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Understory seedlings of Quercus mongolica survive by phenological escape

Forest Ecosystems 2024年第2期11卷 236-246页

作者： Shixiong Wu Ying Liu Lulu He Wei Zeng Qijing Liu College of forestry Beijing Forestry UniversityBeijing100083China

Understanding understory seedling regeneration mechanisms is important for the sustainable development of temperate primary forests in the context of increasingly intense climate warming *** poor regeneration of dominant tree species,however,is one of the biggest challenges it faces at the ***,the regeneration of the shade-intolerant Quercus mongolica seedling is difficult in primary forests,which contrasts with the extreme abundance of understory seedlings in secondary *** mechanism behind the interesting phenomenon is still *** study used in-situ monitoring and nursery-controlled experiment to investigate the survival rate,growth performance,as well as nonstructural carbohydrate (NSC) concentrations and pools of various organ tissues of seedlings for two consecutive years,further analyze the understory light availability and simulate the foliage carbon (C) gain in the secondary and primary *** suggested that seedlings in the secondary forest had greater biomass allocation aboveground,height and specific leaf area (SLA) in summer,which allowed the seedling to survive longer in the canopy closure *** light availability and positive C gain in early spring and late autumn are key factors affecting the growth and survival of understory seedlings in the secondary forest,whereas seedlings in the primary forest had annual negative carbon *** the growing season,the total NSC concentrations of seedlings gradually decreased,whereas those of seedlings in the secondary forest increased significantly in autumn,and were mainly stored in roots for winter consumption and the following year's summer shade period,which was verified by the nursery-controlled experiment that simulated autumn enhanced light availability improved seedling survival rate and NSC *** conclusion,our results revealed the survival trade-off strategies of Quercus mongolica seedlings and highlighted the necessity of high light availability d

关键词： Carbon gain Nonstructural carbohydrate Recruitment Trade-off Biomass allocation

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Long-term changes in radial growth of seven tree species in the mixed broadleaf-Korean pine forest in Northeast China:Are deciduous trees favored by climate change?

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Journal of forestry research 2024年第5期35卷 63-77页

作者： Xiufang Gong Danyang Yuan Liangjun Zhu Zongshan Li Xiaochun Wang National Engineering Laboratory for Applied Technology of forestry and Ecology in South China College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha 410004People’s Republic of China Center for Ecological research and Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education School of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085People’s Republic of China

The role of the temperate mixed broadleaf-Korean pine forest(BKF)in global biogeochemical cycles will depend on how the tree species community responds to climate;however,species-specific responses and vulner-abilities of common trees in BKF to extreme climates are poorly *** we used dendrochronological meth-ods to assess radial growth of seven main tree species(Pinus koraiensis,Picea jezoensis,Abies nephrolepis,Fraxinus mandshurica,Phellodendron amurense,Quercus mongolica,and Ulmus davidiana)in an old-growth BKF in response to climate changes in the Xiaoxing’an Mountains and to improve predictions of changes in the tree species *** in most months and winter precipita-tion significantly negatively affected growth of *** and ***,but positively impacted growth of *** and the broadleaf species,especially ***-rica and *** and relative humidity in June significantly positively impacted the growth of most tree *** positive effect of the temperature during the previous non-growing season(PNG)on growth of *** and *** strengthened significantly with rapid warming around 1981,while the impact of PNG temperature on the growth of *** and *** changed from significantly negative to weakly negative or positive at this *** negative response of radial growth of *** and *** to precipitation during the growing season gradually weakened,and the negative response to PNG precipitation was *** the studied species,*** was the most resistant to drought,and *** recovered the best after extreme *** davidiana,*** and *** were more resistant to extreme cold than the other *** warming generally exacerbated the opposite growth patterns of conifer(decline)and broadleaf(increase)*** broadleaf tree species in the old-growth BKF probably will gradually become dominan

关键词： Tree rings Extreme climate Resistance and recovery Broad-leaved and Korean pine mixed forest

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Root overlap and allocation of above- and belowground growth of European beech in pure and mixed stands of Douglas fir and Norway spruce

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Forest Ecosystems 2024年第5期11卷 591-602页

作者： Amani S.Lwila Christian Ammer Oliver Gailing Ludger Leinemann Martina Mun Department of Silviculture&Forest Ecology of the temperate Zones University of GöttingenBüsgenweg 137077GöttingenGermany Center for Biodiversity and Sustainable Land-Use University of GöttingenBüsgenweg 137077GöttingenGermany Department of Forest Genetics and Forest Tree Breeding Faculty of Forest Sciences and Forest EcologyUniversity of GöttingenBüsgenweg 237077GöttingenGermany forestry research and Competence centre Gotha Jägerstraße 1D-99867Germany

Site conditions and species identity have a combined effect on fine root growth of trees in pure and mixed ***,mechanisms that may contribute to this effect are rarely studied,even though they are essential to assess the potential of species to cope with climate *** study examined fine root overlap and the linkage between fine root and stem growth of European beech(Fagus sylvatica)growing in pure and mixed stands with Douglas fir(Pseudotsuga menziesii)or Norway spruce(Picea abies)at two different study sites in northwestern *** study sites represented substantially different soil and climate *** each site,three stands,and at each stand,three pairs of trees were *** the pure beech stand,the pairs consisted of two beech trees,while in the mixed stands each pair was composed of a beech tree and a *** each pair,three evenly spaced soil cores were taken monthly throughout the growing *** the pure beech stands,microsatellite markers were used to assign the fine roots to individual *** in stem diameter of beech were quantified and then upscaled to aboveground wood productivity with automatic high-resolution circumference *** found that fine root overlap between neighboring trees varied independently of the distance between the paired trees or the stand types(pure versus mixed stands),indicating that there was no territorial *** wood productivity(wood NPP)and fine root productivity(root NPP)showed similar unimodal seasonal patterns,peaking in ***,this pattern was more distinct for root NPP,and root NPP started earlier and lasted longer than wood *** influence of site conditions on the variation in wood and root NPP of beech was stronger than that of stand *** NPP was,as expected,higher at the richer site than at the poorer *** contrast,root NPP was higher at the poorer than at the richer *** concluded that beech can respond to limited resources

关键词： Fine root growth Stem growth Trade-off Cost-benefit ratio Belowground territoriality Conspecific neighbors Heterospecific neighbors

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Terrain or climate factor dominates vegetation resilience?Evidence from three national parks across different climatic zones in China

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Forest Ecosystems 2024年第4期11卷 526-542页

作者： Shuang Liu Lingxin Wu Shiyong Zhen Qinxian Lin Xisheng Hu Jian Li College of Transportation and Civil Engineering Fujian Agriculture and Forestry UniversityFuzhou 350002China College of JunCao Science and Ecology Fujian Agriculture and Forestry UniversityFuzhou 350002China College of forestry Fujian Agriculture and Forestry UniversityFuzhou 350002China

Vegetation resilience(VR),providing an objective measure of ecosystem health,has received considerable attention,however,there is still limited understanding of whether the dominant factors differ across different climate *** took the three national parks(Hainan Tropical Rainforest National Park,HTR;Wuyishan National Park,WYS;and Northeast Tiger and Leopard National Park,NTL)of China with less human interference as cases,which are distributed in different climatic zones,including tropical,subtropical and temperate monsoon climates,***,we employed the probabilistic decay method to explore the spatio-temporal changes in the VR and their natural driving patterns using Geographically Weighted Regression(GWR)model as *** results revealed that:(1)from 2000 to 2020,the Normalized Difference Vegetation Index(NDVI)of the three national parks fluctuated between 0.800 and 0.960,exhibiting an overall upward trend,with the mean NDVI of NTL(0.923)>HTR(0.899)>WYS(0.823);(2)the positive trend decay time of vegetation exceeded that of negative trend,indicating vegetation gradual recovery of the three national parks since 2012;(3)the VR of HTR was primarily influenced by elevation,aspect,average annual temperature change(AATC),and average annual precipitation change(AAPC);the WYS'VR was mainly affected by elevation,average annual precipitation(AAP),and AAPC;while the terrain factors(elevation and slope)were the main driving factors of VR in NTL;(4)among the main factors influencing the VR changes,the AAPC had the highest proportion in HTR(66.7%),and the AAP occupied the largest area proportion in WYS(80.4%).While in NTL,elevation served as the main driving factor for the VR,encompassing 64.2%of its ***,our findings indicated that precipitation factors were the main driving force for the VR changes in HTR and WYS national parks,while elevation was the main factors that drove the VR in *** research has promoted a deeper understanding of the dri

关键词： National parks Vegetation resilience NDVI Probabilistic decay model Driving factors

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Effects of Different Light Qualities on the Growth Characteristics of Populus trinervis

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1043-1056页

作者： Jiaqi Li Zhensheng Qiao Dan Zong Chengzhong He Key Laboratory for Forest Genetics and Tree Improvement and Propagation in Universities of Yunnan Province Southwest Forestry UniversityKunmingChina Key Laboratory of Biodiversity Conservation in Southwest China State Forestry AdministrationSouthwest Forestry UniversityKunmingChina Key Laboratory for forestry Resources Conservation and Utilization in the Southwest Mountains of China Ministry of EducationSouthwest Forestry UniversityKunmingChina

Populus trinervis is native to China and plays an irreplaceable role in maintaining the ecological balance of boreal and temperate *** mainly grows in high-altitude *** present,there are limited studies on the response of *** to different light qualities,so it is necessary to investigate the photosynthetic physiological changes of *** in different light *** our study,*** was grown for 8 months under light filtered by three different colored *** three treatments were blue film,green film,and white plastic *** effects of blue(B),green(G),and white(W)light on photosynthetic pigment content,absolute growth,photosynthetic parameters,soluble sugar content,and chlorophyll fluorescence parameters were studied,*** to the Wtreatment,the chlorophyll a and b,carotenoids,total chlorophyll content(a+b),absolute growth of seedling height,net photosynthetic rate(PN),water use efficiency(WUE),total soluble sugars,sucrose,and nonphotochemical quenching(NPQ)of *** were significantly increased under B ***,chlorophyll a and b,carotenoids,total chlorophyll(a+b),transpiration rate(Tr),intercellular CO_(2) concentration(Ci),stomatal conductance(gs),absolute growth of seedling height and leaf length,reducing sugar,total soluble sugar content,and NPQ were significantly increased under G *** results showed that the absolute growth and chlorophyll content of *** were increased under B light,while the sugar and photosynthetic parameters were increased under G *** studies may look into how B light impacts absolute growth and promotional mechanisms,as well as how G light affects the accumulation of sugar levels.

关键词： Blue light green light white light photosynthetic pigment soluble sugar

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Degree of shade tolerance shapes seasonality of chlorophyll, nitrogen and phosphorus levels of trees and herbs in a temperate deciduous forest

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Journal of forestry research 2024年第4期35卷 60-72页

作者： Jiajia Zeng Fan Liu Yuan Zhu Jiayi Li Ying Ruan Xiankui Quan Chuankuan Wang Xingchang Wang Aulin College Northeast Forestry UniversityHarbin 150040People’s Republic of China Center for Ecological research Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021People’s Republic of China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China

Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf ***,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly *** this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous *** role of shade tolerance in shaping the seasonal variation and vertical differentiation was *** the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance *** a:b ratios gradually decreased with increasing shade *** N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf *** the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade ***,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the *** variations in N:P ratios suggest changes in N or P *** findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.

关键词： Leaf traits Leaf nutrients Seasonal variations Chlorophyll Nitrogen Phosphorus Shade tolerance Canopy layers

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Assessing forest cover changes and fragmentation in the Himalayan temperate region: implications for forest conservation and management

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Journal of forestry research 2024年第4期35卷 128-141页

作者： Kaleem Mehmood Shoaib Ahmad Anees Akhtar Rehman Aqil Tariq Qijing Liu Sultan Muhammad Fazli Rabbi Shao’an Pan Wesam Atef Hatamleh College of forestry Beijing Forestry UniversityBeijing 100083People’s Republic of China Institute of Agriculture Sciences and forestry University of SwatSwatPakistan Department of forestry The University of AgricultureDera Ismail Khan 29050Pakistan Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing 100083People’s Republic of China Beijing Key Laboratory of Precision forestry Forestry CollegeBeijing Forestry UniversityBeijing 100083People’s Republic of China School of Environmental Studies China University of GeosciencesWuhan 430074People’s Republic of China Department of Wildlife Fisheries and AquacultureCollege of Forest ResourcesMississippi State UniversityStarkvilleMS 39762‑9690USA School of Management Tianjin University of CommerceTianjin 300134People’s Republic of China Department of Computer Science College of Computer and Information SciencesKing Saud UniversityP.O.Box 5117811543 RiyadhSaudi Arabia

This study comprehensively assessed long-term vegetation changes and forest fragmentation dynamics in the Himalayan temperate region of Pakistan from 1989 to *** satellite images,including Landsat-5 TM and Landsat-8 Operational Land Imager(OLI),were chosen for subsequent assessments in October 1989,2001,2011 and *** classified maps of 1989,2001,2011 and 2019 were created using the maximum likelihood ***-classification comparison showed an overall accuracy of 82.5%and a Kappa coefficient of 0.79 for the 2019 *** revealed a drastic decrease in closed-canopy and open-canopy forests by 117.4 and 271.6 km^(2),respectively,and an increase in agriculture/farm cultivation by 1512.8 km^(2).The two-way ANOVA test showed statistically significant differences in the area of various cover *** fragmentation was evaluated using the Landscape Fragmentation Tool(LFT v2.0)between 1989 and *** large forest core(>2.00 km^(2))decreased from 149.4 to 296.7 km^(2),and a similar pattern was observed in medium forest core(1.00-2.00 km^(2))*** the contrary,the small core(<1.00 km^(2))forest increased from 124.8 to 145.3 km^(2) in *** perforation area increased by 296.9 km^(2),and the edge effect decreased from 458.9 to 431.7 km^(2).The frequency of patches also increased by 119.1 km^(2).The closed and open canopy classes showed a decreasing trend with an annual rate of 0.58%and 1.35%,*** broad implications of these findings can be seen in the studied region as well as other global ecological *** serve as an imperative baseline for afforestation and reforestation operations,highlighting the urgent need for efficient management,conservation,and restoration *** on these findings,sustainable land-use policies may be put into place that support local livelihoods,protect ecosystem services,and conserve biodiversity.

关键词： Natural catastrophes Landsat Change detection Forest fragmentation Landscape fragmentation tool(LFT) Afforestation Reforestation

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Spotting ignition of larch(Larix gmelinii)fuel bed by different firebrands

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Journal of forestry research 2022年第1期33卷 171-181页

作者： Guang Yang Jibin Ning Lifu Shu Jili Zhang Hongzhou Yu Xueying Di School of forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Forest Protection Research Institute of Forest EcologyEnvironment and ProtectionChinese Academy of ForestryState Forestry AdministrationBeijing 100091People’s Republic of China research centre of cold temperate forestry Chinese Academy of ForestryHarbin 150086People’s Republic of China

Spot fire increase the difficulty of fire-fighting and threaten public safety,and therefore it is important to study ignition probabilities of fuel bed by different firebrands,in order to understand ignition mechanisms and analyze the formation of spot *** will provide an important basis for further study to improve the fire-fighting efficiency and reduce *** this study,the ignition probabilities of larch(Larix gmelinii)fuel beds with different moisture levels and packing ratios by diffreent firebrands,including cones and twigs of different sizes,was *** experiments were conducted at different wind speeds generated by *** results show that,regardless of moisture content and packing ratio,ignition probability is zero when there is no *** moisture content and wind speed significantly infuence ignition probability,while packing ratio has almost no *** maximum moisture content at which firebrand ignition occurred was 50%,and ignition probability increased with wind speed and decreased with moisture *** have the highest ignition probability,followed by large twigs and by small *** probability is also affected by firebrand shapes and sizes that determine their potential heat and contact area to the fuel *** empirical models were established to link ignition probability with fuel properties and wind *** study will help clarify the mechanism of spot ignition and reduce corresponding losses.

关键词： Firebrands Wind speed Moisture content Packing ratio Logistic model Larix gmelinii

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Belowground Bud Bank Is Insensitive to Short-Term Nutrient Addition in the Meadow Steppe of Inner Mongolia

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1129-1141页

作者： Jin Tao Jiatai Tian Dongmei Li Jinlei Zhu Qun Ma Zhiming Zhang Jungang Chen Yipeng Liu Jianqiang Qian College of forestry Henan Agricultural UniversityZhengzhou450002China Institute of Ecological Conservation and Restoration Chinese Academy of ForestryBeijing100093China Institute of Applied Ecology Chinese Academy of SciencesShenyang110164China Institute of Botany Chinese Academy of SciencesBeijing100093China Liaoning Metallurgical Geological Exploration research Institute Co. Anshan114038China

Human activities and industrialization have signiﬁcantly increased soil nutrients,such as nitrogen(N)and phos-phorus(P),profoundly impacting the composition and structure of plant community,as well as the ecosystem functions,especially in nutrient-limited ***,as the key propagule pool of perennial grasslands,how belowground bud bank and its relationship with aboveground vegetation respond to short-term changes in soil nutrients was still *** this study,we conducted a short-term(2021–2022)soil fertilization experiment with N addition(10 g N m^(-2) yr^(-1))and P addition(5 g N m^(-2) yr^(-1))in the meadow steppe of Inner Mongolia,China,to explore the responses of belowground bud bank,aboveground shoot population and their relationships(represented by the ratio of bud to shoot density-meristem limitation index(MLI))for the whole community and three plant functional groups(perennial rhizomatous grasses-PR,perennial bunchgrasses-PB,and perennial forbs-PF)to nutrient *** short-term nutrient addition had no signiﬁcant inﬂuences on belowground bud density,aboveground shoot density,and MLI of the whole plant *** functional groups showed different responses to soil ***ﬁcally,N addition signiﬁcantly increased the bud density and shoot density of PR,especially in combination with P addition.N addition reduced the shoot density of PF but had no inﬂuence on its bud density and *** addition had signiﬁcant effects on the three indicators of *** study indicates that the belowground bud bank and its relationship with aboveground vegetation in temperate meadow steppe are insensitive to short-term soil fertilization,but plant functional groups exhibit speciﬁc responses in terms of population regeneration,which implies that plant community composition and ecosystem functions will be changed under the ongoing global change.

关键词： Clonal trait population regeneration community dynamics soil resource availability nitrogen addition

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Deadwood position matters:Diversity and biomass of saproxylic beetles in a temperate beech forest

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Forest Ecosystems 2024年第1期11卷 120-130页

作者： Vaclav Zumr Oto Nakladal Josef Gallo JiríRemes Faculty of forestry and Wood Sciences Czech University of Life Sciences PragueKamýck a 129Praha 6-Suchdol16500Czech Republic

Deadwood plays a key role for biodiversity in forests.A significant number of beetles from this group are currently listed as endangered in the Red *** addition to other management recommendations,there have been recent efforts to enrich stands with dead wood to promote *** important parameter for forestry enterprises is the optimization of these *** study investigated the abundance,species richness,gamma diversity,conservation value and biomass of saproxylic beetles in natural forests using window traps.A total of 89traps were used for saproxylic beetle monitoring,of which 29 were placed on lying logs,30 on snags and 30 as controls in forest stand space.A total of 35,011 beetles were recorded in 564 species(61 families).Notably,20,515 of these belong to saproxylic beetles(59%)in 311 species(55%),with 62 classified as Red-List species(20%).In the group of'all saproxylic beetles',the results indicate that a diversity and y diversity(q=0)remain consistent across various deadwood types,whileβdiversity showed significant *** differences were found in the Red-List species group,where a diversity and y diversity differed,with higher values observed in *** based total species richness of site was estimated to be 391 species,including 74 Red-Listed *** the sample coverage of the studied stand categories showed that all saproxylic species exhibit a pronounced preference for inhabiting areas featuring lying ***,Red-List species mainly inhabit snags,withβdiversity being more similar to snags and forest stand ***,both the conservation value(weighted average by conservation status)and beetle biomass are significantly highest in snags,whereas stand space shows the lowest values across all measured saproxylic beetle ***,the use of traps set on the poles in forest stand space resulted in an underestimation of the actual stand richness by 20%-25%.Our results support th

关键词： Snags Coleoptera Fagus sylvatica Unmanaged forests Red-list Coarse woody debris

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