Titanium-based semiconductors are known for their high chemical stability and suitable band gap widths.However,the conventional experimental screening methods are inefficient due to the wide variety of materials.To sp...Titanium-based semiconductors are known for their high chemical stability and suitable band gap widths.However,the conventional experimental screening methods are inefficient due to the wide variety of materials.To speed up the selection process,this work focuses on interpretable feature learning and band gap prediction for titanium-based semiconductors.First,titanium compounds were selected from the Materials Project database by machine learning,and elemental features were extracted using the Magpie descriptors.Then,principal component analysis(PCA)was applied to reduce the data dimensionality,creating a representative dataset.Meantime,heatmaps and SHAP(SHapley Additive exPlanations)methods were used to demonstrate the influence of key features such as electronegativity,covalent radius,period number,and unit cell volume on the bandgap,understanding the relationship between the material’s properties and performance.After comparing different machine learning models,including Random Forest(RF),Support Vector Machines(SVM),Linear Regression(LR),and Gradient Boosting Regression(GBR),the RF was found to be the most accurate for band gap prediction.Finally,the model performance was improved through parameter tuning,showing high accuracy.These findings provide strong data support and design guidance for the development of materials in fields like photocatalysis and solar cells.展开更多
国际森林日(International Day of Forests)源于20世纪中叶国际社会对全球森林资源退化的普遍关注。1971年,在欧洲农业联盟于西班牙特内里弗岛召开的大会上,西班牙提出设立“World Forest Day”的倡议并获得一致通过;同年11月,联合国粮...国际森林日(International Day of Forests)源于20世纪中叶国际社会对全球森林资源退化的普遍关注。1971年,在欧洲农业联盟于西班牙特内里弗岛召开的大会上,西班牙提出设立“World Forest Day”的倡议并获得一致通过;同年11月,联合国粮食及农业组织(FAO)正式确认该纪念日。1972年3月21日,首个“World Forest Day”纪念活动得以举办。展开更多
Extreme climate events(e.g.,heatwaves and droughts)are becoming increasingly frequent due to global climate change,which inevitably affects tree growth and various other ecological processes.While the impacts of droug...Extreme climate events(e.g.,heatwaves and droughts)are becoming increasingly frequent due to global climate change,which inevitably affects tree growth and various other ecological processes.While the impacts of droughts on these processes have been widely evaluated,the effects of heatwaves on tree growth and soil water content(SWC)remain poorly understood,particularly those related to thinning treatment.In this study,we evaluated the impacts of the 2021 Pacific Northwest Heatwave and thinning on forest growth and SWC,as well as assessed how thinning might mitigate the heatwave's impacts in lodgepole pine forests in British Columbia,Canada.We measured meteorological data(air temperature,rainfall,solar radiation(SR),relative humidity(RH),and wind speed(W_(s)),sap flow,SWC,soil temperature(T_(s)),and tree diameters at the breast height(DBH)during the growing season(June–September)in the control(27,000 stems·ha^(-1)),lightly thinned(4,500 stems·ha^(-1)),and heavily thinned(1,100 stems·ha^(-1))experimental plots from 2018 to 2024.We found that thinning persistently and significantly(p<0.05)increased individual tree growth,with the most pronounced effects in the heavily thinned stands.The 2021 Pacific Northwest Heatwave led to an exceptionally hot growing season,significantly(p<0.05)reducing forest growth and SWC across all plots.Forest growth recovered in 2022 in the thinned plots but remained suppressed in the unthinned plots,suggesting that thinning effectively mitigated the impact of the heatwave on forest growth,while the heatwave's impacts were persistent in the unthinned plots.Our study highlights that thinning is a practical management strategy for improving tree growth and supporting climate change adaptation to extreme climate events.展开更多
Upper Andean tropical forests are renowned for their extraordinary biodiversity and heterogeneous environmental conditions.Despite the critical role of litter decomposition in carbon and nutrient cycles,its dynamics i...Upper Andean tropical forests are renowned for their extraordinary biodiversity and heterogeneous environmental conditions.Despite the critical role of litter decomposition in carbon and nutrient cycles,its dynamics in this region remains unexplored at finer scales.This study investigates how micro site conditions influence litter decomposition of 15 upper Andean species over time.A reciprocal translocation field experiment was conducted over 18 months in 14 permanent plots within four sites in Colombian Andean mountain forests.Each plot contained three litterbeds(microsites),each with the 15 species,harvested at 3,6,12 and 18 months,totaling 2520 litterbags.Different forest variables,including canopy openness,leaf area index,slope and depth of litter,were measured in each litterbed.ANOVAs and linear mixed models were used to assess variation between sites and plots respectively,while multiple linear regression analyses evaluated the effects of forest variables on decay rates over time at the micro site scale.Results showed differences in absolute decay rates between sites but consistent relative decay rates,indicating varying magnitudes of decomposition,yet maintaining the same order based on their litter quality.Decay rates varied between species,with more variation in labile species compared to recalcitrant ones.Despite substantial variation in forest characteristics within sites,their influence on litter decomposition was minimal and declined over time.This suggests that,at finer spatial scales,the forest microenvironment plays a lesser role in litter decomposition,with litter quality emerging as the primary driver.This study is a step towards understanding the fine-scale dynamics of litter decomposition in upper Andean tropical forests,highlighting the intricate interplay between microenvironmental factors and decomposition processes.展开更多
Temperate forests are vital for maintaining ecological security and regulating the global climate.Despite considerable controversy surrounding the biophysical impacts of temperate forests on mid-latitude temperatures,...Temperate forests are vital for maintaining ecological security and regulating the global climate.Despite considerable controversy surrounding the biophysical impacts of temperate forests on mid-latitude temperatures,we analyzed the effects of forest cover change on local temperature using the Weather Research and Forecasting(WRF)model from 2010 to 2020 in the Greater and Lesser Khingan Mountains(GLKM),Northeastern China,and explored the related driving factors.The conversions between forest and open lands(i.e.,cropland and grassland)were predominant.During the growing season,the conversion of cropland and grassland to forest resulted in warming(0.38±0.10 and 0.41±0.09℃,respectively)in air temperature(Ta),while the reverse conversion caused cooling(-0.31 peratur±0.08 and e-0.24±0.07℃,respectively),which was less than the changes observed in land surface tem(LST).Conversion of forest to impervious land caused warming(1.16 the±0.11℃),and opposite conversion resulted in cooling(can-0.88 t±0.17℃).These results indicate that radiative effects like albedo and net radiation drive the signifi net warming effect from afforestation on open lands within the temperate forest ecoregion.Conversely,conversion to impervious land produced the most substantial net warming impacts,driven by non-radiative effects like sensible heat,latent heat,and ground heat flux(GH).In these conversions,temperature can indirectly influence precipitation(Pre)through vapor pressure deficit(VPD),and Pre can also indirectly affect temperature via evapotranspiration(ET).This study highlights the need to thoroughly understand the impacts of afforestation in temperate forests while avoiding deforestation to regulate the climate effectively.展开更多
Sustainable forest management practices frequently confront the tension between economic viability and conservation objectives,particularly where forests occur in environmentally sensitive zones.The use of skidders in...Sustainable forest management practices frequently confront the tension between economic viability and conservation objectives,particularly where forests occur in environmentally sensitive zones.The use of skidders in protected areas is an essential solution for enabling timber harvesting in environments where the establishment of new skidding trails is either prohibited or highly restricted.These machines are the most used timber extraction machines in Central and Eastern Europe,and cable/adapted skidders are used to increase productivity and to reduce labor.This study compared the work cycles,productivity and costs of four types of skidders working in similar coniferous stands:a dedicated cable skidder,a dedicated cable-grapple skidder,a dedicated grapple skidder and an adapted skidder.The comparison of delay-free work cycles of the four skidders showed the largest share is occupied by travel loaded.The cable-grapple skidder had the highest average speed of 5.6 km h^(-1),followed by the grapple skidder at 3.97 km h^(-1),the cable skidder at 3.79 km h^(-1),and the adapted skidder with an average speed of 3.31 km h^(-1).The average delay-free productivity of the study skidders is highest for the adapted skidder,followed by the grapple skidder with a slightly lower rate,the cable-grapple skidder,and the cable skidder.In conclusion,the average payload of the grapple skidder and the cable grapple skidder is less than the maximum payload of the machine.This is due to the narrow skidding roads and because these skidders are not suitable for the specific site-selective felling with marked single and small groups of trees.The dedicated cable skidders and the adapted cable skidder are very close in productivity.The average productivity of dedicated cable skidders was 17.7 m^(3) h^(-1),while the productivity of the adapted skidder is 14.5 m^(3) h^(-1).Considering this,adapted skidders could be a good solution for improving economic productivity in sensitive forests.展开更多
The study presents an analysis of the spatiotemporal evolution of vegetation cover in the Izarene forest,using LANDSAT satellite images collected for the years 1984,2003,and 2022.The methodological approach is based o...The study presents an analysis of the spatiotemporal evolution of vegetation cover in the Izarene forest,using LANDSAT satellite images collected for the years 1984,2003,and 2022.The methodological approach is based on the use of ArcGIS 10.8 software for processing multispectral images,as well as the calculation of the Normalized Difference Vegetation Index(NDVI),which enables the observation of variations in vegetation cover over time.The findings show that biodiversity is pretty abundant,but they also show that some places with low vegetation density are under a lot of stress.Due in large part to overuse of natural resources,uncontrolled human activity,and environmental factors,these regions seem to be more vulnerable to degradation.However,a decrease in deforestation over the past 20 years is revealed by comparing the two periods(1984–2003 and 2003–2022).The participation of governmental agencies,especially the Department of Water and Forests,through concrete projects like reforestation,forest fire prevention,and awareness-raising campaigns among local communities,is responsible for this progress.In several areas,these measures have stabilized or even improved the state of the vegetation.The analysis emphasizes how crucial sustainable,integrated,and participatory management is to protecting the Izarene forest,which is a significant resource for maintaining the region’s ecological balance.展开更多
This study explores the motivations,perceived benefits,and challenges associated with the adoption of clearcutfree forestry by early adopters among non-industrial private forest(NIPF)owners in southern-central Sweden....This study explores the motivations,perceived benefits,and challenges associated with the adoption of clearcutfree forestry by early adopters among non-industrial private forest(NIPF)owners in southern-central Sweden.Clearcut-free forestry,characterized by continuous tree cover and an emphasis on biodiversity,structural diversity,and ecosystem services(ES),is increasingly seen as a sustainable alternative to conventional intensive management based on short rotations and clear-cutting practices.Based on qualitative interviews with 22 NIPF owners who have adopted this approach,the study provides insights into how these early adopters perceive the value of clearcut-free forestry.Reported motivations include environmental concerns,such as biodiversity conservation and climate resilience,as well as strong socio-cultural values linked to family traditions,aesthetic preferences,and community wellbeing.In this study,we use the multi-level perspective(MLP)framework to conceptualize NIPF owners who have adopted clearcut-free forestry as niche actors and analyze their potential contribution to the emergence of an alternative forest management regime.The findings highlight that early adopters associate multiple benefits with clearcut-free forestry,encompassing enhanced ecosystem services such as carbon sequestration,water regulation,habitat preservation,and socio-cultural enrichment through recreation and relational values.However,the interviewees identify several interrelated challenges,including knowledge gaps,lack of clear definitions and standardized practices,limited advisory services,underdeveloped value chains for high-quality timber,and market barriers,which hinder more widespread adoption.Within the multi-level perspective,owner perceptions linking clearcut-free management with improved forest multifunctionality serve as a key driver of niche-level experimentation.This suggests an alignment between these owners and evolving societal demands for more inclusive,sustainable,and diversified forest use.Policy recommendations include targeted investments in knowledge co-production,infrastructure,market incentives,and certification schemes to support the economic viability and broader adoption of clearcut-free forestry.展开更多
Frequent droughts pose considerable threat to global forest carbon uptake,but little is known about the response of forest carbon fluxes in climatic transition zones to seasonal drought.In this study,the responses of ...Frequent droughts pose considerable threat to global forest carbon uptake,but little is known about the response of forest carbon fluxes in climatic transition zones to seasonal drought.In this study,the responses of carbon fluxes to seasonal drought in two natural forests(Quercus aliena var.acute serrata Maxim and Pinus tabuliformis Carr.)in the Baotianman Nature Reserve were investigated.The Q.aliena forest exhibited a high resilience with stable gross primary productivity(GPP).However,ecosystem respiration(Re)significantly declined by 18.4%compared with normal years,leading to an increase in net carbon sequestration capacity of 4.1%.This resilience was attributed to its deep root system accessing soil water(SWC_(50cm))to sustain stomatal openness,coupled with the efficient utilization of photosynthetically active radiation to drive photosynthesis.In contrast,the P.tabuliformis forest,which relied on shallow soil moisture(SWC_(20cm)),experienced simultaneous decreases in both GPP and Re during drought,with a sharply greater decrease in GPP,resulting in low net carbon sink capacity.Further analysis revealed that the Q.aliena forest prioritized carbon assimilation through a deep water-stomatal synergy strategy(anisohydric behavior),whereas the P.tabuliformis forest adopted an isohydric strategy favoring water conservation at the expense of carbon fixation efficiency.These findings highlight distinct mechanisms underlying drought adaptation between forest types,providing critical insight into optimizing forest carbon cycle models and selecting drought-resistant species under the influence of climate change.展开更多
CHINA Wuliangshan National Nature Reserve Spanning a significant altitudinal range from 1,600 to 3,371 metres and encompassing a total area of 31,585 hectares,the Wuliangshan National Nature Reserve protects one of th...CHINA Wuliangshan National Nature Reserve Spanning a significant altitudinal range from 1,600 to 3,371 metres and encompassing a total area of 31,585 hectares,the Wuliangshan National Nature Reserve protects one of the most intact and pristine forest ecosystems in southern Yunnan Province.展开更多
Soil fertility and forest structure influence tree carbon stocks.However,it remains unclear how tree mycorrhizal types affect these relationships.This study addressed the question of how aboveground and belowground tr...Soil fertility and forest structure influence tree carbon stocks.However,it remains unclear how tree mycorrhizal types affect these relationships.This study addressed the question of how aboveground and belowground tree carbon stocks in soils with different mycorrhizal types are affected by soil fertility and forest structure.Tree demographic data were used from a 21.12-ha study area collected over a ten-year period(2009-2019),covering 43species of woody plants and more than 50,000 individuals.Relationships between tree carbon stock,soil fertility and forest structure(stand density,diameter variation,species diversity and spatial distribution)were examined,as well as whether these relationships differed between arbuscular mycorrhiza and ectomycorrhizal mycorrhiza groups in a typical temperate conifer and broad-leaved mixed forest.We found that total tree carbon stock was positively impacted by variations in stand density and tree diameter but negatively influenced by soil fertility,tree species diversity and uniform angle index.Soil fertility promoted carbon stock of trees associated with arbuscular mycorrhiza(AM)but inhibited the carbon stock of trees with ectomycorrhizal mycorrhiza fungi(EcM).Carbon stock of AM trees was mainly influenced by soil fertility,while carbon stock of EcM trees was influenced by stand density.Our findings show that mycorrhizae types mediate the impact of stand structure and soil fertility on tree carbon stocks and provides new evidence on how forest tree carbon stocks may be enhanced based on the types of mycorrhizal associations.Tree species with different mycorrhizal types can be managed in different ways.展开更多
Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 s...Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests.展开更多
Subtropical evergreen sub-montane forests in Punjab,Pakistan,are vital for carbon sequestration and play an essential role in supporting local communities.While the global importance of tree species diversity in enhan...Subtropical evergreen sub-montane forests in Punjab,Pakistan,are vital for carbon sequestration and play an essential role in supporting local communities.While the global importance of tree species diversity in enhancing aboveground carbon(AGC)storage is well established,there remains limited empirical evidence from Pakistan’s forest ecosystems.This study investigated how taxonomic and functional diversity,alongside topographical variables,influence AGC across four districts in Punjab.Taxonomic metrics such as the Importance Value Index(IVI)and genus richness were computed,along with functional diversity indices including functional richness(FRic),functional dispersion(FDis),functional divergence(FDiv),and functional evenness(FEve).AGC was estimated using species-specific allometric equations,and linear mixed-effects models were applied to identify the most influential predictors.Acacia modesta and A.nilotica emerged as the dominant species in the studied sites.While species richness and biomass increased with elevation,Shannon diversity showed a negative relationship with elevation.AGC values ranged from 100 to 350 Mg ha⁻¹across the study sites.Among diversity metrics,FRic(0.042)and FDis(0.342)were significantly associated with higher AGC,whereas taxonomic diversity measures showed weaker correlations.Although elevation was a strong predictor of diversity patterns,it did not have a significant direct effect on carbon storage.These findings underscore the importance of incorporating functional trait diversity and topographic variability into forest management strategies to enhance carbon sequestration,strengthen ecosystem resilience and support sustainable rural livelihoods.展开更多
Understanding how genetic variation within forest species influences growth responses under climate change is essential for improving the accuracy of forest models and guiding adaptive management strategies.This study...Understanding how genetic variation within forest species influences growth responses under climate change is essential for improving the accuracy of forest models and guiding adaptive management strategies.This study models the dynamics of Italian silver fir(Abies alba)forests under varying climate change scenarios using the forest gap model FORMIND.Focusing on three distinct silver fir provenances(Western Alps,Northern Apennines,and Southern Apennines),the study simulates forest growth in the Tuscan-Emilian Apennine National Park under different representative concentration pathways(RCPs).The individual-based model FORMIND was parameterized and validated with field data for each of the provenances,demonstrating its ability to accurately reproduce key forest metrics and dynamics.Our results reveal significant differences in expected growth patterns,productivity,metabolism,and carbon storage capacity among the silver fir provenances in pure and mixed stands.In the simulations,the Northern Apennines provenance showed higher biomass production(biomass>10%±1%)and carbon uptake(net primary productivity,NPP>8%±1%)at the end of the century compared to the Western Alps provenance in the pure provenance(PP)and no regeneration scenario.Conversely,the Southern Apennines provenance showed higher biomass(biomass>5%–10%)and NPP(>15%–18%)in mixed provenance(MP)and regeneration scenarios.These results show that genetic diversity strongly affects forest growth and resilience to environmental changes.Hence,it should be included as a predictor variable in forest models.The study also demonstrates the resilience of silver fir to climatic stressors,emphasizing its potential as a robust species in multiple forest contexts.The integration of forest provenance data into the FORMIND model represents a significant advancement in forest modelling,enabling more accurate and reliable predictions under climate change scenarios.The study's findings advocate for a greater understanding and consideration of genetic diversity in forest management and conservation strategies,in support of assisted migration strategies aiming to enhance the resilience of forest ecosystems in a changing climate.展开更多
Stand age plays a crucial role in forest biomass estimation and carbon cycle modeling.Assessing the uncertainty of stand age prediction models and identifying the key driving factors in the modeling process have becom...Stand age plays a crucial role in forest biomass estimation and carbon cycle modeling.Assessing the uncertainty of stand age prediction models and identifying the key driving factors in the modeling process have become major challenges in forestry research.In this study,we selected the Shaanxi-Gansu-Ningxia region of Northeast China as the research area and utilized multi-source datasets from the summer of 2019 to extract information on spectral,textural,climatic,water balance,and stand characteristics.By integrating the Random Forest(RF)model with Monte Carlo(MC)simulation,we constructed six regression models based on different combina-tions of features and evaluated the uncertainty of each model.Furthermore,we investigated the driving factors influencing stand age modeling by analyzing the effects of different types of features on age inversion.Model performance and accuracy were assessed using the root mean square error(RMSE),mean absolute error(MAE),and the coefficient of determination(R^(2)),while the relative root mean square error(rRMSE)was employed to quantify model uncertainty.The results indicate that the scenarios with more obvious improve-ment in accuracy and effective reduction in uncertainty were Scenario 3 with the inclusion of climate and water balance information(RMSE=25.54 yr,MAE=18.03 yr,R^(2)=0.51,rRMSE=19.17%)and Scenario 5 with the inclusion of stand characterization informa-tion(RMSE=18.47 yr,MAE=13.05 yr,R^(2)=0.74,rRMSE=16.99%).Scenario 6,incorporating all feature types,achieved the highest accuracy(RMSE=17.60 yr,MAE=12.06 yr,R^(2)=0.77,rRMSE=14.19%).In this study,elevation,minimum temperature,and diameter at breast height(DBH)emerged as the key drivers of stand-age modeling.The proposed method can be used to identify drivers and to quantify uncertainty in stand-age estimation,providing a useful reference for improving model accuracy and uncertainty assessment.展开更多
The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang...The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang for multiple years via a decision tree method based on a classification and regression tree(CART)algorithm using Landsat time series images.Spatiotemporal transform and fragmentation patterns of mangrove distribution were separately assessed with a transfer matrix of land cover types and a landscape pattern index.The classification method combined with multi-band images showed good accuracy,with overall accuracy higher than 90%.Mangrove areas in 1988,1999,2009,and 2019 were 2050,1875,1818,and 1750 ha,respectively,with decreases mainly due to conversion to aquaculture ponds and farmland.A mangrove growth index(MGI)was proposed,reflecting the water-mangrove relationship,showing positive mangrove growth from 1988–2009 and negative growth from 2009–2019.Study results indicated anthropogenic factors play a leading role in the extent and scale of mangrove effects over the past 30 years.According to the analysis results,corresponding management and protection measures are proposed to provide reference for the sustainable development of Dongzhaigang Mangrove Wetland ecosystem.展开更多
Remote sensing plays a pivotal role in forest inventory by enabling efficient large-scale monitoring while minimizing fieldwork costs.However,missing values pose a critical challenge in remote sensing applications,as ...Remote sensing plays a pivotal role in forest inventory by enabling efficient large-scale monitoring while minimizing fieldwork costs.However,missing values pose a critical challenge in remote sensing applications,as ignoring or mishandling such data gaps can introduce systematic bias into the estimation of target variables for natural resource monitoring.This can lead to cascading errors that propagate through forest and ecosystem management decisions,ultimately hindering progress toward sustainable forest management,biodiversity conservation,and climate change mitigation strategies.This study aims to propose and demonstrate a procedure that employs hybrid estimators to address the limitations of missing remotely sensed data in forest inventory,using Landsat 7 ETM+SLC-off data as an archived source for forest resource monitoring as a case in point.We compared forest inventory estimates from the hybrid estimator with those from a conventional model-based(CMB)estimator using Sentinel-2 data without missing values.Monte Carlo simulations revealed three key findings:(1)The hybrid estimator,leveraging missing-data remote sensing represented by Landsat 7 ETM+SLCoff data,achieved a sampling precision of over 90%,meeting China's national standard for the National Forest Inventory(NFI);(2)The hybrid estimator demonstrated comparable efficiency to the CMB estimator;(3)The uncertainty associated with hybrid estimators was primarily dominated by model parameter estimation,which could be effectively mitigated by slightly increasing the training sample size or refining model specification.Overall,in forest inventory,the hybrid estimator can surmount the limitations posed by missing values in remotely sensed auxiliary data,effectively balancing cost-effectiveness and flexibility.展开更多
Reforestation initiatives are often limited by insufficient seeds,a problem exacerbated by natural variability in tree flowering and seed production and climate change and other environmental challenges.Innovative and...Reforestation initiatives are often limited by insufficient seeds,a problem exacerbated by natural variability in tree flowering and seed production and climate change and other environmental challenges.Innovative and adaptive solutions such as in vitro propagation are thus needed.Tissue culture can provide high-quality propagation material for tree conservation and mass propagation,but faces technical,economic,regulatory,and social barriers.Obstacles related to the academia-industry interface and to stakeholder concerns are discussed and actions suggested to overcome these barriers to realize the full potential of tree micropropagation.These include refining techniques to improve efficiency and reduce costs;establishing collaborations among researchers,industry,and foresters;and reducing points of contention and misinformation regarding genetic diversity and public perception.International collaborative initiatives,exemplified by the EU COST Action CA21157 COPYTREE,are elementary for achieving these goals.展开更多
文摘Titanium-based semiconductors are known for their high chemical stability and suitable band gap widths.However,the conventional experimental screening methods are inefficient due to the wide variety of materials.To speed up the selection process,this work focuses on interpretable feature learning and band gap prediction for titanium-based semiconductors.First,titanium compounds were selected from the Materials Project database by machine learning,and elemental features were extracted using the Magpie descriptors.Then,principal component analysis(PCA)was applied to reduce the data dimensionality,creating a representative dataset.Meantime,heatmaps and SHAP(SHapley Additive exPlanations)methods were used to demonstrate the influence of key features such as electronegativity,covalent radius,period number,and unit cell volume on the bandgap,understanding the relationship between the material’s properties and performance.After comparing different machine learning models,including Random Forest(RF),Support Vector Machines(SVM),Linear Regression(LR),and Gradient Boosting Regression(GBR),the RF was found to be the most accurate for band gap prediction.Finally,the model performance was improved through parameter tuning,showing high accuracy.These findings provide strong data support and design guidance for the development of materials in fields like photocatalysis and solar cells.
文摘国际森林日(International Day of Forests)源于20世纪中叶国际社会对全球森林资源退化的普遍关注。1971年,在欧洲农业联盟于西班牙特内里弗岛召开的大会上,西班牙提出设立“World Forest Day”的倡议并获得一致通过;同年11月,联合国粮食及农业组织(FAO)正式确认该纪念日。1972年3月21日,首个“World Forest Day”纪念活动得以举办。
基金supported by the British Columbia Ministry of Forces through long-term annual contracts with University of British Columbia(Okanagan)(No.RE25SIR242)the Natural Sciences and Engineering Research Council of Canada(NSERC),Discovery Grants Program(No.RGPIN-2021-02628)+1 种基金supported by the China Postdoctoral Science Foundation(No.2024M760387)Heilongjiang Postdoctoral Financial Assistance(No.LBH-Z24062)。
文摘Extreme climate events(e.g.,heatwaves and droughts)are becoming increasingly frequent due to global climate change,which inevitably affects tree growth and various other ecological processes.While the impacts of droughts on these processes have been widely evaluated,the effects of heatwaves on tree growth and soil water content(SWC)remain poorly understood,particularly those related to thinning treatment.In this study,we evaluated the impacts of the 2021 Pacific Northwest Heatwave and thinning on forest growth and SWC,as well as assessed how thinning might mitigate the heatwave's impacts in lodgepole pine forests in British Columbia,Canada.We measured meteorological data(air temperature,rainfall,solar radiation(SR),relative humidity(RH),and wind speed(W_(s)),sap flow,SWC,soil temperature(T_(s)),and tree diameters at the breast height(DBH)during the growing season(June–September)in the control(27,000 stems·ha^(-1)),lightly thinned(4,500 stems·ha^(-1)),and heavily thinned(1,100 stems·ha^(-1))experimental plots from 2018 to 2024.We found that thinning persistently and significantly(p<0.05)increased individual tree growth,with the most pronounced effects in the heavily thinned stands.The 2021 Pacific Northwest Heatwave led to an exceptionally hot growing season,significantly(p<0.05)reducing forest growth and SWC across all plots.Forest growth recovered in 2022 in the thinned plots but remained suppressed in the unthinned plots,suggesting that thinning effectively mitigated the impact of the heatwave on forest growth,while the heatwave's impacts were persistent in the unthinned plots.Our study highlights that thinning is a practical management strategy for improving tree growth and supporting climate change adaptation to extreme climate events.
基金supported by the Universidad del Rosario(Small grant ID:IV-FPD003)。
文摘Upper Andean tropical forests are renowned for their extraordinary biodiversity and heterogeneous environmental conditions.Despite the critical role of litter decomposition in carbon and nutrient cycles,its dynamics in this region remains unexplored at finer scales.This study investigates how micro site conditions influence litter decomposition of 15 upper Andean species over time.A reciprocal translocation field experiment was conducted over 18 months in 14 permanent plots within four sites in Colombian Andean mountain forests.Each plot contained three litterbeds(microsites),each with the 15 species,harvested at 3,6,12 and 18 months,totaling 2520 litterbags.Different forest variables,including canopy openness,leaf area index,slope and depth of litter,were measured in each litterbed.ANOVAs and linear mixed models were used to assess variation between sites and plots respectively,while multiple linear regression analyses evaluated the effects of forest variables on decay rates over time at the micro site scale.Results showed differences in absolute decay rates between sites but consistent relative decay rates,indicating varying magnitudes of decomposition,yet maintaining the same order based on their litter quality.Decay rates varied between species,with more variation in labile species compared to recalcitrant ones.Despite substantial variation in forest characteristics within sites,their influence on litter decomposition was minimal and declined over time.This suggests that,at finer spatial scales,the forest microenvironment plays a lesser role in litter decomposition,with litter quality emerging as the primary driver.This study is a step towards understanding the fine-scale dynamics of litter decomposition in upper Andean tropical forests,highlighting the intricate interplay between microenvironmental factors and decomposition processes.
基金funded or supported by the National Natural Science Foundation of China(Nos.32371878,32001251)the Natural Science Foundation of Jiangsu Province(No.BK20200781)+1 种基金the Youth Science and Technology Talent Lifting Project of Jiangsu Province(No.JSTJ-2024-324)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Temperate forests are vital for maintaining ecological security and regulating the global climate.Despite considerable controversy surrounding the biophysical impacts of temperate forests on mid-latitude temperatures,we analyzed the effects of forest cover change on local temperature using the Weather Research and Forecasting(WRF)model from 2010 to 2020 in the Greater and Lesser Khingan Mountains(GLKM),Northeastern China,and explored the related driving factors.The conversions between forest and open lands(i.e.,cropland and grassland)were predominant.During the growing season,the conversion of cropland and grassland to forest resulted in warming(0.38±0.10 and 0.41±0.09℃,respectively)in air temperature(Ta),while the reverse conversion caused cooling(-0.31 peratur±0.08 and e-0.24±0.07℃,respectively),which was less than the changes observed in land surface tem(LST).Conversion of forest to impervious land caused warming(1.16 the±0.11℃),and opposite conversion resulted in cooling(can-0.88 t±0.17℃).These results indicate that radiative effects like albedo and net radiation drive the signifi net warming effect from afforestation on open lands within the temperate forest ecoregion.Conversely,conversion to impervious land produced the most substantial net warming impacts,driven by non-radiative effects like sensible heat,latent heat,and ground heat flux(GH).In these conversions,temperature can indirectly influence precipitation(Pre)through vapor pressure deficit(VPD),and Pre can also indirectly affect temperature via evapotranspiration(ET).This study highlights the need to thoroughly understand the impacts of afforestation in temperate forests while avoiding deforestation to regulate the climate effectively.
基金supported by the inter-institutional agreement between the University of Forestry (Bulgaria)the Mediterranean University of Reggio Calabria (Italy)by the Ph.D. course “Agricultural, Food and Forestry Science” of the Mediterranean University of Reggio Calabria (Italy)—XXXIX cycle。
文摘Sustainable forest management practices frequently confront the tension between economic viability and conservation objectives,particularly where forests occur in environmentally sensitive zones.The use of skidders in protected areas is an essential solution for enabling timber harvesting in environments where the establishment of new skidding trails is either prohibited or highly restricted.These machines are the most used timber extraction machines in Central and Eastern Europe,and cable/adapted skidders are used to increase productivity and to reduce labor.This study compared the work cycles,productivity and costs of four types of skidders working in similar coniferous stands:a dedicated cable skidder,a dedicated cable-grapple skidder,a dedicated grapple skidder and an adapted skidder.The comparison of delay-free work cycles of the four skidders showed the largest share is occupied by travel loaded.The cable-grapple skidder had the highest average speed of 5.6 km h^(-1),followed by the grapple skidder at 3.97 km h^(-1),the cable skidder at 3.79 km h^(-1),and the adapted skidder with an average speed of 3.31 km h^(-1).The average delay-free productivity of the study skidders is highest for the adapted skidder,followed by the grapple skidder with a slightly lower rate,the cable-grapple skidder,and the cable skidder.In conclusion,the average payload of the grapple skidder and the cable grapple skidder is less than the maximum payload of the machine.This is due to the narrow skidding roads and because these skidders are not suitable for the specific site-selective felling with marked single and small groups of trees.The dedicated cable skidders and the adapted cable skidder are very close in productivity.The average productivity of dedicated cable skidders was 17.7 m^(3) h^(-1),while the productivity of the adapted skidder is 14.5 m^(3) h^(-1).Considering this,adapted skidders could be a good solution for improving economic productivity in sensitive forests.
文摘The study presents an analysis of the spatiotemporal evolution of vegetation cover in the Izarene forest,using LANDSAT satellite images collected for the years 1984,2003,and 2022.The methodological approach is based on the use of ArcGIS 10.8 software for processing multispectral images,as well as the calculation of the Normalized Difference Vegetation Index(NDVI),which enables the observation of variations in vegetation cover over time.The findings show that biodiversity is pretty abundant,but they also show that some places with low vegetation density are under a lot of stress.Due in large part to overuse of natural resources,uncontrolled human activity,and environmental factors,these regions seem to be more vulnerable to degradation.However,a decrease in deforestation over the past 20 years is revealed by comparing the two periods(1984–2003 and 2003–2022).The participation of governmental agencies,especially the Department of Water and Forests,through concrete projects like reforestation,forest fire prevention,and awareness-raising campaigns among local communities,is responsible for this progress.In several areas,these measures have stabilized or even improved the state of the vegetation.The analysis emphasizes how crucial sustainable,integrated,and participatory management is to protecting the Izarene forest,which is a significant resource for maintaining the region’s ecological balance.
基金financed by a grant from Mistra[DIA 2019/28]and from Formas via the National Research Programme on Climate(2021–00416)FORMAS,Grant Nos.2022-02146 and 2021–01067Swedish Environmental Protection Agency Research Grant No.2021–00040。
文摘This study explores the motivations,perceived benefits,and challenges associated with the adoption of clearcutfree forestry by early adopters among non-industrial private forest(NIPF)owners in southern-central Sweden.Clearcut-free forestry,characterized by continuous tree cover and an emphasis on biodiversity,structural diversity,and ecosystem services(ES),is increasingly seen as a sustainable alternative to conventional intensive management based on short rotations and clear-cutting practices.Based on qualitative interviews with 22 NIPF owners who have adopted this approach,the study provides insights into how these early adopters perceive the value of clearcut-free forestry.Reported motivations include environmental concerns,such as biodiversity conservation and climate resilience,as well as strong socio-cultural values linked to family traditions,aesthetic preferences,and community wellbeing.In this study,we use the multi-level perspective(MLP)framework to conceptualize NIPF owners who have adopted clearcut-free forestry as niche actors and analyze their potential contribution to the emergence of an alternative forest management regime.The findings highlight that early adopters associate multiple benefits with clearcut-free forestry,encompassing enhanced ecosystem services such as carbon sequestration,water regulation,habitat preservation,and socio-cultural enrichment through recreation and relational values.However,the interviewees identify several interrelated challenges,including knowledge gaps,lack of clear definitions and standardized practices,limited advisory services,underdeveloped value chains for high-quality timber,and market barriers,which hinder more widespread adoption.Within the multi-level perspective,owner perceptions linking clearcut-free management with improved forest multifunctionality serve as a key driver of niche-level experimentation.This suggests an alignment between these owners and evolving societal demands for more inclusive,sustainable,and diversified forest use.Policy recommendations include targeted investments in knowledge co-production,infrastructure,market incentives,and certification schemes to support the economic viability and broader adoption of clearcut-free forestry.
基金financially supported by the National Key Research and Development Program of China(2021YFD2200405)the National Natural Science Foundation of China(31930078)special funds for Baotianman Forest Ecosystem Research Station from Chinese Academy of Forestry and Ministry of Science and Technology of China。
文摘Frequent droughts pose considerable threat to global forest carbon uptake,but little is known about the response of forest carbon fluxes in climatic transition zones to seasonal drought.In this study,the responses of carbon fluxes to seasonal drought in two natural forests(Quercus aliena var.acute serrata Maxim and Pinus tabuliformis Carr.)in the Baotianman Nature Reserve were investigated.The Q.aliena forest exhibited a high resilience with stable gross primary productivity(GPP).However,ecosystem respiration(Re)significantly declined by 18.4%compared with normal years,leading to an increase in net carbon sequestration capacity of 4.1%.This resilience was attributed to its deep root system accessing soil water(SWC_(50cm))to sustain stomatal openness,coupled with the efficient utilization of photosynthetically active radiation to drive photosynthesis.In contrast,the P.tabuliformis forest,which relied on shallow soil moisture(SWC_(20cm)),experienced simultaneous decreases in both GPP and Re during drought,with a sharply greater decrease in GPP,resulting in low net carbon sink capacity.Further analysis revealed that the Q.aliena forest prioritized carbon assimilation through a deep water-stomatal synergy strategy(anisohydric behavior),whereas the P.tabuliformis forest adopted an isohydric strategy favoring water conservation at the expense of carbon fixation efficiency.These findings highlight distinct mechanisms underlying drought adaptation between forest types,providing critical insight into optimizing forest carbon cycle models and selecting drought-resistant species under the influence of climate change.
文摘CHINA Wuliangshan National Nature Reserve Spanning a significant altitudinal range from 1,600 to 3,371 metres and encompassing a total area of 31,585 hectares,the Wuliangshan National Nature Reserve protects one of the most intact and pristine forest ecosystems in southern Yunnan Province.
基金supported by the Science and Technology Project of the Department of Transportation of Heilongjiang Province(HJK2023B024-3)the National Key R&D Program of China(2023YFF1304001-01)。
文摘Soil fertility and forest structure influence tree carbon stocks.However,it remains unclear how tree mycorrhizal types affect these relationships.This study addressed the question of how aboveground and belowground tree carbon stocks in soils with different mycorrhizal types are affected by soil fertility and forest structure.Tree demographic data were used from a 21.12-ha study area collected over a ten-year period(2009-2019),covering 43species of woody plants and more than 50,000 individuals.Relationships between tree carbon stock,soil fertility and forest structure(stand density,diameter variation,species diversity and spatial distribution)were examined,as well as whether these relationships differed between arbuscular mycorrhiza and ectomycorrhizal mycorrhiza groups in a typical temperate conifer and broad-leaved mixed forest.We found that total tree carbon stock was positively impacted by variations in stand density and tree diameter but negatively influenced by soil fertility,tree species diversity and uniform angle index.Soil fertility promoted carbon stock of trees associated with arbuscular mycorrhiza(AM)but inhibited the carbon stock of trees with ectomycorrhizal mycorrhiza fungi(EcM).Carbon stock of AM trees was mainly influenced by soil fertility,while carbon stock of EcM trees was influenced by stand density.Our findings show that mycorrhizae types mediate the impact of stand structure and soil fertility on tree carbon stocks and provides new evidence on how forest tree carbon stocks may be enhanced based on the types of mycorrhizal associations.Tree species with different mycorrhizal types can be managed in different ways.
基金supported by the National Natural Science Foundation of China(32460380,42007042)State Key Laboratory of Subtropical Silviculture(SKLSSKF2023-06)+2 种基金Natural Science Foundation of Jiangxi Province(20242BAB25389)National Undergraduate Innovation and Entrepreneurship Training Program(202410410029X)Jiangxi Province Graduate Student Innovation Special Fund Project(YC2024-S330).
文摘Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests.
文摘Subtropical evergreen sub-montane forests in Punjab,Pakistan,are vital for carbon sequestration and play an essential role in supporting local communities.While the global importance of tree species diversity in enhancing aboveground carbon(AGC)storage is well established,there remains limited empirical evidence from Pakistan’s forest ecosystems.This study investigated how taxonomic and functional diversity,alongside topographical variables,influence AGC across four districts in Punjab.Taxonomic metrics such as the Importance Value Index(IVI)and genus richness were computed,along with functional diversity indices including functional richness(FRic),functional dispersion(FDis),functional divergence(FDiv),and functional evenness(FEve).AGC was estimated using species-specific allometric equations,and linear mixed-effects models were applied to identify the most influential predictors.Acacia modesta and A.nilotica emerged as the dominant species in the studied sites.While species richness and biomass increased with elevation,Shannon diversity showed a negative relationship with elevation.AGC values ranged from 100 to 350 Mg ha⁻¹across the study sites.Among diversity metrics,FRic(0.042)and FDis(0.342)were significantly associated with higher AGC,whereas taxonomic diversity measures showed weaker correlations.Although elevation was a strong predictor of diversity patterns,it did not have a significant direct effect on carbon storage.These findings underscore the importance of incorporating functional trait diversity and topographic variability into forest management strategies to enhance carbon sequestration,strengthen ecosystem resilience and support sustainable rural livelihoods.
基金the University of Milan for funding the“ProForesta”project through the 2020 Research Support Planthe“Ente Parco Nazionale dell'Appennino Tosco-Emiliano”for having financed the project“First urgent measures to promote the adaptation of the silver fir forests of the Tuscan-Emilian Apennine National Park to the effects of climate change”。
文摘Understanding how genetic variation within forest species influences growth responses under climate change is essential for improving the accuracy of forest models and guiding adaptive management strategies.This study models the dynamics of Italian silver fir(Abies alba)forests under varying climate change scenarios using the forest gap model FORMIND.Focusing on three distinct silver fir provenances(Western Alps,Northern Apennines,and Southern Apennines),the study simulates forest growth in the Tuscan-Emilian Apennine National Park under different representative concentration pathways(RCPs).The individual-based model FORMIND was parameterized and validated with field data for each of the provenances,demonstrating its ability to accurately reproduce key forest metrics and dynamics.Our results reveal significant differences in expected growth patterns,productivity,metabolism,and carbon storage capacity among the silver fir provenances in pure and mixed stands.In the simulations,the Northern Apennines provenance showed higher biomass production(biomass>10%±1%)and carbon uptake(net primary productivity,NPP>8%±1%)at the end of the century compared to the Western Alps provenance in the pure provenance(PP)and no regeneration scenario.Conversely,the Southern Apennines provenance showed higher biomass(biomass>5%–10%)and NPP(>15%–18%)in mixed provenance(MP)and regeneration scenarios.These results show that genetic diversity strongly affects forest growth and resilience to environmental changes.Hence,it should be included as a predictor variable in forest models.The study also demonstrates the resilience of silver fir to climatic stressors,emphasizing its potential as a robust species in multiple forest contexts.The integration of forest provenance data into the FORMIND model represents a significant advancement in forest modelling,enabling more accurate and reliable predictions under climate change scenarios.The study's findings advocate for a greater understanding and consideration of genetic diversity in forest management and conservation strategies,in support of assisted migration strategies aiming to enhance the resilience of forest ecosystems in a changing climate.
基金Under the auspices of the Natural Science Foundation of China(No.32371875,32001249)。
文摘Stand age plays a crucial role in forest biomass estimation and carbon cycle modeling.Assessing the uncertainty of stand age prediction models and identifying the key driving factors in the modeling process have become major challenges in forestry research.In this study,we selected the Shaanxi-Gansu-Ningxia region of Northeast China as the research area and utilized multi-source datasets from the summer of 2019 to extract information on spectral,textural,climatic,water balance,and stand characteristics.By integrating the Random Forest(RF)model with Monte Carlo(MC)simulation,we constructed six regression models based on different combina-tions of features and evaluated the uncertainty of each model.Furthermore,we investigated the driving factors influencing stand age modeling by analyzing the effects of different types of features on age inversion.Model performance and accuracy were assessed using the root mean square error(RMSE),mean absolute error(MAE),and the coefficient of determination(R^(2)),while the relative root mean square error(rRMSE)was employed to quantify model uncertainty.The results indicate that the scenarios with more obvious improve-ment in accuracy and effective reduction in uncertainty were Scenario 3 with the inclusion of climate and water balance information(RMSE=25.54 yr,MAE=18.03 yr,R^(2)=0.51,rRMSE=19.17%)and Scenario 5 with the inclusion of stand characterization informa-tion(RMSE=18.47 yr,MAE=13.05 yr,R^(2)=0.74,rRMSE=16.99%).Scenario 6,incorporating all feature types,achieved the highest accuracy(RMSE=17.60 yr,MAE=12.06 yr,R^(2)=0.77,rRMSE=14.19%).In this study,elevation,minimum temperature,and diameter at breast height(DBH)emerged as the key drivers of stand-age modeling.The proposed method can be used to identify drivers and to quantify uncertainty in stand-age estimation,providing a useful reference for improving model accuracy and uncertainty assessment.
基金financially supported by the National Natural Science Foundation of China(Nos.U2244225 and 42020104005)the Ministry of Education of China(111 Project)the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)and China Geological Survey(No.DD20211391)。
文摘The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang for multiple years via a decision tree method based on a classification and regression tree(CART)algorithm using Landsat time series images.Spatiotemporal transform and fragmentation patterns of mangrove distribution were separately assessed with a transfer matrix of land cover types and a landscape pattern index.The classification method combined with multi-band images showed good accuracy,with overall accuracy higher than 90%.Mangrove areas in 1988,1999,2009,and 2019 were 2050,1875,1818,and 1750 ha,respectively,with decreases mainly due to conversion to aquaculture ponds and farmland.A mangrove growth index(MGI)was proposed,reflecting the water-mangrove relationship,showing positive mangrove growth from 1988–2009 and negative growth from 2009–2019.Study results indicated anthropogenic factors play a leading role in the extent and scale of mangrove effects over the past 30 years.According to the analysis results,corresponding management and protection measures are proposed to provide reference for the sustainable development of Dongzhaigang Mangrove Wetland ecosystem.
基金supported by the National Key R&D Program of China(No.2023YFF1304002-05)the National Social Science Fund of China(No.22BTJ005)the National Natural Science Foundation of China(No.32572049)。
文摘Remote sensing plays a pivotal role in forest inventory by enabling efficient large-scale monitoring while minimizing fieldwork costs.However,missing values pose a critical challenge in remote sensing applications,as ignoring or mishandling such data gaps can introduce systematic bias into the estimation of target variables for natural resource monitoring.This can lead to cascading errors that propagate through forest and ecosystem management decisions,ultimately hindering progress toward sustainable forest management,biodiversity conservation,and climate change mitigation strategies.This study aims to propose and demonstrate a procedure that employs hybrid estimators to address the limitations of missing remotely sensed data in forest inventory,using Landsat 7 ETM+SLC-off data as an archived source for forest resource monitoring as a case in point.We compared forest inventory estimates from the hybrid estimator with those from a conventional model-based(CMB)estimator using Sentinel-2 data without missing values.Monte Carlo simulations revealed three key findings:(1)The hybrid estimator,leveraging missing-data remote sensing represented by Landsat 7 ETM+SLCoff data,achieved a sampling precision of over 90%,meeting China's national standard for the National Forest Inventory(NFI);(2)The hybrid estimator demonstrated comparable efficiency to the CMB estimator;(3)The uncertainty associated with hybrid estimators was primarily dominated by model parameter estimation,which could be effectively mitigated by slightly increasing the training sample size or refining model specification.Overall,in forest inventory,the hybrid estimator can surmount the limitations posed by missing values in remotely sensed auxiliary data,effectively balancing cost-effectiveness and flexibility.
基金funded by COST Action CA21157“European Network for Innovative Woody Plant Cloning”www.cost.eusupported by COST(European Cooperation in Science and Technology)www.cost.eu。
文摘Reforestation initiatives are often limited by insufficient seeds,a problem exacerbated by natural variability in tree flowering and seed production and climate change and other environmental challenges.Innovative and adaptive solutions such as in vitro propagation are thus needed.Tissue culture can provide high-quality propagation material for tree conservation and mass propagation,but faces technical,economic,regulatory,and social barriers.Obstacles related to the academia-industry interface and to stakeholder concerns are discussed and actions suggested to overcome these barriers to realize the full potential of tree micropropagation.These include refining techniques to improve efficiency and reduce costs;establishing collaborations among researchers,industry,and foresters;and reducing points of contention and misinformation regarding genetic diversity and public perception.International collaborative initiatives,exemplified by the EU COST Action CA21157 COPYTREE,are elementary for achieving these goals.
