest structure, alive trees retained a clustered distribution and size heterogeneity at different distances during the measurement period. Thus, there was evidence that the resulting spatial pattern of tree mortality could be explained by disturbance agents such as droughts rather than tree competition. Therefore, the results of this study can contribute to implement management strategies based on the principles of continuous cover forestry and provide novel information regarding tree mortality in Mexican montane forests. [ABSTRACT FROM AUTHOR]

Land use and land cover (LULC) is a major concern of global environmental change, particularly the case, in developing countries. In the Central Ethiopian Rift Valley (CRV), unprecedented changes in LULC have been observed over the last decades. This study aims to scrutinize the dynamics of the CRV over a timespan of three decades (1984–2013). Satellite imageries were acquired from Multispectral Scanner System, Thematic Mapper, and Enhanced Thematic mapper for the years 1984, 1995, and 2013 respectively. The data were obtained from the United States Geological Survey and Ethiopian Geospatial Information Institute. In addition, Focus Group Discussions and Key Informants Interviews were undertaken to support analysis and interpretation of LULC anomalies, identify drivers, and associated impacts. Geospatial technologies were used to analyze the extent of LULC change across the study period. An object-oriented supervised classification and a change detection technique were applied to compartmentalize the change into six LULC classes. Results revealed that farmlands and built-up areas have shown continuous progressive expansion at the expense of bareland and forestland. Farmland and built-up area in 1984 were expanded from 33.3% and 2.6% to 40.6% and 8.2% in 2013, respectively. In contrast, forestland and bareland coverages in 1984 were dwindled from 11.7% and 17.7% to 4.2% and 10.1% in 2013, respectively. Comparatively, shrubland and waterbody were also slightly augmented by 1.9% and 0.2% from 1984 to 2013. Therefore, the result suggested that policymakers and development actors must take appropriate actions to minimize the progressive decline of forest cover in the milieu. [ABSTRACT FROM AUTHOR]

While driving regional economic development, coal mining also causes environmental problems. Changes in land use are associated with mining impact vegetation's net primary productivity (NPP). This, in turn, can impact vegetation's carbon fixation capacity. Understanding how these impacts operate can inform vegetation restoration efforts in former mining areas and preserve ecological stability. In this paper, the NPP of the study area from 2000 to 2019 was retrieved based on the Carnegie–Ames–Stanford Approach (CASA) model, and the spatial and temporal distribution characteristics of NPP of the study area were discussed. Meanwhile, combined with the land-use data of the European Space Agency (ESA) in 2000, 2010, and 2019, the impact of land-use changes on regional vegetation NPP was discussed from the perspective of landscape ecology. The results showed that the CASA model using inverted NPP data gave results that compared favorably with data measured in the field. The annual average vegetation NPP in the study area during the study period was 44.51 g C m−2 a−1. NPP changes showed considerable spatial heterogeneity, but the same overall trends in fluctuation. The study area experienced a decline in both forested and grassland area from 2000 to 2010. The NPP of all four land types decreased. Forested and other land types increased from 2010 to 2019, and the NPP of all four categories increased. Land-use changes over the study period of two decades promoted NPP growth, contributing 44.66% and 93.9%, respectively. Except for the aggregation index, landscape pattern indices showed a positive correlation with NPP. NPP values in 2000, 2010, and 2019 all increased, showing the highest ranked principal components based on landscape indices. The NPP in the study area strongly depends on human activities. Maintaining the current vegetation status would increase NPP in the study area and enhance the vegetation's carbon fixation capacity. [ABSTRACT FROM AUTHOR]

Insects are declining, but the underlying drivers and differences in responses between species are still largely unclear. Despite the importance of forests, insect trends therein have received little attention. Using 10 years of standardized data (120,996 individuals; 1,805 species) from 140 sites in Germany, we show that declines occurred in most sites and species across trophic groups. In particular, declines (quantified as the correlation between year and the respective community response) were more consistent in sites with many non-native trees or a large amount of timber harvested before the onset of sampling. Correlations at the species level depended on species' life-history. Larger species, more abundant species, and species of higher trophic level declined most, while herbivores increased. This suggests potential shifts in food webs possibly affecting ecosystem functioning. A targeted management, including promoting more natural tree species composition and partially reduced harvesting, can contribute to mitigating declines. Species richness and biomass of insects has declined on average across 140 forest sites sampled over a decade in Germany, with larger, more abundant, and carnivorous species found to be more susceptible to decline. [ABSTRACT FROM AUTHOR]

The increase in frequency, severity, and duration of droughts poses as a serious issue to the management of forests in the Iberian Peninsula, with particular emphasis on the decline of forest growth and forest dieback. Hence, the adoption of adaptation and mitigation measures in forest ecosystems that are more vulnerable to drought is a pressing matter that needs to be addressed in the near future. This work aims at identifying the regions in the Iberian Peninsula where forest exhibit high vulnerability to drought conditions. To accomplish that, a vulnerability map is produced by considering three pillar components: exposure, sensitivity, and adaptive capacity to drought. Exposure is estimated based on the multi-scalar drought index Standardized Precipitation-Evapotranspiration Index (SPEI) and aridity, while the remotely sensed Vegetation Health Index (VHI) and mean forested cover are used to assess the regions' sensitivity to drought. Finally, elevation, water table depth, fire radiative energy, and annual solar irradiation are compiled as indicators to assess adaptive capacity. Principal component analysis was then applied to the three pillar components to identify the areas more vulnerable to drought. This approach allows for the identification of forested areas vulnerable to drought in terms of vulnerability classes automatically determined. Forests presented very high vulnerability in eastern Spain, and central Portugal. Within the most vulnerable vegetation communities, mosaic tree and shrub types revealed to be extremely vulnerable to droughts in the Iberian Peninsula, followed by needle-leaved forests (in Central Portugal, and Northeast Iberia). This work highlights the regions and primary vegetation communities to which the effort of adapting and mitigating drought consequences should be utterly enforced by the responsible authorities. [ABSTRACT FROM AUTHOR]

Forest decline, which occurs in mountainous regions in many countries, may result from the effects of acid fog, ozone, or deposition of other pollutants. We observed wet deposition of air pollutants at different altitudes on Mt. Oyama, situated southwest of Tokyo, for 1994 until 2019. During this period, the domestic atmospheric environment was improved in Japan. The average concentration of air pollutants around all the sampling sites on Mt. Oyama decreased by 63.01%, 32.08%, 8.80%, and 39.73% for NH3, HCl, HNO3, and SO2, respectively. The volume weighted mean (VWM) pH values showed an increasing trend for bulk deposition (+0.70% y-1), fog water (+2.58% y-1), and throughfall (+2.60% y-1). Stemflow also increased (cedar, +1.17% y-1; fir, +0.82% y-1), although it included organic acids dissolved from the stem and it primarily had a low VWM pH value. The overall pH value of the fog water increased at the site, although acidic fog was still observed. Comparing fog water between winter and summer, a significant increase in pH occurred in summer, whereas no change occurred in winter. In summer, the sources of pollutants at Mt. Oyama are mainly from mainland Japan, and the frequency of low-pH acidic fog decreased annually. In winter, Mt. Oyama was affected by transboundary pollution, and acid fog occasionally occurred. Improvements in the domestic atmospheric environment and control of transboundary pollution will provide better conditions for mountain ecology that are free from acidic pollutants. [ABSTRACT FROM AUTHOR]

Context: A significant forest decline has been noticed these last years in Europe. Managers need tools to better anticipate these massive events. Objectives: We evaluated the efficiency of easily available data about environmental conditions and stand characteristics to determine different levels of vulnerability. Methods: We combined remote sensing images, photo-interpretation, and digital models describing environmental conditions within a modelling approach to achieve spatial vulnerability assessment of the stands. We focused on silver fir and Norway spruce stands in the Vosges mountains (8900 km2, northeastern France), where severe symptoms of decline are visible. Results: Silver fir were predicted highly vulnerable on 7% of their area versus 33% for Norway spruce. Using an independent dataset, we observed ten-times (silver fir) and two-times (Norway spruce) higher mortality rates in the units with a high level of vulnerability than in the others. About half of the model deviance was directly or indirectly explained by variables related to water stress (soils displaying low water availability, having suffered severe drying events these last years). Furthermore, the stands acclimatised to drought conditions were more resilient. Stand characteristics also influenced dieback spread, suggesting that an evolution of silvicultural practices toward mixed stands with broadleaved species and uneven-aged trees can contribute to better adapt to future climate conditions. Conclusion: Vulnerability maps based on easily available geographic information describing climate, soil, and topography can efficiently discriminate canopy mortality patterns over broad areas, and can be useful tools for managers to mitigate the effects of climate change on forests. [ABSTRACT FROM AUTHOR]

Context: Habitat loss is a major factor influencing declines in landscape connectivity for many species, but forest patch configuration and changes in matrix permeability can also represent important drivers. An evaluation of which of these factors are predominant is key to guiding landscape planning at a regional scale. Objectives: We aimed to quantify the loss of jaguar (Panthera onca) habitat connectivity and to analyse the drivers behind this process in the Atlantic Forest. Methods: We analysed trends in jaguar habitat connectivity between 1973 and 2015 in the Upper Paraná Atlantic Forest and the three countries that comprise the eco-region (Argentina, Brazil, and Paraguay). We used graph-based indices and jaguar movement data to evaluate changes in forest area, forest patch configuration and matrix permeability. Results: Jaguar habitat connectivity decreased throughout the entire period, with a loss of up to 93% of connectivity. Changes in forest patch configuration and forest area loss were the main drivers of this trend, but the effect of decreased matrix permeability was also significant. These processes together largely increased the negative effect of forest area declines on jaguar habitat connectivity. Connectivity trends for the three countries in the study area were negative, with the highest forest decline in Paraguay and Brazil compared to Argentina. Conclusions: Analysing landscape dynamics using metrics that go beyond measuring net forest area is key when assessing landscape connectivity for jaguars. Future studies evaluating landscape connectivity should incorporate habitat patch configuration and matrix permeability in addition to forest loss, aspects that should also be considered when undertaking habitat restoration measures. [ABSTRACT FROM AUTHOR]

Drought-induced forest dieback can lead to a tipping point in community dominance, but the coupled response at the tree and stand-level response has not been properly addressed. New spatially and temporally integrated monitoring approaches that target different biological organization levels are needed. Here, we compared the temporal responses of dendrochronological and spectral indices from 1984 to 2020 at both tree and stand levels, respectively, of a drought-prone Mediterranean Pinus pinea forest currently suffering strong dieback. We test the influence of climate on temporal patterns of tree radial growth, greenness and wetness spectral indices; and we address the influence of major drought episodes on resilience metrics. Tree-ring data and spectral indices followed different spatio-temporal patterns over the study period (1984–2020). Combined information from tree growth and spectral trajectories suggests that a reduction in tree density during the mid-1990s could have promoted tree growth and reduced dieback risk. Additionally, over the last decade, extreme and recurrent droughts have resulted in crown defoliation greater than 40% in most plots since 2019. We found that tree growth and the greenness spectral index were positively related to annual precipitation, while the wetness index was positively related to mean annual temperature. The response to drought, however, was stronger for tree growth than for spectral indices. Our study demonstrates the value of long-term retrospective multiscale analyses including tree and stand-level scales to disentangle mechanisms triggering and driving forest dieback. [ABSTRACT FROM AUTHOR]

Forest dieback due to climate change has severe consequences for the sensitive environments of mountain forests which provide important ecosystem services for local communities, lowlands inhabitants, and visitors. However, this phenomenon is sometimes hard to identify for the lay public as it can manifest as a slow-onset phenomenon with rather inconspicuous signals or as large-scale disturbances like in the case of bark beetle outbreaks. The aim of this contribution is to analyze whether lay people perceive climate change-induced forest dieback in the landscape or not and what kind of damage they identify. To address this issue, we carried out a cross-comparison case-study in two mountain areas in France and Germany. To analyze the data, we introduce an innovative variable clustering approach to identify different groups of respondents based on their perception of climate change and forest dieback. Five groups of respondents—illustrating different degrees of worry—were identified in each case study: the non-alarmist, the carefree, the least informed, the worried, and the alarmist. These results show that both phenomena are not perceived as distant but as happening here and now; and that their perceptions are influenced by local contexts and personal experiences. We finally show that public perception of forest dieback has influenced the agenda setting on the enactment of new forest policies. [ABSTRACT FROM AUTHOR]

Oak dieback disease caused by the fungus Paecilomyces formosus threatens oak trees in the Zagros forests in western Iran. Various insects, such as wood-infesting beetles (Coleoptera), may play a role in dissemination of P. formosus. We collected larvae and adult insects from branch wood of oak trees with dieback symptoms in the Zagros forests. For larval identification, the mitochondrial gene cytochrome c oxidase I (COXI) was amplified by polymerase chain reaction (PCR). Fungal isolates from wood and insects collected from the sampled oaks were identified by morphology, acid production on creatine sucrose agar (CREA) medium, phylogeny of DNA sequence data for the β-tubulin gene and the internal transcribed spacer (ITS) rDNA. To detect P. formosus in larvae and adult insects, we used a nested PCR assay with the species-specific primer pairs PaMF and PaMR. The insects that most often tested positive for P. formosus were larvae of the buprestids Acmaeodera sp. and Chrysobothris affinis, and larvae of the cerambycid Trichoferus campestris. Adults of C. affinis and Calchaenesthes diversicolis (Cerambycidae), which were collected from within their galleries, also tested positive. Beetle larvae of Anthaxia sp. (Buprestidae), Latipalpis plana (Buprestidae), Monochamus sp. (Cerambycidae) and Crypticus gibbulus (Tenebrionidae) also tested positive. Larvae that tested negative for P. formosus were species of Cossidae (Lepidoptera), Elateridae (Coleoptera), Gasteruptiidae (Hymenoptera) and Syrphidae (Diptera). Future research is needed to determine whether any of these insects can serve as vectors of P. formosus. These results can be used to target-specific insects for monitoring. [ABSTRACT FROM AUTHOR]

Scientific and public interest in acid deposition and its ecological impacts have increased throughout 1990s in East Asia (Northeast and Southeast Asia). After being established in 2001, the Acid Deposition Monitoring Network in East Asia (EANET) celebrates the 20th anniversary in 2021, and is now being expanded in scope reflecting the shifting social concern from acid deposition to broader air quality and climate change in recent years. This paper reviews the past 30 years of development of scientific research and policy related to acid deposition in East Asia. Since the onset of the twenty-first century, East Asia has had the highest SO2 and NOx emissions in the world by continents, with substantial economic developmental inequality among countries. An overview of studies on sulfur and nitrogen deposition, the acidification of inland water and forest soil, and forest decline reveal that although limited acidification of inland water and forest soils have been documented, no decline in the populations of fish and other aquatic biota has been reported in East Asia. After a review of policy-oriented modeling studies on source receptor relationships and the critical loads of sulfur and nitrogen in East Asia, the history of EANET and its success and challenges are discussed. Finally, the importance of epistemic communities as the interface between science and policy in the region is discussed. Regional governance and cooperation are essential for reducing the emission of greenhouse gases, especially short-lived climate pollutants and atmospheric pollutants to realize the co-benefits of global climate change mitigation and improved air quality. [ABSTRACT FROM AUTHOR]

Forest dieback in the last decade has been reported all over the world and not only causes a significant loss of forest yield but also affects successional trajectories. Here, we investigate the plant communities associated with Pinus mugo subsp. mugo dieback patches in Maiella massif. Dieback patches were examined by using satellite images to describe the occurrences and distribution. According to dieback patch size, we identified three ontogenetic stages: small, medium and large. To assess the effect of P. mugo on coexisting species, patch was divided into four belts according to P. mugo healthy status: OUT, FRONT, DEAD and IN zone. Within the four belt zones for each of the three ontogenetic stages, a vegetation analysis was conducted. Overall, 35 dieback patches were recorded and all are characterized by a circular shape and a size ranging from a few meters to 76.1 m. The linear correlation between the width of the inner regeneration belt and the total diameter of the patch suggests that the dieback area expands centrifugally due to the death of standing P. mugo. The increased resources, in terms of light availability caused by dieback, contribute to higher plants diversity in DEAD belts with the highest cover of hemicryptophytes. Contrariwise, in the OUT belts, not affected by dieback, plant diversity was the lowest with the highest cover of phanerophytes and a good contingent of nemoral species. Dieback affects forest structure and leads to sudden vegetation shifts that play an important role in maintaining biodiversity by allowing alternation between forest and grassland ecosystems. [ABSTRACT FROM AUTHOR]

Oak decline is the most serious oak forests threat caused by a combination of biotic and abiotic factors in the world. In a survey on oak decline, 57 Biscogniauxia isolates were obtained from infected twigs and trunks of oak trees showing decline symptoms in Zagros forests, west of Iran. Based on morphology, cultural characteristics and DNA sequences data (ITS region and part of the β-tubulin gene) isolates were characterized as Biscogniauxia rosacearum and Obolarina persica. Most of the isolates belonged to B. rosacearum (40 isolates/70%). Pathogenicity test of B. rosacearum and O. persica on 2-year-old potted healthy oak seedlings confirmed the pathogenicity of both species on Quercus brantii. We report B. rosacearum for the first time on Q. brantii, Q. infectoria and Q. libani in the world. Furthermore, O. persica is reported for the first time on Q. libani and from West Azarbaijan Province. Based on the phylogenetic analyses, four species in two genera Camillea (C. obularia and C. tinctor) and Obolarina (O. dryophila and O. persica) are transferred to the genus Biscogniauxia Kuntze and two new combinations Biscogniauxia tinctor and Biscogniauxia persica are introduced. [ABSTRACT FROM AUTHOR]

Context: Many forest ecosystems around the world are facing increasing drought-induced dieback, causing mortality patches across the landscape at multiple scales. This increases the supply of biological legacies and differentially affects forest insect communities. Objectives: We analysed the relative effects of local- and landscape-level dieback on local saproxylic beetle assemblages. We assessed how classical concepts in spatial ecology (e.g., habitat-amount and habitat-patch hypotheses) are involved in relationships between multi-scale spatial patterns of available resources and local communities. Methods: We sampled saproxylic beetle assemblages in commercial fir forests in the French highlands. Through automatic aerial mapping, we used percentage of dead tree crown pixels to assess dieback levels at several nested spatial scales. We analysed beetle taxonomic, phylogenetic and functional diversity related to differing levels of multi-scale dieback. Results: We found that taxonomic, functional, and phylogenetic diversity of saproxylic beetle assemblages significantly benefitted from forest dieback, at both local and landscape scales. We detected significant effects in the multiplicative models combining local and landscape variables only for phylogenetic diversity. Increased landscape-scale dieback also caused a functional specialisation of beetle assemblages, favouring those related to large and well-decayed deadwood. Conclusions: Increasing tree mortality under benign neglect provides conservation benefits by heterogenising the forest landscape and enhancing deadwood habitats. Legacy retention practices could take advantage of unharvested, declining forest stands to promote species richness and functional diversity within conventionally managed forest landscapes. [ABSTRACT FROM AUTHOR]

Addressing undesirable changes associated with the driving forces of land use cover change are critical to sustainable land management, and the future modeling of land use systems in developing countries. The study accentuates local drivers of land use cover change in Southwestern Ghana using a mixed-method approach. The approach aided in identifying key land-use drivers, using different research strategies for comparisons through confidence level analysis and Analytic Hierarchy Process. We used expert interviews, existing literature and geostatistical tools to ascertain the driving forces triggering such unprecedented changes. Landsat imagery 5 MSS, 4 and 5 TM, 7 ETM + and 8 OLI/TIRS were acquired from the United States Geological Survey's website. Land-use analysis revealed a decline in forests (− 82.41%) and areas covered by waterbodies (− 27.39%). A fundamental drift in built-up (+ 1288.36%) and farmlands/shrubs (+ 369.81%) areas were also observed. The contribution rate of change analysis revealed built-environment and increasing population contributed the most to surface temperature and land-use change. A steady increase in surface temperature can be attributed to the undesirable changes associated with land-use systems over the past 50 years. Socio-economic development in Southwestern Ghana is fuelling interest in studies related to land use cover change. Biophysical, cultural and technological factors are considered key drivers despite the "medium-to-very low confidence" in results generated. They could potentially impact climate-sensitive sectors that significantly modify land-use systems from the pessimists' and optimists' perspectives. Standpoints established through this study will enrich basic datasets for further studies at the continental level. [ABSTRACT FROM AUTHOR]

Background: Countries seeking to mitigate climate change through forests require suitable modelling approaches to predict carbon (C) budget dynamics in forests and their responses to disturbance and management. The Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) is a feasible and comprehensive tool for simulating forest C stock dynamics across broad levels, but discrepancies remain to be addressed in China. Taking Guizhou as the case study, we customised the CBM-CFS3 model according to China's context, including the modification of aboveground biomass C stock algorithm, addition of C budget accounting for bamboo forests, economic forests, and shrub forests, improvement of non-forest land belowground slow dead organic matter (DOM) pool initialisation, and other model settings. Results: The adequate linear relationship between the estimated and measured C densities (R2 = 0.967, P < 0.0001, slope = 0.904) in the model validation demonstrated the high accuracy and reliability of our customised model. We further simulated the spatiotemporal dynamics of forest C stocks and disturbance impacts in Guizhou for the period 1990–2016 using our customised model. Results shows that the total ecosystem C stock and C density, and C stocks in biomass, litter, dead wood, and soil in Guizhou increased continuously and significantly, while the soil C density decreased over the whole period, which could be attributed to deforestation history and climate change. The total ecosystem C stock increased from 1220 Tg C in 1990 to 1684 Tg C in 2016 at a rate of 18 Tg C yr−1, with significant enhancement in most areas, especially in the south and northwest. The total decrease in ecosystem C stock and C expenditure caused by disturbances reached 97.6 Tg C and 120.9 Tg C, respectively, but both represented significant decreasing trends owing to the decline of disturbed forest area during 1990–2016. Regeneration logging, deforestation for agriculture, and harvest logging caused the largest C stock decrease and C expenditure, while afforestation and natural expansion of forest contributed the largest increases in C stock. Conclusions: The forests in Guizhou were a net carbon sink under large-scale afforestation throughout the study period; Our customised CBM-CFS3 model can serve as a more effective and accurate method for estimating forest C stock and disturbance impacts in China and further enlightens model customisation to other areas. [ABSTRACT FROM AUTHOR]

Mountain forests are more prone to environmental predispositions (EPs) than submountain ones. While remote sensing of mountain forests enables instantaneous damage mapping, the investigation of the causes requires field data. However, a local field or regionally modeled environmental characteristics influence remote data evaluation differently. This study focused on the evaluation of EPs effects damaging mountain forests between various spatial resolutions during environmental change. The evaluation was divided into managed and natural forests in the Hrubý Jeseník Mts. (Czech Republic; 240–1491 m a.s.l.; 50.082°N, 17.231°E). Damage was assessed through the discrimination analysis of the normalised difference vegetation index (NDVI) by MODIS VI during alternating drought and flood periods 2003–2014. The local environmental influence was assessed using the discrimination function (DF) separability of forest damage in the training sets. The regional influence was assessed through map algebra estimated via the DF and a forest decline spatial model based on EPs from differences between risk growth conditions and biomass fuzzy sets. Management, EPs and soil influenced forest NDVI at different levels. The management afflicted the NDVI more than the EPs. The EPs afflicted the NDVI more than the soil groups. Strong winters and droughts had a greater influence on the NDVI than the flood events, with the winter of 2005/2006 inverting the DF direction, and the 2003 drought increasing differences in managed forest biomass and decreasing differences in natural forest biomasses. More than 50% of declining managed forests in the training sets occurred on Leptosols, Podzols and Histosols. On a regional scale, the soil influence was eliminated by multiple predispositions. The EPs influenced 96% of natural forest and 65% of managed forest, though managed forest damage was more evident. The mountain forest NDVI decline was dependent on both management and risk predispositions. [ABSTRACT FROM AUTHOR]

The Chinese government has made a strategic decision to reach 'carbon neutrality' before 2060. China's terrestrial ecosystem carbon sink is currently offsetting 7–15% of national anthropogenic emissions and has received widespread attention regarding its role in the 'carbon neutrality' strategy. We provide perspectives on this question by inferring from the fundamental principles of terrestrial ecosystem carbon cycles. We first elucidate the basic ecological theory that, over the long-term succession of ecosystem without regenerative disturbances, the carbon sink of a given ecosystem will inevitably approach zero as the ecosystem reaches its equilibrium state or climax. In this sense, we argue that the currently observed global terrestrial carbon sink largely emerges from the processes of carbon uptake and release of ecosystem responding to environmental changes and, as such, the carbon sink is never an intrinsic ecosystem function. We further elaborate on the long-term effects of atmospheric CO2 changes and afforestation on China's terrestrial carbon sink: the enhancement of the terrestrial carbon sink by the CO2 fertilization effect will diminish as the growth of the atmospheric CO2 slows down, or completely stops, depending on international efforts to combat climate change, and carbon sinks induced by ecological engineering, such as afforestation, will also decline as forest ecosystems become mature and reach their late-successional stage. We conclude that terrestrial ecosystems have nonetheless an important role to play to gain time for industrial emission reduction during the implementation of the 'carbon neutrality' strategy. In addition, science-based ecological engineering measures including afforestation and forest management could be used to elongate the time of ecosystem carbon sink service. We propose that the terrestrial carbon sink pathway should be optimized, by addressing the questions of 'when' and 'where' to plan afforestation projects, in order to effectively strengthen the terrestrial ecosystem carbon sink and maximize its contribution to the realization of the 'carbon neutrality' strategy. [ABSTRACT FROM AUTHOR]

Human impact on Central European forests dates back thousands of years. In this study we reanalyzed 36 published pollen data sets with robust chronologies from Polish Lowlands to determine the patterns of large-scale forest decline after the Migration Period (fourth to sixth century CE). The study revealed substantial heterogeneity in the old-growth forest decline patterns. Using new high-resolution studies, we could better understand the timing of this transition related to increasing economic development. After the Migration Period, forest expansion continued until the seventh to ninth centuries cal. CE, when the dawn of Slavic culture resulted in large-scale forest decline, especially in north-western and north-central Poland. Later, forest decline was recorded mainly in north-eastern Poland and was related to Prussian settlements, including activities associated with the Teutonic Order, as well as with new settlements from the fourteenth century. The composite picture shows a varied spatio-temporal forest loss and transition towards the present-day, human activity dominated landscapes. However, some sites, such as in north-eastern Poland, are characterized by a less abrupt critical transition. The pristine nature of the oak-hornbeam forest had already been destroyed in Early Medieval times (eighth to ninth centuries cal. CE) and the potential for recovery was largely lost. Our study has confirmed previous assumptions that the decline of hornbeam across the Polish Lowlands may be an early indicator of local settlement processes, preceding severe forest loss, and establishment of permanent agriculture. [ABSTRACT FROM AUTHOR]

A critical review of contemporary publications searching for the causes of the decline/dieback of dark-needled forests in the boreal and temperate zones over Northern Eurasia with an emphasis on the southern Siberian mountains is presented. Three groups of factors were considered: primary abiotic factors that weaken the tree defense mechanism (climate aridization, total ozone column, ultraviolet radiation (UV-B), dimming), anthropogenic factors (air pollution), and secondary biotic factors (invasive insect pests and phytopatogens that inhabit weakened trees, which finally leads to their decline/dieback). As there is no irrefutable evidence of the fatal impact of one particular factor, a synergic effect of some of them is possible against a certain climatic background. Further investigations are necessary to find out causes for the dark-needled forest decline/dieback in Northern Eurasia. [ABSTRACT FROM AUTHOR]

Extreme or recurrent drought events are the principal source of stress on forests, impairing their overall health. They result in financial losses for forest owners and ecosystem service losses for society. Most of the forested area in the Grand-Est region, France, is covered by European beech, which is projected to decline in the future due to repeated drought events driven by climate change. Diversification is a management option that can reduce the drought-induced risk of dieback. Two types of diversification were separately and jointly analyzed: a mixture of beech species with oak species and a mixture of different tree diameter classes. Two types of losses were also considered: financial and in terms of carbon storage under different occurrences of drought events derived from climate change scenarios. We combined an individual-based model of forest growth with a forest economic approach (i.e., land expectation value or LEV), which we adapted to the stochastic context by developing a doubly-weighted LEV. The maximization of the LEV made it possible to identify the most effective adaptation strategies in terms of timber revenue and carbon storage by means of three different carbon values (i.e., market value, shadow price, and social cost). The results showed that diversification increases timber returns and reduces the loss in timber volume due to the drought-induced risk of forest dieback. However, diversification negatively affects carbon storage. Integrating the value of carbon storage increases the value of the forest stand, but only a high carbon value has a significant economic impact. [ABSTRACT FROM AUTHOR]

While there is a global trend in kelp forests decline, sub-Antarctic Beagle Channel kelp ecosystems are among the most stable and extensive in the world, acting as a climatic refuge, indicating its high conservation value. Nevertheless, these coastal ecosystems are increasingly exposed to anthropogenic drivers that can affect kelp strategies and promote their replacement by turf. This study evaluated the urban impact of a coastal city in the Beagle Channel (Ushuaia, 54° S 68° W) on giant kelp (Macrocystis pyrifera) population dynamics. Seasonal samplings were conducted between 2020 and 2023 in two contrasting sites: an urban site directly exposed to Ushuaia pressures and a non-urban site. Our results indicate a reduction in both kelp adult density and kelp recruitment at the urban site. Here, high sediment inputs were the main factor affecting kelp recruitment, but higher density of potential grazers, and changes in the understory macroalgae assemblage were further observed. Morpho-functional composition and sediment trapped within the macroalgae suggest the prevalence of turf-forming algae dominating the urban site’s understory assemblage. If neglected, the decline in kelp recruitment rates and the replacement of the forest by turf could eventually lead to a local loss of this urban-influenced sub-Antarctic kelp forest. [ABSTRACT FROM AUTHOR]

Kelp forests are declining in many regions globally with climatic perturbations causing shifts to alternate communities and significant ecological and economic loss. Range edge populations are often at most risk and are often only sustained through localised areas of upwelling or on deeper reefs. Here we document the loss of kelp forests (Ecklonia radiata) from the Sultanate of Oman, the only confirmed northern hemisphere population of this species. Contemporary surveys failed to find any kelp in its only known historical northern hemisphere location, Sadah on the Dhofar coast. Genetic analyses of historical herbarium specimens from Oman confirmed the species to be E. radiata and revealed the lost population contained a common CO1 haplotype found across South Africa, Australia and New Zealand suggesting it once established through rapid colonisation throughout its range. However, the Omani population also contained a haplotype that is found nowhere else in the extant southern hemisphere distribution of E. radiata. The loss of the Oman population could be due to significant increases in the Arabian Sea temperature over the past 40 years punctuated by suppression of coastal upwelling. Climate-mediated warming is threatening the persistence of temperate species and precipitating loss of unique genetic diversity at lower latitudes. [ABSTRACT FROM AUTHOR]

The growth of past, present, and future forests was, is and will be affected by climate variability. This multifaceted relationship has been assessed in several regional studies, but spatially resolved, large-scale analyses are largely missing so far. Here we estimate recent changes in growth of 5800 beech trees (Fagus sylvatica L.) from 324 sites, representing the full geographic and climatic range of species. Future growth trends were predicted considering state-of-the-art climate scenarios. The validated models indicate growth declines across large region of the distribution in recent decades, and project severe future growth declines ranging from −20% to more than −50% by 2090, depending on the region and climate change scenario (i.e. CMIP6 SSP1-2.6 and SSP5-8.5). Forecasted forest productivity losses are most striking towards the southern distribution limit of Fagus sylvatica, in regions where persisting atmospheric high-pressure systems are expected to increase drought severity. The projected 21st century growth changes across Europe indicate serious ecological and economic consequences that require immediate forest adaptation. Tree ring data from a network of beech tree stands across Europe show evidence for a recent growth decline from 1986-2016 and project up to 50% growth reductions in some areas of Europe with future climate change. [ABSTRACT FROM AUTHOR]