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Copyright of Geology & Resources is the property of Geology & Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China's forest ecosystem plays a crucial role in carbon sequestration, serving as a cornerstone in China's journey toward achieving carbon neutrality by 2060. Yet, previous research primarily emphasized climate change's influence on forest carbon sequestration, neglecting tree species' suitable area changes. This study combinates the Lund–Potsdam–Jena model (LPJ) and the maximum entropy model (MaxENT) to reveal the coupling impacts of climate and tree species' suitable area changes on forest aboveground biomass carbon (ABC) in China. Key findings include the following: (1) China's forests are distributed unevenly, with the northeastern (temperate coniferous broad-leaved mixed forest, TCBMF), southwestern, and southeastern regions (subtropical evergreen broad-leaved forest, SEBF) as primary hubs. Notably, forest ABC rates in TCBMF exhibited a worrisome decline, whereas those in SEBF showed an increasing trend from 1993 to 2012 based on satellite observation and LPJ simulation. (2) Under different future scenarios, the forest ABC in TCBMF is projected to decline steadily from 2015 to 2060, with the SSP5-8.5 scenario recording the greatest decline (−4.6 Mg/ha/10a). Conversely, the forest ABC in SEBF is expected to increase under all scenarios (2015–2060), peaking at 1.3 Mg/ha/10a in SSP5-8.5. (3) Changes in forest ABC are highly attributed to climate and changes in tree species' highly suitable area. By 2060, the suitable area for Larix gmelinii in TCBMF will significantly reduce to a peak of 65.71 × 104 km2 under SSP5-8.5, while Schima superba Gardner & Champ and Camphora officinarum in SEBF will expand to peaks of 94.07 × 104 km2 and 104.22 × 104 km2, respectively. The geographic detector's results indicated that the climate and tree species' suitable area changes showed bi-variate and nonlinear enhanced effects on forest ABC change. These findings would offer effective strategies for achieving carbon neutrality. [ABSTRACT FROM AUTHOR]

The Mediterranean basin is an area particularly exposed to fire risk due to its climate and fire-prone vegetation. In recent decades, the frequency and intensity of wildfires increased, leading to negative effects on forests, such as a decrease in tree growth or an increase in tree mortality, producing a relevant loss of carbon sequestration ecosystem service. This study of the impacts of fires on forests is fundamental for planning adequate forest management strategies aimed at recovering and restoring the affected areas. In this framework, our research delves into the effects of a forest fire that, in 2017, affected a forest of black pine (Pinus nigra Arnold) in Central Italy. Combining satellite and terrestrial analyses, this study evaluated the impact of the fire on tree growth, water use efficiency and carbon sequestration capacity. Our findings highlight the importance of using remote sensing for the accurate identification of fire-affected areas and precise planning of ground-based activities. However, the integration of satellite data with forest surveys and sampling has proven crucial for a detailed understanding of fire's effects on trees. Dendrochronology and stable isotopes have revealed the post-fire growth decline and altered water usage of defoliated trees. Furthermore, the quantification of CO2 sequestration highlighted a significant reduction in carbon uptake by damaged trees, with severe implications for this ecosystem service. [ABSTRACT FROM AUTHOR]

The normalized difference vegetation index (NDVI) and tree-ring parameters are commonly used indicators in the research on forest ecology and responses to climate change. This paper compiles and analyzes the literature on vegetation index research on the basis of tree-ring information in the past 20 years and provides an overview of the relationship between tree-ring parameters and NDVI, as well as NDVI reconstruction. The research on the vegetation index based on tree-ring data is mainly concentrated in the middle and high latitudes, and relatively few studies are concentrated in the low latitudes. The tree-ring parameters have a strong correlation with the NDVI in the summer. In terms of tree-ring reconstruction NDVI, Sabina przewalskii is the tree with the longest reconstruction sequence so far, and the tree-ring width is the main proxy index. In addition, combining tree rings with the NDVI is useful for assessing forest decline, quantifying the forest response to drought, and monitoring forest productivity. In the future, it is necessary to consider a variety of environmental factors to find the optimal model construction parameters and carry out research on the climate response of forest tree growth and the reconstruction of the historical sequence of the vegetation index at large spatial scales. [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]

This article explores the relationship between tree water deficit (TWD) and stem radial growth in mixed forests. The study examines the effects of neighborhood composition and functional traits on TWD and stem radial growth using data from a tree diversity manipulation experiment in subtropical China. The results suggest that functional dissimilarity among trees at the neighborhood scale can mitigate water deficit and promote stem radial growth. The findings highlight the importance of considering functional diversity and species interactions in forest management practices. [Extracted from the article]

Copyright of Forestry Chronicle is the property of Canadian Institute of Forestry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Compound drought‐heatwave (CDHW) events threaten ecosystem productivity and are often characterized by low soil moisture (SM) and high vapor pressure deficit (VPD). However, the relative roles of SM and VPD in constraining forest productivity during CDHWs remain controversial. In the summer of 2022, China experienced a record‐breaking CDHW event (DH2022). Here, we applied satellite remote‐sensing data and meteorological data, and machine‐learning techniques to quantify the individual contributions of SM and VPD to forest productivity variations and investigate their interactions during the development of DH2022. The results reveal that SM, rather than VPD, dominates the forest productivity decline during DH2022. We identified a possible critical tipping point of SM below which forest productivity would quickly decline with the decreasing SM. Furthermore, we illuminated the evolution of SM, VPD, evapotranspiration, forest productivity, and their interactions throughout DH2022. Our findings broaden the understanding of forest response to extreme CDHWs at the ecosystem scale. Plain Language Summary: Low soil moisture (SM) and high vapor pressure deficit (VPD) are widely recognized as the dominant drivers of forest productivity decline during compound drought‐heatwave (CDHW) events. In the summer of 2022, a record‐breaking CDHW (DH2022) struck China. In this study, we decoupled the respective impacts of SM and VPD in determining forest productivity decline during DH2022. We found that during DH2022, SM, rather than VPD, is the dominant driver of forest productivity decline, and once SM decreases below a certain threshold, forest productivity would decline sharply. We illuminated the evolution of SM, VPD, evapotranspiration, forest productivity, and their interactions throughout DH2022. Our findings promote the understanding of forest response to extreme CDHWs at the ecosystem scale and thus potentially improve terrestrial ecosystem models' ability to evaluate and predict the impacts of CDHWs. Key Points: Soil moisture (SM), rather than vapor pressure deficit, dominates the forest productivity decline in the 2022 China compound drought‐heatwave eventForest productivity would decline sharply once SM drops below a certain threshold during extreme compound drought‐heatwave eventsEvolution of the 2022 China compound drought‐heatwave event and its impacts on forests were illuminated [ABSTRACT FROM AUTHOR]

The ecosystem service value (ESV) gradient-evolution pattern of a river basin's land and water-intertwined zones has a variety of ecosystem service values, such as biodiversity conservation, water conservation, water purification, etc. The study of the ecosystem service value (ESV) gradient-evolution pattern of a river basin's land and water-intertwined zones will provide a scientific basis for the construction and protection of the ecological security pattern of the river basins. In this study, we combined the unit area equivalent factor method and geographically weighted regression (GWR) model to classify and analyze the gradient change pattern of ESV upstream, downstream, and along the river of the Guangdong mainstream section of the Xijiang River in China, and the conclusions are as follows: (1) The corresponding ESV share of each land use type was in the following order: water bodies > broad-leaved forest > artificial wetland > scrub > paddy field > coniferous forest > natural wetland > grassland. The level of each type of ESV does not depend entirely on the size of the area but is determined by the ecosystem service functions it can provide and the level of ESV per unit area; (2) the relationship between land use types along both sides of the river in the Guangdong section of the Xijiang River Basin shows a tendency to shift from water ecosystems to terrestrial ecosystems, and the ESV gradually decreases with the increase in distance from the water. (3) The upstream to the downstream area showed a trend of changing from terrestrial ecosystems to aquatic ecosystems, such as broad-leaved forests, scrublands, water bodies, artificial wetlands, etc., and the mean land ESV showed a general trend of undulating change and decline with the reduction in the distance from the downstream area. (4) Natural factors, such as the topography and geomorphology of the basin and the socio-economic factors of power consumption, influence the spatial distribution characteristics of the ESV in the region; among them, socio-economic factors, such as total power consumption, industrial exhaust gas emissions, industrial wastewater emissions, etc., in the economically developed areas of the Xijiang River Basin are the determinants of the changes in ESV, which are generated by human living and production activities, and these indirectly affect the magnitude of the ESV by influencing the factors of temperature and gas. [ABSTRACT FROM AUTHOR]

While some agricultural landscapes can support wildlife in the short term, it is uncertain how well they can truly sustain wildlife populations. To compare population trends in different production systems, we sampled birds along 48 transects in mature forests, diversified farms, and intensive farms across Costa Rica from 2000 to 2017. To assess how land use influenced population trends in the 349 resident and 80 migratory species with sufficient data, we developed population models. We found, first, that 23% of species were stable in all three land use types, with the rest almost evenly split between increasing and decreasing populations. Second, in forest habitats, a slightly higher fraction was declining: 62% of the 164 species undergoing long-term population changes; nearly half of these declines occurred in forest-affiliated invertivores. Third, in diversified farms, 49% of the 230 species with population changes were declining, with 60% of these declines occurring in agriculture-affiliated species. In contrast, 51% of the species with population changes on diversified farms showed increases, primarily in forest-affiliated invertivores and frugivores. In intensive farms, 153 species showed population changes, also with similar proportions of species increasing (50%) and decreasing (50%). Declines were concentrated in agriculture-affiliated invertivores and forest-affiliated frugivores; increases occurred in many large, omnivorous species. Our findings paint a complex picture but clearly indicate that diversified farming helps sustain populations of diverse, forest-affiliated species. Despite not fully offsetting losses in forest habitats, diversified farming practices help sustain wildlife in a critical time, before possible transformation to nature-positive policies and practices. [ABSTRACT FROM AUTHOR]

Tropical montane cloud forests (TMCFs) are expected to experience more frequent and prolonged droughts over the coming century, yet understanding of TCMF tree responses to moisture stress remains weak compared with the lowland tropics. We simulated a severe drought in a throughfall reduction experiment (TFR) for 2 years in a Peruvian TCMF and evaluated the physiological responses of several dominant species (Clusia flaviflora Engl. Weinmannia bangii (Rusby) Engl. Weinmannia crassifolia Ruiz & Pav. and Prunus integrifolia (C. Presl) Walp). Measurements were taken of (i) sap flow; (ii) diurnal cycles of stem shrinkage, stem moisture variation and water-use; and (iii) intrinsic water-use efficiency (iWUE) estimated from foliar δ13C. In W. bangii , we used dendrometers and volumetric water content (VWC) sensors to quantify daily cycles of stem water storage. In 2 years of sap flow (Js) data, we found a threshold response of water use to vapor pressure deficit vapor pressure deficit (VPD) > 1.07 kPa independent of treatment, though control trees used more soil water than the treatment trees. The daily decline in water use in the TFR trees was associated with a strong reduction in both morning and afternoon Js rates at a given VPD. Soil moisture also affected the hysteresis strength between Js and VPD. Reduced hysteresis under moisture stress implies that TMCFs are strongly dependent on shallow soil water. Additionally, we suggest that hysteresis can serve as a sensitive indicator of environmental constraints on plant function. Finally, 6 months into the experiment, the TFR treatment significantly increased iWUE in all study species. Our results highlight the conservative behavior of TMCF tree water use under severe soil drought and elucidate physiological thresholds related to VPD and its interaction with soil moisture. The observed strongly isohydric response likely incurs a cost to the carbon balance of the tree and reduces overall ecosystem carbon uptake. [ABSTRACT FROM AUTHOR]

Two coastal areas located on the North-Western side of Corsica Island have been investigated to reconstruct their Mid- to Late-Holocene landscape evolution together with the history of human occupation. Particular attention has been paid to the study of shoreline migration and vegetation history alongside land-use. Three boreholes were drilled to a maximum depth of 4.20 m and laboratory work comprised the identification of molluscs and pollen/NPPs as well as sedimentological analyses. Chronostratigraphy is based on a series of 18 radiocarbon datings and enabled to reconstruct the environments in the Fangu Estuary to the north of the World Heritage site over the last six millennia, and over the last four millennia on the Girolata coastal plain to the south. Palaeogeographic reconstruction of shoreline mobility is established for each site based on borehole chronostratigraphy analysis. In addition, two original pollen and NPPs diagrams have been established for the Girolata and Fangu sites. These reveal that anthropogenic activities began to significantly impact local vegetation cover ca. 2500 years BP at Girolata, and ca. 2000 years BP at Fangu. Of particular interest, our work records the first complete pollen sequence in Corsica for Roman times at Girolata: first, the exploitation of cereals, grapevines and the development of husbandry is observed during the Roman Republic (500 BCE–0), followed by the almost exclusive cultivation of Olea sp. during the Roman Empire (0–500 CE). Following this, and using other regional pollen studies obtained for NW Corsica, we propose a regional evolution of the complex human-environment interactions for the last six millennia. Our results reveal a peak of regional forest decline (the most intense event recorded for the Late-Holocene) from the 11th to the 16th centuries CE which can be attributed to the exploitation of wood resources during the Pisan and Genoese dominations of the island. [ABSTRACT FROM AUTHOR]

Pollen analysis of a marine core collected in the Gulf of S. Eufemia (Tyrrhenian Calabria, Italy) allowed reconstructing the regional changes in vegetation and land use over the last 5000 years. Pollen diagram zonation through Constrained Cluster Analysis highlighted three compositional zones whose boundaries mark the major changes that affected the vegetation structure. A dense forest cover with a few signs of human activities characterized the wide pollen source area from 5055 to 2700 BP (Zone 1). In this period, the Pre-Protohistoric communities were mainly concentrated on the Tropea Promontory where they had a significant local impact. Minor forest rarefactions at 5000–4800 BP, ca. 4400–4000 BP, ca. 3450–3150 BP were correlated to phases of climatic shifts toward aridity. From 2700 to 2000 BP (Zone 2a), a longer and more incisive period of forest decline was connected to a time of aridity that favored the intense activities of an increasing anthropogenic pressure. Indeed, important urban centers developed in the area during the Greek and Roman colonization. Diffuse deforestation and cultivation occurred from 790 BP (Zone 3), enhancing soil erosion and fluvial discharge as testified by the sudden increase in sedimentation rates. This disruption of the slope morphodynamics was connected to the collapse of territorial management following the end of the Western Roman Empire. Compositional Data Analysis, applied to a simplified pollen dataset, highlighted both a negative correlation between Abies and Fagus and a close similarity between the AP/NAP curve and the Axis 1 scores of the Relative Variation Biplot. [ABSTRACT FROM AUTHOR]

The proliferation in mesoherbivore numbers and their associated impact on the detrital ground cover were deemed responsible for the decline in fossorial herpetofaunal densities in Ndumo Game Reserve during the early 2000s. Subsequent increased poaching pressure and wildlife declines allowed the reassessment of the sand forest fossorial herpetofaunal community to test this assumption. We found no significant increase in the two most abundant soil‐living reptiles despite significant mesoherbivore declines. This may indicate that either fossorial herpetofaunal numbers increase very slowly, or that the initial two survey methodologies were incomparable. Alternatively, some unknown environmental factor may be suppressing populations or the survey results are not representative of the fossorial herpetofaunal community. [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]

The determination of indigenous peoples' rights to customary forests has been regulated and recognized in the State Constitution of the Republic of Indonesia of 1945 and Law Number 5 of 1960 concerning Basic Provisions of Agrarian Principles (UUPA) and the Constitutional Court Decision of the Republic of Indonesia Number 35 of 2012, but until now there are still many government activities and companies holding Forest Concession Rights Permits that claim customary forests as state forests. This has resulted in conflicts in customary forest management. This study aims to analyze the causes of conflicts over customary forest land conversion in the Gowa Regency and analyze the legal consequences of conflicts in the Gowa Regency customary forest areas. This research uses qualitative research with a descriptive type. By conducting in-depth interviews with the Gowa District Forestry Service, Customary Leaders and company leaders holding Forest Concession Rights Permits. The results showed that there was a conflict in customary forest management in Gowa Regency, caused by each party, both local governments, Forest Concession Rights (HPH) holders and indigenous peoples claiming that they did not clearly understand the meaning contained in the legislation and also the Gowa Regency Regional Regulation which recognized the rights of indigenous peoples only limited to recognition but in fact, deprived indigenous peoples of their rights in the form of forests, as a result of the legal occupation of customary forest areas in Gowa Regency by local governments and HPH Permit Holders, flooding and erosion due to massive deforestation and residents around the forest are declining health level (Poor). For this reason, the local government is expected to immediately make optimal efforts to empower indigenous peoples in the form of forests so that they can improve their welfare and not give permission to companies to manage customary forests in the Gowa Regency so that conflicts are not prolonged. [ABSTRACT FROM AUTHOR]

In declining broadleaf forests in western Ukraine, several Phytophthora species including P. plurivora, P. bilorbang, P. polonica, P. gonapodyides and P. cactorum were recovered using soil baiting assays and identified using morphological and molecular methods. Pathogenicity tests of selected isolates were performed on black alder (Alnus glutinosa (L.) Gaerth.) and silver birch (Betula pendula Roth.) to assess susceptibility of these two tree species to the newly detected Phytophthora species. Phytophthora plurivora, P. bilorbang and P. polonica showed higher pathogenicity in both alder and birch compared to the other tested Phytophthora species. [ABSTRACT FROM AUTHOR]

This article analysed the 25–30 years of growth of dipterocarps forests that were logged under the Selective Management System (SMS) at three sites in Peninsular Malaysia to understand how management regimes affected forest stem density and basal area. The management regimes were (1) unlogged, (2) moderately logged forests that logged all dipterocarps ≥ 65 cm diameter at breast height (dbh) and all non-dipterocarps ≥ 60 cm dbh, and (3) intensely logged forests that logged all dipterocarps ≥ 50 cm dbh and nondipterocarps ≥ 45 cm dbh. The intensely logged regime is similar to the SMS practices in Peninsular Malaysia. This result showed that one-year post-logging, there was no difference in the total stem density and basal area between forests logged according to the two management regimes. Forest stem density decreased over time in all management regimes, significantly greater in unlogged forests (-15.1 stems/ha/yr, confidence interval (CI): -16.9 to -13.3). This decline in stem density reflected that mortality exceeded recruitment in all management regimes. Despite the consistent decline of forest stem density, the basal area increased over time, and the rate of increase in the intensely logged forest (0.22 m² /ha/yr, CI: 0.19 to 0.25)was significantly greater than the other management regimes. Our study showed that 30 years post-logging, the effect of selective logging remained evident. Both logged forest stem density and the basal area did not recover to that of unlogged forests, indicating the importance of enrichment planting and extending the cutting cycles beyond 30 years for the sustainability of dipterocarps forests. [ABSTRACT FROM AUTHOR]

Keywords: isotope labelling; Pinus; Quercus; sap flow; water status regulation; water storage; water-use strategies EN isotope labelling Pinus Quercus sap flow water status regulation water storage water-use strategies 1285 1289 5 08/16/23 20230801 NES 230801 This scientific commentary refers to 'Contrasting stem water uptake and storage dynamics of water-saver and water-spender species during drought and recovery' by [23] (doi: 10.1093/treephys/tpad032). Google Scholar Crossref Search ADS PubMed WorldCat 39 Tyree MT, Sperry JS (1989) Vulnerability of xylem to cavitation and embolism. Google Scholar Crossref Search ADS PubMed WorldCat 15 Jupa R, Plavcová L, Gloser V, Jansen S (2016) Linking xylem water storage with anatomical parameters in five temperate tree species. Google Scholar Crossref Search ADS PubMed WorldCat 16 Kannenberg SA, Guo JS, Novick KA, Anderegg WRL, Feng X, Kennedy D, Konings AG, Martínez-Vilalta J, Matheny AM (2022) Opportunities, challenges and pitfalls in characterizing plant water-use strategies. [Extracted from the article]

Bark beetle disturbances are a critical event in the life cycle of Norway spruce forests. However, our knowledge of their effects on ectomycorrhizal fungi (EMF), which play a key role in forest productivity and nutrient cycling, is still incomplete. Special attention has been paid to the dynamics and diversity of EMF communities in managed forests, but studies dealing with disturbed natural stands are underrepresented. We conducted a study in an unmanaged natural spruce forest in the Bohemian Forest (Czech Republic), which suffered severe forest dieback caused by bark beetle. Approximately a decade after the disturbance, the character of the forest structure in the study area (∼60 ha, 41 study plots) ranged from sites with open canopy and sparse tree cover to areas with dense spruce regeneration to patches of closed-canopy forest. We found that relative EMF abundance in soils was positively related to surviving tree and regeneration density. The number of surviving trees also positively affected species EMF richness and tended to support preservation of late-successional EMF species. Our results suggest that trees that survive bark beetle disturbance are key for the fate of the EMF community in natural forests. [ABSTRACT FROM AUTHOR]

In recent years, increasing tree diebacks and mortality in some forests, particularly in forest parks, created a need amongst forest managers to find effective methods to gather information about the rate of dieback and mortality and their reasons. High-quality air and space-born remote sensing data has established as an alternative to field surveys for certain inventory tasks. This study used high-quality UltraCam-Xp and UAV drone images from 2016 and 2021 to map tree dieback and mortality in Daland Forest Park, Golestan Province, Iran. High-quality ortho mosaics and Digital Surface Models (DSMs) were generated from UltraCam (2016) and UAV (2021) images. The images were then classified through object-based classification by Nearest Neighbor (NN), Support Vector Machine (SVM), and Bayes algorithms using various input data sets including spectral bands, Canopy Height Model (CHM), vegetation indices, and texture analysis features. Our results indicate that the Bayes algorithm is more precise in mapping tree dieback for the two time steps compared to other algorithms. The best tree dieback map on UltraCam images was obtained using the spectral bands with CHM, texture analysis features, and vegetation indices. This combination resulted in an overall accuracy of 91.20% and a Kappa coefficient of 0.88. It was also found that combining the UAV main bands with CHM and texture features did produce a high-accuracy map with an overall accuracy of 88.46% and a Kappa coefficient of 0.84. Change detection analysis of tree dieback showed that between 2016 and 2021, the number of healthy trees decreased, and the number of gaps and open areas increased in the study area. We conclude that UltraCam and UAV photographs can serve to identify and map tree dieback and dead trees with good accuracies and can hence support forest health monitoring. [ABSTRACT FROM AUTHOR]

The endangered javan gibbon (Hylobates moloch) has been threaten by massive habitat loss and fragmentation in Java. The survival of the second largest population which inhabited unprotected Dieng mountains faced greater risk to habitat conversion and fragmentation. The landscape-level habitat monitoring using spatiotemporal quantification is crucial as a baseline data for javan gibbon conservation. Here, the land-use and land-cover (LULC) change of the Javan gibbon habitat during 1994-2009-2021 and its fragmentation in the Dieng mountains were quantified. This study revealed there were no significant decline in the total of forest. However, its quality was degraded in the interior of forest block. The forest has more fragmented from large patches into smaller patches and increased forest edge. The higher fragmentation happened in the areas that traversed by road. Six suitable forest blocks were identified with varying level of connectivity. Protection and restoration both in the forest and in the interior forest is immediate need, especially in the main forest block. The extra effort is also crucial in the connected forest but traversed by road. The blocks which closely isolated by road could be potentially reconnected by artificial canopy bridge, while the other distantly isolated block might need habitat restoration for corridor. [ABSTRACT FROM AUTHOR]

Pine wilt disease (PWD) is a highly destructive disease in forest ecosystems, resulting in extensive forest decline and substantial economic losses. As soil pH plays a critical role in soil microbial activity and significantly impacts the prevalence and severity of diseases, we conducted an experiment to regulate soil pH for alleviating PWD in a black pine (Pinus thunbergii) forest. The result reveals that: (1) The pH of the soil under a P. thunbergii forest was 5.19 ± 0.40, which was significantly lower than that of soils under other vegetation types at 8.53 ± 0.44. (2) Finely ground shell powder (F-SP) was the optimal size for long-term and efficient regulation, but quicklime (QL) exhibited the strongest efficacy in raising soil pH, followed by F-SP and plant ash. The regulation effect strengthened with the dosage amount. (3) In the situ experiments, part of symptomatic black pine in F-SP or QL plots were apparently improved and converted to asymptomatic trees separately by 15.9% and 5.4%. Applying F-SP can alleviate PWD in a sustainable way. This paper presents the first investigation to assess the effects of regulating soil pH for controlling PWD. It holds significant practical value for the rational planning and the sustainable development of artificial forests in coastal regions. [ABSTRACT FROM AUTHOR]

IntroductionForests in the Mediterranean basin are currently in decline. Their resilience has been eroded as a result of climate change and anthropogenic impacts, making them vulnerable to increasingly frequent episodes of drought, fire and the spread of pests and diseases. The impact of these natural and anthropogenic events on soil biodiversity is of particular concern, as the soil fungal community plays a key role in ecosystem homeostasis.Objectives and methodsIn order to analyse the relationship between soil health status and fungal diversity, soil samples were collected from declining Mediterranean forests of Castanea sativa (chestnut), Quercus ilex (holm oak), Quercus suber (cork oak) and Quercus pyrenaica (Pyrenean oak). A metabarcoding study was carried out by sequencing the ITS genomic region.ResultsA total of 674 fungal genera were found. It has not been possible to explain the differences in health status from the fungal genera found exclusively on declining forest soils, as none of them have been described as pathogenic. Healthy chestnut soils were characterized by a high alpha diversity and a higher abundance of the genus Metarhizium. No differentially abundant genera were found in any of the other forest species tested. Declining chestnut soils harbored more abundance of ectomycorrhizae and soil saprotrophs than healthy samples. Ectomycorrhizae were the dominant lifestyle in all oak species regardless of health status, whereas arbuscular mycorrhizae were preferentially found in declining cork oak soils.DiscussionThis work highlights the resilience of fungal communities of soil against decline and highlights the need to further investigate its relationship with the forest’s ability to cope with the challenges of climate change.

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]

Background and Aims In dryland ecosystems, conifer species are threatened by more frequent and severe droughts, which can push species beyond their physiological limits. Adequate seedling establishment will be critical for future resilience to global change. We used a common garden glasshouse experiment to determine how seedling functional trait expression and plasticity varied among seed sources in response to a gradient of water availability, focusing on a foundational dryland tree species of the western USA, Pinus monophylla. We hypothesized that the expression of growth-related seedling traits would show patterns consistent with local adaptation, given clinal variation among seed source environments. Methods We collected P. monophylla seeds from 23 sites distributed across rangewide gradients of aridity and seasonal moisture availability. A total of 3320 seedlings were propagated with four watering treatments representing progressively decreasing water availability. Above- and below-ground growth-related traits of first-year seedlings were measured. Trait values and trait plasticity, here representing the degree of variation among watering treatments, were modelled as a function of watering treatment and environmental conditions at the seed source locations (i.e. water availability, precipitation seasonality). Key Results We found that, under all treatments, seedlings from more arid climates had larger above- and below-ground biomass compared to seedlings from sites experiencing lower growing-season water limitation, even after accounting for differences in seed size. Additionally, trait plasticity in response to watering treatments was greatest for seedlings from summer-wet sites that experience periodic monsoonal rain events. Conclusions Our results show that P. monophylla seedlings respond to drought through plasticity in multiple traits, but variation in trait responses suggests that different populations are likely to respond uniquely to changes in local climate. Such trait diversity will probably influence the potential for future seedling recruitment in woodlands that are projected to experience extensive drought-related tree mortality. [ABSTRACT FROM AUTHOR]

Ongoing climatic change is threatening the survival of drought-sensitive tree species, such as silver fir (Abies alba). Drought-induced dieback had been previously explored in this conifer, although the role played by tree-level genetic diversity and its relationship with growth patterns and soil microsite conditions remained elusive. We used double digest restriction-site-associated DNA sequencing (ddRADseq) to describe different genetic characteristics of five silver fir forests in the Spanish Pyrenees, including declining and non-declining trees. Single nucleotide polymorphisms (SNPs) were used to investigate the relationships between genetics, dieback, intraspecific trait variation (functional dendrophenotypic traits and leaf traits), local bioclimatic conditions, and rhizosphere soil properties. While there were no noticeable genetic differences between declining and non-declining trees, genome–environment associations with selection signatures were abundant, suggesting a strong influence of climate, soil physicochemical properties, and soil microbial diversity on local adaptation. These results provide novel insights into how genetics and diverse environmental factors are interrelated and highlight the need to incorporate genetic data into silver fir forest dieback studies to gain a better understanding of local adaptation. [ABSTRACT FROM AUTHOR]

Spatially explicit reconstruction of historical land cover change is a prerequisite for a more comprehensive understanding of environmental changes. Anthropogenic activities have dramatically altered the land cover of the conterminous United States (CONUS), encroaching heavily on the primary vegetation. However, few datasets exist that depict the historical trajectory of forest and grassland cover changes in CONUS over the last millennium, and previous efforts have only focused on reconstructions for the last four centuries. By integrating remote sensing-derived land use/cover change (LUCC) data and potential vegetation data, we determined the potential extent of natural forest (PENF) and grassland (PENG) in CONUS. Based on a qualitative analysis of the trends and driving forces of forest and grassland changes, we devised a method of subtracting reconstructed historical cropland (1000–2000 AD) and built-up land (1850–2000 AD) from PENG and PENF to reconstruct a 5 min × 5 min grid dataset of forest and grassland cover at 13 time-points over the past millennium. The results showed that forest and grassland cover in CONUS underwent a slow decline (1000–1600 AD), an accelerated decline (1600–1800 AD), a dramatic decline (1800–1950 AD), and finally, a recovery (1950–2000 AD) over the study period. The modelled forest fraction decreased from 49% in 1000 AD to 33% in 2000 AD, representing a 32% area reduction, whereas the modelled grassland fraction decreased from 37% to 22%, representing a 42% area reduction. The reduction occurred primarily in the last 200 years, with forest and grassland reductions accounting for 86% and 97% of the total reduction over the millennium, respectively. Spatially, more than 80% of the land was originally covered by forests and grasslands, and the loss occurred mainly in the eastern CONUS and Great Plains over the past millennium. After the 1930s, farmland abandonment began in central and eastern CONUS, simultaneously with environmental protection laws. Federal government regeneration programs for forest and grassland resources and the Shelterbelt Project all contributed to a slowdown in forest and grassland decline and recovery in cover. [ABSTRACT FROM AUTHOR]

In this paper, satellite imagery is classified into four categories using the fuzzy c-means algorithm of the Indian Sundarbans due to its forest density changes. The categories are dense forest, sparse forest, water bodies, and wetlands. The study reveals that net forest areas declined by 3.75% from 932 km2 in 1975 to 847 km2 in 2018 and the rate of deforestation was 1.96 km2 year−1. The correlation statistic shows that the deforested areas were converted to wetland and water bodies. The results of the forest canopy density (FCD) model show that areas, with canopy density of 60–100% gradually declined from 42% (939 km2) in 1975 to 36% (814 km2) in 2018. Moreover, we also observed that maximum canopy density was >80% in 1990 and 60–80% in 1975. The results of the forest fragmentation model show that forest patch and edge areas progressively increased by 253% and 28%, respectively, while perforated forest areas slowly decreased with 11%. We find that most forest fragmentation happened in patch, edge, perforated, and core forest with an area >4 km2. Therefore, this study may be helpful in monitoring land cover changes of the Indian Sundarbans for sustainable mangrove forests. [ABSTRACT FROM AUTHOR]

Between 1954 and the mid-1980s, about 50,000 ha of native montane rainforest on the island of Hawai'i experienced a decline in canopy trees ("'ōhi'a dieback"), leading to great concern about the future of Hawai'i's rainforests. Dieback symptoms particularly affected the dominant tree species, the endemic Metrosideros polymorpha. Early hypotheses postulated that the forest decline was caused by a virulent pathogen or a combination of biotic disease and pest agents. This was ruled out after a decade of intensive disease research in the 1970s. Instead, it turned out that dieback patterns were significantly related to the physical environment, particularly the slope, topography, relative position on the hill slope, annual rainfall, and the type of substrate. Thus, an alternative hypothesis proposed that dieback is initiated by climate anomalies that manifest through soil moisture regimes under certain conditions of forest stand demography. Ironically, scientific perception of this interdisciplinary groundbreaking research that stimulated a global perspective on forest decline vanished while the awareness of climate change and its potential impact on the world's forests started to grow, rapidly becoming a major focus of research in recent years. In this paper, we reinforce memory of the world's first complex discussion on the natural causes of forest dieback as a showcase for the complexity of modern forest mortality research. This case demonstrates the need to rigorously identify, quantify, and fully understand all drivers of tree mortality to realistically project future climate-driven and other risks to forest ecosystem functions and services. Moreover, we summarize recent findings on forest mortality and climate change in the Pacific islands and beyond. [ABSTRACT FROM AUTHOR]

Old growth forests are declining globally, threatening dependent wildlife. Many arboreal old‐growth obligates, such as the threatened red tree vole, are difficult to monitor for changes in habitat occupancy, and abundance. Yet, conservation planning relies on this information to prevent population declines. We integrated a range of species, habitat, and landscape change information to develop a dynamic habitat‐population model. The spatial individual‐based model simulated dynamic patterns of occupancy that responded to annual habitat maps, describing 36 years of observed change. We simulated population dynamics and local movement to characterize changes in occupancy and abundance, and the capacity of remaining habitat to support red tree voles. Red tree vole redistribution patterns strongly corresponded to wildfire footprints and timber extraction locations. Population strongholds are likely to exist in clumped pockets of old‐growth forest that were unaffected by wildfire and in protected old forest reserves. However, the exact number and locations of local clusters remain uncertain. Simulated population losses occurred at different paces in different places, underscoring the need for recurring evaluation of population changes with field occupancy surveys and modeled evaluations that can anticipate potential connectivity and extirpation thresholds. This modeling approach was effective at leveraging existing information for a data‐light species to assess how historical changes to the quantity, quality, and configuration of habitat likely influenced the potential landscape capacity, species abundance, and distribution. Dynamic individual‐based modeling can benefit conservation planning for red tree vole and other reclusive forest species by providing biologically nuanced assessments of abundance and distribution. Such models can also project the long‐term benefits and impacts of spatially explicit land management plans. [ABSTRACT FROM AUTHOR]

We compare Holocene tree cover changes in Europe derived from a transient Earth system model simulation (Max Planck Institute Earth System Model – MPI-ESM1.2, including the land surface and dynamic vegetation model JSBACH) with high-spatial-resolution time slice simulations performed in the dynamic vegetation model LPJ-GUESS (Lund–Potsdam–Jena General Ecosystem Simulator) and pollen-based quantitative reconstructions of tree cover based on the REVEALS (Regional Estimates of Vegetation Abundance from Large Sites) model. The dynamic vegetation models and REVEALS agree with respect to the general temporal trends in tree cover for most parts of Europe, with a large tree cover during the mid-Holocene and a substantially smaller tree cover closer to the present time. However, the decrease in tree cover in REVEALS starts much earlier than in the models, indicating much earlier anthropogenic deforestation than the prescribed land use in the models. While LPJ-GUESS generally overestimates tree cover compared to the reconstructions, MPI-ESM indicates lower percentages of tree cover than REVEALS, particularly in central Europe and the British Isles. A comparison of the simulated climate with chironomid-based climate reconstructions reveals that model–data mismatches in tree cover are in most cases not driven by biases in the climate. Instead, sensitivity experiments indicate that the model results strongly depend on the tuning of the models regarding natural disturbance regimes (e.g. fire and wind throw). The frequency and strength of disturbances are – like most of the parameters in the vegetation models – static and calibrated to modern conditions. However, these parameter values may not be valid for past climate and vegetation states totally different from today's. In particular, the mid-Holocene natural forests were probably more stable and less sensitive to disturbances than present-day forests that are heavily altered by human interventions. Our analysis highlights the fact that such model settings are inappropriate for paleo-simulations and complicate model–data comparisons with additional challenges. Moreover, our study suggests that land use is the main driver of forest decline in Europe during the mid-Holocene and late Holocene. [ABSTRACT FROM AUTHOR]

Unpredictable drought–heatwave events occur frequently worldwide, causing low water availability (drought) and high temperatures (hot), with consequences for forest decline and mortality. Our knowledge of the potential instantaneous reactions and subsequent recovery of water-related physiological processes and vegetation indices in hot drought events remains unclear. Here, we investigated how the 2022 summer drought–heatwave event in the subtropical regions of China affected hydraulic traits and NDVI values in the forests of four common subtropical tree species. During the hot drought, the NDVI values of all four forests decreased (−31%~−23%), accompanied by leaf scorch and tree crown dieback. Among the four species, a hot drought event caused an instantaneous descent in hydraulic conductivity (Ks, −72%~−31%), stomatal conductance (gs, −94%~−50%), and midday water potential (−40%~−169%), with severe drought-induced stem xylem embolism. A trade-off was found between resistance and resilience in hot-drought-induced hydraulic dysfunction, as species with lower declines in Ks and gs during the hot drought had a shorter recovery in the post-stress phase. This study highlights that the 2022 hot drought event had severe negative instantaneous impacts on the forests of four subtropical tree species, which were reflected both in water-related physiological processes in the field and in remote sensing data from satellites. [ABSTRACT FROM AUTHOR]

After the transformation of counties in urban suburbs into districts, the rapid urbanization and industrialization process in China's developed regions had a huge impact on the spatial distribution and equity of the suburban forest ecological functions. Accurately describing this impact could provide an important reference for the construction of suburban forest engineering and for ecological environmental planning. Jiangning District of Nanjing City, China, was selected as the research area, while the forest resource planning and design survey data in 2007 and 2017, together with the demographic data of the study area, were collected as the main information sources. Following the establishment of the forest ecological function evaluation indicators and the analysis of the spatial change of the forest ecological functions, the Gini coefficient was calculated to analyze the changes of the regional ecological function equality. The results showed that: (1) Compared with 2007, the proportion of areas with low forest ecological functions (abbreviated as FEF) in the study area in 2017 showed a downward trend, and the proportion of areas with medium and high FEF showed an increasing trend; (2) Compared with 2007, the forest landscape in the study area in 2017 was severely fragmented, the spatial aggregation of the FEF showed a significant decline, and the FEF developed towards a direction of spatially balanced distribution; (3) During 2007–2017, the sub-compartments with high-value FEF in the study area (hot spots) shifted to the northwest, where the economy was developed and the population density was higher, and the sub-compartments with low-value (cold spots) shifted to the south, where the economy is underdeveloped and with lower population density; (4) From 2007 to 2017, the Gini coefficient of the FEF in the study area decreased, indicating that the regional ecological equity had initially improved. The urbanization and industrialization process of the urban suburbs is a double-edged sword. On the one hand, the process has caused the fragmentation of forest landscape, the decline of the forest area, and the unbalanced spatial distribution of the population. On the other hand, the huge material wealth and human capital accumulated through industrialization have promoted regional ecological equity and improved the living environment of the local residents. [ABSTRACT FROM AUTHOR]

Forest decline is a significant issue affecting critical ecosystem processes worldwide. Here, we describe mortality in Pinus sylvestris L. monitored trees caused by the inhabitation of pine bark beetles (Tomicus minor Hart.) in symbiosis with ophiostomatoid fungi (Ophiostoma piceae (Munch) H. et P. Sydow) infection in the forest-steppe of central Siberia. Stem sap flow (Q) and stem diameter fluctuations (dRc) were monitored in eight pine trees during seven consecutive growing seasons (2015–2021). In addition, microcore sampling every ten days allowed the determination of stem wood formation in monitored trees in the 2021 growing season. During 2020 and 2021, two cases of Q termination were recorded among the monitored trees, with microcores revealing no cambium formation. Thus, the seasonal Q onset matches the beginning of the beetle dispersal period when they attack and inhabit tree stems. The decline of circumferential stem size began 10–12 days after Q onset, during the massive inhabitation of beetles into the stems. The disturbance of Q in trees occurred in 21–23 days, and total cessation of Q was observed 23–26 days after the Q onset at the beetle's egg development phase. The timing of dRc disturbance and Q cessation observed directly coincides with the beetle life cycle. Thus, the phenology of pine trees and T. minor beetles is driven by seasonal weather conditions, particularly the cumulative air temperature (>0 °C). [ABSTRACT FROM AUTHOR]

The article discusses a study by N. Bochow and N. Boers, published in the issue, which designed a novel model of the coupled forest-atmosphere system and used it to search for signs of Amazon dieback. Topics include comparison of global climate model simulations, detection of early signs of Amazon Forest dieback, and avenues for future model improvements.

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]

Future climate forecasts predict major changes that will have negative impacts on the distribution, abundance, and dynamics of forest ecosystems. In Mexico, there is evidence of symptoms of massive forest decline; however, there is no consensus in terms of attributing these symptoms to climate change. This study aimed to provide evidence of forest decline possibly associated with climatic change in the highland pine (Pinus hartwegii Lindl.) populations of the Nevado de Toluca Flora and Fauna Protection Area. Using unmanned aerial vehicles (UAV) equipped with multispectral sensors, the study applied digital photogrammetry techniques, automated tree crown detection algorithms, and calculation of the normalized difference vegetation index (NDVI) and leaf chlorophyll index (LCI) to assess forest health across an altitudinal transect (from 3300 m to the timberline at 4040 m elevation). Climate analysis was conducted with TerraClimate data using mean annual temperature (MAT), April temperature, and Palmer Drought Severity Index (PDSI) from the studied altitudinal transect and its xeric limit. We found that lower altitude populations had significantly higher stress levels, indicating forest decline phenomena, while intermediate altitude populations showed greater vigor of the detected trees. Statistically significant differences in the NDVI and LCI values along the altitudinal gradient provided evidence of forest decline in terms of forest vigor and productivity, with the greatest disturbance found at the lower altitude of the examined forest species. The analysis of the climatic data revealed an increase in April temperature +1.4 °C of the xeric limit of the transect (low altitude) when comparing the reference period, 1961–1990 (mean: 12.17 °C), with the decade prior to our study (2011–2020; mean: 13.57 °C). This would be equivalent to an upward shift in elevation of 280 m of the xeric limit. In addition, the PDSI analysis revealed that droughts are becoming increasingly intense at a rate of 0.06 PDSI units per decade, with greater intensity in the last five years. These findings highlight the negative impacts of climate change on forest ecosystems and the urgent need for alternative forest management and conservation practices to increase resilience and adaptation in the temperate forests of Mexico. This study sets a precedent for further research to improve our understanding of the impacts of climate change on forest ecosystems and the development of sustainable management practices. [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]

(1) Background--Ecological industrialization takes ecological resources as the main research subject and realizes the economic value of ecological products and services by means of socialized production and market-oriented operation. (2) Methods--The weights of each index in the evaluation index system of ecological industrialization development level were determined according to entropy weight method, and the development level of ecological industrialization was measured by entropy weight TOP SIS model. (3) Results--First, the overall development level of ecological industrialization of the state-owned forest areas in Heilongjiang Province was low from 2001 to 2008, and the development index of other system levels was low except for the high development index of ecological environment quality. Due to the implementation of a series of ecological projects, the development index of ecological industrialization from 2009 to 2018 began to improve, and the development index of the four system levels also began to increase. Affected by the system transformation of Yichun Forest Industry Group and the COVID-19 pandemic, the development index of ecological industrialization from 2019 to 2021 began to decline. In addition to the continuous increase in the ecological environment quality level, the development index of the other three system levels declined. Second, the obstacle degree of each system level of ecological industrialization of the state-owned forest areas in Heilongjiang Province showed a trend of fluctuation decline from 2001 to 2018. Except for ecological environment quality level, the obstacle degree of the other system levels increased from 2019 to 2021. There were 17 obstacle factors affecting the development level of ecological industrialization, among which the average obstacle degree of forest resource index, pollution management index, industrial structure index and output value of pillar industry was the highest. (4) Conclusions and Discussions--First, the development level of ecological industrialization of the state-owned forest areas in Heilongjiang Province showed a fluctuating upward trend from 2001 to 2021, and the development level of ecological industrialization was constantly improving. Second, the change trend of the development level of the system level of ecological industrialization was different. The development level of the ecological environment quality continued to rise, while the development level of the other three system levels fluctuated first and then continued to decline. Third, the change of system level obstacle degree affecting the development of ecological industrialization had phases. The obstacle degree of ecological environment quality was the largest from 2001 to 2018, and the pillar industry level became the new main obstacle factor from 2018 to 2021. Fourth, the distribution of indexes restricting the development of ecological industrialization of the state-owned forest areas in Heilongjiang province was uneven in each system level. Forest resources, pollution management, industrial structure and output value of pillar industries were the main obstacle factors. According to the above research conclusions, the following policy recommendations are put forward: First, give priority to protection and improve the quality of the ecological environment. Second, optimize the industrial layout and improve the regional economic level. Third, extend the industrial chain and improve the level of pillar industries. Fourth, expand financing channels and increase capital investment. [ABSTRACT FROM AUTHOR]

Sub-Saharan Africa is well endowed with both renewable and non-renewable natural resources critical in supporting several forms of development on the continent. Key among these is natural forest resources. However, the population explosion in sub-Saharan Africa in general and Uganda, in particular, is threatening the survival of these forests due to the associated increasing demand for food, fodder, energy, and land for settlement. The study was conducted in Yumbe district where the forests considered included woodland and bushland since tropical high forests have been depleted or degraded by human activities. We used a predictive model to map future forest cover loss amidst the rapidly increasing population in Yumbe district in Uganda. Specifically, the study analyzed the relationship between population dynamics and forest cover change to predict future forest cover changes. To analyze changes in forest cover, the study utilized Landsat satellite imagery for 1990, 2000, 2010, and 2021; while the population data for the respective years was obtained from the Uganda Bureau of Statistics (UBOS). To explain the role of anthropogenic forces on forest cover change, the study considered different land use types as explanatory variables: planted forests, subsistence farmland, built-up areas, and other land use types. It then explored the interactions between these variables and forest cover change in the study area. Population-forest cover change model was developed to evaluate three decades of population and trends of forest cover to predict forest cover for 2032. The results indicate that in the three decades, the population increased by more than sixfold, and land area under subsistence agriculture, a proxy of population increased by 195.2%, but the forest cover declined by 80.3%. It is predicted that the forest cover will be lost completely by 2032 when the population reaches an estimated 838,078 from the current 657,430 people. This study, therefore, recommends that off-land employment opportunities such as tourism, apiary, transport, and manufacturing industries should be expanded in order to save forest resources from spatially extensive agricultural land uses. [ABSTRACT FROM AUTHOR]

This study evaluated historical land-cover states in order to identify potential land-use transition regimes leading to land degradation. Landsat satellite datasets were used to characterize land-cover states for 1986–2017 period. The multinomial probability distribution was used to establish sample size for training and accuracy assessment. Using a hybrid image classification approach, individual satellite images were initially clustered using the ISODATA technique, and spectral classes later transformed posteriori into respective thematic classes. Maximum Likelihood Function was subsequently used to assign pixels into classes with highest probability. Approximately 12% of mixed forest declined, while cropland increased by 30% between 1995–2008. [ABSTRACT FROM AUTHOR]

We re-inventoried red wood ant nests (RWA) in 12 study sites (≈1281 ha) in the tectonically active Westeifel Volcanic Field, Germany, in an area-wide and integrated ecosystem approach after 12 years. Combined with the re-identification of previously mapped nests using a photo database, this approach leads to more accurate nest counts in (re)inventories. A total increase in nests from 1144 (2009) to 1252 (2021), and a dramatic one for the Heidberg site by 52-fold (2009) and 85-fold (2021) compared to a 1984 inventory was observed, contrasting with earlier postulations of a decline in RWA. Early to medium mature (41–80 years) and mature (≥81–140 years) spruce forests were the preferred habitat. A large increase in small-sized nests suggests an increase in new nest settlements also in clearings, despite climate-induced forest dieback over the past decade. A decline in biodiversity in the herbaceous layer was observed; highly proliferating blackberries had no negative impact on RWA nests. Monitoring of woodpecker cavities in RWA nests is suggested as an indirect indicator tool for evaluating populations in forests. Positive ground movement rates caused by the Eifel plume are suggested as another factor favoring nest settlements, especially in NE-SW and WNW-ESE directions. This study contributes to the urgent need for updating the statistical data required to (a) effectively substantiate the status quo of RWA occurrences, (b) protect RWA as ecosystem engineers, (c) advance understanding of GeoBio-Interactions in the wake of climate change, and (d) contribute to the German government's Insect Conservation Action Program. [ABSTRACT FROM AUTHOR]

Black locust is the second-most-often planted tree worldwide, particularly for restoration plantations, but drought dieback and growth declines are being reported. Currently, we lack information on these ecosystems' water and carbon fluxes, in relation to climatic variability. Here, we employed eddy covariance to determine the gross primary production (GPP) and evapotranspiration (ET) of a black locust post-mining restoration plantation in NW Greece over c. 2.5 years. Additionally, we applied Generalized Additive Models (GAMs) to study the effects of key environmental drivers (vapour pressure deficit—VPD, soil water content—SWC, solar radiation—Rg and enhanced vegetation index—EVI) on GPP and ET during summer months. Both diurnally and seasonally, GPP increased with increasing Rg, SWC and EVI, but was saturated after certain thresholds (Rg: 400 W m−2, SWC: 25%, EVI: 0.65). In contrast, GPP declined strongly with increasing VPD. Overall, GPP was maintained at a high level, at the cost of ET, which constantly raised with increasing solar radiation and SWC and was not responsive to enhanced VPD, indicating a non-conservative water use. At present, these black locust plantations exhibit favourable productivity and no drought stress, but increasing VPD in the context of climate change may, ultimately, negatively impact these ecosystems. [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]

Drought-induced crown dieback depends on plant nutrient status. This research examined the leaves and roots nutrients of Persian oak trees (Quercus brantii Lindl.) under the effects of drought and tree decline. The leaves and roots of oak trees were sampled randomly on the four main sides of their crown to analyze the N, P, K, Ca, and Mg. In healthy and declining trees, the N, P, and K content in the leaves was higher than in the roots, while the Ca content in the leaves was lower than in roots. The N and P in the roots of healthy trees had decreasing temporal changes, but these elements did not have significant temporal changes in the roots of declining trees. Leaf P showed decreasing temporal changes. The temporal decrease of root N and P and leaf P showed a negative effect of drought on Persian oak trees by reducing their ability to absorb water and nutrients and transfer them to their leaves. The higher concentration of elements in the leaves of oak trees, in addition to showing the decrease in the absorption of elements by the roots from the soil, can indicate a protective mechanism of oak trees against drought stress. [ABSTRACT FROM AUTHOR]

Anthropogenic damage in the U.S. has led to declines in mangrove forest area which have been mitigated in part by mangrove habitat creation; however, these creation projects are rarely monitored annually long-term. This study monitored the succession of vegetation of created mangrove forests in Cockroach Bay Aquatic Preserve (Ruskin, FL) using annual sampling chronosequences (sites aged 3 through 21 years) compared to single-year sampling chronosequences (sites aged 8, 15, and 21 only), with the latter approach often providing poorer resolution of patterns. This study supports others' findings that created mangrove forest development is slow, taking decades. At this study location, Laguncularia racemosa acted as the pioneer species, successionally dominating the young forest as seedlings, juveniles, and young trees. In the oldest site (aged 21 years), classic mangrove zonation still had not yet been established. For this and similar studies, chronosequences are the most realistic option for long-term monitoring due to the labor and cost needed for decades-long assessment; however, this approach depends on the necessary and sometimes false assumption that different sites follow similar successional pathways. We advocate long-term annual sampling using a chronosequence, particularly until different sites are assessed at the same age, to obtain the resolution needed to fully assess created mangrove forest succession. Expanding the use of chronosequence in restoration assessment, a seemingly novel approach given its low representation in the published literature, can significantly enhance assessment outcomes while utilizing existing tools and resources. We further advocate the use of skilled volunteers to help fill labor shortcomings, based upon our own highly successful efforts. [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]