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Study on successions sequence of evergreen broad-leaved forest in Gutian Mountain of Zhejiang,Eastern China:species diversity

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Frontiers in Biology 2008年第1期3卷 45-49页

作者： zhenghua hu Mingjian YU College of Environmental Science and Engineer Nanjing University of Information Science and TechnologyNanjing 210044China College of Life Science Zhejiang UniversityHangzhou 310028China

Using the widely adopted scheme of space-for-time substitution for investigating 16 typical plots distri-buted as a pattern of contiguous grid quadrates within a sampling plot,the expressions of Shannon-Wiener index(H)for species diversity,Pielou index(J_(sw),J_(SI))for evenness and Simpson index(D)for ecological dominance are employed to investigate the species diversity(SD)of four evergreen broadleaved communities in the successions sequence within the Nature Reserve of the Gutian *** showed that in the successions process from the coniferous to the mixed coniferous-broadleaved,then to Schima superba and finally to Castanopsis eyrei forest,the arbor layer SD showed the Shannon-Wiener index(H)as 1.9670,2.4975,2.6140 and 2.4356,respectively,characterized by their rise before drop and the shrub(herb)layer SD shows the maximum to be in the mixed coniferous-broadleaved(coniferous)forest(H arriving at 2.8625(1.5334)).In the vertical structure,on the other hand,for the sequenced coniferous forest,coniferous-broad mixed forest and Castnaopsis eyrei forest,the number of SD ranges in a decreasing order from the shrub,arbor to herb layer in contrast to the SD in a decreasing order of Schima superba forest ranging from the arbor to shrub and then to herb layer,and during the succession,the herb layer exhibits the maximum range of SD change among these layers,with its variation coefficients of 0.1572,0.0806,0.0899 and 0.1884 for H,J_(SW),J_(SI) and D,in order,in sharp contrast to the minimal SD range in the shrub layer,with the corresponding figures of 0.0482,0.0385,0.0142,and 0.1553.

关键词： evergreen broad-leaved forest successions species diversity community Gutian Mountain

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Climate and Vegetation Drivers of Terrestrial Carbon Fluxes:A Global Data Synthesis

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Advances in Atmospheric Sciences 2019年第7期36卷 679-696页

作者： Shutao CHEN Jianwen ZOU zhenghua hu Yanyu LU Jiangsu Key Laboratory of Agricultural Meteorology Nanjing University of Information Science and TechnologyNanjing210044China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing210095China School of Applied Meteorology Nanjing University of Information Science and TechnologyNanjing210044China Climate Center Anhui Weather BureauHefei230031China

The terrestrial carbon(C) cycle plays an important role in global climate change, but the vegetation and environmental drivers of C fluxes are poorly understood. We established a global dataset with 1194 available data across site-years including gross primary productivity(GPP), ecosystem respiration(ER), net ecosystem productivity(NEP), and relevant environmental factors to investigate the variability in GPP, ER and NEP, as well as their covariability with climate and vegetation *** results indicated that both GPP and ER increased exponentially with the increase in mean annual temperature(MAT)for all biomes. Besides MAT, annual precipitation(AP) had a strong correlation with GPP(or ER) for non-wetland *** leaf area index(LAI) was an important factor determining C fluxes for all biomes. The variations in both GPP and ER were also associated with variations in vegetation characteristics. The model including MAT, AP and LAI explained 53%of the annual GPP variations and 48% of the annual ER variations across all biomes. The model based on MAT and LAI explained 91% of the annual GPP variations and 92.9% of the annual ER variations for the wetland sites. The effects of LAI on GPP, ER or NEP highlighted that canopy-level measurement is critical for accurately estimating ecosystem–atmosphere exchange of carbon dioxide. The present study suggests a significance of the combined effects of climate and vegetation(e.g.,LAI) drivers on C fluxes and shows that climate and LAI might influence C flux components differently in different climate regions.

关键词： net ecosystem productivity gross primary productivity ecosystem respiration controlling factors vegetation model

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A new estimate of global soil respiration from 1970 to 2008

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Chinese Science Bulletin 2013年第33期58卷 4153-4160页

作者： CHEN ShuTao huANG Yao XIE Wei ZOU JianWen LU YanYu hu zhenghua School of Environmental Science and Engineering Nanjing University of Information Science and Technology State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences College of Resources and Environmental Sciences Nanjing Agricultural University Anhui Climate Center School of Applied Meteorology Nanjing University of Information Science and Technology

土壤呼吸(R s ) 是在陆上的生态系统加重我们碳周期的理解的关键过程之一。在有在最高、最低的估计之间的 70 Pg C a1 的差别的以前的全球 R s 估计的大无常遗体。因此，现在的学习试图估计全球年度 R s 并且用包括了气候的因素(温度和... 详细信息

土壤呼吸(R s ) 是在陆上的生态系统加重我们碳周期的理解的关键过程之一。在有在最高、最低的估计之间的 70 Pg C a1 的差别的以前的全球 R s 估计的大无常遗体。因此，现在的学习试图估计全球年度 R s 并且用包括了气候的因素(温度和降水) 和表层土(020 厘米) 的一个半机械学的、以经验为主地基于的模型在全球年度 R s 调查 interannual 和空间可变性器官的碳存储。从 147 个测量地点的年度 R s 的大约 657 出版研究在这元分析被包括。气候，表面空气温度，和土壤性质上的从 1970 ～ 2008 的全球数据集合是镇定的。蒙特卡罗方法被用来宣传模拟错误到全球 R s。结果显示吝啬的年度全球 R s 是 94.4 Pg C a1，增加在粗略地从 1970 ～ 2008 的 0.04 Pg C a1 (0.04% a1 ) 。R s 率增加了从更冷，更干燥并且少些玷污充满碳的区域到更温暖、更潮湿、更充满碳的区域。最高的 R s 率出现在热带森林里，当最低的在极、荒芜的区域时。年度 R s 与全球温度异例直接相关，建议在温度的 interannual 可变性为在预言的全球 R s 的 interannual 变化负责。全球 R s 从高纬度的地区增加了到低纬度的地区。进一步的研究被建议探索在土壤呼吸和植被人物之间的关系。

关键词：土壤呼吸估计年际变化陆地生态系统蒙特卡罗方法温度距平气候因素资源丰富

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Interannual variability in soil respiration from terrestrial ecosystems in China and its response to climate change

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Science China Earth Sciences 2012年第12期55卷 2091-2098页

作者： CHEN ShuTao huANG Yao ZOU JianWen SHI YanShu LU YanYu ZHANG Wen hu zhenghua School of Environmental Science and Engineering Nanjing University oflnformation Science and TechnologyNanjing 210044China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation Nanjing Agricultural UniversityNanjing 210095China Anhui Climate Center Hefei 230031China

Soil respiration is an important process in terrestrial carbon *** terrestrial ecosystems in China, quantifying the spatiotemporal pattern of soil respiration at the regional scale is critical in providing a theoretical basis for evaluating carbon *** this study, we used an empirically based, semi-mechanistic model including climate and soil properties to estimate annual soil respiration from terrestrial ecosystems in China from 1970 to *** further analyzed the relationship between interannual variability in soil respiration and climatic factors (air temperature and precipitation).Results indicated that the distribution of annual soil respiration showed clear spatial *** highest and lowest annual soil respiration rates appeared in southeastern China and northwestern China, respectively, which was in accordance with the spatial patterns of mean annual air temperature and annual *** the mean annual air temperature in northwestern China was higher than that in some regions of northeastern china, a greater topsoil organic carbon storage in northeastern China might result in the higher annual soil respiration in this *** contrast, lower temperature, less precipitation and smaller topsoil organic carbon pool incurred the lowest annual soil respiration in northwestern *** soil respiration from terrestrial ecosystems in China varied from 4.58 to 5.19 PgCa-1 between 1970 and *** this time period, on average, annual soil respiration was estimated to be 4.83 PgCa-1 .Annual soil respiration in China accounted for 4.93%-6.01% of the global annual soil CO2 *** interannual variability in soil respiration depended on the interannual variability in precipitation and mean air *** order to reduce the uncertainty in estimating annual soil respiration at regional scale, more in situ measurements of soil respiration and relevant factors (***, soil and vegetation) should be made simultane

关键词： China soil respiration temporal variability climate

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New Discovery of Shizhushan Superlarge Wollastonite Deposit in Xinyu City, Jiangxi Province

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 1670-1671页

作者： hu zhenghua WANG Xlanguang CHEN Guohua LI Yanhong ZHAN Tlanwe CHEN Sibao LIU Shaohua CHEN Xuguang Geological Survey of Jiangxi Province Nanchang 330000 China Administration of Geological Prospecting Fund of Jiangxi Province Nanchang 330030 China China University of Geosciences Beijing 100083 China Geological Party Coal Geological Bureau of Jiangxi Province Xinyu 336600 Jiangxi China

Objective The Mengshan area of the Xinyu City, Jiangxi Province is an important wollastonite production base in China. As early as the 90s of the 20th century, more than ten medium to small-sized wollastonite deposits, such as the Yueguangshan and Caofangmiao Deposits were discovered in the outer contact zone of the Mengshan rock mass. After that, no more progress was achieved in wollastonite prospection. In 2016, the project funded by the Geological Prospecting Fund of Jiangxi Province made significant breakthroughs in the ＂General Survey of the Shizhushan Wollastonite Ore in the Yushui District and Zhangmuqiao Wollastonite Ore in Shanggao County, Xinyu City, Jiangxi Province＂ in the Mengshan area. The new discovered Shizhushan Wollastonite Deposit has a scale of 50 million tons and its resources scale far exceeds that of the Seeleys Bay Wollastonite Deposit discovered in Canada.

关键词： New Discovery of Shizhushan Superlarge Wollastonite Deposit in Xinyu City Jiangxi Province

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Effect of CeO_(2) nanoparticle sizes on catalytic performances of sulfated CeO_(2)/Al_(2)O_(3) catalyst in NH_(3)-SCR reaction

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Journal of Rare Earths 2024年第3期42卷 515-522,I0004页

作者： zhenghua hu Dongqi An Lei Zhang Xuping Wang Siyong Fang Xinyun Tian Liu Qiu Jingfang Sun Tingzhen Li Lin Dong School of Environmental and Chemical Engineering Chongqing Three Gorges UniversityChongqing404000China Key Laboratory of Water Environment Evolution and Pollution Control in the Three Gorges Reservoir Chongqing Three Gorges UniversityChongqing404000China Jiangsu Key Laboratory of Vehicle Emissions Control Center of Modern AnalysisNanjing UniversityNanjing210093China

The sulfated CeO_(2)/Al_(2)O_(3) catalysts with different sizes of CeO_(2)nanoparticles were prepared by using pure H_2O or acetic acid solution as impregnation solvent, and the influence of sizes of CeO_(2) nanoparticles on the catalytic performances of the sulfated CeO_(2)/Al_(2)O_(3) catalyst was studied. The catalytic performance tests show that the sulfated CeO_(2)/Al_(2)O_(3) catalyst using acetic acid solution as impregnation solvent has better catalytic activity and the resistance to K+poisoning than the sulfated CeO_(2)/Al_(2)O_(3) catalyst using pure H_(2)O as impregnation solvent. The excellent catalytic performances can be ascribed to the smaller sizes of CeO_(2) nanoparticles in CeO_(2)/Al_(2)O_(3) catalyst using acetic acid solution, which results in larger amount of adsorbed sulfate species, surface acid sites, surface active oxygen species and excellent redox property. These features are helpful for improving the catalytic performances of sulfated CeO_(2)/Al_(2)O_(3) catalyst using smaller amount of CeO_(2) to cut the costs.

关键词： Cerium-based catalyst Nanoscale effect NH_(3)selective catalytic reaction Sulfation process Alkali metal poisoning Rare earths

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Deactivation induced by metal sulfate over MnCeOx catalyst in NH_(3)-SCR reaction at low temperature

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Journal of Rare Earths 2024年第6期42卷 1056-1065,I0002页

作者： Qiao Xie Dongqi An Linsen Zhou Tingzhen Li zhenghua hu Menghan Chen Menglan Ma Lei Zhang Jingfang Sun Lin Dong School of Environmental and Chemical Engineering Chongqing Three Gorges UniversityChongqing404000China Key Laboratory of Water Environment Evolution and Pollution Control in the Three Gorges Reservoir Chongqing Three Gorges UniversityChongqing.404000China Jiangsu Key Laboratory of Vehicle Emissions Control Center of Modern AnalysisSchool of EnvironmentNanjing UniversityNanjing210093China Institute of Materials China Academy of Engineering PhysicsMianyang621908China

Sulfate adsorption is one of the factors that cause the poisoning of catalyst in the low-temperature NH_(3) selective catalytic reduction reaction(NH_(3)-SCR).In this paper,by controlling the co-adsorption time of SO_(2) and O_(2) at 150℃,a range of sulfated MnCeOx catalysts with different contents of metal sulfate species were prepared to reveal the influence of metal sulfate species content on the catalytic performances and reaction mechanisms at low *** catalytic activity below 250℃rapidly decreases with increasing metal sulfate species *** results of characterizations shed light on the reduction of specific surface area,Mn^(4+)and Ce^(3+)content,and redox ability of MnCeOx owing to the formation of metal sulfate *** experiments reveal that metal sulfate species preferentially absorb on MnOx domains rather than on CeO_(2) domains,and the adsorbed metal sulfate species can suppress the Eley-Rideal and the Langmuir-Hinshelwood reaction mechanisms over the sulfated *** the above results are detrimental to the activity of sulfated MnCeOx in the low-temperature NH3-SCR reaction.

关键词： NH_(3)selective catalytic reduction MnCeOx catalyst Sulfation Low-temperature activity SO_(2)poisoning Rare earths

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面向关系数据库扩展的自适应影像金字塔模型

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测绘学报 2015年第6期44卷 678-685,701页

作者：胡正华孟令奎张文武汉大学遥感信息工程学院湖北武汉430079

随着遥感技术的发展,特别是传感器分辨率的提高,影像数据量日益增长,这对高效、智能地管理海量数据提出了更高的要求,如何有效、智能地存取海量遥感数据成为当前越来越热门的话题。本文针对空间数据管理系统的发展现状,结合数据库存储... 详细信息

随着遥感技术的发展,特别是传感器分辨率的提高,影像数据量日益增长,这对高效、智能地管理海量数据提出了更高的要求,如何有效、智能地存取海量遥感数据成为当前越来越热门的话题。本文针对空间数据管理系统的发展现状,结合数据库存储、网络传输和客户端的硬件情况,从影像数据切片和影像数据的细节层次(level of detail,LOD)模型两个层面来解决遥感数据的存储问题,提出了自适应的遥感影像切片机制,以及与之相适应的LOD模型构建方法。通过试验证实,该影像管理机制能够在多种不同的数据库、网络和客户端条件下实现影像数据智能化高效存储与访问。本文的研究为高效的影像数据管理提供了可行的思路和方法,有助于在C/S架构的网络环境下实现基于数据库技术的遥感影像数据的高效存取和管理。

关键词：金字塔模型自适应分块数据库存储网络传输

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面向用户的网络计划技术分析

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南京航空航天大学学报 2000年第3期32卷 318-323页

作者：胡正华南京航空航天大学工商学院南京210016

现有的网络计划软件 ,在大型项目中的使用显得有些不便 ,尤其是作业和作业关系的输入方法。文中在分析了人类思维特点的基础上 ,提出了新型的作业和作业关系输入方法。由专业人员根据项目的工艺流程 ,把项目分解成若干作业。对于复杂项... 详细信息

现有的网络计划软件 ,在大型项目中的使用显得有些不便 ,尤其是作业和作业关系的输入方法。文中在分析了人类思维特点的基础上 ,提出了新型的作业和作业关系输入方法。由专业人员根据项目的工艺流程 ,把项目分解成若干作业。对于复杂项目 ,可以分层次分解作业。确定作业名称、作业周期 ,确定作业关系 ,并成对输入作业关系。检查并排除作业关系中可能存在的回路问题。根据网络计划技术的基本原理 ,进行作业时间计算。该方法非常直观 ,作业输入无先后次序要求 ,也不要求用户事先统计每一个作业的所有紧前作业或所有紧后作业。

关键词：网络计划技术面向用户作业关系

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浙江古田山常绿阔叶林演替序列研究:群落物种多样性

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生态学杂志 2006年第6期25卷 603-606页

作者：胡正华于明坚南京信息工程大学环境科学系南京210044 浙江大学生命科学学院杭州310028

采用较为成熟的“空间差异代替时间变化”的研究方法,应用相邻格子样方法调查了16个典型样地,利用Shannon-Wiener指数、Pielou均匀度指数、Simpson生态优势度指数计算了浙江古田山自然保护区常绿阔叶林演替序列4种群落的物种多样性。结... 详细信息

采用较为成熟的“空间差异代替时间变化”的研究方法,应用相邻格子样方法调查了16个典型样地,利用Shannon-Wiener指数、Pielou均匀度指数、Simpson生态优势度指数计算了浙江古田山自然保护区常绿阔叶林演替序列4种群落的物种多样性。结果表明,从针叶林到针阔叶混交林、木荷林和甜槠林的演替过程中,4种群落乔木层的Shannon-Wiener指数分别为1.9670、2.4975、2.6140和2.4356,呈现先增大后变小的趋势;灌木层物种多样性以针阔叶混交林最高,Shannon-Wiener指数为2.8625;针叶林的草本层Shannon-Wiener指数为1.5334,高于其它3种群落。在群落的垂直结构中,演替序列中的针叶林、针阔叶混交林、甜槠林物种多样性均表现为灌木层>乔木层>草本层,而木荷林物种多样性大小则表现为乔木层>灌木层>草本层。演替过程中,乔木层、灌木层和草本层的物种多样性的变化幅度以草本层最大,H、JSW、JSI、D的变异系数分别为0.1572、0.0806、0.0899和0.1884;灌木层变化幅度最小,其H、JSWJ、SI、D的变异系数分别为0.0482、0.0385、0.0142和0.1553。

关键词：常绿阔叶林演替物种多样性群落古田山

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