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栖霞市生木树泥石流隐患点发育特征及发展趋势分析评价 被引量:3
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作者 张生海 韩明智 +1 位作者 高松 白莹 《山东国土资源》 2019年第12期40-45,共6页
栖霞市生木树泥石流隐患点为烟台市471处地质灾害隐患点其中1处,曾于1979年7月因暴雨引发泥石流灾害,给当地村民造成严重经济损失。以该泥石流沟流域作为研究区,并以区内泥石流发育的自然环境、基本特征及形成泥石流的地质条件、物源条... 栖霞市生木树泥石流隐患点为烟台市471处地质灾害隐患点其中1处,曾于1979年7月因暴雨引发泥石流灾害,给当地村民造成严重经济损失。以该泥石流沟流域作为研究区,并以区内泥石流发育的自然环境、基本特征及形成泥石流的地质条件、物源条件和水源条件等勘察成果为基础,综合分析区内泥石流发育特征、类型、形成机理、引发因素,并选取相关参数对泥石流基本特征值进行计算,为同类型泥石流的防治提供科学依据。综合研究确定区内泥石流易发程度为轻度易发,现阶段泥石流沟发展阶段为发展期,泥石流灾害趋于相对稳定,但一旦遭遇暴雨至特大暴雨,可能会再次引发泥石流地质灾害。 展开更多
关键词 泥石流 发育特征 形成机理 栖霞市生木树
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植物性染黑发色素—洋苏木树色素 附苏木树色素 被引量:3
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作者 刘新民 《北京日化》 2000年第3期6-12,共7页
本文从色素类别,组成成分,安全学性质,存在与资源,提取和分离,品项规定,开发利用以及贮存条件八个侧面详尽了当今国际化妆品界的新颖、热门和倍受关注的植物性长久性染黑发色素一洋苏木树色素。
关键词 植物性染黑发色素 洋苏 木树色素 染发素 化妆品
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富民富国 树木树人
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作者 姜益雄 《林业与生态》 1997年第7期6-6,共1页
关键词 森林蓄积量 木树 离退休老干部 宁乡县 国主义 经济林 生态体系 宜林荒山 基本消灭 国外松
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Role of outdoor trees on pedestrian wind and thermal conditions around a pre-education building for sustainable energy management
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作者 LI Xiao-jie TANG Hui-li 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2039-2053,共15页
Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian... Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian-level wind velocity and thermal condition.In this study,a numerical investigation is employed to assess the role of trees planted in the windward direction of the building complex on the thermal and pedestrian wind velocity conditions around/inside a pre-education building located in the center of the complex.Compared to the previous studies(which considered only outside buildings),this work considers the effects of trees on microclimate change both inside/outside buildings.Effects of different parameters including the leaf area density and number of trees,number of rows,far-field velocity magnitude,and thermal condition around the main building are assessed.The results show that the flow velocity in the spacing between the first-row buildings is reduced by 30%-40% when the one-row trees with 2 m height are planted 15 m farther than the buildings.Furthermore,two rows of trees are more effective in higher velocities and reduce the maximum velocity by about 50%.The investigation shows that trees also could reduce the temperature by about 1℃around the building. 展开更多
关键词 sustainable management energy trees urban area thermal condition building
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Vegetative Storage Proteins in Meliaceae 被引量:7
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作者 田维敏 吴继林 +1 位作者 郝秉中 胡正海 《Acta Botanica Sinica》 CSCD 2002年第2期242-245,共4页
采用光学和电子显微镜技术及SDS_PAGE研究了营养贮藏蛋白质 (VSPs)在楝科树木中的分布和超微结构 ;并采用免疫印迹技术 ,以大叶桃花心木 (SwieteniamacrophyllaKing)的 2 1kDVSP的抗血清检测楝科树木VSPs的免疫相关性。结果表明 ,在桃... 采用光学和电子显微镜技术及SDS_PAGE研究了营养贮藏蛋白质 (VSPs)在楝科树木中的分布和超微结构 ;并采用免疫印迹技术 ,以大叶桃花心木 (SwieteniamacrophyllaKing)的 2 1kDVSP的抗血清检测楝科树木VSPs的免疫相关性。结果表明 ,在桃花心木亚科 (Swietenioideae)的树木中普遍存在VSPs ,但楝亚科 (Melioidae)仅部分属的树木有VSPs而椿亚科 (Cedreloideae)树木没有VSPs。VSPs在同一属树木中的分布是一致的。桃花心木亚科和楝亚科树木之间的VSPs几乎没有免疫相关性 ,但是在桃花心木亚科中 ,VSPs具有相对高的同源性。楝科树木VSPs的超微结构存在一定程度的差异 ,这可能与VSPs的种类不同有关。VSPs的分布。 展开更多
关键词 vegetative storage proteins ULTRASTRUCTURE immuno-correlation MELIACEAE
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复合式合成词中应该有“同位型”的地位 被引量:2
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作者 傅力 《汉语学习》 CSSCI 北大核心 1989年第4期11-13,共3页
下面这些词在现代汉语里一般被判为“偏正型”(定中式)复合式合成词: 楠木树 松树 昆仑山 五台山 北京城 南京城 坦克车 卡车 芭雷舞 迪斯科舞 巧克力糖 可可 雪茄烟……这些词在日常生活中很常见,不胜枚举。它们有二个共同特点,就... 下面这些词在现代汉语里一般被判为“偏正型”(定中式)复合式合成词: 楠木树 松树 昆仑山 五台山 北京城 南京城 坦克车 卡车 芭雷舞 迪斯科舞 巧克力糖 可可 雪茄烟……这些词在日常生活中很常见,不胜枚举。它们有二个共同特点,就是前一个语素往往能单用(个别音译的单音语素如“卡车”的“卡”在现代汉语里不单用),单用时一般都可以表示整个词的意义。如: 展开更多
关键词 同位型 偏正型 复合式合成词 一个语素 “的” 坦克车 雪茄烟 木树 词组 种概念
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Sound absorption property of wood for five eucalypt species 被引量:7
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作者 江泽慧 赵荣军 费本华 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期207-210,共4页
The sound absorption coefficients of wood and wood boards for five eucalypt species (Eucalyptus urophylla, Euca-lyptus urophylla E. grandis, Eucalyptus urophylla E. tereticornis, Eucalyptus urophylla E. camaldulensis ... The sound absorption coefficients of wood and wood boards for five eucalypt species (Eucalyptus urophylla, Euca-lyptus urophylla E. grandis, Eucalyptus urophylla E. tereticornis, Eucalyptus urophylla E. camaldulensis and Eucalyptus cloeziana) that were collected from plantation in Dongmen Forestry Center of Guangxi Province, China were tested with stand-ing wave method and their sound absorption properties were also compared. The results showed that the sound absorption co-efficients of the five eucalypt wood species did not change evidently below 1000 Hz, but above 1000 Hz their sound absorption coefficients increased with the increasing frequency. The difference in sound absorption coefficient among five species of eucalypt wood is not evident at the tested frequency range (200-2000 Hz), but the sound absorption property of Eucalyptus urophylla at low frequency is better than that of other four species. The sound absorption coefficient of the tangential-sawn board is higher than that of the radial-sawn board. The sound absorption property of eucalypt wood of 0.5 cm in thickness is much better than that of 1.0 cm in thickness. It is concluded that wood sound absorption properties of eucalypts are affected by their board thickness and the type of sawn timber within the testing frequency, but the variance of wood sound absorption property among the five tested species is not significant. 展开更多
关键词 WOOD Standing wave method Sound absorption coefficient Eucalypt plantation
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Preparation of phenol formaldehyde resin from phenolated wood 被引量:8
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作者 李改云 秦特夫 +1 位作者 塔村真一郎 池田敦 《Journal of Forestry Research》 CAS CSCD 2004年第3期211-214,共4页
The technique for preparing phenol formaldehyde resin from phenolated wood (PWF) and its characters were studied and analyzed. Poplar (Populus spp.) wood meal was liquefied by phenol in the presence of sulfuric acid a... The technique for preparing phenol formaldehyde resin from phenolated wood (PWF) and its characters were studied and analyzed. Poplar (Populus spp.) wood meal was liquefied by phenol in the presence of sulfuric acid as a catalyst. After the liquefied products were cooled, alkaline catalyst and formaldehyde were added. The mixture was kept at (60?) C for 1h and then was heated to (85?) C for 1h. The influence of molar ratio of formaldehyde to phenol (F/P) was investigated. The results showed when the molar ratio of formaldehyde to phenol was over 1.8, the PWF adhesives had high bond quality, bond durability and extremely low aldehydes emissions. 展开更多
关键词 Phenolated wood Phenol formaldehyde (PF) adhesives Bond quality Bond durability Aldehyde emission.
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Effects of Climatic Factors on Tree-ring Maximum Latewood Density of Picea schrenkiana in Xinjiang, China 被引量:1
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作者 孙宇 王丽丽 尹红 《Agricultural Science & Technology》 CAS 2016年第6期1479-1487,共9页
Based on two tree-ring maximum latewood density (MXD) chronologies of Picea schrenkiana from the Manas River Basin, Xinjiang, the response characteristics of MXD to climate variation was discussed. Correlation analy... Based on two tree-ring maximum latewood density (MXD) chronologies of Picea schrenkiana from the Manas River Basin, Xinjiang, the response characteristics of MXD to climate variation was discussed. Correlation analysis between MXD chronologies and instrumental records from Shihezi meteorological station showed that each chronology was significantly and positively correlated with the maximum monthly average temperature in July-August, and especially, the regional chronology (RC) was the most highly correlated variable (r=0.54, P〈0.001). Afterwards, the maximum average temperature in July-August was reconstructed using RC. Comparison among reconstructed temperature, observed values, and the drought index (Is) confirmed that precipitation would affect MXD when the absolute value of Is is greater than 1.5σ (|Is| 〉 2.5 during 1953-2008) or near to 1.5a over a 2-3 year period. The response characteristics are related to the semiarid climate of the study area. In dry years, lack of precipitation would limit the thickening of latewood cell walls and, as a result, impact MXD. Therefore, compared with relatively humid regions, the response of tree-ring MXD to air temperature similarly would be influenced by extreme moisture conditions in semiarid areas, and MXD, as a temperature proxy, should be used prudently on a limited scale. 展开更多
关键词 Picea schrenkiana Tree ring Maximum latewood density Air temperature PRECIPITATION
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Screening and Taxonomic Status of a Highly Efficient Antifungal Strain against Cytospora chrysosperma 被引量:2
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作者 李冲伟 宋福强 宋瑞清 《Agricultural Science & Technology》 CAS 2015年第7期1352-1356,1406,共6页
In order to look for Trichderma strains which have inhibiting effects on Cytospora chrysosperma, total 29 domestic and foreign Trichderma strains were screened by confrontation culture and growth rate method. The phys... In order to look for Trichderma strains which have inhibiting effects on Cytospora chrysosperma, total 29 domestic and foreign Trichderma strains were screened by confrontation culture and growth rate method. The physiological ecology characteristics and taxonomic statuses of the screened highly efficient antifungal strains were studied. The results showed that the n-butanol extract from T-33 fer- mentation liquid showed the highest inhibition rate (94.2%) against mycelial growth, and its inhibition rate against spore germination was up to 100%. For the growth of T-33 strain, the optimum carbon source was glucose with optimum content of 3% (g/L); the optimum nitrogen source was soy four with optimum content of 0.02% (g/L); the optimum initial pH of culture medium was 6; the optimum culture temper- ature was 25 ℃. The 18S rDNA sequencing results showed that the full length of ITS sequence was 583 bp, and the T-33 strain was verified as Trichoderma viride. 展开更多
关键词 TRICHODERMA SCREENING Cytospora chrysosperma Molecular identification
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Use of the pilodyn for assessing wood properties in standing trees of Eucalyptus clones 被引量:3
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作者 吴世军 徐建民 +4 位作者 李光友 RISTO Vuokko 陆钊华 李宝琦 王伟 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期68-72,I0003,共6页
The effectiveness of pilodyn was tested in evaluating wood basic density, outer wood density, heartwood density, and modulus of elasticity (MoE) at 22 four-year-old eucalyptus clones in Guangxi, China. Results indic... The effectiveness of pilodyn was tested in evaluating wood basic density, outer wood density, heartwood density, and modulus of elasticity (MoE) at 22 four-year-old eucalyptus clones in Guangxi, China. Results indicated that the mean value ranged from 9.44 to 15.41 mm for Pilodyn penetration, 0.3514 to 0.4913 g.cm^-3 for wood basic density, and 3.94 to 7.53 Giga Pascal (GPa) for MoE, respectively. There were significant differences (1% level) in pilodyn penetration between different treatments, different directions and among the clones. Generally strongly negative correlations were found between pilodyn penetration and wood properties, and the coefficients ranged from -0,433 to -0,755. Our results, together with other studies, suggest that the use of pilodyn for assessing wood density and MoE was confirmed as a possibility. 展开更多
关键词 CORRELATION EUCALYPTUS modulus of elasticity PILODYN wood density
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Effects of Shading Treatments on Growth of Asimina triloba(L.) Dunal Seedlings
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作者 朱延林 黄建全 +4 位作者 张江涛 张娜 翟晓巧 王念 赵蓬辉 《Agricultural Science & Technology》 CAS 2007年第3期42-44,78,共4页
[Objective]The study was conducted to investigate the effects of shading treatments on growth of Asimina triloba (L) Dunal seedlings and provided the theoretical basis for seedling production. [Method]70 day-old A. ... [Objective]The study was conducted to investigate the effects of shading treatments on growth of Asimina triloba (L) Dunal seedlings and provided the theoretical basis for seedling production. [Method]70 day-old A. triloba seedlings had similar stem diameter and plant height and good growth vigour were taken as tested materials in 2005. 4 light gradient treatments which were the natural light with 100% light intensity, one-layer, two-layer and three-layer black shading network with the light transmittance rate of 50%, 25% and 12.5% were set up to study the effects of different shading treatments on growth of A. triloba. [ Result] With the shading treatments of one-layer and two-layer net, the plants of A. triloba seedlings grew rapidly. As the intensity of illumination decreased, the cetents of chlorophyll a ( Chl. a), chlorophyll b ( Chl. b) and total chlorophyll increased at first and then reduced. At the same time the chlorophyll a/b value became smaller. Under natural light, the plants tended to consume more water and the soil temperature at 15:00 p. m was higher. There was a smaller difference among various treatments. [ Conclusion]The suitable shading treatment to the growth of A. triloba seedlings was under the light transmittance rate of 50% and height and stem diameter of trees increased fast. Chlorophyll a ( Chl. a), chlorophyll b ( Chl. b) content in leaves of A. triloba seedlings were highest comparing with those in other conditions. 展开更多
关键词 Asimina triloba Shading treatment GROWTH Chlorophyll content
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A Systematic Study on the Genus Aphytis Howard (Hymenoptera:Aphelinidae) from South Korea 被引量:1
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作者 李成德 杨庆寅 《Entomotaxonomia》 CSCD 北大核心 2004年第4期307-312,共6页
The present paper deals with the systematic study on the genus Aphytis Howard from South Korea. Five species of Aphytis are recognized, including one new species (Aphytis albus sp. nov.) and four new records (A. diasp... The present paper deals with the systematic study on the genus Aphytis Howard from South Korea. Five species of Aphytis are recognized, including one new species (Aphytis albus sp. nov.) and four new records (A. diaspidis, A. japonicus, A. proclia and A. vandenboschi). A key to the female species of Aphytis from South Korea is provided. The type specimens are respectively deposited in Korea National Arboretum and the Insect Collection of Northeast Forestry University, Harbin, China. 展开更多
关键词 HYMENOPTERA APHELINIDAE Aphytis SYSTEMATICS South Korea
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Nursery Testing of Superior Tree Progeny of Cupressus funebris
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作者 谭小梅 周益权 周小舟 《Agricultural Science & Technology》 CAS 2014年第9期1562-1566,共5页
[Objective] Breeding and genetic improvement for Cupressus funebris was performed based on the extensive genetic variation among provenances and fami- lies. [Method] The two-year-old Cupressus funebris, from 4 provena... [Objective] Breeding and genetic improvement for Cupressus funebris was performed based on the extensive genetic variation among provenances and fami- lies. [Method] The two-year-old Cupressus funebris, from 4 provenances and 34 superior Cupressus funebris families introduced from Chongqing and Qiandao Lake of Zhejiang Province, was used as test material, and the differences in growth traits among provenances and families at the seedling stage of Cupressus funebris were investigated. [Result] The height and ground diameter of seedlings differed signifi- cantly among provenances and families. Their variation coefficients among families were 11.37% and 18.89%, and among provenances were 7.25% and 12.58% re- spectively. [Conclusion] There was relatively rich genetic variation in height and ground diameter among provenances and families of Cupressus funebris. It has a certain breeding potential. 展开更多
关键词 Cupressus funebris Superior tree Seedlinq trait FAMILY Early selection
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Variable chlorophyll fluorescence in response to water plus heat stress treatments in three coniferous tree seedlings 被引量:10
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作者 喻方圆 Robert D.Guy 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期24-28,J001-J002,共7页
Effects of water and heat stress treatments on chlorophyll fluorescence of Chinese fir (Cunninghamia lanceolata), Masson pine (Pinus massoniana) and western redcedar (Thuja plicata D. Don)_seedlings were monitored dur... Effects of water and heat stress treatments on chlorophyll fluorescence of Chinese fir (Cunninghamia lanceolata), Masson pine (Pinus massoniana) and western redcedar (Thuja plicata D. Don)_seedlings were monitored during a three-cycle stress period. It was shown that ratio of variable to maximal chlorophyll fluorescence (Fv/Fm) of these three species responded differently to water stress treatments. The Fv/Fm ratio of western redcedar decreased dramatically after water stress, while that of Chinese fir had only a slight reduction and that of Masson pine had no significant change. The experiment also showed that the Fv/Fm ratio of all three species differed significantly under heat stress treatments. Concerning three different water plus heat stress cycles, it was found that the Fv/Fm ratios of Chinese fir and Masson pine measured at the end of each water plus heat stress cycle were not significantly different. However, the Fv/Fm ratio of western redcedar was diminished significantly in response to an increase of stress time. Keywords Chinese fir - Chlorophyll fluorescence - Heat stress - Masson pine - Water stress - Western redcedar CLC number Q945.17 - S791.248 Document code A Biography: Yu Fang-yuan (1965-), male, Ph. Doctor. Associate professor in College of Forest Resources and Environment, Nanjing, Forestry University, Nanjing 210037, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Chinese fir Chlorophyll fluorescence Heat stress Masson pine Water stress Western redcedar
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Effect of water stress on N_2O emission rate of 5 tree species
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作者 王淼 李秋荣 +1 位作者 肖冬梅 王长科 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期19-23,J001,共6页
The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed ... The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed bag-gas chromatography. A total of five species seedlings were involved in this study, i.e.,Pinus koraiensis Sieb. et Zucc,Fraxinus mandshurica Rupr,Juglans mandshurica Maxim,Tilia amurensis Rupr, andQuercus mongolica Fisch. ex Turcz.. The results showed that the stomatal conductance, net photosynthetic rate and N2O emission of leaves were significantly reduced under the water stress. The stoma in the leaves of trees is the main pathway of N2O emission. N2O emission in the trees mainly occurred during daytime. N2O emission rates were different in various tree specie seedlings at the same water status. In the same tree species, N2O emission rates decreased as the reduction of soil water contents. At different soil water contents (MW, LW) the N2O emission rates ofPinus koraiensis decreased by 34.43% and 100.6% of those in normal water condition, respectively. In broadleaf arbor decreased by 31.93% and 86.35%, respectively. Under different water stresses N2O emission rates in five tree species such asPinus koraiensis, Fraxinus mandshurica, Juglans mandshurica, Tilia amurensis, andQuercus mongolica were 38.22, 14.44, 33.02, 16.48 and 32.33 ngN2O·g?1DW·h?1, respectively. Keywords Trees - N2O emission rate - Soil water stress - broadleaf/Korean pine forest - Changbai Mountain CLC number S718.55 Document code A Foundation item: This project was supported by the National Natural Science Foundation of China (No. 30271068), the grant of the Knowledge Innovation Program of Chinese Academy of Sciences (KZ-CX-SW-01-01B-10), and the Special Funds for Major State Basic Research Program of China (No. G1999043407)Biography: Wang Miao (1964-), male, associate professor in Institute of Applied Ecology, Chinese Academy of Science, Shenyang 110016, P. R. China.Responsible editor: Song Funan 展开更多
关键词 Trees N2O emission rate Soil water stress broadleaf/Korean pine forest Changbai Mountain
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Impact of ice-snow damage on nutrient distribution of a Cunninghamia lanceolata woodland
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作者 陈凤霞 冯慧芳 +3 位作者 薛立 潘澜 许鹏波 刘斌 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期207-212,I0006,I0007,共8页
During January to February in 2008,severe ice-snows occurred on 2.09×10^6 km^2 of south China and caused tremendous damage to the forests.Stem damage and crown debris input from the ice-snow in a Cunninghamia lan... During January to February in 2008,severe ice-snows occurred on 2.09×10^6 km^2 of south China and caused tremendous damage to the forests.Stem damage and crown debris input from the ice-snow in a Cunninghamia lanceolata stand in northern Guangdong Province,China,were investigated to determine the extent of ice-snow damage to trees and the nutrient distribution characteristics on woodland.Icicles were produced on branches and leaves of the C.lanceolata trees by sleets,resulting in all live trees were damaged by stem breakage.A strong positive correlation was found between the broken position of trees and diameter at breast height(DBH).Nutrient concentrations varied according to components of crown debris.Total nutrient concentration graded in the following order:leaves 〉stembark 〉branches 〉stemwood.Crown debris input from ice-snows was 19.11 t·ha^-2,and branches,stemwood,leaves and stembark accounted for 37%,28%,27% and 8%,respectively.Nutrient distributions between components of crown debris differed drastically in 2008.The contribution of leaves to total nutrient accumulation of crown debris was 70%,whereas branches,stemwood and stembark contributed 13%,7% and 10%,respectively.Accumulations of N,P and K by the woodland were 105 067.9 t·ha^-2 in 2008,and the nutrients of crown debris,litter and the stand soil accounted for 0.18%,0.03% and 99.79%,respectively.The order of nutrient accumulation in leaves,branches,stembark,stemwood of crown debris and litter was N〉K〉P,but the nutrients stored in the soil were in the order of K 〉N 〉P.The N and P concentrations of litter in 2009 were greater than those in 2008,whereas its K concentration was smaller than that of the latter.N and P concentrations of stemwood and stembark in 2009 were slightly greater than those in 2009,whereas their K concentration was smaller than the latter.The N and P accumulations of stemwood and stembark of crown debris in 2009 were close to those in 2008,whereas their K accumulation was slightly smaller than the latter.The N,P and K accumulations of litter in 2009 was greater than those in 2008. 展开更多
关键词 crown debris Cunninghamia lanceolata ice-snow damage LITTER nutrient soil
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从“树木而涂之”来看社鼠寄身何处
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作者 江山丽 《励耘语言学刊》 2011年第1期216-224,共9页
《韩非子·外储说右上》一文提到社鼠寄居之"社"的建造方式是"树木而涂之"。由于对建筑方式的陌生,人们对这句话无从理解,因而对于社鼠究竟寄身何处各作揣度,或曰社树、或曰社主、或曰社坛、或曰土地神像,争执无休;并在此基础... 《韩非子·外储说右上》一文提到社鼠寄居之"社"的建造方式是"树木而涂之"。由于对建筑方式的陌生,人们对这句话无从理解,因而对于社鼠究竟寄身何处各作揣度,或曰社树、或曰社主、或曰社坛、或曰土地神像,争执无休;并在此基础上对古代社文化作出种种推断,可谓一误再误。事实上,"树木而涂之"反映的是社墙建造之法,描述的是我国古代黄河流域十分普遍的一种建筑方式——木骨泥墙。而社鼠,正是寄居于社墙之中。 展开更多
关键词 树木而涂之 木骨泥墙 训诂
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Response of seedlings of different tree species to elevated CO_2 in Changbai Mountain 被引量:1
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作者 王淼 李秋荣 +1 位作者 代力民 姬兰柱 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期112-116,共5页
Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadlea... Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadleaved/Korean pine forest, to elevated CO2 were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998-1999). Two concentrations of CO2 were designed: elevated CO2 (700 祄olmol-1) and ambient CO2 (400 祄olmol-1). The study results showed that the height growth of the tree seedlings grown at elevated CO2 increased by about 10%-40% compared to those grown at ambient CO2. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO2 varied with tree species. The broad-leaf tree species were more sensitive to the elevated CO2 than conifer tree species. All seedlings showed a photosynthetic acclimation to long-term elevated CO2. 展开更多
关键词 Elevated CO_2 Eco-physiological response Changbai Mountain
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An Orthogonal Experiment of Papain-Assisted Extraction of Polysaccharides from Agrocybe aegirit
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作者 齐小琼 陈丽 《Agricultural Science & Technology》 CAS 2015年第10期2331-2333,2336,共4页
[Objective] This study aimed to explore optimum conditions for papain-as- sisted extraction of polysaccharides from Agrocybe aegirit. [Method] Because enzyme is capable of destroying organizational structure of cells,... [Objective] This study aimed to explore optimum conditions for papain-as- sisted extraction of polysaccharides from Agrocybe aegirit. [Method] Because enzyme is capable of destroying organizational structure of cells, papain was selected to cat- alyze cells to let polysaccharides out. An orthogonal experiment was carried out to investigate the effects of hydrolysis temperature, hydrolysis time, enzyme concentra- tion and solid to liquid ratio on extraction of polysaccharides from A. aegirit. [Result] Through the orthogonal experiment, the optimum papain-assisted extraction conditions were obtained: hydrolysis temperature, 45 ℃; hydrolysis time, 2 h; enzyme concen- tration 2%; solid to liquid ratio, 1:80. [Conclusion] This study will provide a reference for extraction of polysaccharides from A. aegirit. 展开更多
关键词 Agrocybe aegirit Papain Orthogonal experiment Polysaccharide extraction
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