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湖北省巴东县古树资源组成及其空间分布特征研究

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中国园林 2024年第5期40卷 138-144页

作者：王沛然游桂璇诸葛名名达良俊胡远东东北林业大学园林学院哈尔滨150040 西安建筑科技大学交叉院干旱区与半干旱区生态科学与工程研究院西安710055 华东师范大学上海市城市化生态过程与生态恢复重点实验室华东师范大学上海崇明生态研究院生态保育与恢复中心华东师范大学自然资源部大都市区国士空间生态修复工程技术创新中心东北林业大学黑龙江省园林植物种质资源开发与景观生态修复重点实验室

古树是全球生物多样性的重要组成部分,也是地方文化的重要载体。在全球生物多样性不断丧失尤其是古树资源持续减少的背景下,研究现存古树资源的组成和空间分布特征对古树的保育和生物多样性维持具有重要意义,同时为地区发展规划提供物... 详细信息

古树是全球生物多样性的重要组成部分,也是地方文化的重要载体。在全球生物多样性不断丧失尤其是古树资源持续减少的背景下,研究现存古树资源的组成和空间分布特征对古树的保育和生物多样性维持具有重要意义,同时为地区发展规划提供物种资源。以中国典型少数民族聚居地湖北省巴东县的古树资源为研究对象,结合野外调查和历史文献查阅,分析了巴东县古树的物种多样性、空间分布格局及其影响因素,探讨了巴东县古树保护面临的挑战与策略。结果表明,共记录古树2192株,隶属41科85属121种,所含物种数量较多的是壳斗科、松科、蔷薇科、木兰科和樟科,地理分布区系整体呈现由热带向温带过渡的特点;优势物种包括核桃、银杏和油杉;包含国家级保护物种17种;三级古树的个体数和物种数均超过一级和二级古树;古树胸径主要介于40~100cm,冠幅集中于10~17m,树高大多为15~25m;不同乡镇内分布的古树数量和物种数的差异显著,且大多分布在林地、耕地和未利用土地内。巴东县古树保护总体较好,95%以上的古树长势良好;海拔高度、坡度、人口密度、土地利用方式和文化习俗是影响巴东县古树资源组成和分布的主要因素;分级保护、分类保护、环境保护教育和差异性保护性有利于古树资源的留存和合理利用。

关键词：园林植物古树资源物种多样性分布格局留存机制巴东县

The spatial-temporal pattern and influencing factors of negative air ions in urban forests, Shanghai, China

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Journal of Forestry Research 2014年第4期25卷 847-856页

作者： Hong Liang Xiaoshuang Chen Junguang Yin liangjun da Department of Environmental Science East China Normal University Tiantong Forest Ecosystem National Research Station and Shanghai Key Laboratory for Ecology of Urbanization Process and Eco-restoration College of Landscape Architecture and Forestry Qingdao Agricultural University Kunshan Municipal Environmental Protection Bureau

Negative air ions are natural components of the air we breathe Forests are the main continuous natural source of negative air ions （NAI）. The spatio-temporal patterns of negative air ions were explored in Shanghai, based on monthly monitoring in 15 parks from March 2009 to February 2010. In each park, sampling sites were selected in forests and open spaces. The annual variation in negative air ion concentrations （NAIC） showed peak values from June to October and minimum values from December to January. NAIC were highest in summer and autumn, intermediate in spring, and lowest in winter. During spring and summer, NAIC in open spaces were significantly higher in rural areas than those in suburban areas. However, there were no significant differences in NAIC at forest sites among seasons. For open spaces, total suspended particles （TSP） were the dominant determining factor of NAIC in sum- mer, and air temperature and air humidity were the dominant determining factors of NAIC in spring, which were tightly correlated with Shanghai＇s ongoing urbanization and its impacts on the environment. R is suggested that urbanization could induce variation in NAIC along the urban-rural gradient, but that may not change the temporal variation pattern. Fur- thermore, the effects of urbanization on NAIC were limited in non-vegetated or less-vegetated sites, such as open spaces, but not in well-vegetated areas, such as urban forests. Therefore, we suggest that urban greening, especially urban forest, has significant resistance to theeffect of urbanization on NAIC.

关键词： negative air ion concentration spatial-temporal pattern urbanization urban ecosystem urban greening

Impacts of Ice-Ocean Stress on the Subpolar Southern Ocean:Role of the Ocean Surface Current

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Advances in Atmospheric Sciences 2024年第2期41卷 293-309页

作者： Yang WU Zhaomin WANG Chengyan LIU liangjun YAN School of Information Engineering Nanjing Xiaozhuang UniversityNanjing 211171China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China College of Oceanography Hohai UniversityNanjing 210098China

The mechanical influences involved in the interaction between the Antarctic sea ice and ocean surface current(OSC)on the subpolar Southern Ocean have been systematically investigated for the first time by conducting two simulations that include and exclude the OSC in the calculation of the ice-ocean stress(IOS), using an eddy-permitting coupled ocean-sea ice global model. By comparing the results of these two experiments, significant increases of 5%, 27%, and 24%, were found in the subpolar Southern Ocean when excluding the OSC in the IOS calculation for the ocean surface stress,upwelling, and downwelling, respectively. Excluding the OSC in the IOS calculation also visibly strengthens the total mechanical energy input to the OSC by about 16%, and increases the eddy kinetic energy and mean kinetic energy by about38% and 12%, respectively. Moreover, the response of the meridional overturning circulation in the Southern Ocean yields respective increases of about 16% and 15% for the upper and lower branches;and the subpolar gyres are also found to considerably intensify, by about 12%, 11%, and 11% in the Weddell Gyre, the Ross Gyre, and the Australian-Antarctic Gyre, respectively. The strengthened ocean circulations and Ekman pumping result in a warmer sea surface temperature(SST), and hence an incremental surface heat loss. The increased sea ice drift and warm SST lead to an expansion of the sea ice area and a reduction of sea ice volume. These results emphasize the importance of OSCs in the air-sea-ice interactions on the global ocean circulations and the mass balance of Antarctic ice shelves, and this component may become more significant as the rapid change of Antarctic sea ice.

关键词： subpolar Southern Ocean Antarctic sea ice ice-ocean stress air-sea-ice-ocean interaction ocean surface current MITgcm-ECCO2

Vegetation classification of East China with multi-temporal NOAA-AVHRR data

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Frontiers in Biology 2006年第3期1卷 303-309页

作者： LI Junxiang da liangjun WANG Yujie SONG Yongchang Department of Environmental Science East China Normal UniversityShanghai 200062China

East China lies in the subtropical monsoon cli-matic zone and is dominated by subtropical evergreen broad-leaved forests,a unique vegetation type mainly dis-tributed in East Asia with the largest distribution in *** is important to be able to monitor and estimate forest biomass and production,regional carbon storage,and global climate change impacts on these important vegetation *** this paper,we used coarse resolution remote sensing data to identify the vegetation types in East China and developed a map of the spatial distribution of vegetation types in this *** maximum normalized difference vegeta-tion index(NDVI)composite images(acquisition time span of 7 months from February to August),which were derived from 10 days National Oceanographic and Atmospheric Administration(NOAA)Advanced Very High Resolution Radiometer(AVHRR)channel 1 and channel 2 observa-tions,an unsupervised classification method,and the ISOdaTA algorithm were employed to identify the vegeta-tion *** reduce the dimensions of the dataset resulted in a total of 28 spectral clusters of land-cover of which two clusters were urban/bare soil and water,the images were processed using principal component analysis(PCA).The 26 remaining spectral clusters were merged into six vegeta-tion types using the Chinese vegetation taxonomy system:evergreen broad-leaved forest,coniferous forest,bamboo forest,shrub-grass,aquatic vegetation,and agricultural *** spatial distribution and areal extent for the coniferous forests,shrub-grass,evergreen broad-leaved for-ests,and agricultural vegetation were calculated and com-pared with the Vegetation Atlas of China at a 1:1,000,000 *** spatial accuracy and the area accuracy for conif-erous forests,shrub-grass,evergreen broad-leaved forests,and agricultural vegetation were 79.2%,91.3%,68.2%and 95.9%and 92.1%,95.9%,63.8%and 90.5%,*** spatial accuracy and area accuracy of the bamboo forest were 28.7%and 96.5%,respectively

关键词： vegetation classification remote sensing NDVI principal component analysis East China

The biomass and aboveground net primary productivity of Schima superba-Castanopsis carlesii forests in east China

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Science China(Life Sciences) 2010年第7期53卷 811-821页

作者： YANG TongHui SONG Kun da liangjun LI XiuPeng WU JianPing School of Resources and Environment Science East China Normal UniversityShanghai 200062China Ningbo Academy of Agricultural Science Ningbo 315040China Ningbo Technology Extension Center for Forestry and Specialty Forest Products Ningbo 315012China

The biomass and productivity of Schima superba-Castanopsis carlesii forests in Tiantong,Zhejiang Province,were determined using overlapping quadrants and stem *** total community biomass was(225.3±30.1) t hm-2,of which the aboveground parts accounted for 72.0% and the underground parts accounted for 28.0%.About 87.2% of biomass existed in the tree *** resprouting biomass was small,of which over 95.0% occurred in the shrub *** productivity of the aboveground parts of the community was(386.8±98.9) g m-2a-1,in which more than 96.0% was present at the tree *** trunk's contribution to productivity was the greatest,while that of leaves was the *** China,the community biomass of subtropical evergreen broadleaved forests differs significantly with the age of the *** community biomass of the 52-year-old *** forests in this study was lower than the average biomass of subtropical evergreen broadleaved forests in China,and was lower than the biomass of other subtropical evergreen broadleaved forests elsewhere in the ***,its productivity was lower than the model estimate,indicating that without disturbance,this community has great developmental potential in terms of community biomass and productivity.

关键词： evergreen broadleaved forest community biomass net primary productivity distribution pattern Schima superba-Castanopsis carlesii community

Effects of the sand content of muddy water content on one-dimensional vertical infiltration characteristics and dense layer formation characteristics

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 172-179页

作者： Shouxuan Kang liangjun Fei Yun Zhong Lihua Liu State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an 710048China Institute of Water Resources and Hydro-electric Engineering Xi’an University of TechnologyXi’an 710048China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002HubeiChina School of Water Conservancy and Hydroelectric Power Hebei University of EngineeringHandan 056038HebeiChina

Muddy water irrigation,an effective water-saving irrigation method,has been widely used in the Yellow River Basin in *** investigate the effect of sand content on water infiltration and dense layer formation under one-dimensional vertical infiltration of muddy water,muddy water infiltration experiments were performed in the laboratory,and five sand contents of muddy water(S=0%,3%,6%,9%,and 12%)were *** were established to describe the relationship between the cumulative infiltration amount[I(t)]and the infiltration duration(t);the relationship among the migration distance of the wetting front(Z),S,and t;the thickness of the sedimentary layer[H(t)];and the relationship between S and *** results revealed that I(t)and Z decreased significantly with the increase of sand contents,while H(t)increased significantly with the increase of sand contents.I(t)and Z were in the range of 7 cm and 20 cm for each treatment,*** variation in I(t)with t fitted Kostiakov and Philip models,and the coefficients of determination were all greater than *** the increase in S,the infiltration coefficient gradually decreased,the infiltration index gradually increased,and the sorptivity gradually *** particle composition of the sedimentary layer was similar to that of the argillaceous sediment,and the content of particles with a size of less than 2 mm in the sedimentary layer was lower than that of the argillaceous *** with the original soil,the content of particles with a size of less than 0.05 mm and physical clay particles(diameter less than 0.01 mm)in the soil with an infiltration depth of 0-2 cm *** retention layer was from the topsoil to the infiltration depth of approximately 2 *** study can provide a scientific basis for further research on soil infiltration mechanisms under muddy water.

关键词： muddy water sand content dense layer cumulative infiltration wetting front transport deposit layer thickness

A review of inorganic particles synthesized through electrical discharge in different dielectric media: from devices, structures and components to applications

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Frontiers of Materials Science 2024年第2期18卷 1-35页

作者： Yifan Liu Guilu Qin liangjun Yin Xian Jian Xianglong Li School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

Size effects and compositions constitute new properties for inorganic particles in different application *** physical method has recently attracted more attention in the preparation of inorganic ***,a low-cost,eco-friendly,simple-operating,and time-saving technique,named electrical discharge,is reviewed in relation to developments from the nature of this technique in different dielectric media to the practical experience in controlling the main processing parameters,apparatuses,types of discharge,from the various structures and components to the wide *** development of the electrical discharge technique will play an important role in improving the technology to prepare superfine inorganic particles with high ***,electrical discharge contributes to easily mixing solid materials from the atomic scale to several micrometers with different ***,metal oxides or doping materials are accessible as the dielectric medium is *** some excellent advantages,new inorganic particles exploited through the electrical discharge method will promise to be the most rewarding in some potential applications.

关键词： electrical discharge gas/liquid-phase dielectric medium inorganic particle sizeandcomposition application

AP assembled on ultrafine aluminum particle and its application to NEPE propellant

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Defence Technology（防务技术） 2024年第6期36卷 20-29页

作者： Huixin Wang Qiang Li Hui Ren liangjun Xie Tingting Liu Zhihong Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Inner Mongolia Institute of Synthetic Chemicals Hohhot 010010China

Coating modification is an important way to enhance the reactivity of aluminum *** this paper,ammonium perchlorate and aluminum powder were assembled into energetic microunits by liquid deposition *** particles with AP as shell and ultrafine aluminum powder as the core(Al@AP)were *** micromorphology results show that the coated particles are about 5μm,and the coating layer is evenly distributed on the outer surface of aluminum powder,indicating a complete *** energetic microunits were implanted into the nitrate ester plasticizing adhesive system(NEPE)as solid phase *** effect of filler on the rheological properties,safety,mechanical properties,thermal reaction and energy properties of the system was analyzed by comparing with the raw aluminum *** test results show that the rheological properties,mechanical properties and pressure index of NEPE containing system Al@AP meets the requirements of solid propellant *** with Al based propellant,the mechanical sensitivity and thermal sensitivity are decreased,the safety is better,and the explosion heat of the propellant is increased by 7.8%.The engine test shows that the specific impulse is increased by 1.2 ***@AP can improve the energy output and safety of NEPE propellant,and has potential application prospects in high-energy propellants.

关键词： Aluminum powder Coating NEPE propellant Energy output Applied research

Structure and defect dual-engineering of cobalt oxides for lowtemperature Zn-air batteries

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Nano Research 2024年第5期17卷 4108-4117页

作者： Hang Lei Zhuowen Huangfu liangjun Chen Xuelin Yang Zilong Wang Wenjie Mai Hubei Provincial Collaborative Innovation Center for New Energy Microgrid College of Electrical Engineering&New EnergyChina Three Gorges UniversityYichang 443002China Siyuan Laboratory Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy MaterialsDepartment of PhysicsJinan UniversityGuangzhou 510632China

The exploration of bifunctional electrocatalysts with high catalytic activity and long-term durability for low-temperature Zn-air batteries(ZABs)is an ongoing ***,quintet-shelled hollow spheres,P-doped multi-layer Co_(3)O_(4)(PM-Co_(3)O_(4)),with enriched oxygen vacancies are prepared by thermally induced mass relocation and a simple phosphating *** advanced characterizations reveal P anion-induced effects on internal electronic structure and local coordination *** finite element method elucidates that the complex multi-layer spherical nanostructure is conducive to the transport and diffusion of OH-and O_(2).Benefiting from its unique structural features and abundant oxygen vacancies,the well-designed PM-Co_(3)O_(4) presents small reversible oxygen overpotential for catalyzing oxygen reduction/evolution ***,the fabricated low-temperature ZABs based on PM-Co_(3)O_(4) as air-cathode exhibit high power density(20.8 mW·cm^(-2))and long-term stability(over 600 cycles)at the ultra-low temperature of-40℃,outperforming state-of-art Pt/C+IrO_(2)-based ***,the dynamic evolution mechanism of cobalt oxide catalysts during ZAB operation is *** work provides a guideline to design efficient electrocatalysts with regulated electronic configurations and exquisite nano-/microstructures for ZABs under extreme working conditions.

关键词： Zn-air batteries electrocatalysts low temperature hollow spheres oxygen vacancies