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Modelling the response of larch growth to age,density,and elevation and the implications for multifunctional management in northwest China

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林业研究:英文版 2023年第5期34卷 1423-1436页

作者： Ao Tian Yanhui Wang Ashley A.Webb Pengtao Yu Xiao Wang Zebin Liu Institute of mountain Resource of guizhou Province Guiyang 550001People’s Republic of China Ecology and Nature Conservation Institute Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland AdministrationChinese Academy of ForestryBeijing 100091People’s Republic of China WaterNSW TamworthNSWAustralia

Plantations of Rupprecht's larch(Larix principis-rupprechtii)have been widely established in the drylands of northwest and north China under traditional fastgrowing plantation management *** strategies and the long-term logging ban have led to over-populated stands with lower structural and functional stability,less economic benefit and higher water *** guide the sustainable management of larch plantations,field surveys and historical data compilation were undertaken in the Liupan mountains of northwest *** main influencing factors(stand structure and site condition)and their effects on mean tree height,mean DBH and timber volumes were determined based on up-boundary line *** growth models coupling the effects of tree age,stand density,and elevation were *** height and DBH markedly increased initially and then slowly with tree age,decreased with stand density,and showed unimodal change with *** coupled growth models accounted for72-78%of the variations in tree height,DBH and timber *** for future plantation management are:(1)prolong the rotation to at least 60 years to produce large-diameter,high-quality timber and maintain greater carbon stocks;(2)zone the target functions of stands by elevation;and,(3)reduce stand density for balanced supply of multiple ecosystem *** growth models developed can predict growth response of larch plantations to density alteration under given ages and elevations,and assist the transformation from traditional management for maximum timber production to site-specific and multifunctional management with longer rotations and moderate tree density.

关键词： Larch plantations Coupled growth model Influencing factors Age Density Elevation

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Spatial-temporal distribution of debris flow impact pressure on rigid barrier

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Journal of mountain Science 2019年第4期16卷 793-805页

作者： LIU Dao-chuan YOU Yong LIU Jin-feng LI Yong ZHANG Guang-ze WANG Dong key laboratory of mountain Hazards and Earth Surface Processes and Institute of Mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences China Railway Eryuan Engineering Group co. LTD

Grain composition plays a vital role in impact pressure of debris flow. Current approaches treat debris flow as uniform fluid and almost ignore its granular effects. A series of flume experiments have been carried out to explore the granular influence on the impact process of debris flow by using a contact surface pressure gauge sensor(Tactilus~?, produced by Sensor Products LLC). It is found that the maximum impact pressure for debris flow of low density fluctuates drastically with a long duration time while the fluctuation for flow of high density is short in time, respectively presenting logarithmic and linear form in longitudinal attenuation. This can be ascribed to the turbulence effect in the former and grain collisions and grainfluid interaction in the latter. The horizontal distribution of the impact pressure can be considered as the equivalent distribution. For engineering purposes, the longitudinal distribution of the pressure can be generalized to a triangular distribution, from which a new impact method considering granular effects is proposed.

关键词： Debris flow Impact force Grain composition Spatio-temporal distribution Dynamic coefficient

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Reinvestigation of potential deformation during a heavy rainfall event in North China

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Atmospheric and Oceanic Science Letters 2020年第5期13卷 407-416页

作者： LI Na RAN Lingkun HU Jianhua GAO Shouting key laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Meteorological Disaster Prevention Technology Center of Jilin Province Jilin Meteorological ServiceJilinChina guizhou key Lab of Mountounious Climate&Resources Guizhou Institute of Mountain Environment and ClimateGuizhou Meteorological BureauGuiyangChina

In this study,the physical meaning and generation mechanism of potential deformation(PD)are reinvestigated.A main trait of PD is that it contains deformation,which is an important factor to precipitation but not well applied in precipitation *** paper shows PD shares similar features to deformation,but contains much more physical information than *** can be understood as a type of deformation of a thermodynamic-coupled vector(u*,v*).For convenient application,squared PD(SPD)is used instead for *** deriving the tendency equation of SPD,it is found that whether SPD is produced or reduced in the atmosphere is associated with the angle between the dilatation axes of PD and geostrophic *** the angle is less thanπ2,SPD is *** diagnostic results during a heavy rainfall event in North China on 20 July 2016 show that the process of rapid increase in precipitation can be well revealed by *** distribution of SPD becomes more organized and concentrated with increasing precipitation intensity.A diagnostic analysis of the SPD tendency equation shows that concentrated SPD is associated with the generation of SPD in the boundary layer followed by upward transport of the *** concentration of SPD indicates a confluence of precipitation-favorable factors—namely,vertical wind shear and moist baroclinity,which can enhance vertical motions and thus cause an increase in *** diagnostic results further verify PD as a useful physical parameter for heavy precipitation diagnosis.

关键词： Deformation potential deformation heavy precipitation

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Comparison in phytoplankton diversity-productivity-community stability between river-type reservoir and lake-type reservoir

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Journal of Oceanology and Limnology 2022年第4期40卷 1485-1507页

作者： Qiong WU Qiuhua LI Huan LUO Qian CHEN Huaxiang CHEN Yanjun DONG Shenghua LI College of environment Hohai UniversityNanjing 210098China Pearl River Water Resources Research Institute Guangzhou 510611China key laboratory of the Pearl River Estuary Regulation and Protection of Ministry of Water Resources Guangzhou 510611China Guangdong provincial Engineering Technology Research Center for Life and Health of River&Lake Guangzhou 510611China key laboratory for Information System of mountainous Area and Protection of Ecological environment of guizhou Province Guizhou Normal UniversityGuiyang 550001China Bureau of Ecological environment of Xunwu County of Jiangxi Province Xunwu 342200China

Relationship between biodiversity and ecosystem function is one of the core issues in ecological ***,as the main producer of aquatic ecosystem,its diversity,productivity,and community stability are of great signifi cance to reveal ecosystem *** are signifi cant diff erences in hydrodynamics,water retention time,and phytoplankton community structure between river-type reservoir and newly built lake-type *** comparative analysis of phytoplankton community stability between the two types of reservoir has not been *** Reservoir(river-type)and Taihu Reservoir(lake-type),the two reservoirs in the Dongjiang River source area of Zhujiang(Pearl)River Basin,were selected for comparison in terms of multi-year operation *** impoundment,river-type ***-type,and shallow water ***-deep water *** were collected in dry season(December 2019),normal season(March 2020),and wet season(August 2020),on which the phytoplankton diversity and productivity of the two reservoirs,and the relationship and diff erence of community stability were *** show that(1)the number of phytoplankton species in Jiuquwan Reservoir decreased comparing that before algal bloom and the restoration treatment,while that in Taihu Reservoir increased compared with that before the impoundment of the *** was no signifi cant diff erence in functional groups and species number between the two reservoirs(P>0.05);(2)the biological stability,diversity,productivity,and resource utilization effi ciency of newly built lake-type reservoir were higher than those of multi-year river-type *** addition,the utilization effi ciency of phytoplankton resources was the highest in wet season in both *** increases in biodiversity,richness,and evenness promoted the stability of the community,while increases in productivity and resource utilization effi ciency weakened the stability of the community;(3)community stabili

关键词： community stability functional group stability phytoplankton diversity resource utilization effi ciency reservoir

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Soil Heavy Metal Pollution and Health Risk Assessment of Abandoned Land in Coal Mining Areas in Xingren County

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Meteorological and environmental Research 2015年第11期6卷 19-25页

作者： Qin Fanxin Pang Wenpin Liu Wenzheng guizhou provincial key laboratory for Information System of mountainous Areas and Protection of Ecological environment Guizhou Normal University

Total contents of heavy metals （ Pb, Cr, Cd, Hg, As, Cu, Zn, and Ni） in 68 soil samples were determined to evaluate the contamination level of soil from five coal mine areas in Xingren County, guizhou province. The pollution levels of heavy metals were characterized by anthro- pogenic influence multiple, and the pollution of heavy metal in soil was evaluated using geo-accumulation index. Based on the health risk models recommended by the U.S. environmental Protection Agency （ US EPA）, the health risks of heavy metals in the soils were assessed. The results showed that the abandoned land in the five coal mining areas were contaminated by heavy metals, and the order of pollution levels of eight heavy metals was As 〉 Pb 〉 Cu 〉 Hg 〉 Ni 〉 Cr 〉 Cd 〉 Zn. The soils suffered moderate-heavy pollution from As and Pb, and the contents of As and Pb in the soils were 13.16 and 4.76 times higher than the background values of guizhou Province, followed by Cu, Hg and Ni , while soil pollution from Cr, Cd and Zn was mild. The order of non-caminogenic risks of the heavy metals in the soils was As 〉 Pb 〉 Cr 〉 Ni 〉 Cu 〉 Hg 〉 Cd 〉 Zn, and the non-carcinogenic dsk value of As was higher than that its threshold value 1, which indicated that As had a high potential health risk to adults and children. The order of carcinogen risks of the four heavy metals was As 〉 Cd 〉 Cr 〉 Ni, and the carcinogenic risk value of As was higher than its threshold value, indicating that As had a high carcinogenic risk to adults and children. The carcinogenic risk values of other three heavy metals （ Cd, Cr and Ni） were lower than the threshold value, so they had no carcinogenic risk to human health. Moreover, children were more sensitively affect- ed by heavy metals from the abandoned land. Therefore, the health of children in such areas should be paid more attention to. The HI value of the eight heavy metals to children was seven times higher than that to adults. The contribution rate of HQAs to HI was about 8

关键词： High-arsenic coal mining area Abandoned land Heavy metal Geo-accumulation index Health risk assessment China

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Comparative study of the stoichiometric characteristics of karst and non-karst forests in guizhou, China

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Journal of Forestry Research 2019年第3期30卷 799-806页

作者： Yabing Zhang Chuanyan Zhou Wenqiang Lv Lihua Dai Jingang Tang Shaoqi Zhou Lihua Huang Anding Li Jianli Zhang Institute of guizhou mountain Resources Guizhou Academy of SciencesGuiyang 550001GuizhouPeople’s Republic of China College of environment and Energy South China University of TechnologyGuangzhou 510640GuangdongPeople’s Republic of China guizhou Academy of Sciences Guiyang 550001Guizhou People’s Republic of China College of Resources and environmental Engineering Guizhou UniversityGuiyang 550025GuizhouPeople’s Republic of China

Carbon (C), nitrogen (N), and phosphorous (P) levels and their stoichiometry in plant components (leaves, branch trunks, roots) of trees in a karst forest and non-karst forest are compared. The results show that the C contents, C:N and C:P ratios of dominant species in the karst forest were lower than those in the non-karst forest, but the N and P and the N:P ratio were higher;C:N:P ratios in plant organs of trees in the karst forest were in the order of trunks>roots>branches>leaves. However, C:N:P ratio in the non-karst forest trees were trunks>branches>roots>leaves. Moreover, ratio of C:N:P in trunks was highest and lowest in leaves in both forests. In non-karst forest trees, N:P was in the order of leaves> roots>branches>trunks. There were no significant differences in the ratio of N:P in different plant components of trees in the karst forest. However, in karst and non-karst forest trees, the ratio of N:P in leaves was highest;positive correlations between N and P contents, and N and N:P ratios were observed in both karst and non-karst forests (p<0.001). Negative correlations between P and N:P ratios (p<0.05) were observed in karst forest trees, while positive correlations were observed in non-karst forest trees.

关键词： Karst forest Non-karst forest Stoichiometric characteristics Plant organs

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Evaluation on Potential Ecological Risk of Heavy Metals in Soil from Penglai Fairyland Park

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Asian Agricultural Research 2016年第6期8卷 75-79,86页

作者： Zhen YANG Di WU Zhun XIANG Chao KANG Fang WANG Zhu HUANG Lin ZHANG key laboratory of mountain Area and Protection of Ecological environment of guizhou Province Guizhou Normal University guizhou Institute of Biology

This study aims at evaluating the heavy metals pollution in soil collected from Penglai Fairyland Park in Guiyang,and predicting the harm of heavy metals to human health. Based on the background value of soil in guizhou and Soil environment Quality Standard( GB15618-1995),by using the geoaccumulation index method and Hakanson potential ecological risk assessment method,we research pollution characteristics and ecological risk of heavy metals in soil from the study area. The results show that from the index of geoaccumulation,the pollution level of heavy metals in agricultural soil from Penglai Fairyland Park is in the order of Ni > Cu > Hg > Cd > As > Zn > Cr > Pb. From the potential ecological harm index evaluation,soil is at slight ecological risk level in the park and the potential ecological hazard degree is in the order of Hg > Cd > Ni > As > Cu > Cr > Pb > Zn. The soil ecological environment in research area is only mildly damaged. Thus,the soil in research area is at the level of security,and it is suitable for cultivation of crops and less harmful to human health.

关键词： Soil Heavy metals Ecological damage Evaluation

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Organic matter pore characteristics of over-mature marine black shale: a comparison of organic fractions with different densities

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Frontiers of Earth Science 2023年第1期17卷 310-321页

作者： Shitan NING Peng XIA Niuniu ZOU Yi ZHONG Yin YU Yuliang MOU Ke WANG College of Resources and environmental Engineering Guizhou UniversityGuiyang 500025China key laboratory of Karst Georesources and environment Ministry of Education Guizhou UniversityGuiyang 500025China School of Geosciences China University of PetroleumQingdao 266580China

Organic matter pores are considered to be the most important type of pore for preserving hydrocarbon gases in shale gas *** organic matter in each over-mature marine shale sample was separated into two organic fractions with densities of greater than and less than 1.25 g/cm^(3),and then their molecular compositions and pore characteristics were quantitatively evaluated using solid state 13C-nuclear magnetic resonance(NMR)and gas(N2 and CO_(2))adsorption analyses,*** results revealed that aromatic carbon is the dominant molecular composition of the over-mature organic matter in the Lower Cambrian Niutitang *** the over-mature stage,the organic fractions with densities of greater than and less than 1.25 g/cm^(3) have no significant differences in molecular *** organic fractions with densities of greater than and less than 1.25 g/cm^(3) do have significant differences in their organic pore *** contrast to the high density organic fraction,the low density fraction contained abundant micropores and lacked mesopores and *** organic pore structures of the different occurrence states of organic matter were significantly *** C/O of organic matter in different occurrence states are obviously different,which proves that the organic pore structure is closely related to both the occurrence state and density of the organic ***,these relationships are still unclear and require further study.

关键词： pore characteristics organic matter black shale Early Cambrian Yangtze Block

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Autotoxicity of Phthalate Esters in Tobacco Root Exudates:Effects on Seed Germination and Seedling Growth

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Pedosphere 2017年第6期27卷 1073-1082页

作者： DENG Jiajun ZHANG Yanling HU Jiwei JIAO Jiaguo HU Feng LI Huixin ZHANG Shixiang Soil Ecology laboratory College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095(China) ~hengzhou Tobacco Research Institute of CNTC Zhengzhou 450001(China) guizhou provincial key laboratory for Information System of mountainous Areas and Protection of Ecological environment Guizhou Nounal UniversityGuiyang 550001(China) Testing Center of Agro-Product Quality and Safety of Jiangxi Province Nanchang 330046(China) key laboratory of Eco-environmental and Tobacco Leaf Quality of CNTC Zhengzhou 450001(China)

Autotoxicity is one of the major factors that impede continuous *** is defined as the toxic influence of chemicals released from one plant species on the germination and growth of individuals of the same ***, in order to exam the autotoxicity of tobacco root exudates, root exudates were collected from tobacco plants grown both in cultural solution and on natural *** ultraperformance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry, main autotoxic chemical substances in the root exudates were *** autotoxic effects of suspected autotoxins on seed germination(including germination rate,germination potential, germination index, and vigor index) and seedling growth were *** phthalate(or diisobutyl phthalate), dioctyl phthalate, and diisooctyl phthalate were identified in tobacco root *** was observed that high concentrations(greater than 0.5 mmol L^(-1)) of each identified phthalate ester caused significant(P < 0.05) inhibition of tobacco seed germination and seedling *** can be concluded that phthalate esters such as dibutyl phthalate, diisobutyl phthalate, and diisooctyl phthalate in tobacco root exudates may play an important role in tobacco autotoxicity.

关键词： autotoxins germination index germination potential germination rate vigor index

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Analysis of genetic diversity and prediction of Larix species distribution in the Qinghai–Tibet Plateau,China

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Journal of Forestry Research 2023年第3期34卷 705-715页

作者： Qiqiang Guo Huie Li Weilie Zheng Jinwen Pan Jie Lu Jiangrong Li Yu Zheng Institute for Forest Resources&environment of guizhou Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou ProvinceGuizhou UniversityGuiyang 550025People’s Republic of China College of Forestry Guizhou UniversityGuiyang 550025People’s Republic of China College of Agriculture Guizhou UniversityGuiyang 550025People’s Republic of China Institute of Tibet Plateau Ecology Tibet Agriculture and Animal Husbandry UniversityNyingchi Tibet 860000People’s Republic of China key laboratory of Forest Ecology in Tibet Plateau(Tibet Agriculture and Animal Husbandry University) Ministry of EducationNyingchi Tibet 860000People’s Republic of China Plant Research Center Chengdu Botanical GardenChengdu 610083People’s Republic of China

Larix resources in the Qinghai-Tibet Plateau have important ecological and economic ***,the lack of genetic diversity background and related research hinders the development of conservation *** this study,genetic diversity and distribution of fi ve Larix species were *** 19 polymorphic microsatellite markers to study 272 representative individuals from 13 populations,the results show low genetic diversity at the population level,with variation explained mainly by diff erentiation among *** Larix populations were classifi ed into two clades,one formed by eight populations,including three of the species in this study,***,***,and *** *** other clade consists of fi ve populations,including the other two species in this study,*** thii and *** distance of the species was aff ected by geographical isolation and genetic diversity was mainly aff ected by *** area suitable for Larix *** during the Last Glacial Maximum compared to the current distribution according to the niche model,but should increase in future climate scenarios(2050s),expanding westward along the *** results provide an important scientifi c basis for the development of conservation strategies and further the sustainable utilization of Larix resources in the Qinghai-Tibet Plateau.

关键词： Larix spp. Genetic diversity Phylogenetic relationship Genetic structure Ecological niche modeling Qinghai-Tibet Plateau

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