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配比施肥对柚木早期生长及叶片养分含量的影响

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西北农林科技大学学报（自然科学版） 2024年第1期52卷 71-78页

作者：赵威威周再知张青青黄桂华韩强王先棒中国林业科学研究院热带林业研究所广东广州510520 南京林业大学林学院江苏南京210037

【目的】探究不同肥料配比对柚木幼树生长及叶片养分和叶绿素含量的影响,为确定适宜的柚木施肥方案提供参考。【方法】以柚木幼林为研究对象,采用随机区组试验设计,设置5种配比施肥处理(0.25 kg/株氮磷钾复合肥+0.25 kg/株钙镁磷肥(T1)... 详细信息

【目的】探究不同肥料配比对柚木幼树生长及叶片养分和叶绿素含量的影响,为确定适宜的柚木施肥方案提供参考。【方法】以柚木幼林为研究对象,采用随机区组试验设计,设置5种配比施肥处理(0.25 kg/株氮磷钾复合肥+0.25 kg/株钙镁磷肥(T1)、0.25 kg/株钙镁磷肥+2.50 kg/株有机肥(T2)、0.25 kg/株氮磷钾复合肥+0.25 kg/株氧化镁+10.00 g/株硼肥(T3)、0.25 kg/株氮磷钾复合肥(T4)、0.25 kg/株氮磷钾复合肥+1.50 kg/株钙镁磷肥(T5)),以不施肥处理为对照(CK),分析不同施肥处理柚木幼树生长量及叶片养分和叶绿素含量的变化,运用隶属函数法对不同处理的施肥效应进行综合评价。【结果】①与CK相比,不同配比施肥处理均可以提高柚木的树高、胸径和材积平均增量,其中均以T5处理柚木的树高、胸径和材积平均增量最高,较CK分别提高了44.81%,82.02%和108.72%。②与CK相比,不同配比施肥处理柚木叶片全N、全K、交换性Ca含量均无显著变化,但叶片全P、交换性Mg含量显著提升,叶片N/P值显著降低。③与CK相比,不同配比施肥处理均可以提高柚木叶片的叶绿素a、叶绿素b和总叶绿素含量,降低叶绿素a/b值,其中T5处理叶片叶绿素a和总叶绿素含量与CK差异达显著水平。④隶属函数法评价结果显示,5种配比施肥处理的肥料效应由大到小排序为T5>T3>T2>T1>T4。【结论】5种配比施肥处理均可促进柚木叶片对钙、镁、磷营养元素的吸收与累积,加快叶绿素的合成,促进柚木幼树生长量的增加,其中0.25 kg/株氮磷钾复合肥+1.5 kg/株钙镁磷肥为最佳肥料组合。

关键词：柚木配比施肥养分累积叶绿素合成

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琼西南5年生柚木无性系生长性状遗传变异分析

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中南林业科技大学学报 2024年第5期44卷 76-83页

作者：潘栋康梁坤南周再知林明平王先棒周文龙李昆亮黄桂华中国林业科学研究院热带林业研究所国家林业和草原局热带林业重点实验室广东广州510520 海南大学林学院海南海口570228

【目的】研究柚木无性系生长性状遗传变异和年度相关性,早期选育速生优良无性系。【方法】采用6株单行小区、6次重复的完全随机区组设计,对海南省乐东县15个柚木无性系大田测定林造林后1~5 a的保存率和生长指标进行方差分析、邓肯多重... 详细信息

【目的】研究柚木无性系生长性状遗传变异和年度相关性,早期选育速生优良无性系。【方法】采用6株单行小区、6次重复的完全随机区组设计,对海南省乐东县15个柚木无性系大田测定林造林后1~5 a的保存率和生长指标进行方差分析、邓肯多重比较、遗传参数估算和相关性分析,并通过主成分分析,计算综合得分,在此基础上选出速生优良无性系。【结果】造林后5 a,柚木无性系间保存率差异显著(P<0.05),无性系保存率为61.50%~83.33%,平均保存率为73.26%,无性系7509的保存率最高,为83.33%;造林后5 a,柚木无性系间树高、胸径和单株材积均呈极显著差异(P<0.001),其平均值分别为5.29 m、7.29 cm和16.34 dm^(3),以无性系74_12最高,其树高、胸径和单株材积的平均值分别为6.12 m、9.11 cm和27.45 dm^(3);造林后1~5 a柚木无性系的树高、胸径和单株材积的变异系数分别为15.02%~19.35%、13.65%~20.14%和31.04%~41.01%,重复力分别为0.697~0.858、0.819~0.847、0.751~0.854;柚木无性系生长性状的年度相关性呈显著水平(P<0.05)。【结论】柚木无性系生长性状间存在稳定的遗传变异,有较高的遗传改良潜力;为琼西南地区筛选出柚木速生无性系74_12、7114和7509,入选无性系的树高、胸径、单株材积和保存率的平均值分别为35.77 m、8.07 cm、21.27 dm和74.61%,分别比对照提高了19.21%、23.60%、75.60%和3.40%。选择后树高、胸径和单株材积的现实增益为9.07%、10.69%和30.20%,遗传增益为7.71%、9.09%和25.67%,入选的3个无性系可作为后续柚木育种和推广的优良材料。

关键词：柚木无性系生长性状遗传变异早期评价

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Effect of slope position on leaf and fine root C,N and P stoichiometry and rhizosphere soil properties in Tectona grandis plantations

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林业研究:英文版 2023年第6期34卷 1997-2009页

作者： Qingqing Zhang zaizhi zhou Weiwei Zhao Guihua Huang Gaofeng Liu Xiaofei Li Junduo Wu Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou 510520People’s Republic of China Experimental Center of Tropical Forestry Chinese Academy of ForestryPingxiang 532600People’s Republic of China

Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation of these elements in trees and rhizosphere *** we analyzed the C,N,P content and stoichiometry in leaves,fine roots and rhizosphere soils of trees on the upper and lower slopes of a 12-year-old teak *** Kraft classification system of tree status was used to sample dominant,subdominant and mean trees at each slope *** results showed that the C,N and P contents in leaves were higher than in fine roots and rhizosphere *** lowest C/N,C/P and N/P ratios were found in rhizosphere soils,and the C/N and C/P ratios in fine roots were higher than in *** accumulation in leaves,fine roots and rhizosphere soils were significantly influenced by slope position and tree class with their interaction mainly showing a greater effect on rhizosphere *** C content and C/N ratio,fine root C and P contents,and C/N and C/P ratios all increased distinctly with declining slope *** contents of organic matter(SOM),ammonium(NH4+-N),nitrate-nitrogen(NO3--N)and available potassium(AK)in rhizosphere soils were mainly enriched on upper slopes,but exchange calcium(ECa),available phosphorus(AP),and pH were relatively *** in the C,N and P stoichiometries in trees were mainly attributed to the differences in rhizosphere soil properties.N and P contents showed significant positive linear relationships between leaf and rhizosphere soil,and C content negative linear correlation among leaves,fine roots and rhizosphere *** properties of rhizosphere soils,particularly C/N and NH4+-N,had significant effects on the leaf nutrients in trees on the upper ***,rhizosphere soil properties mainly influenced fine root nutrients on the lower slope,and soil AK was the major influencing ***,these

关键词： Tectona grandis Stoichiometric ratio Rhizosphere soil Dominant trees Nutrient accumulation

Growth and mineral nutrient analysis of teak (Tectona grandis) grown on acidic soils in south China

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Journal of Forestry Research 2017年第3期28卷 503-511页

作者： zaizhi zhou Shichao Liu Kunnan Liang Huaming Ma Guihua Huang Research Institute of Tropical Forestry Chinese Academy of Forestry

Teak （Tectona grandis L.f.） is widely planted in the world due to its high market demand, economic, ecological and social value. Its plantations have mostly been established and expanded into sites that are acidic to severely acidic in southern China. But, there are no available and specific evidence-based nutrient management techniques. To better recognize and understand the relationship between teak tree growth and nutrient content in the foliage and soil and establish nutrient norms are critical to optimally manage these young plantations. We studied the foliar nutrient and soil chemistry in 19 representative teak plantations aged 5-8 years. Regression analysis indicated that the mean annual increment of teak volume was linearly and positively correlated with foliar N, Ca, Fe and B concentrations, with soil base saturation percentage, available P and Zn concentrations, and negatively correlated with soil Al concentration. Only if the Ca and Mg contents in soil were enhanced, could the increase in soil base saturation percentage benefit teak growth. A revised classification of low-and high-yielding stands was established by using a sorting method of principal components over 6 foliar macro and 8 micro elements in a Diagnosis and Recommendation Integrated System （DRIS）. Specific DRIS norms for teak plantations in acid soils were derived. The nutrient balance of N, P, K Ca, Mg, Zn, B with Fe or A1, Ca with Mg, and Fe with AI provided a key to promote the growth of teak in acid soils. Meanwhile, soil Zn was also found as a primary trace element that affected teak growth in this study.

关键词： Acid soils DRIS diagnosis and norm Mineral nutrient relationship Plant mineral nutrition Soil properties Teak

Correction to:Effect of slope position on leaf and fi ne root C,N and P stoichiometry and rhizosphere soil properties in Tectona grandis plantations

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林业研究:英文版 2023年第6期34卷 2093-2093页

作者： Zhang, Qingqing zhou, zaizhi Zhao, Weiwei Huang, Guihua Liu, Gaofeng Li, Xiaofei Wu, Junduo Research Institute of Tropical Forestry Chinese Academy of Forestry Guangzhou People’s Republic of China Experimental Center of Tropical Forestry Chinese Academy of Forestry Pingxiang People’s Republic of China

During production process,the below mentioned errors appeared in the original article and inadvertently published with *** corrections are as given below.

关键词： soil rhizosphere correction

外源CO_(2)诱导土沉香树体结香效应及生理响应

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林业科学 2023年第11期59卷 95-102页

作者：刘高峰周再知赵威威张青青黄桂华中国林业科学研究院热带林业研究所广州510520 菏泽学院菏泽274015

【目的】探究土沉香树干填充CO_(2)诱导结香过程与抗逆防御反应,阐明外源CO_(2)诱导下树体结香效应及生理防御机制。【方法】以11年生土沉香为试验材料,采用随机区组设计,设置4个处理,即每隔7天(T1)和15天(T2)充气1次、树干打孔(CK1)和... 详细信息

【目的】探究土沉香树干填充CO_(2)诱导结香过程与抗逆防御反应,阐明外源CO_(2)诱导下树体结香效应及生理防御机制。【方法】以11年生土沉香为试验材料,采用随机区组设计,设置4个处理,即每隔7天(T1)和15天(T2)充气1次、树干打孔(CK1)和不作任何处理(CK2),持续处理3个月。充气开始后第30、60、90、120、150天钻取木芯,测定过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量。处理结束后7和10个月取样观察木质部细胞内含物变化,测定结香范围及醇溶性提取物和沉香四醇含量。【结果】1)土沉香树干填充CO_(2)可加速木质部射线薄壁细胞和导管内淀粉的转化,侵填体随诱导时间增长而增多;T1处理结束后10个月时,射线薄壁细胞和导管被完全堵塞;2)与CK1和CK2相比,CO_(2)处理下木质部变色范围增大,其中T1处理变色范围最大,纵向变色长度26.45 cm、横向变色宽度4.17 cm、径向变色深度9.87 cm;3)随诱导时间增长,T1和T2处理结香区的醇溶性提取物和沉香四醇含量逐渐升高,且均显著高于CK1和CK2;4)T1处理第60天POD、CAT活性达到峰值后缓慢下降,但第150天POD活性仍高于CK2,CAT活性与CK2无显著差异;第90天SOD活性下降,而后缓慢上升;MDA含量先下降后升高,第90天达到最低值,且明显低于CK2;第150天时,SOD活性、MDA含量与CK2无显著差异。【结论】1)外源CO_(2)可显著促进木质部射线薄壁细胞内淀粉的转化,增大导管和射线薄壁细胞内侵填体堵塞面积;2)外源CO_(2)可诱导土沉香木质部变色,随诱导时间增长,树干木质部纵向、横向和径向变色长度增长,纵向变色面积增加;3)外源CO_(2)可诱导土沉香形成沉香块且质地细腻,最优处理10个月时的醇溶性提取物含量达21.27%,沉香四醇含量达0.29%,分别是CK1的1.42和2.11倍;4)外源CO_(2)可在短期内诱导POD、CAT抗氧化酶活性升高,降低MDA含量,激活土沉香树体的抗逆防御反应。

关键词：土沉香 CO_(2) 树干填充结香醇溶性提取物

Parallel Physics-Informed Neural Networks Method with Regularization Strategies for the Forward-Inverse Problems of the Variable Coefficient Modified KdV Equation

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Journal of Systems Science & Complexity 2024年第2期37卷 511-544页

作者： zhou Huijuan School of Science Shanghai Maritime UniversityShanghai 201306China

This paper mainly introduces the parallel physics-informed neural networks(PPINNs)method with regularization strategies to solve the data-driven forward-inverse problems of the variable coefficient modified Korteweg-de Vries(VC-MKdV)*** the forward problem of the VC-MKdV equation,the authors use the traditional PINN method to obtain satisfactory data-driven soliton solutions and provide a detailed analysis of the impact of network width and depth on solving accuracy and ***,the author finds that the traditional PINN method outperforms the one with locally adaptive activation functions in solving the data-driven forward problems of the VC-MKdV *** for the data-driven inverse problem of the VC-MKdV equation,the author introduces a parallel neural networks to separately train the solution function and coefficient function,successfully addressing the function discovery problem of the VC-MKdV *** further enhance the network’s generalization ability and noise robustness,the author incorporates two regularization strategies into the *** amount of numerical experimental data in this paper demonstrates that the PPINNs method can effectively address the function discovery problem of the VC-MKdV equation,and the inclusion of appropriate regularization strategies in the PPINNs can improves its performance.

关键词： Data-driven forward-inverse problems parallel physics-informed neural networks regularization strategies variable coefficient modified KdV equation

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Deep-reinforcement-learning-based UAV autonomous navigation and collision avoidance in unknown environments

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Chinese Journal of Aeronautics 2024年第3期37卷 237-257页

作者： Fei WANG Xiaoping ZHU zhou zhou Yang TANG School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

In some military application scenarios,Unmanned Aerial Vehicles(UAVs)need to perform missions with the assistance of on-board cameras when radar is not available and communication is interrupted,which brings challenges for UAV autonomous navigation and collision *** this paper,an improved deep-reinforcement-learning algorithm,Deep Q-Network with a Faster R-CNN model and a Data Deposit Mechanism(FRDDM-DQN),is proposed.A Faster R-CNN model(FR)is introduced and optimized to obtain the ability to extract obstacle information from images,and a new replay memory Data Deposit Mechanism(DDM)is designed to train an agent with a better *** training,a two-part training approach is used to reduce the time spent on training as well as retraining when the scenario *** order to verify the performance of the proposed method,a series of experiments,including training experiments,test experiments,and typical episodes experiments,is conducted in a 3D simulation *** results show that the agent trained by the proposed FRDDM-DQN has the ability to navigate autonomously and avoid collisions,and performs better compared to the FRDQN,FR-DDQN,FR-Dueling DQN,YOLO-based YDDM-DQN,and original FR outputbased FR-ODQN.

关键词： Faster R-CNN model Replay memory Data Deposit Mechanism(DDM) Two-part training approach Image-based Autonomous Navigation and Collision Avoidance(ANCA) Unmanned Aerial Vehicle(UAV)

Oxidation of emerging organic contaminants by in-situ H_(2)O_(2) fenton system

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Green Energy & Environment 2024年第3期9卷 417-434页

作者： Yuqin Ni Chuxiang zhou Mingyang Xing Yi zhou State Environmental Protection Key Lab of Environmental Risk Assessment and Control on Chemical Processes School of Resources&Environmental EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Advanced Materials and Institute of Fine Chemicals National Engineering Laboratory for Industrial Wastewater TreatmentSchool of Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237China Department of Applied Natural Sciences Technische Hochschule LubeckMonkhofer Weg 23923562 LubeckGermany

The existence and risk of emerging organic contaminants(EOCs)have been under consideration and paid much effort to degrade these *** system is one of the most widely used technologies to solve this *** original Fenton system relies on the hydroxyl radicals produced by Fe(Ⅱ)/H_(2)O_(2) to oxidize the organic ***,the application of the Fenton system is limited by its low iron cycling efficiency and the high risks of hydrogen peroxide transportation and *** introduction of external energy(including light and electricity etc.)can effectively promote the Fe(Ⅲ)/Fe(Ⅱ)cycle and the reduction of oxygen to produce hydrogen peroxide in *** review introduces three in-situ Fenton systems,which are electro-Fenton,Photo-Fenton,and chemical *** mechanism,influencing factors,and catalysts of these three in-situ Fenton systems in degrading EOCs are discussed *** review strengthens the understanding of Fenton and in-situ Fenton systems in degradation,offering further insight into the real application of the in-situ Fenton system in the removal of EOCs.

关键词： In-situ H_(2)O_(2)production Fenton Emerging organic contaminants Photocatalysis Electrocatalysis