oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 28 )

2018 ( 381 )

2017 ( 375 )

2016 ( 340 )

Custom range...

Search Results: 1 - 10 of 23609 matches for " GU Jia-cun "
All listed articles are free for downloading (OA Articles)
Page 1 /23609
Display every page Item
Effects of harvesting on spatial heterogeneity of soil moisture in secondary forests of Maoershan region
采伐干扰对帽儿山天然次生林土壤表层水分空间异质性的影响

GU Jia-Cun,
谷加存

生态学报 , 2005,
Abstract: The spatial and temporal variability in soil moisture is affected by a variety of factors, such as topography, climate, vegetation, soil properties, etc. Harvesting is one of important sources resulting in spatial heterogeneity in soil moisture. However, effects of harvesting on spatial heterogeneity in soil moisture were not clear. Here, we used geostatistics approach to quantify spatial heterogeneity in soil moisture caused by harvesting. Our objectives were to (1) examine how harvesting affected variatio...
THE EFFECTS OF SPATIAL HETEROGENEITY OF UNDERSTOREY LIGHT AVAILABILITY ON REGENERATION OF MANCHURIAN ASH
林分光照空间异质性对水曲柳更新的影响

HAN You-Zhi,WANG Zheng-Quan,GU Jia-Cun,
韩有志
,王政权,谷加存

植物生态学报 , 2004,
Abstract: 光照是森林更新动态中极为关键的环境因子.本研究在东北天然次生林中选择样地,应用地统计学理论结合实验生态学方法,定量分析林分光照空间异质性特征,同时进行林下播种水曲柳(Fraxinus s mandshurica)的更新实验,探测更新格局特征.通过空间关联性分析,研究探讨是否林分光照的空间变异对水曲柳更新有重要影响作用.研究结果表明:1)生长季林分平均光照仅为全光照的4.2%~4.6%,在空间分布上呈现非常明显的异质性特征,空间自相关变异(62.5%~78.2%)主要体现在10.9~12.4 m的尺度上.2)林分光照不同的空间样点上,水曲柳更新幼苗发生数量和秋季幼苗存活数量均存在显著差异,光照相对强的微生境中,更新苗发生数量较多且存活率高,而在光照较弱的微生境中则更新较差,更新具有十分明显的空间格局.3)更新格局与林分光照空间异质性特征紧密关联.在光照空间异质性程度较高、空间变异较复杂的条件下,更新相应呈现出较复杂的空间格局,自相关的变异表现在较小尺度范围(2.12~6.97m).在光照空间异质性程度较低、空间变异复杂性较小的条件下,更新格局的复杂程度明显变小,空间自相关变异(>83%)表现在较大的尺度上(30m),对更新格局起主要的影响作用,随机变异的影响很小(<17%).这些研究结果说明,林分光照环境在水曲柳更新中的作用十分关键,林分光照的空间异质性对更新格局起决定性作用.
Effects of nitrogen fertilization on ectomycorrhizal infection of first order roots and root morphology of Larix gmelinii plantation
施用氮肥对落叶松人工林一级根外生菌根侵染及形态的影响

SUN Yue,QUAN Xian-kui,JIA Shu-xia,GU Jia-cun,GUO Da-li,WANG Zheng-quan,
孙玥
,全先奎,贾淑霞,谷加存,郭大立,王政权

应用生态学报 , 2007,
Abstract: In this paper, the first order roots of Larix gmelinii plantation under N fertilization were sampled from different soil depths in different seasons to study their morphology under effects of ectomycorrhizal fungi. The results showed that the infection rate of ectomycorrhizal fungi on the first order roots was significantly affected by soil N availability, soil depth, and season. N fertilization induced a decrease of the infection rate, and the decrement varied with soil depth and season. In comparing with the control, the infected first order roots had an obvious variation of their morphology, e.g., averagely, root diameter increased by 18.7%, root length decreased by 23.7%, and specific root length decreased by 16.3%, which differed significantly with N application rate, soil depth, and season. The infection of ectomycorrhizal fungi changed the first order root morphology of L. gmelinii, which might substantially affect the physiological and ecological processes of host plant fine roots.
Effects of nitrogen fertilization on fine root biomass and morphology of Fraxinus mandshu-rica and Larix gmelinii: A study with in-growth core approach
内生长法研究施氮肥对水曲柳和落叶松细根生物量和形态的影响

LIU Jin-liang,MEI Li,GU Jia-cun,QUAN Xian-kui,WANG Zheng-quan,
刘金梁
,梅莉,谷加存,全先奎,王政权

生态学杂志 , 2009,
Abstract: 细根生物量是森林生态系统碳循环的重要组成部分,而细根形态影响细根吸收功能,这2个因子均受土壤资源有效性的影响。本文采用内生长法和施肥试验于2003—2004年对东北林业大学帽儿山试验林场17年生水曲柳(Fraxinus mandshurica)和落叶松(Larix gmelinii)人工林细根取样,区别不同根序,研究施氮肥对这2个树种细根生物量、形态和组织氮浓度的影响。结果表明:施氮肥显著降低了水曲柳和落叶松1~3级根的生物量、水曲柳2~4级根和落叶松3级根直径,以及水曲柳1~4级根和落叶松1级根的比根长(P<0.05),但是对根长影响不显著;施肥仅对水曲柳1~2级根组织中氮浓度增加显著(P<0.05)。这些研究对认识水曲柳和落叶松细根生理生态过程与土壤资源有效性的关系具有重要意义。
FINE ROOT MORPHOLOGY OF TWENTY HARDWOOD SPECIES IN MAOERSHAN NATURAL SECONDARY FOREST IN NORTHEASTERN CHINA
帽儿山天然次生林20个阔叶树种细根形态

SHI Wei,WANG Zheng-Quan,LIU Jin-Liang,GU Jia-Cun,GUO Da-Li,
师伟
,王政权,刘金梁,谷加存,郭大立

植物生态学报 , 2008,
Abstract: Aims We studied root morphology across the first five branch orders of 20 hardwood tree species from secondary forest in northeastern China. Our objectives were to determine how root morphology changes across root branch orders and how such variations of root morphology differ between ectomy-corrhizae (EM)-dominated and arbuscular mycorrhizae (AM)-dominated fine roots. Methods The fine roots were sampled in secondary forest in August 2006. We chose a random location in a plot under a randomly chosen individual tree and used a shovel to remove six soil blocks, 20 cm×20 cm×10 cm depth, from which the intact root segments were collected and placed in a Whirl-pac bag on ice in a cooler and then transported to the lab and frozen for dissection at a later date. In the laboratory, we dissected each individual root by branching order beginning with the distal end of a root system. After the dissection, we verified the type of mycorrhizal infection by staining and direct microscopic observation and determined diameter, length, and specific root length (SRL) of a given order. Important findings Root diameter and length increased, and SRL decreased from the first to fifth order roots, except in Ulmus pumila, Acer ginnala, Alnus sibirica, A. mandshurica and U. laciniata, in which first order roots had larger (or equal) diameter and lower SRL compared to second order roots. The first three order roots accounted for 80% of the total length, suggesting that lower order roots would have similar physiological functions despite their differences in morphology. Eleven species were EM, and nine were AM. Average diameter, length and SRL of each root order were larger for AM than EM species.
VARIATIONS OF FINE ROOT DIAMETER WITH ROOT ORDER IN MANCHURIAN ASH AND DAHURIAN LARCH PLANTATIONS
水曲柳和落叶松不同根序之间细根直径的变异研究

WANG Xiang-Rong,WANG Zheng-Quan,HAN You-Zhi,GU Jia-Cun,GUO Da-Li,MEI Li,
王向荣 王政权韩有志
, 谷加存 郭大立 梅 莉

植物生态学报 , 2005,
Abstract: 细根直径大小和根序高低对细根寿命和周转估计具有重要的影响,研究不同根序之间的直径变异对认识细根直径与根序的关系具有重要意义.该文根据Pregitzer等(2002)提供的方法,研究了位于东北林业大学帽儿山实验林场尖砬沟森林培育实验站17年生水曲柳(Fraxinus mandshurica)和落叶松(Larix gmelinii)人工林细根1~5级根序的平均直径的变化、直径的最小值和最大值范围、直径的变异系数.结果表明,水曲柳和落叶松细根直径<2mm时,包含5个根序,随着根序由小到大的增加,细根直径也在增大.各根序平均直径之间,存在较大的差异.在同一根序内,细根直径范围很大,水曲柳和落叶松一级根最小直径均<0.20mm,最大直径分别<0.50 mm(水曲柳)和<0.70mm(落叶松)左右.2~3级根序直径最小值在0.20~0.30 mm之间,最大值≤1.0mm.5级根直径最小值<1.0 mm,最大值超过2.0 mm.随着根序等级增加,直径变异系数增大.一级根序的直径平均变异系数<10%,2~3级根序直径平均变异系数在10%~15%左右,4~5级根序直径的平均变异系数在20%~30%之间.因此,在细根寿命与周转研究过程中,必须同时考虑直径和根序对细根的寿命估计的影响.
Fine root morphology, anatomy and tissue nitrogen and carbon contents of the first five orders in four tropical hardwood species in Hainan Island, China
海南岛4个热带阔叶树种前5级细根的形态、解剖结构和组织碳氮含量

XU Yang,GU Jia-Cun,DONG Xue-Yun,LIU Ying,WANG Zheng-Quan,
许旸
,谷加存,董雪云,刘颖,王政权

植物生态学报 , 2011,
Abstract: Aims Knowledge of fine root morphology, anatomy and tissue chemistry is critical to understanding root functions (e.g., longevity), but little is known about these root traits and their relationships in woody plants. We investigated root morphology, anatomy and tissue chemistry of the first five orders in four tropical tree species (Altingia obovata, Cryptocarya chinensis, Elaeocarpus sylvestris and Endospermum chinense) in Jianfengling of Hainan Island, China. Our objectives were to: 1) examine how root morphology (diameter, length, specific root length (SRL) and tissue density), anatomy (cortex thickness and stele to root diameter ratio (V/R)) and tissue chemistry (N and C content) changes with root branch orders and 2) reveal the relationships between anatomical structures and root diameter or tissue N or C concentrations in the four tree species. Methods Tree roots of the four species were sampled in August 2009, and root samples were sorted into different orders. Root morphology of the first five orders was analyzed by the Win-RHIZO system. Root tissue C and N concentrations in roots of each order were analyzed by the Vario MACRO Element Analyzer. Individual roots in each order were made into paraffin slices stained by safranin and fast green to observe root anatomical structures and to calculate cortical thickness, stele diameter and V/R. Important findings From the first to fifth order, root diameter, length and tissue density as well as stele diameter and V/R increased, and SRL and cortex thickness decreased in all species. The first two or three orders exhibited primary development with an intact cortex and lower V/R ratio, whereas higher order roots showed secondary development with no cortex and higher V/R ratio. Correlation analysis indicated that cortex thickness can explain 97% of the variations of root diameter and 70% of stele diameter. In all species, tissue N concentration decreased and tissue C concentrations increased with ascending root order. Moreover, C/N ratio in roots was mainly affected by tissue N rather than tissue C concentrations. These results suggest that there are systematic differences in root morphology, anatomy and tissue chemistry among different orders, and root morphology and tissue chemistry are closely linked to root anatomical traits such as cortex thickness in these tropical tree species.
EFFECT OF NITROGEN FERTILIZATION ON SOIL RESPIRATION IN LARIX GMELINII AND FRAXINUS MANDSHURICA PLANTATIONS IN CHINA
施肥对落叶松和水曲柳人工林土壤呼吸的影响

JIA Shu-Xia,WANG Zheng-Quan,MEI Li,SUN Yue,QUAN Xian-Kui,SHI Jian-Wei,YU Shui-Qiang,SUN Hai-Long,GU Jia-Cun,
贾淑霞
,王政权,梅莉,孙玥,全先奎,史建伟,于水强,孙海龙,谷加存

植物生态学报 , 2007,
Abstract: 以落叶松(Larix gmelinii)和水曲柳(Fraxinus mandshurica)人工林为研究对象,采用动态气室法(LI-6400-09叶室连接到LI-6400便携式CO2/H2O分析系统)对两种林分的土壤呼吸速率进行了观测,探讨了细根生物量、根中氮含量与土壤呼吸速率的关系,以及施肥对细根生物量、根中氮含量和土壤呼吸速率的影响。结果表明:1)施肥导致落叶松和水曲柳林分的活细根生物量降低18.4%和27.4%,死细根生物量分别降低了34.8%和127.4%;2)施肥使落叶松和水曲柳林地土壤呼吸速率与对照相比分别减少了34.9%和25.8%;3)施肥对根中氮含量没有显著影响;4)落叶松和水曲柳林地的土壤呼吸与土壤温度表现出相同的季节变化,两种林分的土壤呼吸速率与地下5和10cm处的温度表现出明显的指数关系,其相关性R2=0.93~0.98。土壤呼吸温度系数Q10的范围在2.45~3.29。施肥处理对Q10没有产生影响,施肥处理导致细根生物量减少可能是引起林地土壤呼吸速率下降的主要原因。
Remote Sensing Studies on Active Faults in the Western South-North Water Transfer Project Area in China
南水北调西线工程区活动断裂构造遥感研究

WEI Yong-ming,LIN Qi-zhong,WANG Xue-chao,WEI Cheng-jie,LI Jia-cun,
魏永明
,蔺启忠,王学潮,魏成阶,李家存

遥感学报 , 2005,
Abstract: According to the interpretation marks of active faults,about 200 faults were interpreted,which strike northwest, northeast, south-north and east-west respectively. Northwest-trending faults have the largest scale and regional feature, controlling the development of landforms and water systems in the Project Area. Among them, 22 faults have relatively larger effects on water transfer project. Through the field observation, it has been shown that there are 5 active faults in Holecene and 12 huge active faults in later Quaternary. However, it has been discovered by synthetical analyses that these active faults don't have critical threat on the water transfer project because of long distance from the water transfer project or not passing through it or other factors. In summary, the water transfer project will be stable relatively through active faults analysis.
null
不完备样本条件下基于支持向量回归模型的滑坡易发性评价

HU De-yong,ZHAO Wen-ji,LI Xiao-juan,LI Jing,LI Jia-cun,
胡德勇
,赵文吉,李小娟,李京,李家存

地理研究 , 2008,
Abstract: Landslide hazard susceptibility relates to middle-and long-term predicting and forecasting,and it is very important to landslide managements.In the process of evaluation based on statistical model,the result is greatly influenced by landslide sample size,so the more conservative and less influencing model must be applied to the susceptibility evaluation in order to reduce the system error.The study area is located in Malaysia tropical rainforest,where nine factors were selected as topographic slope,aspect,surface curvature,geomorphology,lithology,structure,land cover,road and drainage and so on.The Landslide Hazard Susceptibility Index(LSI) was constructed based on support vector regression(SVR) theory,then the susceptibility evaluation methodology was discussed in incomplete sample conditions,and the relation between the sample size and the result accuracy was analysed too.The result show that the success-rate analysis accuracy based on SVR model was about 95.9%,an obviously high value;the fluctuation of sample size influenced the accuracy slightly;SVR was a better model suited to landslide hazard evaluation in high vegetation cover conditions,which could provide a technique support for landslide management in similar areas.
Page 1 /23609
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.