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烤烟连作对根际与非根际土壤养分及其生态化学计量特征的影响

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干旱区资源与环境 2024年第10期38卷 154-165页

作者：汤宏王建伟曾掌权刘伦沛阮运飞梁春华冷丽娟凯里学院理学院凯里556011 广西蚕桑生态学与智能化技术应用重点实验室广西现代蚕桑丝绸协同创新中心微生物及植物资源开发利用广西高校重点实验室河池学院化学与生物工程学院河池546300 湖南省林业科学院湖南衡山森林生态系统定位观测研究站长沙410004

文中探讨贵州省麻江县烟区(研究区)烤烟连作对根际与非根际土壤养分及其生态化学计量特征的影响。通过野外实地调查采样与室内分析相结合,对研究区不同连作年限(0、1、2、3、5和9a)和非植烟区(对照区)的土壤进行了测定分析,研究了土壤p... 详细信息

文中探讨贵州省麻江县烟区(研究区)烤烟连作对根际与非根际土壤养分及其生态化学计量特征的影响。通过野外实地调查采样与室内分析相结合,对研究区不同连作年限(0、1、2、3、5和9a)和非植烟区(对照区)的土壤进行了测定分析,研究了土壤pH、有机质(SOM)、全氮(TN)、全磷(TP)和全钾(TK)的含量及其生态化学计量特征。结果表明,随连作年限的增加,烟田SOM、TN呈增加的变化趋势,而TP、TK和pH分别呈波动式增加、降低和降低;同一植烟年限,根际土壤养分含量一般要高于非根际,非根际一般要高于对照区;对照区土壤养分含量呈增加的趋势。与C0(正茬)相比,除TK外,而其他养分均有增加的趋势,根际和非根际土壤C/N无明显差异,而其他计量比值波动式增加。SOC和TN显著或极显著影响根际与非根际土壤的化学计量比;SOC与TN(除对P/K外)及TP对非植烟区土壤生态化学计量比有类似的影响。随连作年限的增加,出现养分间的比例失衡和土壤酸化,钾可能是研究区连作烤烟土壤中的限制性养分,同时应注意氮素的供应;土壤生态化学计量比主要受控于土壤TN、TP和TK及SOC,并与其变化幅度密切相关。

关键词：烤烟连作根际土壤非根际土壤土壤养分生态化学计量比

Carbon storage in evergreen broad-leaf forests in mid-subtropical region of China at four succession stages

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Journal of Forestry Research 2013年第4期24卷 677-682页

作者： zeng zhangquan WANG Silong ZHANG Canming GONG Chao HU Qing Huitong Experimental Station of Forest Ecology State Key Laboratory of Forest and Soil EcologyInstitute of Applied EcologyChinese Academy of Sciences Huitong National Research Station of Forest Ecosystem Graduate School of Chinese Academy of Sci- ences Hunan Academy of Forestry Hengshan Station of Forest Ecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

To better understand the effect of forest succession on carbon sequestration, we investigated carbon stock and allocation of evergreen broadleaf forest, a major zonal forest in subtropical China. We sought to quantify the carbon sequestration potential. We sampled four forest types, shrub （SR）, pine （Pinus massoniana） forest （PF）, pin~ and broadleaf mixed forest （Mr） and evergreen broadleaf forest （BF）. A regression equation was constructed using tree height and diameter at breast height （DBH） and elements of total tree biomass. The equation was subse- quently utilized to estimate tree carbon storage. The carbon storage of understory, litter, and soil was also estimated.

关键词： Biomass carbon Carbon allocation Carbon sequestration Soil organic carbon China subtropical forest

Soil microbial activity and nutrients of evergreen broad-leaf forests in mid-subtropical region of China

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Journal of Forestry Research 2015年第3期26卷 673-678页

作者： zhangquan zeng Silong Wang Canming Zhang Hong Tang Xiquan Li Zijian Wu Jia Luo Hunan Academy of Forestry Hengshan Station of Forest Ecology Huitong Experimental Station of Forest Ecology State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences Huitong National Research Station of Forest Ecosystem College of Environment and Life Science Kaili University

To better understand the effects of forest suc- cession on soil microbial activity, a comparison of soil microbial properties and nutrients was conducted between three forest types representing a natural forest succession chronosequence. The study compared a pine （Pinus mas- soniana） forest （PF）, a pine and broadleaf mixed forest （MF） and an evergreen broadleaf forest （BF）, in the Yingzuijie Biosphere Reserve, Hunan Province, China. Results showed that soil nutrients in the MF and BF plots were higher than in the PF plots. The range in microbial biomass carbon followed a similar pattem with Be havingthe greatest values, 522-1022 mg kg-1, followed by Mr 368-569 mg kg-1, and finally, PF 193--449 mg kg-1. Soil nutrients were more strongly correlated with microbial biomass carbon than basal respiration or metabolic quo- tient. Overall, forest succession in the study site improved soil microbial properties and soil fertility, which in turn can increase primary productivity and carbon sequestration.

关键词： Keywords qCO2 Soil microbial biomass C Soil nutrient

连作烤烟土壤特征及连作障碍防控技术研究进展

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黑龙江农业科学 2024年第8期 109-117页

作者：汤宏王建伟曾掌权刘伦沛阮运飞梁春华冷丽娟凯里学院理学院贵州凯里556011 河池学院化学与生物工程学院/广西蚕桑生态学与智能化技术应用重点实验室/广西现代蚕桑丝绸协同创新中心/微生物及植物资源开发利用广西高校重点实验室广西河池546300 湖南省林业科学院/湖南衡山森林生态系统定位观测研究站湖南长沙410004

为深入阐明烤烟连作障碍的发生机制和科学选择综合防控措施,以期最大限度消减烤烟连作障碍,实现我国烤烟种植业的绿色、高效和可持续发展。从连作烤烟土壤理化性状特征、连作烤烟土壤酶活性特征、连作烤烟土壤化感物质变化特征、连作烤... 详细信息

为深入阐明烤烟连作障碍的发生机制和科学选择综合防控措施,以期最大限度消减烤烟连作障碍,实现我国烤烟种植业的绿色、高效和可持续发展。从连作烤烟土壤理化性状特征、连作烤烟土壤酶活性特征、连作烤烟土壤化感物质变化特征、连作烤烟土壤微生物群落结构和多样性变化特征等方面综述了连作烤烟土壤的特征。从培育耐连作烤烟抗性品种、优化种植制度、合理施用不同种类肥料制剂、连作土壤消毒和生物防治等方面,总结了当前我国烤烟连作障碍的防控措施,并对今后烤烟连作障碍的研究方向及防控技术最新发展方向进行了展望。

关键词：烤烟连作障碍防控技术连作土壤特征

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Biomass Characteristics of the Arbor Layer in Different Stands of the Evergreen Broad-Leaved Forest

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Journal of Landscape Research 2019年第3期11卷 105-106,109页

作者： zeng zhangquan TANG Hong LI Minghong YANG Rui ZHANG Canming WANG Ying zeng Xiahui Hengshan Research Station of Forest Ecosystem Hunan Academy of Forestry Changsha Hunan 410004 China School of Life and Health Science Kaili University Kaili Guizhou 556011 China Hunan Hengshan National Nature Reserve Administration Hengyang Hunan 421999 China Water Resources Research & Development Center Changsha Hunan 410013 China School of Science Central South University of Forestry and Technology Changsha Hunan 410004 China

In this paper, the Pinus massoniana forest in the early stage of succession, the coniferous broad-leaved mixed forest in the middle stage of succession, and the evergreen broad-leaved forest in the late stage of succession were studied, and the biomass and its spatial distribution characteristics of the tree layer in different succession stages of the ecosystem were discussed. The results showed that the biomass of the arbor layer was the highest in the evergreen broad-leaved forest, which was 292.51 t/ hm2, followed by the coniferous and broad-leaved mixed forest, which was 206.87 t/hm2, and the Pinus massoniana forest, which was 171.76 t/hm2. The biomass of trunks accounted for the largest proportion in the total biomass of the arbor layer, which reduced from the Pinus massoniana forest to the evergreen broad-leaved forest. The proportion of the biomass of roots in the total biomass of the arbor layer increased from the Pinus massoniana forest to the evergreen broad-leaved forest. The biomass of the diameter class above 20 cm in the Pinus massoniana forest, the coniferous and broad-leaved mixed forest and the evergreen broad-leaved forest accounted for a large proportion of total biomass.

关键词： Evergreen broad-leaved forest Biomass of the arbor layer Mid-subtropics Succession stage

Woody Debris Storage of Evergreen Broad-leaf Forest

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Meteorological and Environmental Research 2014年第8期5卷 16-19页

作者： zeng zhangquan Wang Silong Zhang Canming Wu Zijian Li Xiquan Hunan Academy of Forestry Hengshan Research Station of Forest Ecosystem Huitong Experimental Station of Forest Ecology State Key Laboratory of Forest and Soil EcologyInstitute of Applied EcologyChinese Academy of Sciences Huitong National Research Station of Forest Ecosystem

In Yingzuijie National Nature Reserve, Pinus massoniana forest, mixed broadleaf-coniferous forest and evergreen broad-leaf forest were investigated to study the changing characteristics of woody debris （WD） during various succession stages o1 evergreen broad-leaf forest. The results showed that during various succession stages of evergreen broad-leaf forest in Yingzuijie National Nature Reserve, WD storage of each forest ranged from 1.26 to 8.82 t/hm^2, with the order of P. massoniana forest 〈 mixed broadleaf-coniferous forest 〈 evergreen broad-leaf forest, that is, it increased from early to late stages of the succession. At different succession stages, coarse woody debris （CWD） storage was 2 -9 times more than fine woody debris （FWD） storage, revealing that CWD was dominant in WD of each forest. CWD biomass accounted for 0.66% -2.21% of arbor biomass, so the forests were at the developmental stage.

关键词： Woody debris Evergreen broad-leaf forest Middle subtropics Succession stages China

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无人机影像树冠信息提取研究

中南林业科技大学学报 2020年第8期40卷 75-82页

作者：曾霞辉王颖曾掌权周璀中南林业科技大学林学院湖南长沙410004 湖南汽车工程职业学院湖南株洲4120001 湖南省林业科学院湖南长沙410004

【目的】树冠是林木长势监测、树种识别、蓄积量估测等森林调查中的重要森林参数,对森林资源调查和生态研究等具有重要意义,相比于传统的人工实地调查的方法,通过无人机影像提取树冠信息,具有高效、准确和低成本等优势。【方法】以湖南... 详细信息

【目的】树冠是林木长势监测、树种识别、蓄积量估测等森林调查中的重要森林参数,对森林资源调查和生态研究等具有重要意义,相比于传统的人工实地调查的方法,通过无人机影像提取树冠信息,具有高效、准确和低成本等优势。【方法】以湖南衡山森林生态系统定位观测研究站实验样地为研究对象,以无人机影像为数据源,采用阈值法和K邻近法,分别对正射影像和冠层高度模型进行图像二值化,取其交集得到树冠区域图;利用数学形态学开闭重建滤波对树冠区域图进行去噪处理,有效平滑影像,避免影像对象边缘轮廓偏移;采用局部最大值法和最大类间方差法进行前景背景标记,根据影像标记修正梯度图像;利用分水岭分割算法提取树冠信息。【结果】在树冠区域提取中,基于阈值法和K邻近算法成功分割出树冠区域与背景区域,确定树冠分割范围。通过数学形态学滤波,有效地去除了由噪声及树冠内部的纹理信息所造成的伪局部极值,减少了分水岭分割算法的过分割现象,同时保护了树冠边缘轮廓及其位置信息。【结论】单木尺度上,树冠信息提取的F测度为75.98%;样地尺度上,提取的树冠面积相对误差为13.3%。基于无人机影像提取树冠信息的方法是可行的,能够快速准确地提取较高郁闭度林分的树冠信息。

关键词：无人机影像树冠信息分水岭算法形态学

Comparative Study on Different Methods for Prediction of Thermal Insulation Performance of Thermal Barrier Coating Used on Turbine Blades

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Journal of Thermal Science 2024年第1期33卷 172-189页

作者： ZHANG Zhixin zeng Wu ZHANG Xiaodong zeng Yuntao Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

As turbine inlet temperature gets higher and higher,thermal barrier coating(TBC) is more and more widely used in turbine *** turbine blades with TBC,it is of great significance to evaluate the temperature distribution of its substrate metal quickly and accurately,especially during the design *** different degrees of simplification such as whether to consider the change of the geometric size of the fluid domain by TBC and whether to consider the planar heat conduction in TBC,three different methods used in conjugate heat transfer(CHT) simulation to model the TBC of the turbine blades have been developed and widely used by ***,little research has been conducted to investigate the influence of the three methods on the temperature distribution of turbine *** fill this gap,three geometric models were *** are a solid conduction model with a substrate metal layer and a TBC layer,a transonic turbine vane with internal cooling and TBC,and a plate cylindrical film hole cooling model with *** methods were used in these geometric models and their differences were carefully analyzed and *** result shows that for the conduction model used in this paper,with the same TBC surface temperature distribution,the difference between the three methods is very small and can be *** a transonic turbine vane with internal cooling,regarding the local maximum temperature of the substrate-TBC interface,the largest difference between the method in which TBC is considered as a thermal resistance or a virtual layer of cells and the method in which three-dimensional heat conduction equation of TBC is solved occurs at the trailing *** difference near the leading edge is below *** employed to the film cooling model,the difference of the laterally averaged temperature of the substrate-TBC interface can be 8 K which is mainly due to the change of the length to diameter ratio of the film cooling hole by *** the substrate

关键词： turbine blade thermal barrier coating conjugate heat transfer film cooling hole

Nested Saturated Control of Uncertain Complex Cascade Systems Using Mixed Saturation Levels

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1163-1174页

作者： Meng Li Zhigang zeng Wuhan National Laboratory for Optoelectronics Wuhan 430074 School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

This study addresses the problem of global asymptotic stability for uncertain complex cascade systems composed of multiple integrator systems and non-strict feedforward nonlinear systems. To tackle the complexity inherent in such structures, a novel nested saturated control design is proposed that incorporates both constant saturation levels and state-dependent saturation levels. Specifically, a modified differentiable saturation function is proposed to facilitate the saturation reduction analysis of the uncertain complex cascade systems under the presence of mixed saturation levels. In addition, the design of modified differentiable saturation function will help to construct a hierarchical global convergence strategy to improve the robustness of control design scheme. Through calculation of relevant inequalities, time derivative of boundary surface and simple Lyapunov function,saturation reduction analysis and convergence analysis are carried out, and then a set of explicit parameter conditions are provided to ensure global asymptotic stability in the closed-loop systems. Finally, a simplified system of the mechanical model is presented to validate the effectiveness of the proposed method.

关键词： method saturation differentiable