Plenter forests,also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests.They are considered as an adaptation option to mitigate...Plenter forests,also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests.They are considered as an adaptation option to mitigate climate change effects.In this study,we present a conceptual approach to determine the potentially suitable area for plenter forest management within central European mixed species forests and apply our approach to the case study area in Styria,the south-eastern Province of Austria.The concept is based on ecological and technicaleconomic constraints and considers expected future climate conditions and its impact on plenter forest management.For each 1 ha forest pixel,we assess the ecological conditions for plenter forest management according to the autecological growth conditions of silver fir,and at least one additional shade tolerant tree species.The technical-economic constraints are defined by slope(≤30%)and distance to the next forest road(≤100 m)to ensure cost-efficient harvesting.The results show that under current climate conditions 28.1%or 305,349 ha of the forests in Styria are potentially suitable for plenter forest management.For the years 2071–2100 and under the climate change scenario RCP 4.5,the potential area decreases to 286,098 ha(26.3%of the total forest area)and for the scenario RCP 8.5 to 208,421 ha(19.1%of the total forest area).The main reason for these changes is the unfavourable growing conditions for silver fir in the lowlands,while in the higher elevations silver fir is likely to expand.Our results may serve forest managers to identify areas suitable for plenter forests and assist in the transformation of even-aged pure forests to uneven-aged forests to increase resistance,resilience,and biodiversity under climate change.展开更多
In this study,we used an extensive sampling network established in central Romania to develop tree height and crown length models.Our analysis included more than 18,000 tree measurements from five different species.In...In this study,we used an extensive sampling network established in central Romania to develop tree height and crown length models.Our analysis included more than 18,000 tree measurements from five different species.Instead of building univariate models for each response variable,we employed a multivariate approach using seemingly unrelated mixed-effects models.These models incorporated variables related to species mixture,tree and stand size,competition,and stand structure.With the inclusion of additional variables in the multivariate seemingly unrelated mixed-effects models,the accuracy of the height prediction models improved by over 10% for all species,whereas the improvement in the crown length models was considerably smaller.Our findings indicate that trees in mixed stands tend to have shorter heights but longer crowns than those in pure stands.We also observed that trees in homogeneous stand structures have shorter crown lengths than those in heterogeneous stands.By employing a multivariate mixed-effects modelling framework,we were able to perform cross-model random-effect predictions,leading to a significant increase in accuracy when both responses were used to calibrate the model.In contrast,the improvement in accuracy was marginal when only height was used for calibration.We demonstrate how multivariate mixed-effects models can be effectively used to develop multi-response allometric models that can be easily calibrated with a limited number of observations while simultaneously achieving better-aligned projections.展开更多
Nothofagus alessandrii forests in the Mediterranean region of Chile face significant threats from deforestation,fragmentation,wildfires,and climate change.This study investigated the temporal and spatial dynamics of N...Nothofagus alessandrii forests in the Mediterranean region of Chile face significant threats from deforestation,fragmentation,wildfires,and climate change.This study investigated the temporal and spatial dynamics of N.alessandrii populations and their implications for habitat fragmentation and connectivity.Using remote sensing data and geographic information system analysis,we assessed deforestation patterns,fragmentation metrics,and connectivity indices for different scenarios between 2009 and 2022.A reduction in the N.alessandrii forest area,extensive fragmentation,and decreased connectivity were observed over time,with wildfires exacerbating these trends.Reforestation simulations showed the potential of targeted restoration efforts to improve connectivity,especially when focusing on proximate patches.However,careful consideration of seed dispersal distances and wildfire risk is essential for effective reforestation planning.Overall,our findings underscore the urgent need for conservation interventions to preserve N.alessandrii forests and their biodiversity in Chile's coastal mountain ecosystems.A proactive and collaborative approach is essential to ensure the survival of these forests for future generations.展开更多
As the impact of climate change and anthropogenic disturbance continues to intensify around the world,the ecological integrity(EI)of forest ecosystems is compromised in various ways.This study aims to quantify ecologi...As the impact of climate change and anthropogenic disturbance continues to intensify around the world,the ecological integrity(EI)of forest ecosystems is compromised in various ways.This study aims to quantify ecological integrity,explore its latitudinal patterns,and identify the potential determinants behind it.We selected 15 indicators of forest composition,structure,and function and used two approaches to quantify ecological integrity.The results show a significant negative correlation between forest ecological integrity and increasing latitude.Climate emerged as the main driver of the latitudinal pattern compared to anthropogenic and other influencing factors.Our study offers a new approach to quantifying ecological integrity based on a set of indicators that may help assess the contribution of forest ecosystems in conservation,restoration,and ecosystem services.展开更多
Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the de...Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the detection of contemporary trends in both disturbances and community-level responses. Quantifying the attributes of historical disturbances is challenging due to their transient episodic nature, with decades-to centurieslong intervals between recurrences. Unmanaged primary forests that support centuries-old trees therefore serve as unique reference systems for quantifying past disturbance regimes. We surveyed relict stands of primary beech-dominated forests over wide environmental gradients in the Carpathian Mountains of Europe. We collected core samples from 3,026 trees in 208 field survey plots distributed across 13 forest stands in two countries. We used dendrochronological methods to analyze time-series of annually-resolved ring-width variation and to identify anomalous growth patterns diagnostic of past forest canopy removal. A 180-year record(1810–1990) of spatially and temporally explicit disturbance events(n =333) was compiled and used to derive s tatistical attributes of the disturbance regime. We quantified disturbance severity(canopy area lost), patch size, and return intervals. Our analyses describe a complex regime where a background of relatively frequent, smallscale, low-to intermediate-severity disturbance was punctuated by episodic large-scale high-severity events. Even the most severe events were non-catastrophic at a stand level, leaving significant residual tree cover that supported a continuity of ecological function. We did not detect evidence for an expected climate-induced intensification of disturbance with time, but methodological limitations precluded an assessment of disturbance activity in the decades since 1990.展开更多
Warm-wet climatic conditions are widely regarded as conducive to remarkable tree growth,alleviating climatic pressures.However,the notable decline in tree growth observed in the southern edge of boreal forests has hei...Warm-wet climatic conditions are widely regarded as conducive to remarkable tree growth,alleviating climatic pressures.However,the notable decline in tree growth observed in the southern edge of boreal forests has heightened concerns over the spatial-temporal dynamics of forest decline.Currently,attaining a comprehensive grasp of the underlying patterns and their propelling factors remains a formidable challenge.We collected tree ring samples from a network of 50 sites across the Greater Xing'an Mountains.These samples were subsequently grouped into two distinct clusters,designated as Groups A and B.The percentage change of growth(GC,%)and the proportion of declining sites were utilized to assess forest decline.The decline in tree growth within Larix gmelinii forests exhibits significant regional variation,accompanied by temporal fluctuations even within a given region.Group A exhibited a pronounced increase in frequency(59.26%)of occurrences and encountered more severe declines(21.65%)in tree growth subsequent to the 1990s,contrasting sharply with Group B,which observed lower frequencies(20.00%)and relatively less severe declines(21.02%)prior to the 1980s.The primary impetus underlying the opposite radial growth increments observed in Larix gmelinii trees from the interplay between their differential response to temperatures and wetter climatic conditions,which is significantly influenced by varying stand densities.In cold-dry conditions,low-density forests may experience soil water freezing,exacerbating drought conditions and thereby inhibiting tree growth,in Group B.Trees growth in high-density stands is restrained by warm-wet conditions,in Group A.These results provide new insights into the variability at the southern edge of the boreal forest biome with different responses to density and climate.展开更多
Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety o...Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety of soils and at altitudes ranging from sea level to 2200 m,especially in Atlantic and sub-Mediterranean climates,and it is sensitive to low winter temperatures,early and late frosts,as well as high summer temperatures.Sessile oak forms both pure and mixed stands especially with broadleaves such as European beech,European hornbeam,small-leaved lime and Acer spp.These form the understorey of sessile oak stands,promoting the natural shedding of lower branches of the oak and protecting the trunk against epicormic branches.Sessile oak is a long-lived,light-demanding and wind-firm species,owing to its taproot and heart-shaped root system.Its timber,one of the most valuable in Europe,is important for fur-niture-making(both solid wood and veneer),construction,barrels,railway sleepers,and is also used as fuelwood.It is one of the few major tree species in Europe that is regener-ated by seed(naturally or artificially)and by stump shoots in high forest,coppice-with-standards and coppice forests.Sessile oak forests are treated in both regular and irregular systems involving silvicultural techniques such as uniform shelterwood,group shelterwood,irregular shelterwood,irregular high forest,coppice-with-standards and simple coppice.Young naturally regenerated stands are managed by weeding,release cutting and cleaning-respacing,keeping the stands quite dense for good natural pruning.Plantations are based on(1)2-4-year old bare-root or container-grown seedlings produced in nurseries using seeds from genetic resources,seed stands and seed orchards.The density of sessile oak plantations(mostly in rows,but also in clusters)is usually between 4000 and 6000 ind.ha^(−1).Sessile oak silviculture of mature stands includes crown thinning,focus-ing on final crop trees(usually a maximum of 100 ind.ha^(−1))and targeting the production of large-diameter and high quality trees at long rotation ages(mostly over 120 years,sometimes 250-300 years).In different parts of Europe,conversion of simple coppices and coppice-with-standards to high forests is continuing.Even though manage-ment of sessile oak forests is very intensive and expensive,requiring active human intervention,the importance of this species in future European forests will increase in the con-text of climate change due to its high resistance to distur-bance,superior drought tolerance and heat stress resistance.展开更多
Disturbances such as forest fires,intense winds,and insect damage exert strong impacts on forest ecosystems by shaping their structure and growth dynamics,with contributions from climate change.Consequently,there is a...Disturbances such as forest fires,intense winds,and insect damage exert strong impacts on forest ecosystems by shaping their structure and growth dynamics,with contributions from climate change.Consequently,there is a need for reliable and operational methods to monitor and map these disturbances for the development of suitable management strategies.While susceptibility assessment using machine learning methods has increased,most studies have focused on a single disturbance.Moreover,there has been limited exploration of the use of“Automated Machine Learning(AutoML)”in the literature.In this study,susceptibility assessment for multiple forest disturbances(fires,insect damage,and wind damage)was conducted using the PyCaret AutoML framework in the Izmir Regional Forest Directorate(RFD)in Turkey.The AutoML framework compared 14 machine learning algorithms and ranked the best models based on AUC(area under the curve)values.The extra tree classifier(ET)algorithm was selected for modeling the susceptibility of each disturbance due to its good performance(AUC values>0.98).The study evaluated susceptibilities for both individual and multiple disturbances,creating a total of four susceptibility maps using fifteen driving factors in the assessment.According to the results,82.5%of forested areas in the Izmir RFD are susceptible to multiple disturbances at high and very high levels.Additionally,a potential forest disturbances map was created,revealing that 15.6%of forested areas in the Izmir RFD may experience no damage from the disturbances considered,while 54.2%could face damage from all three disturbances.The SHAP(Shapley Additive exPlanations)methodology was applied to evaluate the importance of features on prediction and the nonlinear relationship between explanatory features and susceptibility to disturbance.展开更多
Unoccupied aircraft systems (UAS) are increasingly used to create spatial databases for use in natural resource research and in other disciplines. We describe our experience with the recovery of an UAS platform that b...Unoccupied aircraft systems (UAS) are increasingly used to create spatial databases for use in natural resource research and in other disciplines. We describe our experience with the recovery of an UAS platform that became lodged in a tree located next to a small river island after experiencing communication loss. The UAS platform was a DJI M200 series aircraft that we had used for remote sensing applications over several years without issue. During remote sensing of a riparian restoration project, the M200 descended vertically downward after communication loss, became lodged in a tree crown, and was suspended above the river. A tree climber was temporarily able to grasp the platform but a landing support released and the platform fell into the river. Although being submerged for less than 30 seconds, inspection of the internal chassis later revealed at least some moisture had infiltrated into the chassis likely impacting electrical components. The sensor escaped without noticeable damage and operated without apparent impact after being subjected to prolonged drying. We were unable to determine the specific reason for communication loss after examining digital flight logs but investigated other similar reported loss occurrences to better understand what may have transpired. We provide some recommendations for minimizing loss based on our analysis of reported incidents with similar UAS platforms and from our experiences in using UAS for remote sensing in forested environments.展开更多
The efficient hydrogenolysis of esters to alkanes is the key protocol for producing advanced biofuels from renewable plant oils or fats.Due to the low reactivity of the carbonyl group in esters,a high reaction tempera...The efficient hydrogenolysis of esters to alkanes is the key protocol for producing advanced biofuels from renewable plant oils or fats.Due to the low reactivity of the carbonyl group in esters,a high reaction temperature(>250℃)is the prerequisite to ensure high conversion of esters.Here,we report a highly dispersed MoO_(x)-Ru/C bimetallic catalyst for the efficient hydrogenolysis of esters to alkanes under 150°C.The optimal catalyst exhibits>99%conversion of methyl stearate and 99%selectivity to diesel-range alkanes,reaching a high rate of up to 2.0 mmol gcat^(–1)h^(–1),5 times higher than that of Ru/C catalyst(MoO_(x)/C is inert).Integrated experimental and theoretical investigations attribute the high performance to the abundant MoO_(x)-Ru interfacial sites on the catalyst surface,which offers high activity for the C–O cleavage of esters.Furthermore,the dispersed MoO_(x)species significantly weaken the hydrocracking activity of the metallic Ru for C–C bonds,thus yielding alkane products without carbon loss.This study provides a facile and novel strategy for the design of high-performance heterogeneous catalysts for the hydrodeoxygenation of biomass-derived esters to alkane products.展开更多
Growing climate change concerns have intensified the focus on agribusiness sustainability,driving an urgent energy transition to improve production efficiency and mitigate environmental harm.The complex interplay betw...Growing climate change concerns have intensified the focus on agribusiness sustainability,driving an urgent energy transition to improve production efficiency and mitigate environmental harm.The complex interplay between energy efficiency and energy consumption highlights the essential role of strategic energy policies in ensuring sustainable development.This study used the Double-Log regression model with bootstrap resampling to examine the rebound effect in the energy transition of agribusiness focusing on five Latin American countries including Brazil,Argentina,Uruguay,Colombia,and Mexico based on the agricultural sector data during 2010–2022.The findings revealed that the rebound effect significantly influences energy transition,with varying degrees of impact across agricultural sectors.This study identified partial rebound effect across all five countries,with elasticity coefficient varying from 9.63%(Colombia’s coffee sector)to 89.12%(Brazil’s livestock sector).In Brazil’s sugarcane sector,nonrenewable energy,agricultural employment,and irrigation efficiency were identified as key factors influencing energy consumption,while in livestock sector,energy consumption was affected by CH_(4)emissions,income and well-being of farmers,water consumption,and water conservation practices.In Mexico’s livestock sector,CH_(4)emissions,nonrenewable energy,and water conservation practices were the key factors affecting energy consumption.In Argentina’s sugarcane sector,pesticides,NO_(2)emissions,renewable energy,and agricultural employment were the key factors affecting energy consumption,while renewable energy,income and well-being of farmers,and water consumption were the key factors affecting energy consumption in livestock sector.In Uruguay’s livestock sector,non-renewable energy,income and well-being of farmers,and irrigation efficiency were the key factors affecting energy consumption.In Colombia’coffee sector,NO_(2)emissions and irrigation efficiency were identified as key factors influencing energy consumption.Finally,this study reinforces the importance of aligning energy transition with Sustainable Development Goals(SDGs),ensuring that energy efficiency gains do not inadvertently increase energy consumption or environmental degradation.展开更多
We demonstrate a multi-method approach towards discovering and structuring sustainability transition knowl edge in marginalized mountain regions.By employing reflective thinking,artificial intelligence(AI)-powered tex...We demonstrate a multi-method approach towards discovering and structuring sustainability transition knowl edge in marginalized mountain regions.By employing reflective thinking,artificial intelligence(AI)-powered text summarization and text mining,we synthesize experts’narratives on sustainable development challenges and solutions in Kardüz Upland,Türkiye.We then analyze their alignment with the UN Sustainable Development Goals(SDGs)using document embedding.Investment in infrastructure,education,and resilient socio-ecological systems emerged as priority sectors to combat poor infrastructure,geographic isolation,climate change,poverty,depopulation,unemployment,low education levels,and inadequate social services.The narratives were closest in substance to SDG 1,3,and 11.Social dimensions of sustainability were more pronounced than environmental dimensions.The presented approach supports policymakers in organizing loosely structured sustainability tran sition knowledge and fragmented data corpora,while also advancing AI applications for designing and planning sustainable development policies at the regional level.展开更多
The study of the oxygen evolution reaction(OER)mechanism is vital for advancing our understanding of this pivotal energy conversion process.This review synthesizes recent advancements in OER mechanism,emphasizing the ...The study of the oxygen evolution reaction(OER)mechanism is vital for advancing our understanding of this pivotal energy conversion process.This review synthesizes recent advancements in OER mechanism,emphasizing the intricate relationship between catalytic mechanisms and catalyst design.This review discusses the connotation and cutting-edge progress of traditional mechanisms such as adsorbate evolution mechanism(AEM)and lattice oxygen mechanism(LOM)as well as emerging pathways including oxide path mechanism(OPM),oxo-oxo coupling mechanism(OCM),and intramolecular oxygen coupling mechanism(IMOC)etc.Innovative research progress on the coexistence and transformation of multiple mechanisms is highlighted,and the intrinsic factors that influence these dynamic processes are summarized.Advanced characterization techniques and theoretical modeling are underscored as indispensable tools for revealing these complex interactions.This review provides guiding principles for mechanism-based catalyst design.Finally,in view of the multidimensional challenges currently faced by OER mechanisms,prospects for future research are given to bridge the gap between mechanism innovation and experimental verification and application.This comprehensive review provides valuable perspectives for advancing clean energy technologies and achieving sustainable development.展开更多
The author affiliation and the funding information in the Acknowledgement section of the online version of the original article was revised.One affiliation(the 8th affiliation)of the first author is added.The Acknowle...The author affiliation and the funding information in the Acknowledgement section of the online version of the original article was revised.One affiliation(the 8th affiliation)of the first author is added.The Acknowledgement section of the original article has been revised to:Acknowledgments:This research was funded by the National University of Mongolia under grant agreement P2023(grant number P2023-4578)and supported by the Chey Institute for Advanced Studies“International Scholarship Exchange Fellowship for the academic year of 2024-2025”,Republic of Korea,and the National University of Mongolia.We would like to acknowledge the National University of Mongolia and Soumik Das from the Center for the Study of Regional Development,Jawaharlal Nehru University,New Delhi-110067,for his valuable assistance in preparing the geological maps.展开更多
Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium ...Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium dioxide(M-TiO_(2))/water(H_2O)was developed,and its confinement effect was regulated by changing the pore structure of M-TiO_(2).CO_(2) solubility in the hybrid sorbent was measured experimentally,and the thermodynamic properties including Henry's constant and desorption enthalpy were calculated.Furthermore,the confinement effect in the hybrid sorbent was quantified.Additionally,the hybrid sorbent was recycled with a multi-cycle experiment.The results showed that M-TiO_(2) calcined at 773.2 K(MT500)could lead to an efficient confinement effect.CO_(2) solubility in the hybrid sorbent increased by 49.8%compared to that of H_2O when the mass fraction of[Hmim][NTf_2]/MT500 was 5.0%(mass),where the contribution of confinement effect on Gibbs free energy occupied 5.2%.展开更多
CO_(2) conversion to CO via the reverse water-gas shift(RWGS)reaction is limited by a low CO_(2) conversion rate and CO selectivity.Herein,an efficient RWGS catalyst is constructed through Enteromorpha prolifera–deri...CO_(2) conversion to CO via the reverse water-gas shift(RWGS)reaction is limited by a low CO_(2) conversion rate and CO selectivity.Herein,an efficient RWGS catalyst is constructed through Enteromorpha prolifera–derived N-rich mesoporous biochar(EPBC)supported atomic-level Cu-Mo_(2)C clusters(Cu-Mo_(2)C/EPBC).Unlike traditional acti-vated carbon(AC)supported Cu-Mo_(2)C particles(Cu-Mo_(2)C/AC),the Cu-Mo_(2)C/EPBC not only presents the better graphitization degree and larger specific surface area,but also uniformly andfirmly anchors atomic-level Cu-Mo_(2)C clusters due to the existence of pyridine nitrogen.Furthermore,the pyridine N of Cu-Mo_(2)C/EPBC strengthens an unblocked electron transfer between Mo_(2)C and Cu clusters,as verified by X-ray absorption spectroscopy.As a result,the synergistic effect between pyridinic N anchoring and the clusters interaction in Cu-Mo_(2)C/EPBC facilitates an improved CO selectivity of 99.95%at 500℃ compared with traditional Cu-Mo_(2)C/AC(99.60%),as well as about 3-fold CO_(2) conversion rate.Density functional theory calculations confirm that pyr-idine N-modified carbon activates the local electronic redistribution at Cu-Mo_(2)C clusters,which contributes to the decreased energy barrier of the transition state of CO^(*)+O^(*)+2H^(*),thereby triggering the transformation of rate-limited step during the redox pathway.This biomass-derived strategy opens perspective on producing sustain-able fuels and building blocks through the RWGS reaction.展开更多
Background: There is a serious lack of experience regarding the productive potential of the natural forests in northeastern China, which severely limits the development of sustainable forest management strategies for ...Background: There is a serious lack of experience regarding the productive potential of the natural forests in northeastern China, which severely limits the development of sustainable forest management strategies for this most important forest region in China. Accordingly, the objective of this study is to develop a first comprehensive system for estimating the wood production for the five dominant forest types.Methods: Based on a network of 384 field plots and using the state-space approach, we develop a system of dynamic stand models, for each of the five main forest types. Four models were developed and evaluated, including a base model and three extended models which include the effects of dominant height and climate variables. The four models were fitted, and their predictive strengths were tested, using the "seemingly unrelated regression"(SUR) technique.Results: All three of the extended models increased the accuracy of the predictions at varying degrees for the five major natural forest types of northeastern China. The inclusion of dominant height and two climate factors(precipitation and temperature) in the base model resulted in the best performance for all the forest types. On average, the root mean square values were reduced by 13.0% when compared with the base model.Conclusion: Both dominant height and climate factors were important variables in estimating forest production. This study not only presents a new method for estimating forest production for a large region, but also explains regional differences in the effect of site productivity and climate.展开更多
Wild forest fires are one of the greatest environmental disasters affecting forest resources. Along the coastal zone of the Mediterranean region in Turkey, forested areas are classified as first-degree, fire-sensitive...Wild forest fires are one of the greatest environmental disasters affecting forest resources. Along the coastal zone of the Mediterranean region in Turkey, forested areas are classified as first-degree, fire-sensitive areas. Every year, thousands of hectares of forests have been destroyed in Turkey. In this study, fire-access zones were determined in the Mediterranean forests of Turkey, by utilizing geographic information systems （GIS） technology. The effective reach distance of fire hoses from both sides of roads was considered in order to delineate fireaccess zones. The effective reach distance can vary based on the technical capabilities and hydraulic capacity of fire trucks （minimum and maximum pressures on water pump）; terrain structures （uphill, downhill and flat）; and ground slope. These factors and their influences were studied in fire sensitive forest areas located in the eastern Mediterranean city of Kahramanmaras in Turkey. First, terrain structures on both sides of the road network and groundslope classes were determined based on GIS data layers. Then, fire access zones were delineated according to water pressure data, terrain structures, and ground-slope classes. The results indicated that 69.30 % of the forested areas were within the fire-access zones, while the rest of the forest was out of reach the fire hoses. The accessible areas were also calculated for forested areas with different fire- sensitivity degrees. The accessible areas were 69.59, 69.96, and 67.16 % for the forested areas that are sensitive to fires at the first, second, and third degrees, respectively. This finding has implications for the monitoring and management of fire threats in areas outside of the reach distance. The outside areas should receive extra attention and monitoring during the fire season so that fires are detected ahead of time and management has sufficient time to react. Besides, new roads should be considered for these areas in order to access more lands in a shorter amount of time.展开更多
Forest ecosystems play a crucial role in mitigating global climate change by forming massive carbon sinks. Their carbon stocks and stock changes need to be quantified for carbon budget balancing and international repo...Forest ecosystems play a crucial role in mitigating global climate change by forming massive carbon sinks. Their carbon stocks and stock changes need to be quantified for carbon budget balancing and international reporting schemes. However, direct sampling and biomass weighing may not always be possible for quantification studies conducted in large forests. In these cases, indirect methods that use forest inventory information combined with remote sensing data can be beneficial. Synthetic aperture radar (SAR) images offer numerous opportunities to researchers as freely distributed remote sensing data. This study aims to estimate the amount of total carbon stock (TCS) in forested lands of the Kizildag Forest Enterprise. To this end, the actual storage capacities of five carbon pools, i.e. above- and below-ground, deadwood, litter, and soil, were calculated using the indirect method based on ground measurements of 264 forest inventory plots. They were then associated with the backscattered values from Sentinel-1 and ALOS-2 PALSAR-2 data in a Geographical Information System (GIS). Finally, TCS was separately modelled and mapped. The best regression model was developed using the HH polarization of ALOS-2 PALSAR-2 with an adjusted R^(2) of 0.78 (p < 0.05). According to the model, the estimated TCS was about 2 Mt for the entire forest, with an average carbon storage of 133 t ha^(−1). The map showed that the distribution of TCS was heterogenic across the study area. Carbon hotspots were mostly composed of pure stands of Anatolian black pine and mixed, over-mature stands of Lebanese cedar and Taurus fir. It was concluded that the total carbon stocks of forest ecosystems could be estimated using appropriate SAR images at acceptable accuracy levels for forestry purposes. The use of additional ancillary data may provide more delicate and reliable estimations in the future. Given the implications of this study, the spatiotemporal dynamics of carbon can be effectively controlled by forest management when coupled with easily accessible space-borne radar data.展开更多
Although the scientific knowledge about some associations between physical parameters of the soil is consolidated,studies focused on investigating the dynamics of forest restoration processes and the structure of soil...Although the scientific knowledge about some associations between physical parameters of the soil is consolidated,studies focused on investigating the dynamics of forest restoration processes and the structure of soils remain incipient.The study area is located in Cerrado and is called as Private Natural Heritage Reserve(RPPN)Águas Perenes Forest(perennial water forest)and was selected as a“High Conservation Value Forest”,provides scope to investigate the soil physical properties recovery on passive restoration sites,with different ages but with the same land use history.So,the aim was to investigate the soil density,moisture,penetration resistance and infiltration rate with long-term from old(FA,46 year-old),medium(FB,11 year-old)and young(FC,8 year-old)passive restoration sites.It was observed differences in soil density,as well as in soil moisture,resistance to penetration and infiltration rate.Mean densities recorded for FA,FB and FC were 1.38,1.48 and 1.53 g cm^(-3),respectively.FA recorded higher mean soil moisture(14.9%)than FB(11.5%)and FC(10.0%),whereas mean soil resistance to penetration was increased from FA(0.87 MPa)to FB(0.91 MPa)and FC(1.10 MPa).The average infiltration rate was almost similar in FA and FB(FA=76.43 mm h^(-1);FB=77.48 mm h^(-1))and approximately 39%higher than FC(55.79 mm h^(-1)).Thus,although soil density and moisture were different in each passive restoration site,11 year-old passive restoration site showed similar resistance to penetration and infiltration rate to the old(46 years)passive restoration site.These features allowed seeing improvements in hydrological maintenance in the soil and revealed that passive restoration in Cerrado is able to improve the physical features on a soil presenting similar texture,climate and management history.展开更多
基金part of the project“Areas of Forest Innovation Climate Smart Forestry”(project nr.101726),WP Modelling Plenter Forest vs.Even-aged Forest,funded by the Austrian Ministry of Agriculture,Forestry,Regions and Water Managementfunded by the province of Styria(Austria),the Austrian Federal Ministry of Agriculture,Forestry,Regions and Water Management and the European Union via the projects“Waldtypisierung Steiermark-FORSITE”(LE14-20)and“FORSITEⅡ-Investigation of the ecological base line information for a dynamic forest site classification in Upper Austria,Lower Austria and Burgenland”(101746)financial support came from BOKU University。
文摘Plenter forests,also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests.They are considered as an adaptation option to mitigate climate change effects.In this study,we present a conceptual approach to determine the potentially suitable area for plenter forest management within central European mixed species forests and apply our approach to the case study area in Styria,the south-eastern Province of Austria.The concept is based on ecological and technicaleconomic constraints and considers expected future climate conditions and its impact on plenter forest management.For each 1 ha forest pixel,we assess the ecological conditions for plenter forest management according to the autecological growth conditions of silver fir,and at least one additional shade tolerant tree species.The technical-economic constraints are defined by slope(≤30%)and distance to the next forest road(≤100 m)to ensure cost-efficient harvesting.The results show that under current climate conditions 28.1%or 305,349 ha of the forests in Styria are potentially suitable for plenter forest management.For the years 2071–2100 and under the climate change scenario RCP 4.5,the potential area decreases to 286,098 ha(26.3%of the total forest area)and for the scenario RCP 8.5 to 208,421 ha(19.1%of the total forest area).The main reason for these changes is the unfavourable growing conditions for silver fir in the lowlands,while in the higher elevations silver fir is likely to expand.Our results may serve forest managers to identify areas suitable for plenter forests and assist in the transformation of even-aged pure forests to uneven-aged forests to increase resistance,resilience,and biodiversity under climate change.
基金supported by the European Union and the Romanian Government through the Competitiveness Operational Programme 2014–2020, under the project“Increasing the economic competitiveness of the forestry sector and the quality of life through knowledge transfer,technology and CDI skills”(CRESFORLIFE),ID P 40 380/105506, subsidiary contract no. 17/2020partially by the FORCLIMSOC Nucleu Programme (Contract 12N/2023)+2 种基金project PN 23090101CresPerfInst project (Contract 34PFE/December 30, 2021)“Increasing the institutional capacity and performance of INCDS ‘Marin Drǎcea’in RDI activities-CresPer”LM was financially supported by the Research Council of Finland's flagship ecosystem for Forest-Human-Machine Interplay–Building Resilience, Redefining Value Networks and Enabling Meaningful Experiences (UNITE)(decision number 357909)
文摘In this study,we used an extensive sampling network established in central Romania to develop tree height and crown length models.Our analysis included more than 18,000 tree measurements from five different species.Instead of building univariate models for each response variable,we employed a multivariate approach using seemingly unrelated mixed-effects models.These models incorporated variables related to species mixture,tree and stand size,competition,and stand structure.With the inclusion of additional variables in the multivariate seemingly unrelated mixed-effects models,the accuracy of the height prediction models improved by over 10% for all species,whereas the improvement in the crown length models was considerably smaller.Our findings indicate that trees in mixed stands tend to have shorter heights but longer crowns than those in pure stands.We also observed that trees in homogeneous stand structures have shorter crown lengths than those in heterogeneous stands.By employing a multivariate mixed-effects modelling framework,we were able to perform cross-model random-effect predictions,leading to a significant increase in accuracy when both responses were used to calibrate the model.In contrast,the improvement in accuracy was marginal when only height was used for calibration.We demonstrate how multivariate mixed-effects models can be effectively used to develop multi-response allometric models that can be easily calibrated with a limited number of observations while simultaneously achieving better-aligned projections.
基金funded by Universidad Cato lica del MauleProyectos de Investigacio n con Financiamiento Interno 2022 línea Fortalecimiento Fondecyt Regular。
文摘Nothofagus alessandrii forests in the Mediterranean region of Chile face significant threats from deforestation,fragmentation,wildfires,and climate change.This study investigated the temporal and spatial dynamics of N.alessandrii populations and their implications for habitat fragmentation and connectivity.Using remote sensing data and geographic information system analysis,we assessed deforestation patterns,fragmentation metrics,and connectivity indices for different scenarios between 2009 and 2022.A reduction in the N.alessandrii forest area,extensive fragmentation,and decreased connectivity were observed over time,with wildfires exacerbating these trends.Reforestation simulations showed the potential of targeted restoration efforts to improve connectivity,especially when focusing on proximate patches.However,careful consideration of seed dispersal distances and wildfire risk is essential for effective reforestation planning.Overall,our findings underscore the urgent need for conservation interventions to preserve N.alessandrii forests and their biodiversity in Chile's coastal mountain ecosystems.A proactive and collaborative approach is essential to ensure the survival of these forests for future generations.
基金funded by the National Key R&D Program of China(No.2023YFF1304001-01)the Program of National Natural Science Foundation of China(No.32371870)。
文摘As the impact of climate change and anthropogenic disturbance continues to intensify around the world,the ecological integrity(EI)of forest ecosystems is compromised in various ways.This study aims to quantify ecological integrity,explore its latitudinal patterns,and identify the potential determinants behind it.We selected 15 indicators of forest composition,structure,and function and used two approaches to quantify ecological integrity.The results show a significant negative correlation between forest ecological integrity and increasing latitude.Climate emerged as the main driver of the latitudinal pattern compared to anthropogenic and other influencing factors.Our study offers a new approach to quantifying ecological integrity based on a set of indicators that may help assess the contribution of forest ecosystems in conservation,restoration,and ecosystem services.
基金supported by the Czech Science Foundation project GACR21-27454STechnology Agency of the Czech Republic(project Center for Landscape and Biodiversity,SS02030018).
文摘Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the detection of contemporary trends in both disturbances and community-level responses. Quantifying the attributes of historical disturbances is challenging due to their transient episodic nature, with decades-to centurieslong intervals between recurrences. Unmanaged primary forests that support centuries-old trees therefore serve as unique reference systems for quantifying past disturbance regimes. We surveyed relict stands of primary beech-dominated forests over wide environmental gradients in the Carpathian Mountains of Europe. We collected core samples from 3,026 trees in 208 field survey plots distributed across 13 forest stands in two countries. We used dendrochronological methods to analyze time-series of annually-resolved ring-width variation and to identify anomalous growth patterns diagnostic of past forest canopy removal. A 180-year record(1810–1990) of spatially and temporally explicit disturbance events(n =333) was compiled and used to derive s tatistical attributes of the disturbance regime. We quantified disturbance severity(canopy area lost), patch size, and return intervals. Our analyses describe a complex regime where a background of relatively frequent, smallscale, low-to intermediate-severity disturbance was punctuated by episodic large-scale high-severity events. Even the most severe events were non-catastrophic at a stand level, leaving significant residual tree cover that supported a continuity of ecological function. We did not detect evidence for an expected climate-induced intensification of disturbance with time, but methodological limitations precluded an assessment of disturbance activity in the decades since 1990.
基金National Nature Science Foundation of China(No.32371871)。
文摘Warm-wet climatic conditions are widely regarded as conducive to remarkable tree growth,alleviating climatic pressures.However,the notable decline in tree growth observed in the southern edge of boreal forests has heightened concerns over the spatial-temporal dynamics of forest decline.Currently,attaining a comprehensive grasp of the underlying patterns and their propelling factors remains a formidable challenge.We collected tree ring samples from a network of 50 sites across the Greater Xing'an Mountains.These samples were subsequently grouped into two distinct clusters,designated as Groups A and B.The percentage change of growth(GC,%)and the proportion of declining sites were utilized to assess forest decline.The decline in tree growth within Larix gmelinii forests exhibits significant regional variation,accompanied by temporal fluctuations even within a given region.Group A exhibited a pronounced increase in frequency(59.26%)of occurrences and encountered more severe declines(21.65%)in tree growth subsequent to the 1990s,contrasting sharply with Group B,which observed lower frequencies(20.00%)and relatively less severe declines(21.02%)prior to the 1980s.The primary impetus underlying the opposite radial growth increments observed in Larix gmelinii trees from the interplay between their differential response to temperatures and wetter climatic conditions,which is significantly influenced by varying stand densities.In cold-dry conditions,low-density forests may experience soil water freezing,exacerbating drought conditions and thereby inhibiting tree growth,in Group B.Trees growth in high-density stands is restrained by warm-wet conditions,in Group A.These results provide new insights into the variability at the southern edge of the boreal forest biome with different responses to density and climate.
文摘Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety of soils and at altitudes ranging from sea level to 2200 m,especially in Atlantic and sub-Mediterranean climates,and it is sensitive to low winter temperatures,early and late frosts,as well as high summer temperatures.Sessile oak forms both pure and mixed stands especially with broadleaves such as European beech,European hornbeam,small-leaved lime and Acer spp.These form the understorey of sessile oak stands,promoting the natural shedding of lower branches of the oak and protecting the trunk against epicormic branches.Sessile oak is a long-lived,light-demanding and wind-firm species,owing to its taproot and heart-shaped root system.Its timber,one of the most valuable in Europe,is important for fur-niture-making(both solid wood and veneer),construction,barrels,railway sleepers,and is also used as fuelwood.It is one of the few major tree species in Europe that is regener-ated by seed(naturally or artificially)and by stump shoots in high forest,coppice-with-standards and coppice forests.Sessile oak forests are treated in both regular and irregular systems involving silvicultural techniques such as uniform shelterwood,group shelterwood,irregular shelterwood,irregular high forest,coppice-with-standards and simple coppice.Young naturally regenerated stands are managed by weeding,release cutting and cleaning-respacing,keeping the stands quite dense for good natural pruning.Plantations are based on(1)2-4-year old bare-root or container-grown seedlings produced in nurseries using seeds from genetic resources,seed stands and seed orchards.The density of sessile oak plantations(mostly in rows,but also in clusters)is usually between 4000 and 6000 ind.ha^(−1).Sessile oak silviculture of mature stands includes crown thinning,focus-ing on final crop trees(usually a maximum of 100 ind.ha^(−1))and targeting the production of large-diameter and high quality trees at long rotation ages(mostly over 120 years,sometimes 250-300 years).In different parts of Europe,conversion of simple coppices and coppice-with-standards to high forests is continuing.Even though manage-ment of sessile oak forests is very intensive and expensive,requiring active human intervention,the importance of this species in future European forests will increase in the con-text of climate change due to its high resistance to distur-bance,superior drought tolerance and heat stress resistance.
文摘Disturbances such as forest fires,intense winds,and insect damage exert strong impacts on forest ecosystems by shaping their structure and growth dynamics,with contributions from climate change.Consequently,there is a need for reliable and operational methods to monitor and map these disturbances for the development of suitable management strategies.While susceptibility assessment using machine learning methods has increased,most studies have focused on a single disturbance.Moreover,there has been limited exploration of the use of“Automated Machine Learning(AutoML)”in the literature.In this study,susceptibility assessment for multiple forest disturbances(fires,insect damage,and wind damage)was conducted using the PyCaret AutoML framework in the Izmir Regional Forest Directorate(RFD)in Turkey.The AutoML framework compared 14 machine learning algorithms and ranked the best models based on AUC(area under the curve)values.The extra tree classifier(ET)algorithm was selected for modeling the susceptibility of each disturbance due to its good performance(AUC values>0.98).The study evaluated susceptibilities for both individual and multiple disturbances,creating a total of four susceptibility maps using fifteen driving factors in the assessment.According to the results,82.5%of forested areas in the Izmir RFD are susceptible to multiple disturbances at high and very high levels.Additionally,a potential forest disturbances map was created,revealing that 15.6%of forested areas in the Izmir RFD may experience no damage from the disturbances considered,while 54.2%could face damage from all three disturbances.The SHAP(Shapley Additive exPlanations)methodology was applied to evaluate the importance of features on prediction and the nonlinear relationship between explanatory features and susceptibility to disturbance.
文摘Unoccupied aircraft systems (UAS) are increasingly used to create spatial databases for use in natural resource research and in other disciplines. We describe our experience with the recovery of an UAS platform that became lodged in a tree located next to a small river island after experiencing communication loss. The UAS platform was a DJI M200 series aircraft that we had used for remote sensing applications over several years without issue. During remote sensing of a riparian restoration project, the M200 descended vertically downward after communication loss, became lodged in a tree crown, and was suspended above the river. A tree climber was temporarily able to grasp the platform but a landing support released and the platform fell into the river. Although being submerged for less than 30 seconds, inspection of the internal chassis later revealed at least some moisture had infiltrated into the chassis likely impacting electrical components. The sensor escaped without noticeable damage and operated without apparent impact after being subjected to prolonged drying. We were unable to determine the specific reason for communication loss after examining digital flight logs but investigated other similar reported loss occurrences to better understand what may have transpired. We provide some recommendations for minimizing loss based on our analysis of reported incidents with similar UAS platforms and from our experiences in using UAS for remote sensing in forested environments.
文摘The efficient hydrogenolysis of esters to alkanes is the key protocol for producing advanced biofuels from renewable plant oils or fats.Due to the low reactivity of the carbonyl group in esters,a high reaction temperature(>250℃)is the prerequisite to ensure high conversion of esters.Here,we report a highly dispersed MoO_(x)-Ru/C bimetallic catalyst for the efficient hydrogenolysis of esters to alkanes under 150°C.The optimal catalyst exhibits>99%conversion of methyl stearate and 99%selectivity to diesel-range alkanes,reaching a high rate of up to 2.0 mmol gcat^(–1)h^(–1),5 times higher than that of Ru/C catalyst(MoO_(x)/C is inert).Integrated experimental and theoretical investigations attribute the high performance to the abundant MoO_(x)-Ru interfacial sites on the catalyst surface,which offers high activity for the C–O cleavage of esters.Furthermore,the dispersed MoO_(x)species significantly weaken the hydrocracking activity of the metallic Ru for C–C bonds,thus yielding alkane products without carbon loss.This study provides a facile and novel strategy for the design of high-performance heterogeneous catalysts for the hydrodeoxygenation of biomass-derived esters to alkane products.
文摘Growing climate change concerns have intensified the focus on agribusiness sustainability,driving an urgent energy transition to improve production efficiency and mitigate environmental harm.The complex interplay between energy efficiency and energy consumption highlights the essential role of strategic energy policies in ensuring sustainable development.This study used the Double-Log regression model with bootstrap resampling to examine the rebound effect in the energy transition of agribusiness focusing on five Latin American countries including Brazil,Argentina,Uruguay,Colombia,and Mexico based on the agricultural sector data during 2010–2022.The findings revealed that the rebound effect significantly influences energy transition,with varying degrees of impact across agricultural sectors.This study identified partial rebound effect across all five countries,with elasticity coefficient varying from 9.63%(Colombia’s coffee sector)to 89.12%(Brazil’s livestock sector).In Brazil’s sugarcane sector,nonrenewable energy,agricultural employment,and irrigation efficiency were identified as key factors influencing energy consumption,while in livestock sector,energy consumption was affected by CH_(4)emissions,income and well-being of farmers,water consumption,and water conservation practices.In Mexico’s livestock sector,CH_(4)emissions,nonrenewable energy,and water conservation practices were the key factors affecting energy consumption.In Argentina’s sugarcane sector,pesticides,NO_(2)emissions,renewable energy,and agricultural employment were the key factors affecting energy consumption,while renewable energy,income and well-being of farmers,and water consumption were the key factors affecting energy consumption in livestock sector.In Uruguay’s livestock sector,non-renewable energy,income and well-being of farmers,and irrigation efficiency were the key factors affecting energy consumption.In Colombia’coffee sector,NO_(2)emissions and irrigation efficiency were identified as key factors influencing energy consumption.Finally,this study reinforces the importance of aligning energy transition with Sustainable Development Goals(SDGs),ensuring that energy efficiency gains do not inadvertently increase energy consumption or environmental degradation.
基金work conducted under COST Action CA21125-a European forum for revitalisation of marginalised moun-tain areas(MARGISTAR)supported by COST(European Cooperation in Science and Technology)gratefully acknowledges the support received for the research from the University of Ljubljana’s research program Forest,forestry and renewable forest resources(P4-0059).
文摘We demonstrate a multi-method approach towards discovering and structuring sustainability transition knowl edge in marginalized mountain regions.By employing reflective thinking,artificial intelligence(AI)-powered text summarization and text mining,we synthesize experts’narratives on sustainable development challenges and solutions in Kardüz Upland,Türkiye.We then analyze their alignment with the UN Sustainable Development Goals(SDGs)using document embedding.Investment in infrastructure,education,and resilient socio-ecological systems emerged as priority sectors to combat poor infrastructure,geographic isolation,climate change,poverty,depopulation,unemployment,low education levels,and inadequate social services.The narratives were closest in substance to SDG 1,3,and 11.Social dimensions of sustainability were more pronounced than environmental dimensions.The presented approach supports policymakers in organizing loosely structured sustainability tran sition knowledge and fragmented data corpora,while also advancing AI applications for designing and planning sustainable development policies at the regional level.
文摘The study of the oxygen evolution reaction(OER)mechanism is vital for advancing our understanding of this pivotal energy conversion process.This review synthesizes recent advancements in OER mechanism,emphasizing the intricate relationship between catalytic mechanisms and catalyst design.This review discusses the connotation and cutting-edge progress of traditional mechanisms such as adsorbate evolution mechanism(AEM)and lattice oxygen mechanism(LOM)as well as emerging pathways including oxide path mechanism(OPM),oxo-oxo coupling mechanism(OCM),and intramolecular oxygen coupling mechanism(IMOC)etc.Innovative research progress on the coexistence and transformation of multiple mechanisms is highlighted,and the intrinsic factors that influence these dynamic processes are summarized.Advanced characterization techniques and theoretical modeling are underscored as indispensable tools for revealing these complex interactions.This review provides guiding principles for mechanism-based catalyst design.Finally,in view of the multidimensional challenges currently faced by OER mechanisms,prospects for future research are given to bridge the gap between mechanism innovation and experimental verification and application.This comprehensive review provides valuable perspectives for advancing clean energy technologies and achieving sustainable development.
文摘The author affiliation and the funding information in the Acknowledgement section of the online version of the original article was revised.One affiliation(the 8th affiliation)of the first author is added.The Acknowledgement section of the original article has been revised to:Acknowledgments:This research was funded by the National University of Mongolia under grant agreement P2023(grant number P2023-4578)and supported by the Chey Institute for Advanced Studies“International Scholarship Exchange Fellowship for the academic year of 2024-2025”,Republic of Korea,and the National University of Mongolia.We would like to acknowledge the National University of Mongolia and Soumik Das from the Center for the Study of Regional Development,Jawaharlal Nehru University,New Delhi-110067,for his valuable assistance in preparing the geological maps.
基金the National Natural Science Foundation of China(22108115,22478415,and 21978134)Natural Science Foundation of Jiangsu Province(BK20241744)。
文摘Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium dioxide(M-TiO_(2))/water(H_2O)was developed,and its confinement effect was regulated by changing the pore structure of M-TiO_(2).CO_(2) solubility in the hybrid sorbent was measured experimentally,and the thermodynamic properties including Henry's constant and desorption enthalpy were calculated.Furthermore,the confinement effect in the hybrid sorbent was quantified.Additionally,the hybrid sorbent was recycled with a multi-cycle experiment.The results showed that M-TiO_(2) calcined at 773.2 K(MT500)could lead to an efficient confinement effect.CO_(2) solubility in the hybrid sorbent increased by 49.8%compared to that of H_2O when the mass fraction of[Hmim][NTf_2]/MT500 was 5.0%(mass),where the contribution of confinement effect on Gibbs free energy occupied 5.2%.
基金support from National Natural Science Foundation of China(32101474 and 42377249)National Key Research and Development Program of China(2023YFD2201605).
文摘CO_(2) conversion to CO via the reverse water-gas shift(RWGS)reaction is limited by a low CO_(2) conversion rate and CO selectivity.Herein,an efficient RWGS catalyst is constructed through Enteromorpha prolifera–derived N-rich mesoporous biochar(EPBC)supported atomic-level Cu-Mo_(2)C clusters(Cu-Mo_(2)C/EPBC).Unlike traditional acti-vated carbon(AC)supported Cu-Mo_(2)C particles(Cu-Mo_(2)C/AC),the Cu-Mo_(2)C/EPBC not only presents the better graphitization degree and larger specific surface area,but also uniformly andfirmly anchors atomic-level Cu-Mo_(2)C clusters due to the existence of pyridine nitrogen.Furthermore,the pyridine N of Cu-Mo_(2)C/EPBC strengthens an unblocked electron transfer between Mo_(2)C and Cu clusters,as verified by X-ray absorption spectroscopy.As a result,the synergistic effect between pyridinic N anchoring and the clusters interaction in Cu-Mo_(2)C/EPBC facilitates an improved CO selectivity of 99.95%at 500℃ compared with traditional Cu-Mo_(2)C/AC(99.60%),as well as about 3-fold CO_(2) conversion rate.Density functional theory calculations confirm that pyr-idine N-modified carbon activates the local electronic redistribution at Cu-Mo_(2)C clusters,which contributes to the decreased energy barrier of the transition state of CO^(*)+O^(*)+2H^(*),thereby triggering the transformation of rate-limited step during the redox pathway.This biomass-derived strategy opens perspective on producing sustain-able fuels and building blocks through the RWGS reaction.
基金supported by the Key Project of National Key Research and Development Plan(No.2017YFC0504104)the Program of National Natural Science Foundation of China(No.31670643)
文摘Background: There is a serious lack of experience regarding the productive potential of the natural forests in northeastern China, which severely limits the development of sustainable forest management strategies for this most important forest region in China. Accordingly, the objective of this study is to develop a first comprehensive system for estimating the wood production for the five dominant forest types.Methods: Based on a network of 384 field plots and using the state-space approach, we develop a system of dynamic stand models, for each of the five main forest types. Four models were developed and evaluated, including a base model and three extended models which include the effects of dominant height and climate variables. The four models were fitted, and their predictive strengths were tested, using the "seemingly unrelated regression"(SUR) technique.Results: All three of the extended models increased the accuracy of the predictions at varying degrees for the five major natural forest types of northeastern China. The inclusion of dominant height and two climate factors(precipitation and temperature) in the base model resulted in the best performance for all the forest types. On average, the root mean square values were reduced by 13.0% when compared with the base model.Conclusion: Both dominant height and climate factors were important variables in estimating forest production. This study not only presents a new method for estimating forest production for a large region, but also explains regional differences in the effect of site productivity and climate.
基金supported by The Scientific and Technological Research Council of Turkey(TUBITAK,Grant number:110O928)
文摘Wild forest fires are one of the greatest environmental disasters affecting forest resources. Along the coastal zone of the Mediterranean region in Turkey, forested areas are classified as first-degree, fire-sensitive areas. Every year, thousands of hectares of forests have been destroyed in Turkey. In this study, fire-access zones were determined in the Mediterranean forests of Turkey, by utilizing geographic information systems （GIS） technology. The effective reach distance of fire hoses from both sides of roads was considered in order to delineate fireaccess zones. The effective reach distance can vary based on the technical capabilities and hydraulic capacity of fire trucks （minimum and maximum pressures on water pump）; terrain structures （uphill, downhill and flat）; and ground slope. These factors and their influences were studied in fire sensitive forest areas located in the eastern Mediterranean city of Kahramanmaras in Turkey. First, terrain structures on both sides of the road network and groundslope classes were determined based on GIS data layers. Then, fire access zones were delineated according to water pressure data, terrain structures, and ground-slope classes. The results indicated that 69.30 % of the forested areas were within the fire-access zones, while the rest of the forest was out of reach the fire hoses. The accessible areas were also calculated for forested areas with different fire- sensitivity degrees. The accessible areas were 69.59, 69.96, and 67.16 % for the forested areas that are sensitive to fires at the first, second, and third degrees, respectively. This finding has implications for the monitoring and management of fire threats in areas outside of the reach distance. The outside areas should receive extra attention and monitoring during the fire season so that fires are detected ahead of time and management has sufficient time to react. Besides, new roads should be considered for these areas in order to access more lands in a shorter amount of time.
文摘Forest ecosystems play a crucial role in mitigating global climate change by forming massive carbon sinks. Their carbon stocks and stock changes need to be quantified for carbon budget balancing and international reporting schemes. However, direct sampling and biomass weighing may not always be possible for quantification studies conducted in large forests. In these cases, indirect methods that use forest inventory information combined with remote sensing data can be beneficial. Synthetic aperture radar (SAR) images offer numerous opportunities to researchers as freely distributed remote sensing data. This study aims to estimate the amount of total carbon stock (TCS) in forested lands of the Kizildag Forest Enterprise. To this end, the actual storage capacities of five carbon pools, i.e. above- and below-ground, deadwood, litter, and soil, were calculated using the indirect method based on ground measurements of 264 forest inventory plots. They were then associated with the backscattered values from Sentinel-1 and ALOS-2 PALSAR-2 data in a Geographical Information System (GIS). Finally, TCS was separately modelled and mapped. The best regression model was developed using the HH polarization of ALOS-2 PALSAR-2 with an adjusted R^(2) of 0.78 (p < 0.05). According to the model, the estimated TCS was about 2 Mt for the entire forest, with an average carbon storage of 133 t ha^(−1). The map showed that the distribution of TCS was heterogenic across the study area. Carbon hotspots were mostly composed of pure stands of Anatolian black pine and mixed, over-mature stands of Lebanese cedar and Taurus fir. It was concluded that the total carbon stocks of forest ecosystems could be estimated using appropriate SAR images at acceptable accuracy levels for forestry purposes. The use of additional ancillary data may provide more delicate and reliable estimations in the future. Given the implications of this study, the spatiotemporal dynamics of carbon can be effectively controlled by forest management when coupled with easily accessible space-borne radar data.
基金We appreciate the cooperation of the International Paper from Brazil LTDA(Process 23112.000670/2015-59)Federal University of Sao Carlos and the Brazilian National Council for Scientific and Technological Development(CNPq).
文摘Although the scientific knowledge about some associations between physical parameters of the soil is consolidated,studies focused on investigating the dynamics of forest restoration processes and the structure of soils remain incipient.The study area is located in Cerrado and is called as Private Natural Heritage Reserve(RPPN)Águas Perenes Forest(perennial water forest)and was selected as a“High Conservation Value Forest”,provides scope to investigate the soil physical properties recovery on passive restoration sites,with different ages but with the same land use history.So,the aim was to investigate the soil density,moisture,penetration resistance and infiltration rate with long-term from old(FA,46 year-old),medium(FB,11 year-old)and young(FC,8 year-old)passive restoration sites.It was observed differences in soil density,as well as in soil moisture,resistance to penetration and infiltration rate.Mean densities recorded for FA,FB and FC were 1.38,1.48 and 1.53 g cm^(-3),respectively.FA recorded higher mean soil moisture(14.9%)than FB(11.5%)and FC(10.0%),whereas mean soil resistance to penetration was increased from FA(0.87 MPa)to FB(0.91 MPa)and FC(1.10 MPa).The average infiltration rate was almost similar in FA and FB(FA=76.43 mm h^(-1);FB=77.48 mm h^(-1))and approximately 39%higher than FC(55.79 mm h^(-1)).Thus,although soil density and moisture were different in each passive restoration site,11 year-old passive restoration site showed similar resistance to penetration and infiltration rate to the old(46 years)passive restoration site.These features allowed seeing improvements in hydrological maintenance in the soil and revealed that passive restoration in Cerrado is able to improve the physical features on a soil presenting similar texture,climate and management history.
