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美国Spruce Pine地区花岗伟晶岩高纯石英优质原料的矿物材料学特征 被引量:8
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作者 王哲皓 奚旺 汪灵 《矿物岩石》 北大核心 2025年第1期106-116,共11页
美国北卡罗来纳州Spruce Pine地区的花岗伟晶岩石英,是迄今为止世界上独一无二的高纯石英优质原料。为了提升对这一特殊的石英矿产资源的认识,为我国同类型高纯石英原料的找矿与评价提供科学依据,本次研究以该地区花岗伟晶岩石英及其4N... 美国北卡罗来纳州Spruce Pine地区的花岗伟晶岩石英,是迄今为止世界上独一无二的高纯石英优质原料。为了提升对这一特殊的石英矿产资源的认识,为我国同类型高纯石英原料的找矿与评价提供科学依据,本次研究以该地区花岗伟晶岩石英及其4N8高纯石英高端产品为研究对象,采用电感耦合等离子体发射光谱仪、X射线荧光光谱仪、X射线衍射仪、扫描电镜和偏光显微镜等现代分析测试技术,详细研究了该矿典型样品的化学成分与痕量元素特征、矿物组成、显微结构、矿物包裹体和气液包裹体等矿物材料学特征,结果表明:(1)花岗伟晶岩样品的化学成分(w_(B)/%)为SiO_(2)70.89%,Al_(2)O_(3)14.97%,K2O 7.28%,Na_(2)O 3.21%,矿物组合(w_(B)/%)为微斜长石38%,钠长石27%,石英24%,白云母7%。(2)石英呈浅烟灰色,结晶良好,有粒状石英和蠕虫状石英两种结构类型,其中粒状石英是高纯石英的主要原料。(3)石英中矿物包裹体主要是白云母和极少量细小的透明矿物包裹体,大小分别为0.1~0.5 mm和<10μm,气液包裹体主要为次生包裹体,大小为1~20μm,数量较少,液相中的阳离子成分以Na^(+),K^(+),Ca^(2+)为主。(4)由于具有良好的杂质提纯可选性,石英中的晶格间隙杂质、矿物包裹体和气液包裹体等主要杂质可被有效去除。(5)以该矿为原料加工的4N8高纯石英,其杂质主要为Al和Ti等晶格置换杂质,Al含量为12×10^(-6)~15×10^(-6),Ti含量在±1.2×10^(-6),其它杂质元素含量均<1×10^(-6)。 展开更多
关键词 高纯石英 花岗伟晶岩 Spruce pine 石英 矿物材料
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美国Spruce Pine白岗岩长石和云母矿物学特征研究:对高纯石英原料矿的指示意义 被引量:1
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作者 胡欢 王汝成 +2 位作者 谢磊 徐渴鑫 董少春 《岩石学报》 北大核心 2025年第10期3453-3468,共16页
高纯石英是半导体、光伏、光纤通信等高科技产业的关键战略材料,其优质原料主要来自花岗伟晶岩和脉石英。美国北卡罗来纳州Spruce Pine地区白岗岩-伟晶岩矿床是全球最著名的高纯石英来源之一,本次研究以Spruce Pine白岗岩为对象,利用矿... 高纯石英是半导体、光伏、光纤通信等高科技产业的关键战略材料,其优质原料主要来自花岗伟晶岩和脉石英。美国北卡罗来纳州Spruce Pine地区白岗岩-伟晶岩矿床是全球最著名的高纯石英来源之一,本次研究以Spruce Pine白岗岩为对象,利用矿物自动鉴别系统AMICS、电子探针和LA-ICP-MS开展了岩相学、全岩地球化学和矿物原位主微量元素成分分析,得到以下认识:(1) Spruce Pine白岗岩主要矿物为透长石、奥长石-钠长石、白云母(成分均一、贫Li低F)和石英。副矿物很少,主要有石榴石、绿帘石和锆石等;(2)全岩地球化学表明,美国Spruce Pine白岗岩为极低TiO_(2)含量、低挥发组分、高Sr、Ba和Nb/Ta(>5)、低Rb和Rb/Sr(<10),中等Eu负异常的过铝质花岗岩(A/CNK=1.10~1.11)。钾长石和白云母微量元素具有高Ba、Sr和K/Rb(钾长石>236,云母>96),低Li、Rb、Cs特征。美国Spruce Pine白岗岩为极低TiO_(2)、中等结晶分异且无显著流体作用的白云母花岗岩;(3)对比世界典型稀有金属花岗岩/伟晶岩,高纯石英矿床花岗岩/伟晶岩为经历中等-高度结晶分异作用、弱流体作用、低TiO_(2)含量、准铝-过铝质的贫稀有金属花岗岩/伟晶岩,而岩石地球化学参数Rb/Sr(=10)、Nb/Ta(=5)、Eu负异常以及云母F含量、钾长石和云母K/Rb比值是区分高纯石英花岗岩/伟晶岩和稀有金属花岗岩/伟晶岩较好的地球化学指标。总之,低TiO_(2)、中等-高结晶分异且弱流体作用的贫矿白云母花岗岩/伟晶岩为我国寻找高纯石英优质原料的潜在目标。 展开更多
关键词 Spruce pine 高纯石英 全岩地球化学 矿物化学成分
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美国Spruce Pine地区高纯石英原矿岩石变形研究 被引量:1
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作者 郭宜琳 褚杨 +1 位作者 夏冉然 薛振华 《岩石学报》 北大核心 2025年第10期3469-3489,共21页
高纯石英是半导体等高新技术发展的物质基础,但我国高端高纯石英长期依赖外国进口,高纯石英矿的缺乏制约着半导体行业的快速发展。美国北卡罗来纳州Spruce Pine地区的花岗岩及伟晶岩是世界上最为重要的高纯石英原料来源。研究该地区的... 高纯石英是半导体等高新技术发展的物质基础,但我国高端高纯石英长期依赖外国进口,高纯石英矿的缺乏制约着半导体行业的快速发展。美国北卡罗来纳州Spruce Pine地区的花岗岩及伟晶岩是世界上最为重要的高纯石英原料来源。研究该地区的岩石样品,可以帮助我们了解高纯石英原料的产出背景,为我国寻找高纯石英矿提供理论指导。本文以采自Spruce Pine高纯石英矿的两件岩浆岩样品为研究对象,通过显微构造观察和石英EBSD组构分析,揭示了样品的岩相学和组构特征,并计算了变形条件,进而探讨了该地区岩石在高纯石英产出方面的优势。研究表明,样品SP-S1为伟晶岩,样品SP-S2为白云母花岗岩,二者矿物组合类似,但变形程度差异较大。伟晶岩变形较弱,石英变形以位错蠕变和膨凸重结晶为主,含大量分布杂乱的流体包裹体,估算得出变形温度约300~400℃,变形差异应力约18.26~21.40MPa,应变速率在10^(-12.77)~10^(-10.59)s^(-1)之间。花岗岩变形较强,具明显定向组构,石英发生位错蠕变和颗粒边界迁移重结晶,流体包裹体含量相对较少但垂直或平行石英长轴产出,估算得出变形温度约500~600℃,变形差异应力约18.63~21.68MPa,应变速率在10^(-11.79)~10^(-10.50)s^(-1)之间。该地区岩石能够作为高纯石英原料,可能得益于高分异的岩浆演化过程使得石英原始纯度较高,晶内塑性变形(位错蠕变、动态重结晶)对石英进一步净化,以及流体包裹体提供了容纳杂质的空间并使杂质易于剔除;同时中-高温度、低差异应力等变形条件可能抑制了杂质重新进入石英颗粒。通过对比不同高纯石英矿区的构造背景和变形条件,我们提出多期次造山带的核部是高纯石英产出的有利部位,中部地壳层次、高绿片岩相-低角闪岩相下的变形有利于石英提纯,并据此推测喜马拉雅造山带的淡色花岗岩具有高纯石英成矿潜力。 展开更多
关键词 高纯石英 Spruce pine 变形条件 位错蠕变 动态重结晶
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Properties of ions may explain elemental stoichiometry in late-and early-wood:a case study in Scots pine tree rings
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作者 Vladimir L.Gavrikov Ruslan A.Sharafutdinov +1 位作者 Alexey I.Fertikov Eugene A.Vaganov 《Journal of Forestry Research》 2025年第1期493-504,共12页
Understanding why elements are distributed in tree xylem in a particular way is a significant challenge in dendrochemistry.This study explored a hypothesis that metal elements in the xylem interact due to differences ... Understanding why elements are distributed in tree xylem in a particular way is a significant challenge in dendrochemistry.This study explored a hypothesis that metal elements in the xylem interact due to differences in physical properties such as ionic radius and ionization potential.Scots pine in an even-aged stand established during the early 1970s in eastern Siberia was the study species.Increment cores were taken from the north and south sides of trees and scanned with an X-ray fluorescent multi scanner.With the help of X-ray scanning,the following elements were analyzed:aluminum(Al),potassium(K),calcium(Ca),titanium(Ti),manganese(Mn),iron(Fe),copper(Cu),strontium(Sr)and zinc(Zn).Scanning data on the elements were split into early-wood and late-wood data for each year of growth.The following ratios were analyzed:Ca/Sr,Fe/Ca,Fe/Sr,Al/Cu,Al/Zn,Ti/Mn,and Mn/K.Among these,ones having a consistent pattern across tree rings,the ratios show a more or less dependable relationship:that an element shows a larger decrease(relative another element)that has a larger ionic radius and lower ionization potential.Hypothetically,this may be due to the advantage of an ion with smaller ionic radius and higher ionization potential under a deficit of accommodation centers in organic molecules.An experiment approach should be applied to clarify the relationships. 展开更多
关键词 Dendrochemistry Tree rings Early-wood Late-wood Scots pine
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Control efficacy and persistence of fluopyram dust against pine wilt disease
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作者 Yajie Guo Jiayi Ma +5 位作者 Mingqing Weng Rebeca Carballar-Lejarazú Wenlong Jiao Jieqin Wu Feiping Zhang Songqing Wu 《Journal of Forestry Research》 2025年第4期205-214,共10页
The effectiveness of fluopyram suspension concentrate against pine wilt disease(PWD)is limited by spraying efficiency and water dependence.A traditional dust formulation with strong dispersibility can overcome these s... The effectiveness of fluopyram suspension concentrate against pine wilt disease(PWD)is limited by spraying efficiency and water dependence.A traditional dust formulation with strong dispersibility can overcome these shortcomings.However,its efficacy against PWD remains uncertain.This study evaluated the translocation of fluopyram dust within tree tissues,soil and water degradation,and its effective control against PWD.Nursery tests showed effective prevention;field tests showed dust absorption and translocation into pine tissues.Thirty days following application,residual concentrations in soil were low at 0.09 mg kg^(−1);no detectable residues were found in water samples.Three years after applying fluopyram,its effectiveness increased to approximately 87%.Based on this study,fluopyram had a half-life of 346 d with persistence lasting up to three years.This provides valuable insight for managing PWD through dust applications. 展开更多
关键词 pine wilt disease Fluopyram Dust formulation EFFICACY PERSISTENCE
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Growth dynamics of longleaf pine during conversion to uneven-aged stands
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作者 Ashton Shell Ajay Sharma +4 位作者 John L.Willis John Tracy Adam Polinko Santosh Ojha Jason Vogel 《Forest Ecosystems》 2025年第3期514-523,共10页
A growing recognition that uneven-aged silviculture can offer multiple benefits to forested ecosystems has encouraged some landowners in the southern region of the United States to convert even-aged pine stands into m... A growing recognition that uneven-aged silviculture can offer multiple benefits to forested ecosystems has encouraged some landowners in the southern region of the United States to convert even-aged pine stands into multi-aged stands.For shade-intolerant pines of the southern United States,however,few studies have examined residual tree growth following silvicultural treatments that convert even-aged stands to multi-aged stands.Understanding the growth response of residual trees to different kinds of stand conversion treatments is critical to stand development and sustainability,as trees must be recruited into larger size classes during the conversion process to develop the desired stand structure and maintain productivity.In this study,we utilized a replicated,long-term silvicultural experimental trial in the southeastern United States to assess the effects of two cutting treatments(dispersed"single tree cutting"that created small canopy gaps and the"patch cutting"that created 0.1-0.8ha patch openings)and an uncut control on the 14-year growth(~cutting cycle length)of residual longleaf pine(Pinus palustris Mill.)trees.We found that tree growth,measured as mean basal area increment(BAI),was significantly higher following patch cutting(mean BAI of 16.97cm^(2))compared to both the single tree cutting(13.33cm^(2))and the uncut control(12.68cm^(2))(p<0.001).In patch cutting,the size of the patch opening,the location of trees surrounding the patch opening,and the position of the tree canopy all had a significant effect on BAI.Trees surrounding patch openings of 0.4ha exhibited greater growth,with a mean BAI of 19.24cm^(2),compared to those surrounding 0.1 and 0.8ha patch openings,which had mean BAI values of 15.89 and 15.71cm^(2),respectively(p<0.001).The position of a tree around the patch opening also influenced tree growth,as residual trees more to the North,South,and East sides exhibited significantly higher mean BAI than trees on the West side of the patch openings(p<0.001).However,distance from the patch opening border did not significantly affect the mean BAI(p=0.522).In all treatments,dominant and co-dominant trees exhibited higher BAI than intermediate and overtopped trees,indicating that tree canopy position significantly influenced tree growth(p<0.001).Understanding how residual trees grow after these silvicultural treatments is crucial for thoroughly assessing their efficacy with longleaf pine.This study's findings will enhance our understanding of stand dynamics during stand conversion and help land managers anticipate the growth of longleaf pine into larger size categories after single tree and patch cuttings. 展开更多
关键词 Uneven-aged silviculture Multi-aged stands Stand conversion Group openings Hurricane disturbance Southern pine Pinus palustris Mill.
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Effects of simulating nitrogen and phosphorus deposition on soil nitrogen and enzymatic activity in Korean pine forests in northeast China
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作者 Shaoran Li Lixin Chen +1 位作者 Wenbiao Duan Yifei Li 《Journal of Forestry Research》 2025年第4期127-148,共22页
Nitrogen and phosphorus (NP) deposition can change the nutrient input of forest ecosystems. The effects of NP deposition on soil aggregate need to be analyzed to propose effective environmental management strategies. ... Nitrogen and phosphorus (NP) deposition can change the nutrient input of forest ecosystems. The effects of NP deposition on soil aggregate need to be analyzed to propose effective environmental management strategies. In this study, representative Korean pine mixed forests and Korean pine plantations in northeastern China were selected. Soil samples were sieved to obtain four different particle sizes of soil aggregates (> 2, 2–0.25, 0.25–0.053, and  < 0.053 mm). Four NP treatments were applied to simulate N and P deposition, and an indoor incubation experiment was conducted over a period of 360 d. Total nitrogen, microbial nitrogen, dissolved organic nitrogen, hydrolyzed nitrogen, NH_(4)^(+)–N, NO_(3)^(−)–N content, and extracellular enzyme activities of NAG, LAP, and AP were determined. Different fractions of N responded differently to NP addition. Lower NP addition had a greater promoting effect on aggregate N compared to higher NP addition. NAG was the main extracellular enzyme affecting N in both forest types. NP addition had a greater effect on the extracellular enzyme activities of the soil aggregates from the Korean pine plantations. These results enhance our understanding of the effects of NP addition on soil nitrogen within temperate forest ecosystems. 展开更多
关键词 Korean pine Nitrogen-phosphorus addition Soil aggregate Nitrogen fractions Extracellular enzymes
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Adaptive optimisation of the management of Korean pine plantation
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作者 Qianping Tong Xingji Jin +2 位作者 Timo Pukkala Lihu Dong Fengri Li 《Forest Ecosystems》 2025年第4期677-687,共11页
Forest management planning faces uncertainties regarding future timber prices,tree growth,and survival.Future seed production is an additional source of uncertainty in Korean pine stands managed for the joint producti... Forest management planning faces uncertainties regarding future timber prices,tree growth,and survival.Future seed production is an additional source of uncertainty in Korean pine stands managed for the joint production of timber and edible seeds.Modern forest planning uses optimisation to determine the best possible cutting schedule.Optimisation can accommodate uncertainty by using decision rules for adaptive forest management instead of optimising cutting years and intensities.In this study,we optimised two adaptive decision rules for managing Korean pine plantations for the joint production of timber and pinecones when timber prices,tree growth,and seed production are stochastic.The first rule indicated the minimum price to sell timber,i.e.,the reservation price,as a function of the mean tree diameter and stand basal area.The second adaptive rule expressed the mean tree diameter at which cutting is optimal as a function of timber price and stand basal area.Both decision rules resulted in nearly the same mean net present value when the optimised rule was applied to 100 stochastic scenarios for future timber prices,tree growth,and seed production.The net present values were over 20% higher than those for the deterministically optimised cutting schedules under the same scenarios.Therefore,the expected economic gain from switching from deterministic to adaptive stochastic optimisation was at least 20%.The cutting years of the adaptive optima were frequently later than those indicated by the deterministic optima,and optimal adaptive harvesting often involved waiting for high timber prices.The minimum price or minimum mean diameter to sell timber was higher when the income from seeds was considered in the optimisation.The cuttings were later,and the rotations were longer in the joint production of timber and pinecones than in timber production alone. 展开更多
关键词 Pinus koraiensis Reservation price pine nuts Non-wood forest products Decision rule Adaptive management
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Restoration of natural herbaceous vegetation and spatial variability of forest structure by gradual removal of Scots pine from former plantations
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作者 Remigiusz Pielech Adrian Wysocki +4 位作者 Kacper Foremnik Marek Malicki Bartłomiej Surmacz Jerzy Szwagrzyk Zbigniew Maciejewski 《Forest Ecosystems》 2025年第2期287-299,共13页
We tested the effectiveness of the gradual removal of Scots pine(Pinus sylvestris L.)in former plantations of this species in Roztocze National Park(SE Poland)to support the restoration of natural herbaceous flora and... We tested the effectiveness of the gradual removal of Scots pine(Pinus sylvestris L.)in former plantations of this species in Roztocze National Park(SE Poland)to support the restoration of natural herbaceous flora and forest structure.We compared 0.5-ha study plots subjected to selective removal of pine trees with control plots excluded from any kind of human intervention for half a century.The observed changes in forest floor vegetation in the converted plots showed naturalization towards habitat-specific species.However,differences in the spatial distribution of trees between the treatment and control plots showed no universal pattern and revealed subtle but positive shifts from regular to random or clustered patterns.The mean tree diameters were higher in plots subjected to Scots pine removal,which resulted from the vigorous growth of tree species,consistent with habitat types.We conclude that forest restoration through the removal of planted trees can support the naturalization of former Scots pine plantations in protected areas.However,the selection of an appropriate method and its intensity are of vital importance.Methods that resemble typical management practices,such as selection thinning,are not always the best approach,as they may preserve or even increase the regular distribution of trees.Therefore,for restoration purposes,we recommend testing other methods that increase spatial heterogeneity,including systematic cutting or emulating natural disturbances.In addition,low-intensity thinning may not be sufficient to support the restoration of natural forest floor vegetation and the variability in forest stand structure. 展开更多
关键词 Forest conversion Forest structure National park Pinus sylvestris Spatial patterns Scots pine Herbaceous vegetation RESTORATION
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Variation in pine growth response to site preparation methods in the Lower Coastal Plain of the southeastern US
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作者 Dehai Zhao Bronson P.Bullock +1 位作者 Stephen M.Kinane Mingliang Wang 《Forest Ecosystems》 2025年第6期1276-1283,共8页
This study evaluated the long-term growth responses of pine plantations in the Lower Coastal Plain of Florida to different site preparation(SP)treatments,including variations in bedding timing(early or late),frequency... This study evaluated the long-term growth responses of pine plantations in the Lower Coastal Plain of Florida to different site preparation(SP)treatments,including variations in bedding timing(early or late),frequency(single or double),and herbicide use(banded or broadcast pre-plant application),with or without first-year post-plant herbaceous weed control(HWC).The results showed that growth responses varied by location,primarily influenced by the effectiveness of vegetation control,especially in suppressing woody shrubs.Pre-plant herbicide treatments consistently improved growth,with broadcast applications often performing as well or better than the banded treatments.Although bedding timing and frequency influenced growth at some sites,their effects were inconsistent.Superior growth was observed in treatments combining early bedding with pre-plant herbicide,even without HWC,highlighting the critical role of effective vegetation management in enhancing the productivity of pine plantations. 展开更多
关键词 pine plantation Site preparation(SP) Competing vegetation control BEDDING HERBICIDES
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Minimum area of primitive broad-leaved Korean pine forest community based on biomass
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作者 Huibin Yang Qingxi Guo 《Journal of Forestry Research》 2025年第1期347-357,共11页
Based on the survey data of nine primitive broad-leaved Korean pine forest plots ranging from 1 to 10.4 ha in Heilongjiang Province,this study used the moving window method and GIS technology to analyze the variation ... Based on the survey data of nine primitive broad-leaved Korean pine forest plots ranging from 1 to 10.4 ha in Heilongjiang Province,this study used the moving window method and GIS technology to analyze the variation characteristics of the spatial distribution pattern of forest biomass in each plot.We explored the minimum area that can reflect the structural and functional characteristics of the primitive broad-leaved Korean pine forest,and used computer simulation random sampling method to verify the accuracy of the minimum area.The results showed that:(1)Through the analysis of the spatial distribution raster map of biomass deviation in the plots at various scales of 10−100 m,there is a minimum area(0.64 ha)for the critical range of biomass density variation in the primitive broad-leaved Korean pine forest.This minimum area based on biomass density can indirectly reflect the comprehensive characteristics of productivity level per unit area,structure,function,and environmental quality of the primitive broad-leaved Korean pine forest community.(2)Using computer simulation random sampling,it was found that only by sampling in a specific plot larger than or equal to the minimum area can equivalent or similar results be achieved as random sampling within the plot,indicating that the minimum area determined by the moving window method is accurate.(3)The minimum area determined in this paper is an excellent indicator reflecting the complexity of community structure,which can be used for comparing changes in community structure and function before and after external disturbances,and has a good evaluation effect.This minimum area can also be used as a basis for scientific and reasonable setting of plot size in the investigation and monitoring work of broad-leaved Korean pine forests in this region,thereby achieving the goals of improving work efficiency and saving work costs. 展开更多
关键词 Minimum area of community Community structure BIOMASS Spatial heterogeneity Broad-leaved Korean pine forest
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Saprotrophic fungal community responses to nitrogen additions in a Korean pine plantation:insights from using the mycoindicator
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作者 Ruotong Wu Huanhuan Zhang +2 位作者 Mengmeng Zhang Guangze Jin Fuqiang Song 《Journal of Forestry Research》 2025年第3期29-44,共16页
Human activities contribute to elevated nitrogen input in terrestrial ecosystems,influencing the composition of soil nutrients and microbial diversity in forest ecosystems.In this study,we built four addition treatmen... Human activities contribute to elevated nitrogen input in terrestrial ecosystems,influencing the composition of soil nutrients and microbial diversity in forest ecosystems.In this study,we built four addition treatments(0,20,40,and 80 kg ha^(−1)a^(−1)N for 6 a)at a Korean pine plantation of different soil horizons(organic(O)horizon,ranging from 0 to 10 cm,and organomineral(A)horizon,extending from 10 to 20 cm)to evaluate responses of the structure of saprophytic fungal communities.Here,80 kg ha^(−1)a^(−1)N treatment significantly decreased the community richness in soil A horizon with the Chao1 index decreasing by 12.68%.Nitrogen addition induced changes in the composition of saprophytic fungi community between the different soil horizons.The co-occurrence network and its associated topological structure were utilized to identify mycoindicators for specific fungi to both soil horizons and nitrogen addition levels.In soil O horizon,the mycoindicators included Penicillium,Trichoderma,Aspergillus,and Pseudeurotium across control,low,medium,and high nitrogen treatments.In soil A horizon,Geomyces,Cladophialophora,Penicillium,and Pseudeurotium were identified as mycoindicators.Structural equation modeling determined NH_(4)^(+)-N as the key factor driving changes in saprotrophic fungal communities.Our study aimed to screen mycoindicators that can respond to the increasing global nitrogen deposition and to assess the roles of these mycoindicators in the saprophytic fun-gal community structure within Korean pine plantations in northeast China. 展开更多
关键词 Korean pine plantations Soil fungal community structure Saprophytic fungal Mycoindicator
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Patterns of biomass,carbon,and nitrogen storage distribution dynamics after the invasion of pine forests by Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae) in the three Gorges Reservoir Region 被引量:2
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作者 Ruihe Gao Youqing Luo +2 位作者 Zhuang Wang Hanjun Yu Juan Shi 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期453-464,共12页
Masson pine stands infected by Pine wilt disease(PWD) in the Three Gorges Reservoir Region of central China were surveyed to quantify the immediate responses and subsequent trajectories of biomass,carbon(C),and nitrog... Masson pine stands infected by Pine wilt disease(PWD) in the Three Gorges Reservoir Region of central China were surveyed to quantify the immediate responses and subsequent trajectories of biomass,carbon(C),and nitrogen(N) in stand-level major ecosystem compartments.The biomasses of above-and belowground tree components,as well as of the understory,forest floor,and mineral soil(0–40 cm),were determined within each stand.C and N storage were also estimated for each ecosystem compartment.Overstory biomass decreased steadily with the extent of PWD infection.Understory biomass ranged from1.97 to 4.16 Mg ha,and the observed value for forest floor biomass was 12.89–22.59 Mg ha.The highest mean C and N concentrations were found in the stem bark and needles of Masson pine,respectively,while the lowest were found in the semi-to fully decomposed layer of the forest floor and stem wood of Masson pine,respectively.The C and N storage of aboveground trees,tree roots,and the aboveground ecosystem decreased with the extent ofPWD infection.However,the C and N contents of the understory,forest floor,and total mineral soil initially declined after PWD infection before recovering over the following several years.Those result concluded that the biomass,C,and N storage of different forest ecosystem compartments have experienced certain variations following the PWD epidemic.This is vital to understand the shifts in stand-level C and N allocation in PWD-damaged forest stands,as well as for predicting the responses of regional and global C and N cycling. 展开更多
关键词 CARBON Insect outbreak Masson pine Nitrogen pine sawyer beetle pine wilt disease
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美国Spruce Pine与新疆阿尔泰地区高纯石英伟晶岩的对比研究 被引量:49
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作者 张晔 陈培荣 《高校地质学报》 CAS CSCD 北大核心 2010年第4期426-435,共10页
对美国北卡罗来纳州Spruce Pine地区白岗岩/伟晶岩和新疆阿尔泰白云母花岗岩/伟晶岩进行了对比研究。这两个地区的伟晶岩可能是过铝质花岗岩浆通过熔体-蒸汽分异作用的产物。美国产高纯石英的伟晶岩发育在片岩、片麻岩的背景之上,主要... 对美国北卡罗来纳州Spruce Pine地区白岗岩/伟晶岩和新疆阿尔泰白云母花岗岩/伟晶岩进行了对比研究。这两个地区的伟晶岩可能是过铝质花岗岩浆通过熔体-蒸汽分异作用的产物。美国产高纯石英的伟晶岩发育在片岩、片麻岩的背景之上,主要造岩矿物中富含斜长石,Na大于K,大离子亲石元素Sr和Ba含量高,高场强元素和稀土元素含量低,Eu正异常,石英中杂质元素含量低。这些特征可作为高纯石英伟晶岩的判别标志。我国阿尔泰地区的伟晶岩脉十分发育,所研究的样品中,有些样品已经具有这些特点,阿尔泰伟晶岩区具有产高纯石英的成矿前景。 展开更多
关键词 伟晶岩 高纯石英 SPRUCE pine 阿尔泰
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Cloning of cDNA Fragment of Chitinase Gene from the Mycoparasite Trichoderma atroviride on Armandii Pine Blister Rust 被引量:5
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作者 马长乐 李靖 +1 位作者 陈玉惠 刘小烛 《Agricultural Science & Technology》 CAS 2008年第6期47-50,67,共5页
[Objective] The aim of this study was to isolate chitinase gene from Trichoderma atroviride strain SS003. [Method] With the aeciospore wall of armandii pine blister rust as inducer, chitinase gene was induced to expre... [Objective] The aim of this study was to isolate chitinase gene from Trichoderma atroviride strain SS003. [Method] With the aeciospore wall of armandii pine blister rust as inducer, chitinase gene was induced to express in Trichoderma atroviride cells. The cDNA fragment of chitinase gene was cloned by RT-PCR approach. [Result] The activity of chitinase induced reached 40.17 μg/10 min; and the specific fragment amplified was 834 bp in length and proved to be the fragment of chitinase gene by sequencing and sequence analysis. [Conclusion] The result showed the feasibility of isolating the full length of chitinase gene and its transformation, and further producing chitinase. 展开更多
关键词 Armandii pine BLISTER RUST TRICHODERMA atroviride MYCOPARASITE Induction CHITINASE
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Genetic variations of wood properties and growth characters of Ko-rean pines from different provenances 被引量:5
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作者 王慧梅 夏德安 +1 位作者 王文杰 杨书文 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期277-280,337,共4页
Totally 26 provenance stands of 17-year-old Korean pine were selected for investigating wood properties and growth characters in Mao抏rshan Experimental Forest Farm of Northeast Forestry University in 1999. The anatom... Totally 26 provenance stands of 17-year-old Korean pine were selected for investigating wood properties and growth characters in Mao抏rshan Experimental Forest Farm of Northeast Forestry University in 1999. The anatomical property indexes, including tracheid length, tracheid diameter and wall-indiameter ratio, and the physical property indexes, such as growth ring width, late wood percentage and growth ring density, were measured for wood properties. Growth character indexes, including tree height and diameter at breast height, were also measured. The analytical results showed that there exited obviously dif-ference in wood property indexes between different provenances, which is suggested that wood properties are controlled by their genetic differences. The growth character indexes of Korean pines presented significant difference and they might also be controlled by their genetic differences. Most parameters of wood properties mainly varied in the direction of longitude, but the parameters of growth characters varied in the direction of latitude. 展开更多
关键词 Korean pine Provenance trial Wood properties Geographical variation Genetic variation
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Influence of canopy on precipitation and its nutrient elements in broadleaved/Korean pine forest on the northern slope of Changbai Mountain 被引量:3
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作者 肖以华 代力民 +3 位作者 牛德奎 佟富春 陈高 邓红兵 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期201-204,251,共4页
The precipitation distribution quantity of canopy in broadleaved/Korean pine forest was measured during the growing season (Jun.–Sept.) in 2001 in the Changbai Mountain, Jilin Province, P. R. China. Results indicated... The precipitation distribution quantity of canopy in broadleaved/Korean pine forest was measured during the growing season (Jun.–Sept.) in 2001 in the Changbai Mountain, Jilin Province, P. R. China. Results indicated that the amounts of stemflow, throughfall, and interception were 37.39, 322.12 and 109.69 mm, accounting for 7.97%, 68.65% and 23.38% of the total rainfall, respectively. The rate of stemflow was higher in Jul. and Aug. than other months. The rate of throughfall dropped off from Jun. to Sept., however, rate of interception changed contrarily from 19.43% to 31.02% during the growing season. According to our analysis, the concentration of nutrient elements were arranged as Ca>Mg>N>K>Fe>P>Cu>Mn for rainfall, K>N>Mg>Ca>P>Fe>Mn>Cu for throughfall, and Mn>P>K>Cu>Fe>N>Mg>Ca for being leached through canopy. Nutrients concentration in stewflow and throughfall changed significantly when rainfall passed canopy, and concentration of all elements increased except for Ca and Mg. 展开更多
关键词 Broadleaved/Korean pine forest Precipitation distribution Concentration Nutrient elements CANOPY STEMFLOW THROUGHFALL INTERCEPTION
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Functional evaluation for effective compositions in seed oil of Korean pine 被引量:14
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作者 王振宇 陈小强 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期215-217,共3页
The effect of seed oil of Korean pine (Pinus koraiensis) on the rats' blood-fat and its anti-ageing function was stud-ied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were ra... The effect of seed oil of Korean pine (Pinus koraiensis) on the rats' blood-fat and its anti-ageing function was stud-ied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were randomly divided into 5 groups (half males and half females in each group) as normal control group, high fat diet control group, and three groups (Group 1 Group 2, Group 3) that were fed with feedstuff with the contents of the seed oil of 2.0g/(kgd-1), 4.0g/(kgd-1) and 8.0g/(kgd-1), respec-tively. The indexes such as superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and anti-oxidation capacity (AOC) were measured by Reagent Kit method. It was found that the seed oil of the Korean pine could reduce the content of triglyc-eride and improve SOD as well as GSH-PX activity in serum. These indexes of the rats in Group 2 fed with Korean pine seed oil of 4.0 g/(kgd-1) reached the significant level and those of rats in Group 3 fed with the seed oil of 8.0 g/(kgd-1) reached the extremely significant level. The results indicated the seed oil of Korean pine had function of regulating the level of blood-fat and anti-ageing. 展开更多
关键词 Korean pine seed oil Effective compositions Functional evaluation Blood-fat ANTI-AGEING
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Storage dynamics of fallen trees in a mixed broadleaved and Korean pine forest 被引量:3
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作者 代力民 陈高 +3 位作者 邓红兵 徐振邦 李扬 陈华 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期107-110,共4页
A study of the storage dynamics in the mixed broadleaved and Korean pine forests was carried out in the Changbai Mountains, Jilin Province, P. R. China. The modifying law of fallen trees was the storage dynamics of th... A study of the storage dynamics in the mixed broadleaved and Korean pine forests was carried out in the Changbai Mountains, Jilin Province, P. R. China. The modifying law of fallen trees was the storage dynamics of the existing fallen trees and the annual input in the mixed broadleaved and Korean pine forest. The current storage of fallen trees was 16.25 t昲m-2 in the initially, but after 100 years, 85% of the storage in dry weight was decomposed, and little material was left after 300 years. The average annual input of fallen trees was 0.6 t昲m-2and it increased with time to 31.0 t昲m-2after 200 years, which was maintained until the climax community ended. The total storage of fallen trees increased in the early stage. The decomposition of fallen trees eventually reached equilibrium with storage being identical with the annual input of fallen trees. 展开更多
关键词 Broadleaved/Korean pine forest STORAGE DYNAMICS Fallen trees Changbai Mountains.
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A new methodology for estimating forest NPP based on forest in-ventory data——a case study of Chinese pine forest 被引量:6
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作者 赵敏 周广胜 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期93-100,i001,共9页
Accurately estimating forest net primary productivity (NPP) plays an important role in study of global carbon budget. A NPP model reflecting the synthetic effects of both biotic (forest stand age, A and stem volume, V... Accurately estimating forest net primary productivity (NPP) plays an important role in study of global carbon budget. A NPP model reflecting the synthetic effects of both biotic (forest stand age, A and stem volume, V) and climatic factors (mean annual actual evapotranspiration, E) was developed for Chinese pine (Pinus tabulaeformis) forest by making full use of Forest Inventory Data (FID) and dynamically assessing forest productivity. The NPP of Chinese pine forest was estimated by using this model and the fourth FID (1989–1993), and the spatial pattern of NPP of Chinese pine forest was given by Geography Information System (GIS) software. The results indicated that mean NPP value, of Chinese pine forest was 7.82 t m?2·a?1 and varied at the range of 3.32–11.87 t hm?2·a?1. NPP distribution of Chinese pine forests was significantly different in different regions, higher in the south and lower in the north of China. In terms of the main distribution regions of Chinese pine, the NPPs of Chinese pine forest in Shanxi and Shaanxi provinces were in middle level, with an average NPP of 7.4 t hm?2·a?1, that in the southern and the eastern parts (e.g. Shichuang Hunan, Henan, and Liaoning provinces) was higher (over 7.7 t hm?2·a?1), and that in the northern part and western part (e.g. Neimenggu and Ningxia provinces) was lower (below 5 t hm?2·a?1). This study provides an efficient way for using FID to understand the dynamics of foest NPP and evaluate its effects on global climate change. Keywords Forest NPP - Forest inventory data - Chinese pine forest - Climatic and biotic NPP model - Spatial distribution pattern CLC number S727.22 - S757.2 Document code A Foundation item: This study was supported by the National Natural Science Foundation of China (Nos. 30028001, 49905005), National Key Basic Research Specific Foundation (G1999043407); the Chinese Academy of Sciences (KSC2-1-07).Biography: ZHAO Min (1973-), female, Ph. D. in Laboratory of Quantitative Vegetation Ecology, Institute of Botany, the Chinese Academy of Sciences, Beijing 100093, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Forest NPP Forest inventory data Chinese pine forest Climatic and biotic NPP model Spatial distribution pattern
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