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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:24
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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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牛角藓(Cratoneuron filicinum (Hedw.) Spruce)叶片形态特征的生态变异及其分类学意义 被引量:4
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作者 吴玉环 罗昊 +1 位作者 李微 高谦 《生态学杂志》 CAS CSCD 北大核心 2007年第6期882-885,共4页
对200份牛角藓(Cratoneuron filicinum)标本的叶片长度、叶片宽度、中肋基部宽度、叶片中部细胞的宽度和长度、角部细胞的宽度和长度及叶片弯曲程度等特征进行线性回归分析。结果表明,在较低样本量时,来源于不同生境的牛角藓叶片各性状... 对200份牛角藓(Cratoneuron filicinum)标本的叶片长度、叶片宽度、中肋基部宽度、叶片中部细胞的宽度和长度、角部细胞的宽度和长度及叶片弯曲程度等特征进行线性回归分析。结果表明,在较低样本量时,来源于不同生境的牛角藓叶片各性状特征间的线性相关性不显著,来源于水生群落的牛角藓叶片各性状特征间的线性相关性显著。在样本量较大时,牛角藓叶片各性状特征间的线性关系相关性显著。说明牛角藓叶片的某些特征在自然选择压力下发生了变化,表现出较高的遗传多样性;这些特征虽然受环境影响而在形态上表现出变异,但总的趋势是相似的。 展开更多
关键词 牛角藓 生境 叶片特征
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Drought can favour the growth of small in relation to tall trees in mature stands of Norway spruce and European beech 被引量:2
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作者 Hans Pretzsch Gerhard Schutze Peter Biber 《Forest Ecosystems》 SCIE CSCD 2018年第3期258-276,共19页
Background: Climate change triggered many studies showing that trends and events of environmental conditions can reduce but also accelerate growth at the stand and individual tree level. However, it is still rather un... Background: Climate change triggered many studies showing that trends and events of environmental conditions can reduce but also accelerate growth at the stand and individual tree level. However, it is still rather unknown how climate change modifies the growth partitioning between the trees in forest stands.Methods: Based on long-term girth-tape measurements in mature monospecific and mixed-species stands of Norway spruce(Picea abies(L.) Karst.) and European beech(Fagus sylvatica L.) we traced the effect of the severe droughts in 2003 and 2015 from the stand down to the tree level.Results: Stand growth of Norway spruce decreased by about 30% in the once-in-a-century drought 2015, while European beech was much more drought resistant. Water availability generally amplified size-asymmetric growth partitioning. Especially in case of Norway spruce water availability primarily fostered the growth of predominant trees, whereas drought favoured the growth of small trees at the expense of the predominant ones. We could not detect significant differences between mixed and monospecific stands in this regard.Conclusions: The drought-induced reallocation of growth in favour of small trees in case of spruce may result from its isohydric character. We hypothesize that as small trees are shaded, they can benefit from the reduced water consumption of their sun-exposed taller neighbours. In case of beech, as an anisohydric species, tall trees suffer less and smaller trees benefit less under drought. The discussion elaborates the consequences of the water dependent growth allocation for forest monitoring, growth modelling, and silviculture. 展开更多
关键词 Growth partitioning DROUGHT Competition symmetry Climate change Norway spruce European beech
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Investigation of interactive effects of acid fog and ozone on spruce seedlings 被引量:1
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作者 Zou Siwei Zhu Lianxi(Department of Environmental Science and Engineering, Chengdu University of Scienceand Technology , Chengdu 610065 , China)B. Prinz(Department 4 Landesanstdlt fur Immissionsschutz, NRW. 45133 Essen. Germany) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第2期176-182,共7页
Ozone and acidic fog are considered as two important factors to cause forest decline. In this study ,laboratory experiment was carried out to simulate the effects of rnountainous air pollution on spruce seedlingsat hi... Ozone and acidic fog are considered as two important factors to cause forest decline. In this study ,laboratory experiment was carried out to simulate the effects of rnountainous air pollution on spruce seedlingsat high altitude with high content of ozone 展开更多
关键词 air POLLUTANT forest DECLINE acidic FOG OZONE spruce.
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Tree-ring δ^(15)N of Qinghai spruce in the central Qilian Mountains of China:Is pre-treatment of wood samples necessary? 被引量:1
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作者 WANG Ziyi LIU Xiaohong +5 位作者 WANG Keyi ZENG Xiaomin ZHANG Yu GE Wensen KANG Huhu LU Qiangqiang 《Journal of Arid Land》 SCIE CSCD 2022年第6期673-690,共18页
A knowledge of the tree-ring stable nitrogen isotope ratio(δ^(15)N)can deepen our understanding of forest ecosystem dynamics by indicating the long-term availability,cycling and sources of nitrogen(N).However,the rad... A knowledge of the tree-ring stable nitrogen isotope ratio(δ^(15)N)can deepen our understanding of forest ecosystem dynamics by indicating the long-term availability,cycling and sources of nitrogen(N).However,the radial mobility of N blurs the interannual variations in the long-term N records.Previous studies of the chemical extraction of tree rings before analysis had produced inconsistent results and it is still unclear whether it is necessary to pre-treat wood samples from specific tree species to remove soluble N compounds before determining theδ^(15)N values.We compared the effects of pre-treatment with organic solvents and hot ultrapure water on the N concentration andδ^(15)N of tree rings from endemic Qinghai spruce(Picea crassifolia)growing in the interior of the central Qilian Mountains,China,during the last 60 a.We assessed the effects of different preparation protocols on the removal of the labile N compounds and investigated the need to pre-treat wood samples before determining theδ^(15)N values of tree rings.Increasing trends of the tree-ring N concentration were consistently observed in both the extracted and unextracted wood samples.The total N removed by extraction with organic solvents was about 17.60%,with a significantly higher amount in the sapwood section(P<0.01).Theδ^(15)N values of tree rings decreased consistently from 1960 to 2019 in both the extracted and unextracted wood samples.Extraction with organic solvents increased theδ^(15)N values markedly by about 5.2‰and reduced the variations in theδ^(15)N series.However,extraction with hot ultrapure water had little effect,with only a slight decrease in theδ^(15)N values of about 0.5‰.Our results showed that the radial pattern in the inter-ring movement of N in Qinghai spruce was not minimized by extraction with either organic solvents or hot ultrapure water.It is unnecessary to conduct hot ultrapure water extraction for the wood samples from Qinghai spruce because of its negligible effect on the removal of the labile N.Theδ^(15)N variation trend of tree rings in the unextracted wood samples was not influenced by the heartwood-sapwood transition zone.We suggest that theδ^(15)N values of the unextracted wood samples of the climate-sensitive Qinghai spruce could be used to explore the ecophysiological dynamics while focusing on the long-term variations. 展开更多
关键词 tree rings stable nitrogen isotope ratio(δ^(15)N) nitrogen concentration solvent-extracted wood water-extracted wood wood pre-treatment Qinghai spruce Qilian Mountains
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Biomass and net productivity for spruce plantation
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作者 马承惠 穆丽蔷 +2 位作者 姚忠良 刘鹏 孙剑峰 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第1期45-47,共3页
云杉(Picea koraiensis ) 的生物资源在 Heilongjiang 省的 Suiling 区域的种植园系统地被学习。网生产率和他们茎的分发生物资源,吠叫,从 6 ~ 31 的云杉种植园的乔木的层上的分支,叶和根一被调查并且起源分析使用吝啬的样品方法。... 云杉(Picea koraiensis ) 的生物资源在 Heilongjiang 省的 Suiling 区域的种植园系统地被学习。网生产率和他们茎的分发生物资源,吠叫,从 6 ~ 31 的云杉种植园的乔木的层上的分支,叶和根一被调查并且起源分析使用吝啬的样品方法。为估计单个树的不同机关的生物资源被建立的回归方程。结果证明看台的生物资源 151 是 t/hm ? 2 并且网生产率是 1114 t/(hm2 吗?? 展开更多
关键词 spruce PICEA koraiensis PLANTATION BIOMASS NET PRODUCTIVITY
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Crown Morphology of Norway Spruce from Usual Tree Measurements
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作者 李长胜 孙剑峰 徐永芳 《Journal of Forestry Research》 SCIE CAS CSCD 1998年第1期8-12,共5页
The crown morphology of Norway sprce (Picea abies Karst) was studicd from 617 sample trees. In order to model branch and crown descriptors the linear and nonlinear regression methods were extensively used. Results sho... The crown morphology of Norway sprce (Picea abies Karst) was studicd from 617 sample trees. In order to model branch and crown descriptors the linear and nonlinear regression methods were extensively used. Results show that the branch length can be fairly well predicted from the distance to the apex of the free and that the branch spread has a high correlation with the branch length and the insertion angle. Models have been set up to predict the crown ratio, height to the base of the living crown, height to the first living branch and the height to the first dead branch from the usual whole-tree measurements, namely diameter at breast height, total height and total age. 展开更多
关键词 CROWN MORPHOLOGY Branchiness CROWN ratio Norway spruce PICEA ABIES KARST Modeling Wood quality
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ARTIFICIAL REGENERATION OF KOREAN SPRUCE IN NORTHEAST CHINA
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作者 Zhan Hongzhcn (1) Zhang Tongwei (1) Wang Fengyou (1) 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1990年第1期11-15,共5页
Korean spruce(Picea koraiensis Nakai)has been included as a Chinese regenerationspecies since the 1960’s.In the 1970’s it became one of the four most important species in thenortheast forest region of China. Korean ... Korean spruce(Picea koraiensis Nakai)has been included as a Chinese regenerationspecies since the 1960’s.In the 1970’s it became one of the four most important species in thenortheast forest region of China. Korean spruce is a timber species with a wide range of adaptation,high survival rate,and few diseases or pests.Studies of 30—year trials show that the regeneration ofkorean spruce is successful and has a prospective future. 展开更多
关键词 Korcan spruce FOREST regencration CONIFER regencration
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Spatiotemporal evidence of tree-growth resilience to climate variations for Yezo spruce(Picea jezoensis var. komarovii) on Changbai Mountain, Northeast China
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作者 Xuerui Gai Shoule Wang +6 位作者 Li Zhou Jian Wu Wangming Zhou Jianhua Bi Linlin Cao Limin Dai Dapao Yu 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第3期927-936,共10页
Global warming-induced changes in tree-growth resilience to climate variations have been widely reported for mid-and high-latitude regions around the world. Most studies have focused on the spatial variability of tree... Global warming-induced changes in tree-growth resilience to climate variations have been widely reported for mid-and high-latitude regions around the world. Most studies have focused on the spatial variability of trees in radial growth-climate relationships on Changbai Mountain in Northeast China, but little is known about temporal changes in tree growth in response to climate. We explored the stability of effect of climate variables on radial growth of Yezo spruce [Picea jezoensis Carr. var. komarovii(V.Vassil.) Cheng et L.K.Fu] at 1200, 1400, and 1600 m above sea level, representing low, middle, and upper ranges of the spruce-fir mixed forest on Changbai Mountain. The results showed that the relation between tree growth and climate did not vary with altitude, but the stability of the tree-growth-climate relationship did vary with altitude as the climate changed. Radial growth of Yezo spruce at allthree elevations was influenced primarily by maximum temperature during May(Tmax5) and mean minimum temperature from January to March(Tmin1-3). More specifically, the relationship strengthened significantly at lower elevations, but weakened significantly at higher elevation, and fluctuated at mid elevations since 1980.Increase in Tmin1-3 and decrease in Tmax5 were the main reasons for the decrease in the radial growth at three altitudes. The findings of this study clarified that the decrease in radial growth on Changbai Mountain is not a “divergence problem” of an unexpected decrease in tree growth in response to an increase in mean temperature and provides a reference for using tree-ring data to reconstruct climate patterns and/or predict the growth of trees under various climate change scenarios. 展开更多
关键词 Altitudinal gradient Changbai MOUNTAIN Ring width SPATIOTEMPORAL stability Yezo spruce
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Modeling the dynamics of a spruce forest and dwarf mistletoe population:a coupled system
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作者 Dianguang Xiong Zhouyuan Li +1 位作者 Yingmei Liang Chengming Tian 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第4期1579-1585,共7页
The parasitic plant dwarf mistletoe(Arceuthobium) is currently one of the most threatening infestations of coniferous forests worldwide,especially in Eurasia and North America,but its population dynamics in relation t... The parasitic plant dwarf mistletoe(Arceuthobium) is currently one of the most threatening infestations of coniferous forests worldwide,especially in Eurasia and North America,but its population dynamics in relation to one of its hosts(spruce) remain unclear.Here,toward understanding the population dynamics,differential equations were used to construct a life history model for the two populations,and two relatively independent subsystems,host and parasite,were generated from their symbiotic relationships.A suspected-infection model was used to couple them.The resulting models were used to analyze structural changes in the forest.When each infected spruce was assumed to support 1000 parasite shoots,the spruce population first increased rapidly,then slows.When 2000 parasite shoots were assumed,the forest declined dramatically,slipping to zero in the 10 th year,and the spruce seedlings were unable to regenerate.Parasite shoot population curves transformed from exponential J-shapes to logistic S-shapes,reaching population limitations as germination rates changed.These results provide important clues to understanding developmental trends of the present parasite population and will assist in reconstructing invasion histories. 展开更多
关键词 Dwarf mistletoe spruce Population dynamic model
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Paludification reduces black spruce growth rate but does not alter tree water use efficiency in Canadian boreal forested peatlands
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作者 Joannie Beaulne Étienne Boucher +1 位作者 Michelle Garneau Gabriel Magnan 《Forest Ecosystems》 SCIE CSCD 2021年第2期373-386,共14页
Background:Black spruce(Picea mariana(Mill.)BSP)-forested peatlands are widespread ecosystems in boreal North America in which peat accumulation,known as the paludification process,has been shown to induce forest grow... Background:Black spruce(Picea mariana(Mill.)BSP)-forested peatlands are widespread ecosystems in boreal North America in which peat accumulation,known as the paludification process,has been shown to induce forest growth decline.The continuously evolving environmental conditions(e.g.,water table rise,increasing peat thickness)in paludified forests may require tree growth mechanism adjustments over time.In this study,we investigate tree ecophysiological mechanisms along a paludification gradient in a boreal forested peatland of eastern Canada by combining peat-based and tree-ring analyses.Carbon and oxygen stable isotopes in tree rings are used to document changes in carbon assimilation rates,stomatal conductance,and water use efficiency.In addition,paleohydrological analyses are performed to evaluate the dynamical ecophysiological adjustments of black spruce trees to site-specific water table variations.Results:Increasing peat accumulation considerably impacts forest growth,but no significant differences in tree water use efficiency(iWUE)are found between the study sites.Tree-ring isotopic analysis indicates no iWUE decrease over the last 100 years,but rather an important increase at each site up to the 1980 s,before iWUE stabilized.Surprisingly,inferred basal area increments do not reflect such trends.Therefore,iWUE variations do not reflect tree ecophysiological adjustments required by changes in growing conditions.Local water table variations induce no changes in ecophysiological mechanisms,but a synchronous shift in iWUE is observed at all sites in the mid-1980 s.Conclusions:Our study shows that paludification induces black spruce growth decline without altering tree water use efficiency in boreal forested peatlands.These findings highlight that failing to account for paludification-related carbon use and allocation could result in the overestimation of aboveground biomass production in paludified sites.Further research on carbon allocation strategies is of utmost importance to understand the carbon sink capacity of these widespread ecosystems in the context of climate change,and to make appropriate forest management decisions in the boreal biome. 展开更多
关键词 Black spruce growth Boreal biome Carbon allocation Ecophysiological mechanisms Forested peatland Paludification Stable isotope Water use efficiency
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Assessing Soil-Related Black Spruce and White Spruce Plantation Productivity
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作者 Shane Furze Mark Castonguay +5 位作者 Jae Ogilvie Mina Nasr Pierre Cormier Rolland Gagnon Greg Adams Paul A. Arp 《Open Journal of Forestry》 2017年第2期209-227,共19页
This article focuses on modelling and mapping the productivity of black (Picea mariana) and white spruce (Picea glauca) plantations across the Black Brook forest management area in northwestern New Brunswick, Canada, ... This article focuses on modelling and mapping the productivity of black (Picea mariana) and white spruce (Picea glauca) plantations across the Black Brook forest management area in northwestern New Brunswick, Canada, encompassing about 200,000 ha. This effort involved establishing 3500 50 m2 survey plots, each informing about: plantation age (15 to 43 years), planted species type, stem count, tree height, basal area, and wood volume. All of this was supplemented with location-specific productivity predictors, i.e., xy location and specifications pertaining to soil type, soil drainage (established through digital elevation modelling by way of the depth-to-water index DTW), and years since thinning (pre-commercial and commercial), and. The DTW index, as it emulates the elevation rise away from open water features such as streams, rivers and lakes, allowed the re-mapping of existing soil borders by topographic position and drainage association. Non-linear regression analysis revealed that plantation height, basal area and volume all increased with plantation age, as to be expected. Pre-commercial thinning in plantations <30 years old had a positive while the more recent commercial thinning still had the negative effect on standing wood volume and mean annual volume increment (MAI). White spruce MAI generally exceeded black spruce (MAI) by a factor of 1.25. Poor and excessive soil drainage reduced MAI. Best growth performances occurred on plantations established on well-drained calcareous soils. The best-fitted results so obtained allowed for generating black and white spruce MAI maps across the forest management area by ridge-to-valley soil and DTW location at 10 m resolution. These maps were subsequently used for site-by-site silvicultural evaluation and ranking purposes. 展开更多
关键词 Forest PLANTATION PRODUCTIVITY Mapping Black spruce WHITE spruce SOIL Type & Drainage Digital TERRAIN Modelling
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Genetic variation of Norway spruce clones regarding their natural durability, physical and chemical properties
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作者 Ilze Irbe Guna Noldt +3 位作者 Uldis Grinfelds Anrijs Verovkins Aris Jansons Gerald Koch 《Advances in Bioscience and Biotechnology》 2012年第8期1104-1112,共9页
Genetic variation of ten Norway spruce (Picea abies (L.) Karst.) clones regarding their decay resistance against brown rot fungi, as well as physical and chemical properties of clones were investigated. 31- year-old s... Genetic variation of ten Norway spruce (Picea abies (L.) Karst.) clones regarding their decay resistance against brown rot fungi, as well as physical and chemical properties of clones were investigated. 31- year-old spruce clones: 26, 31, A10, A15, A7, B10, B15, B6, V7, V9 were selected across Latvia. The stem diameters of spruce clones varied between 13.0 and 20.9 cm. The wood density of clones ranged from 361 to 443 kg/m3. Klason lignin content, depending on the clone, was between 27.0%-28.9%. Cellular UV microspectrophotometry of the non-infected tracheids displayed the typical lignin distribution with highest absorbance values in the cell corners (abs280 nm 0.80) and compound middle lamellae (abs280 nm 0.48), while secondary wall showed lower lignin absorbance values (abs280 nm0.29 - 0.35). The deposition of phenolic extractives in ray parenchyma and epithelial cells of resin canals were emphasized by a significantly higher UV-absorbance (abs280 nm 0.68 to 0.78) when compared to the cell wall associated lignin. The content of acetone-soluble extractives of spruce clones varied between 1.1% - 1.8%. The x-value (natural durability) for all spruce clones after exposure to C. puteana and P. placentawas >0.90 (durability class 5, not durable). Most of clones after degradation by G. trabeum had x-value > 0.90 with exception of clones B15 and V9 that showed x-value ≤ 0.90 (durability class 4, slightly durable). Natural durability of spruce clones did not correlate with stem diameter, density, content of lignin and extractives. 展开更多
关键词 Norway spruce CLONES Natural Durability Brown ROT Lignin EXTRACTIVES Density UV MICROSPECTROPHOTOMETRY
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Essential Oil from Ether-Containing Plants of Juniper (<i>Juniperus</i>) and Spruce (<i>Picea</i>) Leaves by Distillation
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作者 Baktygul Abylaeva Tilebaldy Abdulazizov +3 位作者 Zamira Sandybaeva Zhypargul Abdullaeva Ernis Bepiev Zakhro Akhmedova 《Green and Sustainable Chemistry》 2020年第4期109-116,共8页
This article is investigating the preparation of essential oil from the ether-containing plants of Juniper (</span></span><span style="font-family:Verdana;"><span style="font-family... This article is investigating the preparation of essential oil from the ether-containing plants of Juniper (</span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Juniperus</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">) and spruce (</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Picea</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">) leaves by using the simple water distillation equipment. This water distillation method forms an essential oil with water vapor from plants of Juniper (</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Juniperus</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">) and spruce (</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Picea</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">) leaves based on Dalton’s law</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">of</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">partial pressure, applicable for plants containing a large amount of ether oil where distillation temperature is </span><span style="font-family:Verdana;">not affecting product quality. Obtained essential oils are widely used in medicine, perfumery, cosmetics, and food industry. In addition, these essential oi</span><span style="font-family:Verdana;">ls possess different activities including antimicrobial, antiviral, and anti-inflammatory, which have different effects such as adaptogenic, antidepressive, disinfection, and wound healing, diuretic, and antipyretic</span>. 展开更多
关键词 Essential Oil Extract JUNIPER spruce LEAVES DISTILLATION Yield
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GPR Survey for Fir(Abies alba)and Spruce(Picea abies)Root Systems in Different Locations in the Western Carpathians Mts.(Poland)
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作者 Bozena Potepa Adam Szynkiewicz Magdalena Udyrysz-Krawec 《Journal of Geological Resource and Engineering》 2018年第5期194-209,共16页
The aim of the GPR research was a non-invasive inspection of the root systems arrangement of selected trees(fir Abies alba and spruce Picea abies),in the Silesian Beskids Landscaped Park and Zywiec Beskids Landscaped ... The aim of the GPR research was a non-invasive inspection of the root systems arrangement of selected trees(fir Abies alba and spruce Picea abies),in the Silesian Beskids Landscaped Park and Zywiec Beskids Landscaped Park(Carpathian Mountains,Poland).Field research has been done using RAMAC/GPR with 800 MHz shielded antennas.The survey was conducted by linear profiling to a depth of 2 m.The survey was carried out around the designated trees in 6 meters×6 meters grids.Base points for X(S-N)and Y(W-E)axis were set in corners of each grid.Parallel GPR traverses were conducted within each study area,at intervals of 0.20 m.The maps of the research areas show existing trees and stumps within the GPR sections,with ±1 m error.GPR data analysis was carried out in 2D and 3D systems.Major findings from the GPR survey concluded that the firs(Abies alba),have a "vertical" root system type(with the roots dominant at depths of 0.2-0.8 meters),concentrically away from the tree trunk at a distance of about 1 m to about 2 m,and the spruces(Picea abies),have a "cloud" root system type(at a depth of 10-100 cm),with a few clear,thicker roots extending from the trunk. 展开更多
关键词 GPR ROOT systems FIR and spruce Carpathian Mts. Poland.
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Forest Response to the US 1990 Clean Air Act: The Southern Spruce-Fir Ecosystem
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作者 Stephen A. Banks 《American Journal of Plant Sciences》 2014年第3期372-386,共15页
The history of the Black Mountains in North Carolina and the southern Spruce-Fir ecosystem has been fraught with widespread forest decline since the mid 1960’s. Balsam Woolly Adelgid attacks and acidic deposition wer... The history of the Black Mountains in North Carolina and the southern Spruce-Fir ecosystem has been fraught with widespread forest decline since the mid 1960’s. Balsam Woolly Adelgid attacks and acidic deposition were two of the most recognized causes of decline. Uncertainty arose about the future of these forests, and projections were made regarding the endangerment or extinction of the endemic Fraser fir ([Pursh] Poiret). This study analyzed data sets from a permanent plot network in the Black Mountains dating 1985, 2002, and 2012. Indications that the Fraser fir population is stabilizing from a “boom-bust” cycle of population growth and has entered the stem exclusion stage of forest stand development are evident. Fir live stem density increased more than 250% from 1985 to 2002, and then declined 40% by 2012 at the highest elevations in the forest. Overall, fir appeared to be more impacted on western facing slopes than eastern ones. The population of red spruce experienced a steady decrease in live stem counts, but an increase in live basal area through all years, and at all elevation classes (1675 m, 1830 m, and 1980 m), indicating a normal progression through stand development. Red spruce was also most negatively impacted on western facing slopes. Live stem density was significantly higher (P 0.001) than eastern plots, but live basal area was similar between the two aspects. Atmospheric deposition concentrations of the four main acidic molecules at Mt. Mitchell all peaked in 1998, but decreased by 2012. These reductions, occurring shortly after tightened regulations in the 1990 amendments to the Clean Air Act may have potential implications for increased forest resilience. 展开更多
关键词 Southern spruce-FIR BALSAM Woolly Adelgid FOREST STAND Development FOREST RESPONSE FOREST Regeneration Atmospheric Deposition FOREST DECLINE
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Checking of Radially Sawn Scots Pine and Norway Spruce Wood
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作者 Martti Venäläinen Yonggang Hu Erkki Verkasalo 《Natural Resources》 2016年第9期505-514,共11页
In exterior use, wood is subjected to weathering that causes checking and other deterioration in the appearance and technical properties. We studied quantitatively the surface checking of radially and tangentially saw... In exterior use, wood is subjected to weathering that causes checking and other deterioration in the appearance and technical properties. We studied quantitatively the surface checking of radially and tangentially sawn specimens of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies Karst.) wood in a cyclic climate chamber test. The results strongly suggested that the sawing direction determines the checking performance of both Scots pine and Norway spruce wood. The radial surface of Scots pine specimens had 62% less checks than the tangential one, and the cumulative area of checks was 74% smaller. For Norway spruce, the respective figures were: 83% less in the check number and 91% less in the check area. Different from pine, in spruce specimens the checks of radial surface were significantly smaller. Thus, spruce timber gained clearly more about radial sawing pattern. The effect of annual ring width was similar for pine and spruce: the reduction in annual growth worsened the checking. The increase in density worsened the checking of spruce but did not change the performance of pine. In pine wood, the increase of heartwood proportion reduced the fluctuation of moisture content and the formation of checks. 展开更多
关键词 Scots Pine Norway spruce CHECKING Sawing Pattern Moisture Content WEATHERING
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Behavior of Decayed Spruce (Picea abies) during Kraft Pulping
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作者 Markku Halonen Raimo Alén 《Paper And Biomaterials》 2020年第4期1-7,共7页
This study indicated that by applying an improved classification system to decayed large-diameter Norway spruce(Picea abies)wood,its use as raw material for kraft pulping without loss of pulp quality could be essentia... This study indicated that by applying an improved classification system to decayed large-diameter Norway spruce(Picea abies)wood,its use as raw material for kraft pulping without loss of pulp quality could be essentially increased.This is based on the fact that although the cooking yield of decayed spruce material which has been sorted according to these new recommendations is somewhat lower and Kappa number higher than those of sound wood material,the greatest part of the decayed stem(the outer part of the stem)contains long-fiber wood material which produces pulp of good quality.Therefore,large-diameter spruce logs can also be separately used,for example,in the manufacture of reinforcement pulp. 展开更多
关键词 Norway spruce kraft pulping wood decay fungal decay soft rot
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Lichen-Spruce Woodland Early Indicators of Ecological Resilience Following Silvicultural Disturbances in Québec’s Closed-Crown Forest Zone
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作者 Esteban Gonzalez Francois Hébert +2 位作者 Jean-Francois Boucher Pascal Sirois Daniel Lord 《American Journal of Plant Sciences》 2013年第3期749-765,共17页
Lichen woodlands (LW) located in the closed-crown boreal forest are not a successional stage moving towards a closed black spruce feathermoss stand (FM), but an alternative stable state, due to their previous forest h... Lichen woodlands (LW) located in the closed-crown boreal forest are not a successional stage moving towards a closed black spruce feathermoss stand (FM), but an alternative stable state, due to their previous forest history, and the occurrence of LWs located nearby closed-crown FM stands. Therefore, afforestation in those LWs through site preparation and plantation could shift back LW into FM stands. We implemented an experimental design with different combinations of silvicultural treatments in both site types (LW, FM). We monitored the evolution of plant diversity and the physiology of three bio-indicators (Picea mariana, Kalmia angustifolia, Rhododendron groenlandicum) in different microsites created by the silvicultural treatments. The return to the initial composition was noticed only two years after treatments, especially in the LW stands, thus indicating a higher level of early ecosystem resilience in LWs compared to FM stands. Mean species cover, especially in the FM stands, decreased the most in the skid trails created by logging, probably due to a lack of acclimation of bryophytes to open stand conditions. Conversely, ericaceous shrubs and lichens found in the LWs were already acclimated to open stand conditions, which give to LWs a restructuring advantage compared to FM plant communities after silvicultural treatments. Overall, FM and LW short-term resilience was similar, indicating equally efficient ecosystem reorganization in both stands. The comparable early resilience in managed LW and FM stands, in terms of plant biodiversity, contradicts the presumed fragility of LW stands, especially in this case where LWs are assumed to be an alternative stable state created by compound disturbances. Silvicultural treatments maintained the functional group diversity in LWs, a key element for ecosystem resilience. Therefore, this study support the idea that plantation following site preparation in LWs could be a valuable management strategy to reach several objectives, such as increasing forest carbon sinks. 展开更多
关键词 AFFORESTATION Black spruce Kalmia angustifolia Rhododendron groenlandicum LOGGING Picea mariana Vegetation Recovery SCARIFICATION SILVICULTURE
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Soil Enzyme Activity Changes in Different-Aged Spruce Forests of the Eastern Qinghai-Tibetan Plateau 被引量:46
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作者 ZHANGYong-Mei ZHOUGuo-Yi +1 位作者 WUNing BAOWei-Kai 《Pedosphere》 SCIE CAS CSCD 2004年第3期305-312,共8页
Activities of selected soil enzymes (invertase, acid phosphatase, proteinase, catalase, peroxidase and polyphenoloxidase) were determined under different spruce forests with restoration histories of 5, 13, 18, 23, 27 ... Activities of selected soil enzymes (invertase, acid phosphatase, proteinase, catalase, peroxidase and polyphenoloxidase) were determined under different spruce forests with restoration histories of 5, 13, 18, 23, 27 years and an old growth forest over 400 years old in the eastern Qinghai-Tibetan Plateau, China, and their possible use as indicators of ecosystems health were analyzed. Plots 10 × 10 m with 4 replications were established to investigate three hypotheses: soil enzyme activities a) would increase with the restoration process; b) would be greater in surface soils than at lower depths; and c)would be correlated to selected physicochemical properties. Results showed that as the forests developed after restoration,invertase and peroxidase activities usually increased up to the 23 year point. Also soil enzyme activities were associated with surface soils and decreased with depths, suggesting that in earlier restoration stages surface addition of organic fertilizer to soils might be more effective than additions at depth. In the 0-20 cm soil, there were significant correlations (P < 0.01 or < 0.05) between some soil enzyme activities and some selected chemical properties. Therefore, temporal changes in enzyme activities should be included as an indicator when evaluating sustainable forest management practices. 展开更多
关键词 磷酸酶 过氧化氢酶 转化酵素 过氧化酶 云杉林 土壤酶
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