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ANALYSIS OF COMPUTER VISION ON RESIN EFFICIENCY IN PARTICLEBOARD

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Journal of Northeast forestry University 1994年第1期5卷 76-81页

作者：卢跃斌王金满胡国民 1. Northeast forestry University China 2. weihe forestry bureau Heilongjiang Province China

This paper summarized the previous researches about resin emciency of particleboard in the world, and introduced the computer vision (CV) technique on resin effciency. which has the properties of high measuring speed, automatic pattern recognition and low environmental requirement. etc. The theory of the CV technique used for resin effciency in particleboard was studied,along with the handling of resined-particle images and the gathering of relative gray image features. Some quantitative parameters describing the resin efficiency of particleboard were established, and the results indicated that the computer vision method on the resin effciency was much better than others and can control the producing of pafticleboard more effect.

关键词： Particleboard Resin efficiency Computer vision

Spatial distribution of heavy metals(Cu, Pb, Zn, and Cd)in sediments of a coastal wetlands in eastern Fujian, China

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Journal of forestry Research 2015年第3期26卷 703-710页

作者： Lili Zhao Weibin You Haiqing Hu Wei Hong Xiaojuan LIAO Shihong Xiao Ren Wang Jinbiao Cai Xuncheng Fan Yong Tan Dongjin He Fujian Agriculture and forestry University Northeast forestry University forestry bureau of Fuding forestry bureau of Xiapu

We investigated the spatial distribution （horizontal and vertical concentrations） of copper （Cu）, lead （Pb）, zinc （Zn）, and cadmium （Cd） in five wetland types （mudflat, aquaculture wetland, water area, farmland wetland and mangrove） from three areas （Ningde, Fuding, and Xiapu）, China. Cu concentrations in five wetland types descended in the order： farm wetland, mudflat, aquaculture, water area and mangrove. Pb concentrations decreased in the order： aquaculture, mangrove, farm wetland, mudflat, and water area. Zn content decreased in the order： farm wetland, water area, aquaculture, mudflat and mangrove, and Cd content decreased as follows： mangrove, aquacul- ture, water area, rnudflat, and farm wetland. Comparison of the concentrations of the same heavy metals in different areas showed that the highest Cu （63.75 mg kg-1） and Zn （152.32mgkg-1） concentrations occurred in Ningdecoastal wetlands; Pb （110.58 mg kg-1） and Cd （2.81 mg kg-1） contents were highest in Fuding wetlands, and the average contents of all heavy metals were very low in Xiapu wetlands. Examination of the vertical distribution showed that the Cu content was high in all mudflat layers; Pb and Cd concentrations were highest in aquaculture and mangrove wetlands, respectively, and Zn content was highest in farm wetlands. The spatial distribution of Cu and Zn contents for different areas decreased as follows： Ningde 〉 Fuding 〉 Xiapu, for Pb and Cd were most concentrated in Fuding coastal wetlands. Concentrations of Zn and Cu were highly correlated, while Zn and Cu were not significantly correlated with Pb.

关键词： Coastal wetland Heavy metal Spatialdistribution Eastem Fujian Ningde City

Spatial distribution and dynamics of carbon storage in natural Larix gmelinii forest in Daxing'anling mountains of Inner Mongolia,northeastern China

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Journal of Mountain Science 2017年第8期14卷 1633-1641页

作者： MENG Sheng-wang LIU Qi-jing JIA Quan-quan ZHUANG Hui-xia QI Ying LU Cheng-xue DENG Liu-bao College of forestry Beijing Forestry University forestry Industry bureau of Inner Mongolia

In order to clarify the geographic distribution and change of natural Larix gmelinii forest in carbon storage in Daxing'anling mountains(Great Khingan Range) in North China's Inner Mongolia, an area-irrelevant conversion equation of biomass from timber volume in the form of B = 0.6966 V was developed by using survey data. Based on the equation, the carbon storage was estimated at 190.172 Tg, and the average carbon density was 41.659 Mg/hm^2(area 4.565 × 10~6 hm^2). Carbon stored in standing trees was predominantly distributed in mid-age and mature forests and mainly stocked in the northern part of the study area. Assuming the carbon density of intact area as the maximum value, the potential carbon storage in the entire study area would be 263.674 Tg, approximately 1.4 times of the actual level. Over the period of 1995 to 2010, the carbon storage and carbon densityincreased by 3.260 Tg and 0.224 Mg/hm^2, respectively, indicating a weak carbon sink. Comparing with China's national average level, the carbon density in this area is not as high as expected. Forest quality in terms of carbon capacity is expected to be enhanced by appropriate management schemes under the in-implementation program of forest protection.

关键词： Biomass conversion equation Carbonstorage Great Khingan Range Distribution Larixgmelinii

A male-specific SCAR DNA marker and sex ratio of seedlings in salak(Salacca zalacca ***)

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Journal of forestry Research 2017年第1期28卷 47-50页

作者： Rongsheng Li Jianguang Li Guangtian Yin Jinchang Yang Wentao Zou Lei Bai Research Institute of Tropical forestry Chinese Academy of Forestry forestry bureau of Huicheng District Huizhou City

A male-specific SCAR DNA marker was developed using a RAPD DNA marker specific for male plants of Salacca zalacca var. zalacca （salak palm）. The marker is 1579 bp long and has a GC content of 38.5 %. Its sequence contains 1 or 2 open reading frames, indicating the marker is probably a coding region. No highly similar sequences were found in a search of the GenBank database. Sexes were identified using the SCAR DNA marker for three kinds of seedlings grouped by the number of seeds per fruit （1, 2 or 3）. The sex ratio of female to male did not differ significantly from 1：1 for the three kinds of seedlings, implying that the number of seeds per fruit is not a reliable index to identify the sex of a seedling.

关键词： Salacca Salak SCAR. Sex

Genetic variation and selection of introduced provenances of Siberian Pine(Pinus sibirica) in frigid regions of the Greater Xing'an Range,Northeast China

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Journal of forestry Research 2014年第3期25卷 549-556页

作者： Xiyang Zhao Cheng Wang Shuchun Li Wei Hou Shiqing Zhang Guijie Han Deng Pan Ping Wang Yufei Cheng Guifeng Liu State Key Laboratory of Tree Genetics and Breeding (Northeast forestry University) Northeast Forestry University Tree Seedling Management Station Forestry Department of Jilin Province Department of Preventive Medicine Stony Brook University forestry bureau of Xinlin Agricultural bureau of Taobei District

Siberian Pine （Pinus sibirica） is an ecologically and eco-nomically important species in pristine forests throughout northern Rus-sia. Four provenances of P. sibirica were introduced from Mongolia and Russia to the Greater Xing’an Range （the Daxing’anling）, northeast China in 1993. The aim of this research was to study genetic variation and selection of the introduced four Pinus sibirica provenances. Heights （H）, basal diameters （BD）, survival rates （SR） and crown lengths （CL） of different families were measured as primary outcomes in different growth years. Results of data analyses demonstrated high coefficients of phenotypic variation （PCV） and heritability （H2） for H, BD and CL at 18 years after introduction. PCV and H2 increased with age. Correlations of＆amp;nbsp;growth traits between any two growth years were all significantly positive, but the correlation coefficient was smaller when the growth year interval was larger. Correlations between H and the original environment factors decreased gradually, indicating that with long-term subsistence in the new environment, the influence of the source environment declined. Colligation of multiple traits to estimate provenances showed that Novosibirsk, Tomsk, and Altai Mountains had higher survival rates and biomass, and proved more suitable for introduction and plantation in the Greater Xing’an Range in China.

关键词： Pinus sibirica provenance genetic testing variation selection

Comparative growth, dry matter accumulation and photosynthetic rate of seven species of Eucalypt in response to phosphorus supply

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Journal of forestry Research 2014年第2期25卷 377-383页

作者： Peng-fei Wu Xiang-qing Ma Mulualem Tigabu Yong Huang Li-li Zhou Liping Cai Xiao-long Hou Per Christer Oden forestry College Fujian Agriculture and Forestry University Swedish University of Agricultural Sciences Faculty of Forest ScienceSouthern Swedish forest Research Centre Ningde forestry bureau

Plantations of eucalypts as short-rotation tree crops are rapidly expanding in tropical and sub-tropical regions, including southern China, where the soils are acidic and available phosphorus （P） is limited. We investigated seedling growth, dry matter accumulation, and the dynamics of photosynthetic rate and chlorophyll content of seven Eucalyptus spe- cies/hybrids （E. dunnii, E. grandis, E. grandis x E. camaldulensis, E. urophylla x E. camaldulensis, E. urophylla x E. tereticornis, E. grandis x E. tereticornis, E. urophylla x E. grandis） in response to different levels of P supply （0, 6, 12 and 18 mg-kg-l KH2PO4）. The photosynthetic rate and the chlorophyll content significantly declined as the P supply declined in almost a linear fashion for all species as the P stress period extended. In the absence of P supply, height growth of seedlings of all species was significantly impaired, while root collar diameter growth and whole plant dry matter accumulation was not affected by the level of P supply in most of the species. Significant inter-species variations in growth, dry matter accumulation and photosynthetic rate in response to P supply were detected. Eucalyptus dunnii had the lowest growth perform- ance across all levels of P supply while E. urophylla x E. tereticornis showed superior growth performance. From a practical point of view, E. urophylla x E. tereticornis is suggested as a candidate hybrid for planting on slightly P-deficient sites in southern China while E. dunnii, being a slow-growing species, is not suitable for short-rotation plantation. On plantation sites where severe P deficiency exists, P fertilization needs to be considered to boost rapid growth of seedlings so as to meet the man- agement objectives of short-rotation plantation.

关键词： biomass Eucalyptus phosphorus stress pulp short-rotation forestry

Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement

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Journal of forestry Research 2024年第2期35卷 146-162页

作者： Yuanyuan Wang Xinzhu Dai Xingling Chen Dan Zhang Guiqing Lin Yuanhang Zhou Tianyi Wang Yulong Cui Academy of forestry Sciences of Changchun Bureau of Forestry and Landscaping of ChangchunChangchun 130117People’s Republic of China College of Landscape Architecture Changchun UniversityChangchun 130022People’s Republic of China Changchun South Lake Park Bureau of Forestry and Landscaping of ChangchunChangchun 130012People’s Republic of China

Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of *** clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density *** found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer *** conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus *** addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,*** findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.

关键词： Species diversity Forest characteristics Biomass carbon sink Forest-type effect Urbanization effect Urban forests

ASSESSMENT OF ANIMAL SKIDDING AND GROUND MACHINE SKIDDING UNDER MOUNTAIN CONDITIONS

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Journal of Northeast forestry University 1996年第1期7卷 63-72页

作者：王立海马富龙刘春山顾众业孙剑峰 Northeast forestry University Harbin China forestry bureau of Shuangyashan Heilongjiang Province forestry bureau of Hanjiayuan Heilongjiang Province

The Proportion of animal skidding in forest operations in Heilongjiang forest region increased signiticantly in recent years. This paper at first demonstrated and analyzed the development of the animal skidding and machine skidding, then, evaluated these two means of *** currently runing in this region both individually and comprehensively under the following criteria: operation efficiency or operation cost, degree of damage to soil and residual stands, accident rate, and natural regeneration. Finally, according to the results of synthetic assessments, cIassitications of operation conditions suitable to each of skidding measures were recommended quqntitatively with considerations of multiple evaluation criteria.

关键词： Animal skidding Ground machine skidding Multiple criteria Classification of operation conditions

EFFECT OF FERTILIZATION ON THE GROWTH OF LARCH SEEDLINGS

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Journal of Northeast forestry University 1991年第1期2卷 37-41页

作者： Liu Yongchun Chen WenbinNortheast forestry UniversityLi JichengDailing Experimental forestry bureau of Hcilongjiang ProvinceLi HuachenTahe forestry bureau of Heilongjiang Province 1. Northeast forestry University China 2. Dailing Experimental forestry bureau of Heilongjiang Province China 3. Tahe forestry bureau of Heilongjiang Province China

The primary purpose of fertilization in nursery soils is to assure production of high-quality planting stock. Therefore, the appropriate information on fertilizers and their use as well as their effects on seedling growth is important to nursery managers in their nursery practice. In this paper, larch seedling growth response to six fertilizers are discussed based on the results of three-year studies which were carried out at Dailing Forest Nursery in 1987.

关键词： Fertilization Larch Growth of seedling