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THE PATTERN OF FIRE DISTURBANCE IN LIANGSHUI NATURE RESERVE

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Journal of Northeast forestry University 1996年第4期7卷 12-14页

作者：陈动郭郢吴兴利那守海 Northeast forestry University Harbin China Langxiang forestry bureau China Northeast forestry University China

Fire disturbance pattem of Liangshui Nature Reserve was studied by investigating fire scar tree and analyzing distribution of charcoal particle in soil-layer. The results show that : fire disturbance regular is related with the accumulation and disposition of fuels in space pattern. rye fire protection measures wers put forward for Liangshui Nature Reserve.

关键词： Fire disturbance,pattem Fuels accumulation

Molecular characterization and functional analysis of daf-8 in the pinewood nematode,Bursaphelenchus xylophilus

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Journal of forestry Research 2022年第2期33卷 689-698页

作者： Jinghan Wang Huan Hong Rong Xie Jingjing Ji Kai Guo Liqun Bai Jia Tang Hongshi Yu Jianren Ye Jiafu Hu Nanjing forestry University Nanjing 210037China Zhejiang Agricultural and forestry University Hangzhou 311300China Yuhuan Natural Resources and Planning bureau Taizhou 317600China School of BioSciences The University of MelbourneParkvilleVIC 3010Australia

Bursaphelenchus xylophilus,causal agent of pine wilt disease,causes extensive damage ***-gies are needed to inhibit population growth or block the spread of the invasive nematode to control pine wilt *** gene daf-8 plays crucial roles in larval develop-ment and dauer formation in Caenorhabditis elegans,but little is known about its orthologue in *** the present molecular characterization and functional analysis of daf-8 in ***(Bx-daf-8),RT-qPCR showed that the expression of Bx-daf-8 gradually increased during the embryonic stage,peaked in the second-stage juvenile(J2),then dramatically dropped in the J3,and remained at that low level for the rest of its ***-daf-8-transgenic *** was employed to mimic the spatiotemporal expression of Bx-daf-8,which was expressed close to the pharynx during early embryogenesis and weakly throughout the whole body during late *** was observed in head neurons and tail ganglions throughout all postembryonic *** embryos were severely abnormal,and hatching rate decreased sharply after Bx-daf-8 ***-16-1 and da-f16-2,downstream genes in the IIS pathway,also dropped sharply after Bx-daf-8 *** propose that TGFβmay crosstalk with the IIS pathway upstream of Bx-daf-16 and that daf-8 may act as a master regulator of daf-16 in ***,knockdown of Bx-daf-8 did not lead to constitutive developmental arrest at the dauer larval stage,indicating that dauer entry in *** might be controlled by several genes and is more complicated than in ***-daf-8 alone did not control the dauer entry in ***,but it was indispensable for embryogen-esis,providing a potential target for suppressing population growth of ***.

关键词： Daf-8 Expression pattern RNAi Embryogenesis Bursaphelenchus xylophilus

Exploring the spatiotemporal heterogeneity of vegetation changes in subtropical humid karst region under CO2 fertilization

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Journal of Geographical Sciences 2025年第1期 65-87页

作者： CHEN Meng ZHOU Qiuwen PENG Dawei YAN Weihong School of Geography and Environmental Science Guizhou Normal University Huanjiang Observation and Research Station for Karst Ecosystem Guangxi Key Laboratory of Karst Ecological Processes and Services Institute of Subtropical Agriculture CAS University of Chinese Academy of Sciences Faculty of Geographical Science Beijing Normal University forestry bureau of Shibing County

Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide （CO2） fertilization in hot and humid *** subtropical humid karst region is a hot and humid region;whether and to what extent CO2fertilization affects vegetation changes in such regions remains *** this study,we investigated the degree to which CO2fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression *** showed that CO2fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO2fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau *** studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these *** findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions.

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Comparison of locomotor behaviour between white-headed langurs Trachypithecus leucocephalus and Franois' langurs T. franoisi in Fusui,China

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Current Zoology 2009年第1期55卷 9-19页

作者： Jinrong XIONG Shihua GONG Chenggang QIU Zhaoyuan LI Faculty of Conservation Biology Southwest Forestry University Kunming 650224 China Department of Wildlife Conservation Guangxi Forestry Bureau Nanning 530022 China Biodiversity and Nature Conservation Centre Southwest Forestry University Kunming 650224 China

We studied the locomotor behaviour of white-headed langurs Trachypithecus leucocephalus and Francois＇ langurs *** to test two hypotheses：（1） these monkeys have evolved locomotor ability to support their activities on limestone hills, and （2） Francois＇ langurs have evolved more diverse locomotor skills than white-headed langurs. Data were collected from 1996 - 1998 and in 2005 in Fusui Nature Reserve, Guangxi, and showed that the two species had similar locomotor types, but Francois＇ langurs had more locomotor modes （26） than white-headed langurs （12）. Quadrupedal walking and leaping were two major types, and white-headed langurs were more arboreal than Francois＇ langurs. We suggest that, while keeping their ancestral locomotor types, the two species have evolved new types allowing them to live on limestone cliffs. Compared to white-headed langurs, Francois＇ langurs have more diverse locomotor modes that probably have allowed them to live in more habitat types. As an evolutionary outcome, Francois＇ langurs have a larger distribution range .

关键词： Locomotor behaviour Evolution White-headed langurs Francois' langurs

Approximately-Balanced Drilling in daqing Oilfield

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Journal of China University of Geosciences 2004年第1期15卷 128-132页

作者： XiaBairu ZhengXiuhua LiGuoqing TianTuo School of Engineering＆Technology China University of GeosciencesBeijing100083China daqing Petroleum Administration bureau Daqing163001China

The daqing oilfield is a multilayered heterogeneous oil field where the pressure are different in the same vertical profile causing many troubles to the adjustment well drillings. The approximately-balanced drilling technique has been developed and proved to be efficient and successful in daqing oilfield. This paper discusses the application of approximately-balanced drilling technique under the condition of multilayered pressure in daqing oilfield, including the prediction of formation pressure, the pressure discharge technique for the drilling well and the control of the density of drilling fluid.

关键词： approximately-balanced drilling pore pressure reasonable negative pressure value density of drilling fluid pressure discharge for drilling well.

Variations in Uptake and Translocation of Copper, Chromium and Nickel Among Nineteen Wetland Plant Species

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Pedosphere 2010年第1期20卷 96-103页

作者： LIU Jian-Guo LI Guang-Hui SHAO Wan-Chen XU Jia-Kuan WANG De-Ke School of Environmental & Safety Engineering Jiangsu Polytechnic University Changzhou 213164 (China) Changzhou Agricultural and forestry bureau Changzhou 213001 (China)

An experiment was carried out to investigate the variations in metal uptake and translocation among 19 wetland plant species in small-scale plots of constructed wetland using artificial wastewater containing 2.0 mg L^-1 copper （Cu）, 1.0 mg L^-1 chromium （Cr）, and 2.0 mg L^-1 nickel （Ni）. More than 97% of Cu, Cr, and Ni were removed from the wastewater by the wetland plant species. There were more than ]00-fold differences in the metal accumulation and more than ten-fold differences in the metal concentrations among the 19 plant species. These plants accumulated as high as 8.8% of Cu, 20.5% of Cr, and 14.4% of Ni when they were grown in the wetland soaked with the wastewater. Several plant species were found to be highly capable of accumulating one, two or all the three metals. The results indicated considerable variations in the metal removal abilities through phytoextraction among the 19 wetland plant species. It can be concluded that the selection of appropriate plant species in constructed wetland can be crucial for the improvement of metal removal efficiency of the wetland system.

关键词： constructed wetland heavy metal phytoextraction wastewater treatment

Optimum nitrogen fertilization of Calophyllum inophyllum seedlings under greenhouse conditions

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Frontiers of Agricultural Science and Engineering 2016年第4期3卷 368-374页

作者： Wentao ZOU Ruifeng JIA Jinchang YANG Rongsheng LI Guangtian YIN Research Institute of Tropical forestry Chinese Academy of Forestry Rural Work bureau of High Tech Industry Development Zone in Huizhou

A greenhouse pot experiment was conducted to study the effects of nitrogen fertilization on Calophyllum inophyllum seedlings grown with 0, 50, 100, 150,200, 300, 400 and 600 mg N per seedling according to exponential functions. Seedling height, root collar diameter, leaf area and total biomass increased with increasing fertilization from 0 to 200 mg N per seedling and decreased with further increase in fertilization from300 to 600 mg N per seedling. The net photosynthetic rate,stomatal conductance, intercellular CO_2 concentration and transpiration rate of C. inophyllum seedlings showed a unimodal parabolic trend, with peak values of7.29 mmol·m^(–2)·s^(–1), 0.071 mol·m^(–2)·s^(–1), 220 mmol·mol^(–1) and 1.34 mmol·m^(–2)·s^(–1), respectively, when the rate of fertilization was 200 mg N per seedling. Photosynthetic gas exchange parameters were significantly different among nitrogen treatments. Based on the critical values of leaf N and P concentration and N/P ratio, the optimum amount of nitrogen of C. inophyllum seedlings was 200–400 mg per seedling for leaf N and P concentration, and100–400 mg per seedling for N/P ratio. It was concluded that 200–400 mg N per seedling was the most suitable nitrogen range for C. inophyllum seedlings.

关键词： Calophyllum inophyllum growth nitrogen fertilization nutrient status photosynthesis

La(Ⅲ)-loaded bentonite/chitosan beads for defluoridation from aqueous solution

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Journal of Rare Earths 2014年第5期32卷 458-466页

作者：张艺徐莹崔昊刘炳杰高翔汪东风梁鹏 College of Food Science and Engineering Ocean University of China Ocean and Fishery bureau of Lianyungang City College of Food Science and Technology Fujian Agriculture and Forestry University

Developing low-cost and effective materials for excess fluoride removal is important for providing safe water. A novel ad- sorbent, La（IlI）-loaded bentonite/chitosan beads （La-BCB） was prepared for defluoridation from aqueous solution. The effects of various parameters such as dosage of La（III）, pH, temperature, contact time, initial fluoride concentration and presence of co-existing anions were investigated to examine the defluoridation behavior. The maximum defluoridation capacity of La-BCB was 2.87 mg/g at pH 5, 30 ℃. Scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDX） and Fourier transform infrared spectros- copy （FTIR） were employed to analyze the characteristics of La-BCB. The equilibrium fluoride adsorption data fitted well with both Langmuir and Freundlich isotherm models. The RL value revealed that the defluoridation process using La-BCB was favorable. The adsorption kinetics followed pseudo-second order kinetic as well as particle and intraparticle diffusion models. The presence of car- bonate and bicarbonate reduced defluoridation capacity of La-BCB while sulphate, nitrate and chloride showed slight effect. The ex- hausted La-BCB was regenerated using sodium hydroxide with only 17% loss. The reasonable defluoridation mechanism could be interpreted as adsorption and ion exchange.

关键词： La(III) bentonite chitosan beads defluoridation adsorption fluoride rare earths

Clones No 1333 of Populus alba×*** and No 1132 of ***×***×***

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Journal of forestry Research 1997年第2期8卷 74-76页

作者：王继军刘玉纯张方春陆国君彭勇军 Yingchun forestry bureau Yichun Heilongjiang P. R. China Yingchun forestry bureau Heilongjiang P. R. China

The hybridization experiment was initiated in 1975, in which the parents of P davhaana were collectedfrom Dailing, Heilongiiang Province, P. suaveolens were from Baicheng, P. simonii from Zhaodong of Heilongjiang Prov-ince, and P. tremula from Shanxi Province. Clones No 1333 of P. Alba x P. davidiana and No 1132 of P davidiana x (Palba x P. davidiana F1) had greater genetic variation and heritability in clones tested.

关键词： Clones,Hybridization Aspen