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Journal of Geographical Sciences 2025年第1期 39-64页

作者： HE Chenyang WANG Yanjiao YAN Feng LU Qi School of Ecological and environmental Science East China Normal University Institute of Ecological conservation and Restoration Chinese Academy of Forestry National Climate Center China Meteorological Administration

Water use efficiency （WUE）,as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ***,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain *** study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–*** indicated an annual mean WUE of 0.8088 gC/mm·m2across the plateau,with a spatial gradient reflecting decrease from the southeast toward the *** manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,***,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of *** factors accounted for 70.79%of the variability in *** leaf area index and temperature served as the major driving forces of WUE variation.

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Relationship between types of urban forest and PM_(2.5) capture at three growth stages of leaves

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Journal of environmental Sciences 2015年第1期27卷 33-41页

作者： Thithanhthao Nguyen Xinxiao Yu Zhenming Zhang Mengmeng Liu Xuhui Liu College of Soil and Water conservation Beijing Forestry University Science and Technology department College of Nature conservation Beijing Forestry University

Particulate matter diameter ≤ 2.5 μm（PM2.5） causes direct harm to human health. Finding forms of urban forest systems that with the ability to reduce the amount of particulate matter in air effectively is the aim of this study. Five commonly cultivated kinds of urban forest types were studied in Beijing city at three stages of leaf growth. Results show that the urban forest system is capable of storing and capturing dust from the air. The types of shrubs and broadleaf trees that have the ability to capture PM2.5from the air are most effective when leaves have fully developed. In the leafless season, the conifer and mixed tree types are the most effective in removing dust from the air. For all kinds of forest types and stages of leaf growth, the PM2.5concentration is highest in the morning but lower in the afternoon and evening. Grassland cannot control particles suspended in the air,but can reduce dust pollution caused by dust from the ground blown by the wind back into the air.

关键词： Particulate matter PM2.5 Type of urban forest Growth stages of leaves

Spatio-temporal analysis of flowering using Li DAR topography

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Journal of Geographical Sciences 2017年第1期27卷 62-78页

作者： HART Samantha MIKHAILOVA Elena POST Christopher Mc MILLAN Patrick SHARP Julia BRIDGES William department of forestry and environmental conservation Clemson University SC 29634 USA department of Mathematical Sciences Clemson University SC 29634 USA

Spatio-temporal patterns of flowering in forest ecosystems are hard to quantify and monitor. The objectives of this study were to investigate spatio-temporal patterns（e.g. soilssimple slope classesslope aspectand flow accumulation） of flowering around Lake IssaqueenaSouth Carolina（SCUSA） using plant-flowering database collected with GPS- enabled camera（stored in Picasa 3 web albums and project website） on a monthly basis in 2012 and Li DAR-based topography. Pacolet fine sandy loam had the most flowering plantsfollowed by Madison sandy loamboth dominant soil types around the lake. Most flowering plants were on moderately steep（17%–30%） and gently sloping（4%–8%） slopes. Most flowering plants were on west（247.5°–292.5°）southwest（202.5°–247.5°）and northwest（292.5°–337.5°） aspects. Most flowering plants were associated with minimum and maximum flows within the landscape. Chi-square tests indicated differences in the distributions of the proportions of flowering plants were significant by soil typeslopeaspectand flow accumulation for each month（February-November）for all months（overall）and across months. The Chi-square test on area-normalized data indicated significant differences for all months and individual differences by each month with some months not statistically significant. Cluster analysis on flowering counts for nine plant families with the most flowering counts indicated no unique separation by clusterbut implied that the majority of these families were flowering on strongly sloping（9%–16%） slopeson southwest（202.5°–247.5°） aspectsand low flow accumulation（0–200）. Presented methodology can serve as a template for future efforts to quantify spatio-temporal patterns of flowering and other phenological events.

关键词： aspect flow accumulation Geographic Information Systems(GIS) phenology soils

Influencing factors of disinfection byproducts formation during chloramination of Cyclops metabolite solutions

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Journal of environmental Sciences 2014年第3期26卷 575-580页

作者： Xingbin Sun Lei Sun Ying Lu Jing Zhang Kejing Wang department of environmental Science Northeast Forestry University

Effects of reaction time, chlorine dosage, pH and temperature on the formation of disinfection byproducts （DBPs）, were investigated during the chloramination of Cyclops metabolite solutions. The results showed that some species of DBPs like trichloromethane （TCM）, dichloroacetic acid （DCAA） and trichloroacetic acid （TCAA） could accumulate to their respective stable values with a progressive elevation in reaction time and monochloramine concentration. And 1,1,1-2-trichloropropanone （1,1,1- TCP） content decreased correspondingly with a continuous increase of reaction time. The amounts of chloral hydrate （CH）, chloropicrin （TCNM）, 1,1,1-TCP and DCAA firstly increased and then decreased with increasing monochloramine doses. Higher temperature resulted in a decrease of CH, dichloroacetonitrile （DCAN）, 1,1-dichloropropanone （1,1-DCP）, 1,1,1-TCP, DCAA and TCAA concentration, pH affected the formation of the different DBPs distinctly. TCM accumulateded with the increase of pH under 9, and DCAA, TCAA, CH and 1,1-DCP decreased continuously with increasing pH from 5 to 10, and other DBPs had the maximum concentrations at pH 6-7.

关键词： chloramination Cyclops metabolite solutions DBPs

Impact of monoculture of poplar on rhizosphere microbial communities over time

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Pedosphere 2020年第4期30卷 487-495页

作者： Qian LU Jinchi ZHANG Lisha CHEN department of Water and Soil conservation College of ForestryNanjing Forestry UniversityNanjing 210037China

To date, research on the adverse effects of continuous cropping has focused on field crops;forest plantations, despite their very significant economic and ecological value, have received less attention. The evolution of microbial community in the rhizosphere of forest plantations, in particular, has rarely been examined. In this study, changes in the size, composition, and structure of bacterial and fungal communities in the rhizosphere of different generations of poplar (Populus deltoides) plantations were studied using real-time polymerase chain reaction (PCR) and PCR-denaturing gradient gel electrophoresis and compared with the composition of the microbial community in a bare land (control) adjacent to the plantation sites through sequencing analysis and by constructing phylogenetic trees. The numbers of bacteria and fungi increased significantly with successive poplar generations, although the increases in the two groups were not parallel. When compared with the control, the bacterial community increased greatly in the second generation, and the most significant increase occurred in the third generation. In contrast, the most significant increase in the fungal community occurred in the first generation, and the increase in the third generation was insignificant. In terms of community composition, the first generation showed little change in either community;however, the second generation showed remarkable changes in the bacterial community, and the third in the fungal community. The numbers of Gammaproteobacteria,Alphaproteobacteria, and Actinobacteria increased by 10.92%, 7.38%, and 5.46%, respectively, whereas those of Acidobacteria decreased by 18.38%in the second generation. These changes in the number and composition of microbial communities in the rhizosphere could be one of the reasons for the decline in yield and quality associated with long-term monoculture.

关键词： bacterial community continuous cropping denaturing gradient gel electrophoresis forest plantations fungal community polymerase chain reaction Populus deltoides

Variation in assimilable organic carbon formation during chlorination of Microcystis aeruginosa extracellular organic matter solutions

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Journal of environmental Sciences 2016年第7期28卷 1-6页

作者： Xingbin Sun Ting Yuan Huishan Ni Yanpeng Li Yang Hu department of environmental Science Northeast Forestry University

This study investigated the chlorination of Microcystis aeruginosa extracellular organic matter（EOM） solutions under different conditions, to determine how the metabolites produced by these organisms affect water safety and the formation of assimilable organic carbon（AOC）. The effects of chlorine dosages, coagulant dosage, reaction time and temperature on the formation of AOC were investigated during the disinfection of *** metabolite solutions. The concentration of AOC followed a decreasing and then increasing pattern with increasing temperature and reaction time. The concentration of AOC decreased and then increased with increasing chlorination dosage, followed by a slight decrease at the highest level of chlorination. However, the concentration of AOC decreased continuously with increasing coagulant dosage. The formation of AOC can be suppressed under appropriate conditions. In this study, chlorination at 4 mg/L, combined with a coagulant dose of 40 mg/L at 20°C over a reaction time of 12 hr, produced the minimum AOC.

关键词： Microcystis aeruginosa Chlorination Assimilable organic carbon(AOC)

Deposition of water-soluble inorganic ions in PM_(2.5) in a typical forestry system in Beijing,China

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Forest Ecosystems 2018年第4期5卷 486-497页

作者： Junqi Ding Xiaoxiu Lun Weifang Ma Lu Zhao Yingying Cao Fengbin Sun Renna Li College of environmental Science and Engineering Beijing Forestry University State Key Laboratory of environmental Criteria and Risk Assessment Chinese Academy of Environmental Sciences School of Soil and Water conservation Beijing Forestry University

Background: Rapid economic development in China has resulted in an increase in severe air pollution in city groups such as the Beijing-Tianjin-Hebei Metropolitan Region. PM2.5(fine particles with an aerodynamic equivalent diameter of 2.5 μm or less) is one of the most important pollutants. The deposition process is an important way of removing particles from the air. To evaluate the effect of an urban forest on atmospheric particle removal, a concentration gradient method was used to measure the deposition velocities of water-soluble inorganics in PM2.5 in two national forest parks in Beijing, China. The following eight water-soluble inorganic ions in PM2.5 were investigated: sodium, ammonium, potassium, magnesium, calcium, chloride, nitrate, and ***: Samples were taken from two sites in Beijing from the 7 th to the 15 th May, 2013. The concentrations of water-soluble inorganic ions were analyzed with ion chromatography. We used the concentration gradient technique to estimate the deposition flux and velocity. To determine the relationships between leaf traits and particle accumulation, typical leaf samples from each selected species were studied using scanning electron ***: The total deposition flux and total deposition velocity during the daytime were higher than those at *** showed the biggest deposition flux and velocity at both study sites, whereas the other ions showed different trends at each site. Result from higher proportion of coniferous to broadleaved trees, the total deposition flux of the eight ions measured in Jiufeng National Forest Park was greater than that in Olympic Forest ***: The deposition velocity was affected by meteorological conditions such as wind speed, temperature,and humidity. The deposition velocity was also influenced by tree species. The surface of plants is an important factor influencing particle deposition. The results of this study may help in assessing the effects of forestry sy

关键词： Fine particle Water-soluble inorganics Forest Dry deposition Deposition velocity

Stand development patterns of forest cover types in the natural forests of northern Baekdudaegan in South Korea

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Journal of forestry Research 2015年第2期26卷 381-390页

作者： Ji Hong Kim Guangze Jin Sang Hoon Chung department of Forest Management College of Forest and Environmental SciencesKangwon National University School of forestry Northeast Forestry University Forest Ecology Division Forest Conservation DepartmentKorea Forest Research Institute

The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South ***-eight independent forest communities were aggregated into eight forest cover types by species composition in the overstory of each forest *** forest cover types were of mixed mesophytic,‘‘others’ ’ deciduous,Quercus mongolica dominant,*** pure,Pinus densiflora–***,***,Betula ermanii,and ***–*** ecological information was organized by importance value and species diversity for each forest *** on the correlation between species diversity index and the abundance of *** plus *** for corresponding forest cover types,we compared the developmental process and approximate successional pathway between each cover *** *** forest cover type changes into the ***–*** cover type,followed by the *** dominant cover type through continuous invasion of the oak ***,the *** pure cover type would spread toward the *** dominant cover type with a mixture of various deciduous tree *** *** dominant cover type progresses through the other deciduous cover types to the mixed mesophytic cover type with diversified composition and *** the mid to lower slopes,with loamy soils and good moisture conditions,various deciduous forest types should progress,by ecological succession,toward the mixed mesophytic cover type without any further disturbance.

关键词： Baekdudaegan Forest cover type Species composition Species diversity Stand development patterns

Arbuscular mycorrhizal fungi communities associated with wild plants in a coastal ecosystem

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Journal of forestry Research 2021年第2期32卷 683-695页

作者： Jinping Wang Shilin Ma G.Geoff Wang Linhao Xu Zhiyuan Fu Juan Song Jinchi Zhang Co-Innovation Center for Sustainable forestry in Southern China Jiangsu Province Key Laboratory of Soil and Water Conservation and Ecological RestorationNanjing Forestry University159 Longpan RoadNanjing 210037JiangsuChina department of forestry and environmental conservation Clemson UniversityClemsonSC 29634USA

Arbuscular mycorrhizal fungi(AMF)form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant *** little is known about the structure and composition of AMF communities on coastal beaches of eastern *** this study,we investigated the occurrence,community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu,*** all of the local wild species were colonized by AMF except for Chenopodium album ***-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven *** was the dominant genus and Funneliformis mosseae the dominant *** colonization,spore composition and diversity of AMF were strongly related to edaphic ***(Na^(+))ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na^(+)levels and pH had a significant negative effect on AMF spore density and ***,there was a significant positive correlation between species richness and total organic *** results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.

关键词： AMF diversity Coastal beach Edaphic factors Mycorrhizal composition Wild hosts

Acoustic Characteristics of Advertisement Calls in Babina adenopleura

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Asian Herpetological Research 2015年第3期6卷 220-228页

作者： Xiaobin FANG Xia QIU Yilin ZHOU Luyi YANG Yi ZHAO Weihong ZHENG Jinsong LIU School of Life and environmental Sciences Wenzhou University School of Nature conservation Beijing Forestry University

Acoustic communication is the most important form of communication in anuran amphibians. To understand the acoustic characteristics of male Babina adenopleura, we recorded advertisement calls and analyzed their acoustic parameters during the breeding season. Male B. adenopleura produced calls with a variable number of notes（1–5）, and each note contained harmonics. Although 6% of call notes did not exhibit frequency modulation（FM）, two call note FM patterns were observed：（1） upward FM;（2） upward–downward FM. With the exception of 1- and 5- note calls, the duration of successive notes decreased monotonically. With the exception of 1 note calls, the fundamental frequency of the first note was lowest, then increased; the greatest change in the fundamental frequency was always between notes 1 and 2. The dominant frequency varied between calls. For example for the first call note the dominant frequency occurred in some cases in the first harmonic（located in the 605.320 ± 64.533 Hz frequency band）, the second harmonic（918 ± 9 Hz band）, the fourth harmonic（1712 ± 333 Hz band）, the sixth harmonic（the 2165 ± 152 Hz band）, the seventh harmonic（the 2269 ± 140 Hz band）, the eighth harmonic（the 2466 ± 15 Hz band） or the ninth harmonic（the 2636 ± 21 Hz band）. Although male B. adenopleura advertisement calls have a distinctive structure, they have similar characteristics to the calls of the music frog, B. daunchina.

关键词： anuran amphibians advertisement calls Babina adenopleura call structure