检索结果-南通市图书馆

The anatomical structure of woody plants in arid habitats is closely related to nonstructural carbohydrates storage

Forest Ecosystems 2022年第6期9卷 764-774页

作者： Zedong Li Xinxiao Yu Guodong Jia key laboratory of state forestry and Grassland administration on soil and water conservation Beijing Forestry UniversityBeijing100083China

Background:The high temperatures and drought conditions associated with global climate change have led to the widespread death of trees and forests,which has generated research interest in the impact of non-structural carbohydrates(NSC)reserves on woody plant survival in changing environments.The anatomical characteristics of plants can affect the scale and variability of NSC reserves,and linking the anatomical characteristics of trees to NSC concentration can help answer questions about the potential role of NSC in the repair of xylem embolism during drought.Results:The anatomical characteristics,NSC concentrations and gas exchange parameters were determined in 16 common afforestation tree species in typical arid limestone habitats in rocky mountain regions.We found that the anatomical structures varied greatly among the tree species studied,and a branch xylem hydraulic efficiency-safety tradeoff was not observed.NSC concentration was significantly and positively correlated with variables including mean vessel diameter(MVD),maximum vessel diameter(XVD),potential hydraulic conductivity(Kp),vessel wall thickness(VWT),ratio of palisade tissue thickness to sponge tissue thickness(PT/ST),net photosynthetic rate(Pn),water use efficiency(WUE)and axial parenchyma cell area,and negatively with sponge tissue thickness(ST)and lower epidermis thickness(LET)of leaves.Among the four latent variables,mechanical strength was inversely related to NSC concentration,whilst hydraulic efficiency,leaf carbon fixation,and the embolism repair and storage capacity all had a positive effect.Conclusions:Our study revealed that tree species with larger vessel diameters,thicker vessel walls,more abundant axial parenchyma,and higher PT/ST have higher NSC storage in arid habitats in northern China.Varying xylem anatomical characteristics and leaf anatomical characteristics among different tree species lead to differentiated water transport and photosynthetic processes,thereby regulating the NSC concentrations.A higher NSC concentration may en

关键词： Drought Embolism Leaf anatomy NSC concentration Xylem

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Trees as large-scale natural phononic crystals: Simulation and experimental verification

引用

International soil and water conservation Research 2019年第2期7卷 196-202页

作者： Jiankun Huang Yifan Liu Yaguang Li Key Laboratory of State Forestry Administration on Soil and Water Conservation School of Soil and Water ConservationBeijing Forestry UniversityBeijingChina

Urban trees are usually planted on a periodic layout in the spatial configuration.We regard urban trees as large-scale natural phononic crystals.The entire forest is reduced to a reasonable 'tree-soil' unit cell based on the phononic crystal theory and finite element method by COMSOL software is used to obtain the dispersion curves.The Rayleigh wave band gaps of phononic trees are distinguished by the sound cone method.The influences of soil elastic modulus and tree height on band gaps are investigated.A three-dimensional simulation model and experiment test are applied to validate the effect of phononic trees on vibration control.The numerical frequency reduction zones coincide exactly with the theoretical band gaps.Increasing soil stiffness results in a higher-frequency and wider band gap.An increasing tree height is beneficial to obtain low-frequency band gaps.A periodically arranged plantation that Rayleigh wave band gaps at frequency ≤60 Hz could be designed.This study opens up a new theoretical basis for the quantitative analyses of urban trees to the ground vibration mitigation at a certain frequency range.

关键词： Urban trees Phononic crystal Dispersion curve Band gap Rayleigh wave

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Size-and leaf age-dependent effects on the photosynthetic and physiological responses of Artemisia ordosica to drought stress

引用

Journal of Arid Land 2021年第7期13卷 744-758页

作者： WANG Chunyuan YU Minghan DING Guodong GAO Guanglei ZHANG Linlin HE Yingying LIU Wei Yanchi Research Station School of Soil and Water ConservationBeijing Forestry UniversityBeijing 100083China Key Laboratory of State Forestry Administration on Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China

Drought is one of the most significant natural disasters in the arid and semi-arid areas of China.Populations or plant organs often differ in their responses to drought and other adversities at different growth stages.At present,little is known about the size-and leaf age-dependent differences in the mechanisms of shrub-related drought resistance in the deserts of China.Here,we evaluated the photosynthetic and physiological responses of Artemisia ordosica Krasch.to drought stress using a field experiment in Mu Us Sandy Land,Ningxia Hui Autonomous Region,China in 2018.Rainfall was manipulated by installing outdoor shelters,with four rainfall treatments applied to 12 plots(5 m×5 m).There were four rainfall levels,including a control and rainfall reductions of 30%,50%and 70%,each with three replications.Taking individual crown size as the dividing basis,we measured the responses of A.ordosica photosynthetic and physiological responses to drought at different growth stages,i.e.,large-sized(>0.5 m^(2))and small-sized(≤0.5 m^(2))plants.The leaves of A.ordosica were divided into old leaves and young leaves for separate measurement.Results showed that:(1)under drought stress,the transfer efficiency of light energy captured by antenna pigments to the photosystem II(PSII)reaction center decreased,and the heat dissipation capacity increased simultaneously.To resist the photosynthetic system damage caused by drought,A.ordosica enhanced its free radical scavenging capacity by activating its antioxidant enzyme system;and(2)growth stage and leaf age had effects on the reaction of the photosynthetic system to drought.Small A.ordosica plants could not withstand severe drought stress(70%rainfall reduction),whereas large A.ordosica individuals could absorb deep soil water to ensure their survival in severe drought stressed condition.Under 30%and 50%rainfall reduction conditions,young leaves had a greater ability to resist drought than old leaves,whereas the latter were more resistant to severe drought stress.The response of A.ordos

关键词： drought stress age difference plant size photosynthesis physiological response survival strategy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Overland flow resistance and its components for slope surfaces covered with gravel and grass

引用

International soil and water conservation Research 2022年第2期10卷 273-283页

作者： Lan Ma Chengzhong Pan Jingjing Liu key laboratory of state administration of forestry and Grassland on soil and water conservation School of Soil and Water ConservationBeijing Forestry UniversityBeijing100083China Beijing key laboratory of Urban Hydrological Cycle and Sponge City Technology College of Water SciencesBeijing Normal UniversityBeijing100875China soil and water conservation Monitoring Center of Haihe Basin of Haihe water Resources Commission of the Ministry of water Resources Tianjin300170China

Overland flow resistance plays an important role in predicting hillslope hydrological and erosion pro-cesses on hillslopes.soil surfaces covered with grass and/or gravel may increase hydraulic resistance to overland flow,but there is little information on the determination on these resistance components in a composite slopeland.In this study,the smooth and sand-bed surfaces covered with different gravel or/and grass(cover degree¼2.5%,5%,10%,15%,20%)under five slope gradients(3,6,9,12,15)were subjected to inflows to investigate the hydraulic resistance and validate the sum law of resistance components.The results showed that,the overland flow mainly belonged to transition or turbulent and supercritical flow regime with 150soil and water conservation measures in the rocky and mountainous areas.

关键词： Overland flow Resistance Grass Gravel Sum law

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Environmental and canopy conditions regulate the forest floor evapotranspiration of larch plantations

引用

Forest Ecosystems 2022年第5期9卷 606-616页

作者： Zebin Liu Yanhui Wang Pengtao Yu Lihong Xu Songping Yu key laboratory of Forest Ecology and Environment of National forestry and Grassland administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing100091China School of soil and water conservation Beijing Forestry UniversityBeijing100083China

Background:Integrated forest-water management focusing on forest-water coordination is an important way to alleviate water use conflicts among forests and other sectors in vast dryland regions.Forest floor evapotranspiration(FE),which is an important component of forest evapotranspiration,accounts for a large proportion of the water consumed in arid forests.Elucidating how environmental and canopy conditions impact FE has important significance for guiding integrated forest-water management in a changing environment.Methods:The microlysimeter(ML)-measured evapotranspiration(FE_(ML)),reference evapotranspiration(ET_(o)),volumetric soil moisture(VSM),and canopy leaf area index(LAI)were monitored in a Larix principis-rupprechtii plantation located in the semi-humid Liupan Mountains of Northwest China in 2019(June–September)and 2021(May–September).The response functions of the FE coefficient(the ratio of daily FEML to ET_(o))to the individual factors of VSM and LAI were determined using upper boundary lines of scatter diagrams of measured data.The framework of the daily FE(FE_(ML))model was established by multiplying the response functions to individual factors and then calibrated and validated using measured data to assess the FE response to environmental and canopy conditions.Results:(1)The FE coefficient increased first rapidly and then slowly with rising VSM but decreased slowly with rising LAI.(2)The simple daily FE(FE_(ML))model developed by coupling the impacts of ET_(o),LAI,and VSM in this study performed well for predicting FE.(3)The impacts of ET_(o),LAI,and VSM were quantified using the FE(FE_(ML))model,e.g.,at a given VSM,the impact of ETo on FE increased obviously with decreasing LAI;at a given ET_(o),the impact of LAI on FE increased with rising VSM.(4)In the two study years,when directly using the microlysimeter measurement,the real FE on the forest floor was overestimated when the VSM in microlysimeters was above 0.215 but underestimated below 0.215 due to the difference in VSM from the forest floor.T

关键词： Larch plantation Forest floor evapotranspiration Reference evapotranspiration soil water content Canopy structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Quantitative comparison of semi- and fully-distributed hydrologic models in simulating flood hydrographs on a mountain watershed in southwest China

引用

Journal of Hydrodynamics 2013年第6期25卷 877-885页

作者：张会兰王玉杰王云琦李丹勋王兴奎 key laboratory of soil and water conservation and Desertification Combating Ministry of EducationDepartment of Soil and Water ConservationBeijing Forestry University state key laboratory of Hydroscience and Engineering Tsinghua University key laboratory of soil and water conservation and Desertification Combating Ministry of EducationSchool of Soil and Water ConservationBeijing Forestry University

To investigate the performance of fully- and semi-distributed hydrologic models in simulating the process of transformation from rainfall to runoff in mountain areas, the fully-distributed models Basin Pollution Calculation Center （BPCC） and HEC- HMS are calibrated for the Zhenjiangguan watershed located in the upper stream of Minjiang River Southwest China using streamflow observations at the basin outlet. Semi-automatical optimization method is implemented to both models to improve simulated resuits by removing artificial errors. Based on the consistency of the simulated hydrographs with the observed ones, the statistical coefficients such as the relative error, the probability distribution and the correlation coefficient, are further introduced to evaluate quantitatively the performance of the two models. Analyses indicate that the hydrographs simulated by the BPCC are relatively closer to the observed ones than those simulated by the HEC-HMS in view of the spatial heterogeneity in terrain, soil texture, land cover and meteorological conditions in mountain areas.

关键词： Basin Pollution Calculation Center （BPCC） HEC-HMS hydrologic modeling mountain area semi-automaticallyoptimization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of forest cover type and ratio changes on runoff and its components

引用

International soil and water conservation Research 2022年第3期10卷 445-456页

作者： Bingbing Ding Yonge Zhang Xinxiao Yu Guodong Jia Yousheng Wang Yusong Wang Pengfei Zheng Zedong Li The Metropolitan Area Forest Ecosystem Research Station School of Soil and Water ConservationBeijing Forestry UniversityBeijing100083PR China key laboratory of state forestry and Grassland administration on soil and water conservation Beijing Forestry UniversityBeijing100083PR China Institute of Sediment Research China Institute of Water Resources and Hydropower ResearchBeijing100038PR China

Changes in forest cover can affect not only the total runoff from a watershed,but also the runoff components(e.g.,surface runoff,interflow,groundwater flow).In this study,based on the WetSpa model simulation method and the recursive digital filtering(RDF)method,the Banchengzi watershed in the mountainous region of Beijing,China,was selected to investigate how changes in forest cover type and cover percentage affect total runoff,surface runoff,interflow,and groundwater flow through scenario settings.Our results show that the difference between the WetSpa model and the RDF method for separating runoff components is small,with only 4.7%and 0.4%difference between the calibration and validation periods.Total runoff in different forest types followed the order shrub forest>coniferous forest>mixed forest>broadleaf forest.Regarding runoff components,the proportions of baseflow(sum of interflow and groundwater flow)to total runoff were 61.1%and 60.8%for broadleaf and mixed forests,which was significantly higher than those of 53.0%and 43.1%for coniferous and shrub forests.However,the proportion of shrub forest baseflow was high in wet years,and that of broadleaf forest baseflow was high in normal and dry years.The proportions of interflow and groundwater flow from various forest cover types to total runoff continued to increase with increasing forest cover rate.Our results have important implications for the implementation of afforestation projects and forest conservation programs,contributing to water resource regulation and ecosystem protection in watersheds.

关键词： Forest cover types Forest cover ratios WetSpa Runoff separation Runoff components

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Impacts of environmental and canopy conditions on the nighttime sap flow of larch plantations in the Liupan Mountains,China

引用

林业研究:英文版 2023年第6期34卷 1927-1940页

作者： Songping Yu Jianbin Guo Zebin Liu Yanhui Wang Lihong Xu Pengtao Yu Liang He School of soil and water conservation Beijing Forestry UniversityBeijing 100083People’s Republic of China key laboratory of Forest Ecology and Environment of National forestry and Grassland administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091People’s Republic of China

Nighttime sap flow(Q_(n))is an important physiological activity under which trees manage drought stress.An in-depth understanding of the characteristics of Q_(n)and its response to environmental and canopy conditions are of significance for arid area forest and water management.This study measured daily sap flow(Q_(s))of a Larix principis-rupprechtii plantation in the Liupan Mountains,northwest China during the 2017-2019 growing seasons,and separated Q_(s)into daytime sap flow(Qd)and Q_(n).Meteorological conditions(reference evapotranspiration,ETref),canopy structure(leaf area index,LAI),and soil moisture(relative soil water content,RSWC)were considered as the main biophysical factors affecting Q_(n).The structural equation model and upper boundary line method determined the effects of compound and single factors on Q_(n)The daily mean Q_(n)values during the growing seasons in 2017,2018,and 2019 were 0.024,0.026,and 0.030 mm d-1,accounting for 6.2,11.2,and 10.1%of Q_(s),respectively.Q_(n)at different canopy development phases(leaf expanding,LG;leaf expanded,LD;and defoliation,DF)over three years was LD>LG>DF.Q_(n)increased with increasing ETref,whereas the ratio of Q_(n)to Q_(s)decreased.Q_(n)did not show regular variation in the three-year growing seasons under different soil moisture conditions.ETrefand LAI mainly controlled Q_(n)by affecting Qd,whereas RSWC had no significant effect on Q_(n).Q_(n)had a positive and linear relationship with LAI and a quadratic relationship with ETref.Both explained 40%of variation in Q_(n)Meteorological and canopy conditions are important factors affecting Q_(n)on the semi-humid study site.The application of the Q_(n)model coupled with the impact of ETrefand LAI furthers understanding of the impacts of climate and forest structure change on Q_(n).

关键词： Nighttime sap flow Reference evapotranspiration Leaf area index soil moisture Multifactor impact

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Spatiotemporal patterns of the forage-livestock balance in the Xilin Gol steppe,China:implications for sustainably utilizing grassland-ecosystem services

引用

Journal of Arid Land 2021年第2期13卷 135-151页

作者： QU Yingbo ZHAO Yuanyuan DING Guodong CHI Wenfeng GAO Guanglei Key Laboratory of State Forestry Administration on Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Yanchi Research Station School of Soil and Water ConservationBeijing Forestry UniversityBeijing 100083China College of Resources and Environmental Economics Inner Mongolia University of Finance and EconomicsHohhot 010017China

Understanding the spatiotemporal patterns of the forage-livestock balance is imperative for regionally arranging animal husbandry production while ensuring sustainable grassland-ecosystem service use.The Xilin Gol steppe is an important native grassland resource in Inner Mongolia Autonomous Region,China.This study aimed to elucidate the dynamics of the forage-livestock balance in the Xilin Gol steppe during the period 2000–2015.We evaluated the forage production and corresponding livestock carrying capacity(LCC)in the growing seasons of 2000–2015 using remote sensing data and field surveys.The spatiotemporal patterns of the forage-livestock balance were then assessed at regional,city(including city,county and banner),and village scales using statistical and household survey data.The results showed that both forage production and LCC decreased in the Xilin Gol steppe from east to west.During the period 2000–2015,the regional average forage production and corresponding LCC fluctuated without following a distinct trend,but were consistent with the variations in precipitation.The forage-livestock balance varied with time,space,and scale.At the regional scale,steppes were overgrazed in the early 2000s,but a forage-livestock balance or even grazing potential was achieved in other years.At the city scale,approximately half of the region exhibited a"forage-livestock balance"since 2000.However,about half of the region still experienced overgrazing,which mainly located in the southwest sandy zones.Such changes may have been affected by the variations in grassland quality,forage production,compensation payment,and so on.We suggest a location-specific management scheme for grazing constraints,ecological compensation payment,and industry development to aid in harmonizing animal husbandry and environmental restoration,while promoting sustainable development goals by 2030.

关键词： forage production livestock carrying capacity forage-livestock balance Xilin Gol steppe sustainable development

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influence of physiological and environmental factors on the diurnal variation in emissions of biogenic volatile compounds from Pinus tabuliformis

引用

Journal of Environmental Sciences 2019年第7期31卷 102-118页

作者： Jungang Chen Huaxing Bi Xinxiao Yu Yanlin Fu Wenchao Liao College of soil and water conservation Beijing Forestry University Institute of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Ji County Station Chinese National Ecosystem Research Network (CNERN) Key Laboratory of State Forestry Administration on Soil and Water Conservation Beijing Forestry University Beijing Engineering Research Center of soil and water conservation Beijing Forestry University Engineering Research Center of forestry Ecological Engineering Ministry of Education Beijing Forestry University Beijing Collaborative Innovation Center for Eco-Environmental Improvement With forestry and Fruit Trees Beijing water Consulting Co. LTD

Biological volatile organic compounds(BVOCs) have a large influence on atmospheric environmental quality, climate change and the carbon cycle. This study assesses the composition and diurnal variation in emission rates of BVOCs from Pinus tabuliformis, using an enclosure technique. Environmental parameters(temperature and light intensity) and physiological parameters(net photosynthetic rate, P_n; stomatal conductance, g_s; intercellular CO_2 concentration, C_i; and transpiration rate, T_r) that may affect emission behavior were continuously monitored. The 10 most abundant compound groups emitted by P. tabuliformis were classified by gas chromatography–mass spectrometry. The dominant monoterpenoid compounds emitted were α-pinene, β-myrcene, α-farnesene and limonene. The diurnal emission rate of BVOCs changed with temperature and light intensity, with dynamic analysis of BVOCs emissions revealing that their emission rates were more affected by temperature than light. The variation in monoterpene emission rates was consistent with estimates of P_n, g_s and T_r. Basal emission rates(at 30 °C,) of the main BVOCs ranged from 0.006 to 0.273 μg^(-1)/(hr g),while the basal ER standardization coefficients ranged from 0.049 to 0.144 °C^(-1). Overall, these results provide a detailed reference for the effective selection and configuration of tree species to effectively prevent and control atmospheric pollution.

关键词： Biogenic volatile organic compounds Pinus tabuliformis Emission rate Monoterpenes

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：