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

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

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Carbon,nitrogen and phosphorus stoichiometry in Pinus tabulaeformis forest ecosystems in warm temperate Shanxi Province,north China

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Journal of forestry Research 2018年第6期29卷 1665-1673页

作者： Ning Wang Fengzhen Fu Baitian Wang Ruijun Wang College of Agronomy Heilongjiang Bayi Agricultural UniversityDaqing 163319HeilongjiangPeople’s Republic of China daqing forestry bureau Daqing 163002HeilongjiangPeople’s Republic of China Soil and Water Conservation School Beijing Forestry UniversityBeijing 100083People’s Republic of China

Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued.

关键词： Pinus tabulaeformis Carr. Forest ecosystem Content of carbon Nitrogen and phosphorus Ecological stoichiometry Warm temperate zone China

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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

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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

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TYPE AND EVOLUTION MODEL OF CONTINENTAL KEROGEN IN THE SONGLIAO BASIN

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Science China Chemistry 1982年第3期25卷 304-317页

作者：杨万里李永康高瑞祺郭庆福 Scientific Research and Derign Institute of daqing Petroleum Administrative bureau

Based on some composite indices, this paper proposes a classification of kerogen in theSongliao Basin and the four stages of hydrocarbon formation. A model of the evolution ofhydrocarbons in a large lake basin different from the model previously suggested ispresented. It is pointed out hi this paper that in a long subsiding, deep-water structural de-pression of a large eutrophic lake, the source rock formed under rapid, non-compensatoryconditions has the highest potential for petroleum. The thermal evolution of "combined"sapropelic kerogen (type Ⅰ) and the characteristics of petroleum formation are illustrated,The authors predict that the Songliao Basin is promising for further exploration.

关键词： In TYPE AND EVOLUTION MODEL OF CONTINENTAL KEROGEN IN THE SONGLIAO BASIN OC than

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STUDY ON THE PROVENANCE TEST OF DAHURIAN LARCH SELECTION OF BEST PROVENANCE

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Journal of Northeast forestry University 1993年第1期4卷 22-30页

作者： Yang Chuanping Xia De’an Xu Chuiqing Qi LizhiLiu Guifeng Weng Yuhui Sheng LiNortheast forestry UniversityWei Fuyou Zhang ZhengsuWangqin forestry bureau, Jilin Province Northeast forestry University China Wangqin forestry bureau Jilin Province

In this paper,it is studied that the growth characters of the progeny of 16provenance of larix gmelinii within the all 13 experimental sites by means of the analysis of va-riance,provenance stability,productivity index,rank correlation,synthetic index selection *** provenances were divided into three patterns:The first type have low and steady prod-uctivity;The second type have high but unsteady productivity;The third type is between theproductivity of the first and second *** the analysis on the feasibility and the reliabili-ty of the provenance early selection,the best provenances which lie in the southeast of theXiaoxingan *** regarded as the best and suitable for a large afforestation areas of *** in the north of Xingan Mt.,the local or the northwest provenances of theXiaoxingan *** be *** genetic gain was calculated on the basis of the provenanceheritability and the utilization of the best provenance were evaluated in this paper.

关键词： Larix gmelinii genetic gain Provenance selection Stability analysis Productivity index

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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

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DETERMINATION OF STATIC AND DYNAMIC DIFFUSION COEFFICIENTS OF MOISTURE IN PARTICLEBOARDS

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Journal of Northeast forestry University 1993年第2期4卷 87-92页

作者： Dai Fangtian Cai LipinNortheast forestry UniversityZhang ShufenWeihe forestry bureau, Heilongjiang Province Northeast forestry University China Weihe forestry bureau Heilongjiang Province

The static and dynamic diffusion coefficients are important coefficients to describe the moisture transfer processes in particleboard. In this paper, the formula of culculating the static and dynamic diffusion coefficients were deduced. At first, the static diffusion coefficients of four kinds of particleboards were determined by using diffusion cup method. The results demonstrated that the static diffusion coefficients parallel to panel surface were 10-20 times as large as that of perpendicular to panel surface for test boards. To determine both dynamic diffusion coefficients and surface emission coefficients of moisture in particleboards in one experimental period, specimens in four different thicknesses of each kind of particleboard were used in the experiment. Then the method of regression was used and the dynamic diffusion coefficients and surface emission coefficients were determined based on the slope and intercept of the regressive line.

关键词： Static diffusion coefficient Dynamic diffusion coefficient Moisture transfer

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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 Northeast forestry University China Dailing Experimental forestry bureau of Heilongjiang Province China 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

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Relationships between moment magnitude and fault parameters:theoretical and semi-empirical relationships

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 201-211页

作者：王海云陶夏新 Institute of Engineering Mechanics China Seismological BureauHarbin 150080China Daqing Petroleum InstituteDaqing 163318China Assistant Professor Institute of Engineering Mechanics China Seismological BureauHarbin 150080China Harbin Institute of TechnologyHarbin 150090China Professor

Fault parameters are important in earthquake hazard *** this paper,theoretical relationships between moment magnitude and fault parameters including subsurface rupture length,downdip rupture width,rupture area,and average slip over the fault surface are deduced based on seismological *** theoretical relationships are further simplified by applying similarity conditions and an unique form is ***,combining the simplified theoretical relationships between moment magnitude and fault parameters with seismic source data selected in this study,a practical semi-empirical relationship is *** seismic source data selected is also to used to derive empirical relationships between moment magnitude and fault parameters by the ordinary least square regression *** between semi-empirical relationships and empirical relationships show that the former depict distribution trends of data better than the *** is also observed that downdip rupture widths of strike slip faults are saturated when moment magnitude is more than 7.0,but downdip rupture widths of dip slip faults are not saturated in the molnent magnitude rangcs of this study.

关键词： earthquake hazard analysis fault paramcters seismic moment moment magnitude semi-empirical relationships.

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