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Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

Science China(Technological Sciences) 2006年第Z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui Institute of Applied Ecology, Chinese academy of Sciences, Shenyang 110016, China School of Forestry, Northeast Forestry University, Harbin 150040, China State Key Lab of Systems Ecology, Research Center for Eco-Environmental Sciences, Chinese academy of Sciences, Beijing 100085, China Graduate University of Chinese academy of Sciences, Beijing 100039, China Institute of Applied Ecology Chinese Academy of Sciences Shenyang China School of Forestry Northeast Forestry University Harbin China State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of Sciences Beijing China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of China (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was44.2%, much lower than those for Larix forest (the RMSE was 51.7%) and those for the korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

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Suspension Culture and Somatic Embryogenesis of korean Pine

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Phyton-International Journal of Experimental Botany 2022年第1期91卷 223-238页

作者： Chunxue Peng Fang Gao Hao Wang Iraida Nikolaevna Tretyakova Alexander Mikhaylovich Nosov Hailong Shen Ling Yang State Key Laboratory of Tree Genetics and Breeding School of ForestryNortheast Forestry UniversityHarbin150040China State Forestry and Grassland Administration Engineering Technology Research Center of korean Pine Harbin150040China Laboratory of Forest Genetics and Breeding Institution of the Russian Academy of SciencesV.N.Sukachev Institute of Forest Siberian Branch of RASKrasnoyarsk660036Russia Department of Cell Biology and Institute of Plant Physiology K.A.Timiryazev Russian Academy of SciencesMoscow127276Russia Department of Plant Physiology Biological FacultyLomonosov Moscow State UniversityMoscow119991Russia

korean pine is an important afforestation tree species in Northeast China,which has a high ecological and economic *** regeneration of somatic embryogenesis using immature zygotic embryos of korean pine as explants has been successful,it cannot be applied to automation and large-scale ***,we urgently need a method that can increase the output of somatic embryos(SEs)to meet the needs of large-scale *** used korean pine 1-1 and 1-100 cell lines as research materials to evaluate the effects of inoculum-density,culture time,orbiting speed,vessel volume,plant growth regulator(PGR)concentration,and carbon source on the proliferation of embryogenic tissue(ET).The somatic embryogenesis ability of ET cultured in different liquid suspension media was also *** found that during liquid suspension culture of korean pine ET,the sedimented cell volume(SCV),fresh weight(FW)and dry weight(DW)were affected by inoculumdensity,culture time,orbiting speed,2,4-D concentration,6-BA concentration and carbon source *** mg⋅mL^(−1)ET were transferred to a 200 mL Erlenmeyer flask containing 20 mL liquid medium,and cultured at 100 rpm/min for 14 days to obtain the maximum *** addition,we also found that SCV,FW and DW were higher when PGRs were reduced in the liquid suspension *** substitution of maltose for sucrose resulted in slow growth of cultures and limited SE yield(13 SEs g^(−1)FW).Although culture proliferation was high at 50 rpm,SE yield was inhibited by 48%compared with 100 rpm(50 rpm=33 SEs g^(−1)FW;100 rpm/min=70 SEs g^(−1)FW).Cultivation in low-concentration PGR(1.15μM⋅L^(−1)2,4-D,0.25μM⋅L^(−1)6-BA)and sucrose liquid medium at 100 rpm/min(80 SEs g^(−1)FW)could not only promote culture proliferation but also increase SE *** determination of the suspension culture scheme of korean pine ET provides a reference for further expansion to bioreactor culture in the future and lays a foundation for the automatio

关键词： Pinus koraiensis Sieb.et Zucc embryogenic tissue liquid suspension medium cell proliferation

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Discovery of the Changtu Fauna in the Xia' ertai and Hulan Groups in Liaoning and Jilin and Its Significance

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Acta Geologica Sinica(English Edition) 1992年第4期66卷 427-438,445-447页

作者： Liu Xiaoliang Chen Congyun Yang Xuezeng Yang Sen Zhang Jiongfei Gao Yuhua Shenyang Institute of Geology and Mineral Resources, Chinese academy of Geological Sciences, Shenyang, Liaoning Sun Sheping Shenyang Institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Shenyang Liaoning

The Ordovician Changtu Fauna is recently discovered in the Xia' ertai and Hulan Groups in northernLiaoning-central Jilin. The fauna, containing 10 genera and 14 species (including 3 new genera, 9 new speciesand an unidentified species), is closely related in evolution with the Early Cambrian Qinghezhen Fauna. Thediscovery of this fauna is significant to the study on the age of the strata, Ordovician biostratigraphy and geo-logical evolution of the tectonostratigraphical terrane on the northern margin of the Sino-korean plate.

关键词： Northern Liaoning-central Jilin Ordovician Changtu Fauna

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On the origin of printing in the light of new archaeological discoveries

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Chinese Science Bulletin 1997年第12期42卷 976-981页

作者： PAN JixingInstitute for History of Natoral Science, Chinese academy of Sciences, Beijing 100010, China Institute for Histoty of Natoral Science Chinese Academy of Sciences Beijing China

30 years have passed since a printed dharani sutra scroll was discovered in 1966 in Kyongju, Korea. However, there have been different views about the date and place of its printing and publication in Korea and abroad. Some korean scholars think that it was translated into Chinese from Sanskrit in 704 in China and printed during 706-751 in the Silla period in Korea. After a further research it is now proved that this sutra was translated into Chinese in 701 and printed in the follow-ing year, 702, in Luoyang, during the reign of Empress Wu. This shows that the sutra could not have been printed in the Silla period. The discoveries of the Saddharma pundarik sutra printed during 690-699 and the Sanskrit dharani charm printed around 650-670 in China also show that the dharani sutra found in Korea is not the earliest one. Both literary records and archaeological findings prove that printing originated in China.

关键词： origin printing China dharani sutra

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Effects of Logging Intensity on Structure and Composition of a Broadleaf-korean Pine Mixed Forest on Changbai Mountains,Northeast China

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Chinese Geographical Science 2016年第1期26卷 59-67页

作者： WU Zhijun SU Dongkai NIU Lijun Bernard Joseph LEWIS YU Dapao ZHOU Li ZHOU Wangming WU Shengnan DAI Limin State Key Laboratory of Forest and Soil Ecology Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Liaoning Technical University Fuxin 123000China University of Chinese academy of Sciences Beijing 100049China Jilin Forest Industry Group Limited Liability Company Changchun 130021China Changbai Mountains academy of Sciences Antu 133613China

In order to identify a harvesting model which is beneficial for broadleaf-korean pine mixed forest （BKF） sustainability, we investigated four types of harvested stands which have been logged with intensities of 0 （T0, control）, 15% （T1, low intensity）, 35% （T2, moderate intensity）, and 100% （T3, clear-cutting）, and examined the impacts of logging intensity on composition and structure of these stands. Results showed that there were no significant differences between To and T1 for all structural characteristics, except for density of seeding and large trees. The mean diameter at breast height （DBH, 1.3 m above the ground）, stem density and basal area of large trees in T2 were significantly lower than in To, while the density of seedlings and saplings were significantly higher in T2 than in To. Structural characteristics in T3 were entirely different from To. Dominant tree species in primary BKF comprised 93%, 85%, 45% and 10% of the total basal area in T0, T1, T2 and T3, respectively. Three community similarity indices, the Jaccard＇s similarity coefficient （Cj）; the Morisita-Hom index （CMH）; and the Bray-Curtis index （CN）, were the highest for T0 and T1, followed by T0 and T2, and T0 and T3, in generally. These results suggest that effects of harvesting on forest composition and structure are related to logging intensities. Low intensity harvesting is conductive to preserving forest structure and composition, allowing it to recover in a short time period. The regime characterized by low logging intensity and short rotations appears to be a sustainable harvesting method for BKF on the Changbai Mountains.

关键词： broadleaf-korean pine mixed forest forest structure species composition logging intensity Changbai Mountains

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Variation in Summer Rainfall in North China during the Period 1956-2007 and Links with Atmospheric Circulation

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Advances in Atmospheric Sciences 2011年第2期28卷 363-374页

作者：梁丰陶诗言卫捷布和朝鲁 Beijing Meteorological Bureau China Meteorological Administration Institute of Atmospheric Physics Chinese Academy of Sciences

Using gauge precipitation data and NCEP-NCAR reanalysis data, the interdecadal changes in summer precipitation during the period 1956-2007 in North China and the link with atmospheric circulation change over Eurasia are studied. Results show that precipitation amounts decreased by 16.2 mm per decade, which was attributable to a significant reduction in precipitation frequency. Contrary wave trains were found in the subtropical westerly jet （wave guide） over Eurasia for the wet and dry years of North China. When the wave trains had a ridge （trough） around the korean Peninsula, conditions favored （disfavored） the westward and northward extension of the West Pacific subtropical high. The westward and northward extension of the West Pacific subtropical high is, and was, beneficial to rainfall in North China. The downstream propagation of Rossby waves was found to favor the maintenance of these wave trains. Sensible heating in the south of Lake Baikal and latent heating from the korean Peninsula to the south of Japan increased during the period 1980-2007, as compared to that during 1957-1979. the wet period. These changes had positive influences on the maintenance of Anticyclonic-Cyclonic anomaly centers in the wave trains. Furthermore, northerly winds were prevalent in the lower troposphere during the dry period （1980-2007）. which prohibited the transportation of water vapor to North China from the seas and thereby led to a decrease in rainfall in North China. The weakening of the Indian Monsoon during the dry period might be one of reasons for the reduction in water vapor transportation.

关键词： North China precipitation frequency wave trains downstream development water vapor transportation latent heat sensible heat

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Present-day Slip-rate of Altyn Tagh Fault: Numerical Result Constrained by GPS Data

Present-day Slip-rate of Altyn Tagh Fault: Numerical Result ...

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作者： Pil-Ho PARK Houtze HSU Uk HAN GPS Research Group Korea Astronomy ObservatoryDaejeon 305-348South Korea Institute of Geodesy and Geophysics Chinese Academy of SciencesWuhan 430077China Department of Environmental Sciences Korean Military AcademySeoul 139-799South Korea

Geological and seismic evidence suggests that nearly two thirds of the convergence between India and Eurasia is accommodated by the crustal deformation of Asia. Two competing mechanisms were proposed to describe this accommodation: distributed crustal thickening and lateral extrusion along main faults. The kinematics of the Altyn Tagh Fault (ATF) is critical in determining the relative importance of these two mechanisms, inasmuch as the ATF slip-rates predicted by models of these competing mechanisms are very different. Using a finite element formalism to construct a thin-sheet model, we seek a velocity solution approaching the current kinematics of the ATF. The GPS data in the Tibetan Plateau and neighboring regions are employed as constraint conditions, in successive steps. The predicted velocity distribution near the ATF fits well to the observations, with overall standard deviations of 2.3mm/yr and 2.8mm/yr for the northward and eastward components, respectively. The inferred average slip-rate of the ATF is (7.4 ±1) mm/yr, with some variation along the fault. The slip-rate estimate of the ATF reported in this paper supports the distributed crustal thickening model for the crustal deformation of the Tibetan Plateau.

关键词： Slip-rate Altyn Tagh Fault GPS observations Numerical simulation

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Prediction of the globally ecological suitability of Panax quinquefolius by the geographic information system for global medicinal plants(GMPGIS)

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Chinese Journal of Natural Medicines 2019年第7期17卷 481-489页

作者： SHEN Liang LI Xi-Wen MENG Xiang-Xiao WU Jie TANG Huan HUANG Lin-Fang XIAO Shui-Ming XU Jiang CHEN Shi-Lin Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing 100700 China Institute of Medicinal Plant Development (IMPLAD) Chinese Academy of Medical Sciences (CAMS) Peking Union Medical College (PUMC) Beijing 100193 China

American ginseng(Panax quinquefolius L.) is a well-known Asian traditional herbal medicine with a large market demand. The plant is native to eastern North America, and its main producing areas worldwide are decreasing due to continuous cropping obstacles and environmental changes. Therefore, the identification of maximum similarities of new ecological distribution of ***, and prediction of its response to climate change in the future are necessary for plant introduction and cultivation. In this study, the areas with potential ecological suitability for P. quinquefolius were predicted using the geographic information system for global medicinal plants(GMPGIS) based on 476 occurrence points and 19 bioclimatic variables. The results indicate that the new ecologically suitable areas for P. quinquefolius are East Asia and the mid-eastern Europe, which are mainly distributed in China, Russia, Japan, Ukraine, Belarus, North korean, South Korea, and Romania. Under global climate change scenarios, the suitable planting areas for P. quinquefolius would be increased by 9.16%–30.97%, and expanding north and west over the current ecologically suitable areas by 2070. The potential increased areas that are ecologically suitable include northern Canada, Eastern Europe, and the Lesser Khingan Mountains of China, and reduced regions are mainly in central China, the southern U.S., and southern Europe. Jackknife tests indicate that the precipitation of the warmest quarter was the important climatic factor controlling the distribution of P. *** findings can be used as a useful guide for P. quinquefolius introduction and cultivation in ecologically suitable areas.

关键词： American ginseng Panax quinquefolius Ecological suitable area Climate change GMPGIS Jackknife test

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Synergistic effects between Suilllus luteus and Trichoderma virens on growth of korean spruce seedlings and drought resistance of Scotch pine seedlings

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Journal of Forestry Research 2016年第1期27卷 193-201页

作者： Dachuan Yin Xun Deng Ruiqing Song Northeast Forestry University Harbin China Forestry Protection Institute Heilongjiang Academy of Forestry Harbin China

korean spruce （Picea koraiensis Sieb. E1 Zucc.） is one of the main afforestation species in northern China. Seedling quality is a critical factor at planting time. To test whether the synergistic growth enhancement of Scotch pine （P. sylvestris var. mongolica） seedlings brought by the plant beneficial fungus Trichoderma virens （J.H. Mill., Giddens and A.A. Foster） Arx and ectomycorrhizal fungus （Suillus luteus （L.） Roussel.） can also benefit korean spruce seed- lings, we examined the effects of S. luteus and T. virens on the growth of P. koraiensis seedlings and drought resistance of P. sylvestris var. mongolica in peat soils. The two fungi were added to sterilized peat soil in pots, and the plants were grown for 4 months. Seedling growth and physiological variables, including mycorrhizal colonization rate of roots, biomass, and chlorophyll content, were examined. The colonization rate of the mycorrhizal fungus on P. koraiensis exceeded 65 %, and the synergism between S. luteus and T. virens enhanced most of the variables for P. koraiensis seedlings after inoculation with S. luteus then 30 days later with T. virens as in our published results for seedlings of P. sylvestris var. mongolica. When seedlings of P. sylvestris var. mongolica were inoculated with this sequence, they became more drought tolerant. T. virens also induced S. luteus to produce -l,3-glucanase and chitinase. This inocu- lation sequence at planting can thus improve the quality of P. sylvestris var. mongolica and P. koraiensis seedlings and substantiates our previous results.

关键词： Drought tolerance Growth enhancement Suillus luteus Synergistic interaction Trichoderma virens

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Pulling Vs. Pushing:Effect of Climatic Factors on Periodical Fluctuation of Russian and South korean Tourist Demand in Hainan Island,China

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Chinese Geographical Science 2017年第4期27卷 648-659页

作者： CHEN Fan LIU Jun GE Quansheng Tourism School Sichuan University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

While climate is an important factor attracting tourists to certain destinations,it can also motivate people residing in a country with a harsh climate to move to another *** applying X-12 decompositions and a panel data regression analysis,this study analyzes the pull and push effects of climatic seasonal factors between destination(Hainan Island,China) and source countries(Russia and South Korea).The findings show that climatic seasonal factors have significant pulling and pushing effects on seasonal patterns of tourism demand,with temperature being the main ***,the number of paid vacation days in the source country affects that country's sensitivity to climatic seasonal factors;countries with a higher numbers of paid vacation days are more sensitive to climatic ***,future global warming may causes the aforementioned pull and push effects to abate,which will have an unavoidable influence on tourism industries.

关键词： seasonality climate tourism demand Hainan Island China

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