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Airborne pollen patterns and their relationship with meteorological factors in the Betula microphylla-dominated wetland of Ebinur Lake,Xinjiang,china

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science china Earth sciences 2021年第10期64卷 1746-1760页

作者： Lixin CHEN Yun ZHANG Zhaochen kong State Key Laboratory of Vegetation and environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China college of Life sciences University of Chinese Academy of SciencesBeijing 100049China college of Earth sciences Hebei GEO UniversityShijiazhuang 050031China

Airborne pollen is indicative of vegetation and climatic *** study investigates airborne pollen trapping in the Betula microphylla-dominated wetland of Ebinur Lake in Northwestern china from September 2012 to August 2015 using Pearson correlation analysis and the Hybrid Single-particle Lagrangian Integrated Trajectory *** temperatures and moderate precipitation during the flowering period facilitated an increase in birch pollen with more exotic spruce pollen carried from the Tianshan Mountains by airflows,leading to the highest arbor pollen concentrations from September 2012 to August *** pollen concentrations from September 2013 to August 2014 were possibly due to an increase in herbaceous pollen resulting from higher temperatures,lower precipitation and more exotic pollen from the desert of southwest Ebinur Lake and Central Asia in summer and *** September 2014 and August 2015,unfavorable climate conditions in summer and autumn decreased the pollen dispersal of xerophytes such as Artemisia and Chenopodiaceae,with little pollen transported from the Kazakh hilly area in late summer,resulting in the lowest pollen *** parameters and air mass movements both greatly affected the atmospheric pollen *** results provide information concerning the dispersion and distribution of birch pollen,paleoenvironmental reconstruction and wetland conservation.

关键词： Airborne pollen Meteorological factor Pearson correlation Betula pollen Ebinur wetland

基于FlowCam影像和YOLOv3深度学习模型的多纹膝沟藻检测

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海洋科学 2024年第2期48卷 15-23页

作者：刘扬孔凡洲于仁成初永宝青岛科技大学环境与安全工程学院山东青岛266042 中国科学院海洋研究所中国科学院海洋生态与环境科学重点实验室山东青岛266071 中国科学院大学北京100049

海洋中的有害藻华,包括微藻形成的赤潮和褐潮以及大型藻类形成的绿潮和金潮,已成为一类突出的海洋生态灾害问题。2021年11—12月,山东半岛东北部海域发生多纹膝沟藻(Gonyaulax polygramma)形成的大规模赤潮,导致海带养殖严重受损,亟待... 详细信息

海洋中的有害藻华,包括微藻形成的赤潮和褐潮以及大型藻类形成的绿潮和金潮,已成为一类突出的海洋生态灾害问题。2021年11—12月,山东半岛东北部海域发生多纹膝沟藻(Gonyaulax polygramma)形成的大规模赤潮,导致海带养殖严重受损,亟待构建有针对性的赤潮监测预警体系。本文以多纹膝沟藻为对象,尝试应用流式影像仪(FlowCam)结合卷积神经网络模型YOLOv3,分别对含有多纹膝沟藻的浓缩海水样品、含有多纹膝沟藻和链状亚历山大藻(Alexandrium catenella)的浓缩海水样品,以及含有多纹膝沟藻活细胞及空壳的浓缩海水样品进行了检测实验,探究了基于藻种影像的深度学习模型在赤潮原因种检测方面的应用潜力。结果表明,在以FlowCam获取的影像数据集训练3万次后,YOLOv3对多纹膝沟藻表现出较好的识别能力,对浓缩海水样品中目标藻种识别的平均精度为88.2%;当样品中存在与多纹膝沟藻形态相似的链状亚历山大藻时,模型对多纹膝沟藻识别的平均精度下降为76.6%,对两种微藻同时进行训练和检测,可将对多纹膝沟藻识别的平均精度提高至84.6%。对于低温下出现脱壳现象的多纹膝沟藻,模型对海水中活细胞识别的平均精度为86.7%,对空壳识别的平均精度87.8%,将多纹膝沟藻活细胞与空壳分别识别的平均精度均值(87.3%)高于将两者统一作为多纹膝沟藻进行检测的识别精度(84.2%),整体识别精度提升3.1%。综合相关结果可以看出,FlowCam与深度学习模型相结合在赤潮监测和研究中具有重要应用潜力。

关键词：深度学习 FlowCam 有害藻华多纹膝沟藻微藻检测

Controls of Land Uses on Soil Retention Curve with Fractal Dimension: Theory and Modeling

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Controls of Land Uses on Soil Retention Curve with Fractal D...

Multi-functional roles of TaSSI2 involved in Fusarium head blight and powdery mildew resistance and drought tolerance

2010 International Conference on Remote Sensing (ICRS 2010)

作者： Yuhe Wu hongjiang Zhang Wei Wang Jinhua Cheng Wenxing Lü college of Soil and Water Conservation beijing Forestry university beijing 100083 china

Use the soil water retention curve model to simulate the soil water retention curve in 3 different forestlands soil in Simian Mountains,and then the fractal dimensions of the curves of soil water retention were calculated with the corresponding experimental *** analyzing the relationship between fractal dimension and the soil texture we found that the fractal dimensions of the curves of soil water retention and soil particle sizes increase gradually with the increase of clay content or decrease of sand ***,the fractal dimensions of the curves of soil water retention are slightly different from that of particle size distribution,and there is a positive correlation between their fractal *** curves of soil water retention are predicted with the fractal model,and results showed that the simulated values of soil water retention curves are similar to the observed values in both coniferous mixed forest and *** of their correlation coefficient were larger than *** reveals that the curves of soil water retention can be predicted with the fractal model in both coniferous mixed forest and tillage in the experimental area,which shows great guiding significance.

关键词： Different land uses’condition soil water retention curve fractal dimension prediction model.

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Journal of Integrative Agriculture 2018年第2期17卷 368-380页

作者： HU Li-qin MU Jing-jing SU Pei-sen WU hong-yan YU Guang-hui WANG Gui-ping WANG Liang MA Xin LI An-fei WANG hong-wei ZHAO Lan-fei kong Ling-rang State Key Laboratory of Crop Biology/Shandong Key Laboratory of Crop Biology/college of Agronomy Shandong Agricultural University Tai'an 271018 P.R.China Agriculture Bureau of Rushan Rushan 264500 P.R. China Shandong Agricultural university Fertilizer science technology Co. Ltd. Feicheng 271600 P.R. China college of Resources and environmental sciences China Agricultural University Beijing 100193 P. R.China

The mutation of the gene encoding a stearoyl-acyl carrier protein fatty acid desaturase（ssi2） has been proved to enhance pathogen resistance in several plants, while it＇s potential to regulate biotic and abiotic stresses in wheat is still unclear. In this study, we cloned TaSSI2 gene in wheat and provided several evidences of its involvement in multiple biological functions. By using barley stripe mosaic virus（BSMV）-induced gene silencing（VIGS） in wheat, it was found that TaSSI2 negatively regulated both powdery mildew and Fusarium head blight（FHB） resistance, which was consistent with the phenotype observed in knock-out mutants of Kronos. The expression of TaSSI2 was down-regulated by in vitro treatments of methyl jasmonate（Me JA）, but positively regulated by salicylic acid（SA） and abscisic acid（ABA）, implying the cross-talk between different hormone signaling pathways involved in wheat to regulate biotic stresses is still to be elucidated. Furthermore, the up-regulated expression of PR4 and PR5 indicated that TaSSI2 probably regulated FHB resistance by depressing the SA signaling pathway in wheat. In addition, the over-expression of TaSSI2 increased the content of linolenic acid（18：3） and subsequently enhanced drought tolerance of transgenic Brachypodium. This phenomenon might be associated with its subcellular localization in the whole cytosol, partly overlapping with Golgi apparatus and the secreted vesicles. As a stearoyl-acyl carrier protein fatty acid desaturase, TaSSI2 was proposed to be involved in cell lipid metabolism and carried targets out of the cell from membrane or wax synthesis, resulting in enhanced drought tolerance in plant.

关键词： TaSSI2 powdery mildew Fusarium head blight drought

天津冬季两个典型污染过程高浓度无机气溶胶成因及来源分析

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环境科学 2024年第5期45卷 2581-2595页

作者：卢苗苗韩素芹刘可欣唐晓孔磊丁净樊文雁王自发天津市环境气象中心天津300074 中国气象局‐南开大学大气环境与健康研究联合实验室天津300074 南开大学环境科学与工程学院天津市城市交通污染防治研究重点实验室天津300071 中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029 中国科学院大气物理研究所国际气候与环境科学中心北京100029 中国科学院大学地球与行星科学学院北京100049

无机气溶胶是天津冬季霾天出现的主要成分,研究挑选了2020年1月污染天中两个典型的高浓度无机气溶胶(SIA)过程(CASE1和CASE2),利用观测数据和耦合了在线污染物来源追踪方法的大气化学传输模式NAQPMS综合探究了气象要素、区域输送和化学... 详细信息

无机气溶胶是天津冬季霾天出现的主要成分,研究挑选了2020年1月污染天中两个典型的高浓度无机气溶胶(SIA)过程(CASE1和CASE2),利用观测数据和耦合了在线污染物来源追踪方法的大气化学传输模式NAQPMS综合探究了气象要素、区域输送和化学过程的影响.两个过程的ρ(SIA)均值分别为76.8μg·m^(−3)和66.0μg·m^(−3),硝酸盐浓度高于硫酸盐和铵盐,均为硝酸盐为主导的污染过程.气象条件影响了无机气溶胶的生成,CASE1过程ρ(SIA)>80μg·m^(−3)对应的温度和相对湿度区间分别是[−6℃,0℃]、[2℃,4℃]和[50%,60%]、[80%,100%];CASE2过程对应的温度和相对湿度区间分别是[2℃,4℃]和[60%,70%].外来源对CASE1和CASE2过程SIA的平均贡献率为62.3%和22.1%,分别为区域传输主导和局地生成主导过程.CASE1本地排放对硝酸盐和硫酸盐的贡献分别为16.2μg·m^(−3)和8.2μg·m^(−3),均高于外来源的贡献(31.7μg·m^(−3)和8.8μg·m^(−3));CASE2过程本地排放对硝酸盐和硫酸盐的贡献分别为29.3μg·m^(−3)和25.1μg·m^(−3),而外来源的贡献为8.1μg·m^(−3)和9.4μg·m^(−3).这表明CASE1本地生成和外来源输送贡献造成硝酸盐高于硫酸盐浓度,而CASE2仅本地源造成硝酸盐浓度高于硫酸盐.两个污染过程气相氧化反应是无机气溶胶生成的首要来源,贡献率分别为48.9%和57.8%;非均相反应也是重要过程,对SIA的贡献率分别为48.1%和42.2%;液相反应的影响小.

关键词：无机气溶胶气象因素区域传输化学过程天津

Incremental Study Based on Support Vector Used to Anomaly Detection for Hyperspectral Imagery

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Incremental Study Based on Support Vector Used to Anomaly De...

2010 International Conference on Remote Sensing (ICRS 2010)

作者： Liyan Zhang1 Derong Chen2 Yonghua Sun1 1.Key Laboratory of 3D Information Acquisition and Application of the Ministry of Education Key Laboratory of Integrated Disaster Assessment and Risk Governance of the Ministry of Civil Affairs Key Laboratory of Resource environment and GIS of beijing. Capital Normal university 2. college of Mechanical and Electrical engineering beijing Institute of technology beijing Peoples R china

While detecting anomalies in hyperspectral imagery with support vector data description （SVDD）, large numbers of operation was run because of the high dimension character of dataset and the complexity of background and the high miss rate was discovered because of the interfered background by interior anomalies. This paper used incremental support vector data description （ISVDD） method that samples are divided many sub- sample, and incremental study is designed to simplify the computation. On every sub-sample study, optimization is needed according of the support vectors obtained from above sub-sample and current sub-sample data. By the experiment on the HYMAP data, computation complexity of the algorithm decrease obviously and the computation speed increase highly under the similar detection effect compared with SVDD algorithm.

关键词： hyperspectral imagery anomaly detection incremental support vector data description

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大食物观统筹下的耕地保护协同治理体系研究

西南大学学报（自然科学版） 2024年第10期46卷 46-58页

作者：浦男萍赵晶张颖张蚌蚌雷鸣孔祥斌中国农业大学土地科学与技术学院北京100193 北京方圆大地规划设计咨询有限公司北京100095 北京市农村经济研究中心史志处北京100192 西北农林科技大学经济管理学院陕西杨凌712100 中国社会科学院生态文明研究所北京100710

随着我国经济社会的快速发展和食物需求结构的转变,耕地保护制度在维护国家粮食安全和促进区域协调发展中的作用愈发凸显.从大食物观的提出及其与耕地保护的关系出发,分析了当前耕地保护面临的诸多挑战,如食物需求结构转型、区域分工协... 详细信息

随着我国经济社会的快速发展和食物需求结构的转变,耕地保护制度在维护国家粮食安全和促进区域协调发展中的作用愈发凸显.从大食物观的提出及其与耕地保护的关系出发,分析了当前耕地保护面临的诸多挑战,如食物需求结构转型、区域分工协同需求以及耕地后备资源的稀缺性.在总结我国耕地保护成效与不足的基础上,深入探讨了耕地安全的基本事实,粮食安全现状与耕地保护目标之间的差距,以及耕地保护效能降低的原因,并识别了耕地保护面临的机遇与挑战.针对这些问题,提出了一系列创新路径,包括加强土地资源调查、优化占补平衡政策、建立区域补偿机制和第三方评估体系等,以期为构建大食物观统筹下的耕地保护协同治理体系提供政策参考.

关键词：大食物观粮食安全耕地治理实现路径

Mechanisms for flowering plants to benefit arthropod natural enemies of insect pests： Prospects for enhanced use in agriculture

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Insect science 2014年第1期21卷 1-12页

作者： Zhong-Xian Lu Ping-Yang Zhu Geoff M. Gurr Xu-Song Zheng Donna M. Y. Read kong-Luen Heong Ya-Jun Yang hong-Xing Xu State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control Institute of Plant Protection and Microbiology Zhejiang Academy of Agricultural Sciences Hangzhou China EH Graham Centre for Agricultural Innovation Charles Stuff University Orange NSW Australia college of Chemistry and Life science Zhejiang Normal University Jinhua Zhejiang Province China and Crop and environmental sciences division International Rice Research Institute Los Banos Metro Manila Philippines

Reduction of noncrop habitats, intensive use of pesticides and high levels of disturbance associated with intensive crop production simplify the farming landscape and bring about a sharp decline of biodiversity. This, in turn, weakens the biological control ecosystem service provided by arthropod natural enemies. Strategic use of flowering plants to enhance plant biodiversity in a well-targeted manner can provide natural enemies with food sources and shelter to improve biological control and reduce dependence on chemical pesticides. This article reviews the nutritional value of various types of plant-derived food for natural enemies, possible adverse effects on pest management, and the practical application of flowering plants in orchards, vegetables and field crops, agricultural systems where most research has taken place. Prospects for more effective use of flowering plants to maximize biological control of insect pests in agroecosystem are good but depend up on selection of optimal plant species based on information on the ecological mechanisms by which natural enemies are selectively favored over pest species.

关键词： conservation biological control ecological engineering habitat nectar,nutrition pollen shelter

First Biological Records of Palaeoecology Changes Inferred from Pollen since 4800 cal. a B.P. in Alahake Saline Lake of North Xinjiang

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1249-1250页

作者： LI Yumei ZHANG Yun ZHAO Long kong Zhaochen college of Earth sciences Jilin University Changchun 130061 Jilin China State Key Laboratory of Vegetation and environmental Change Institute of Botany Chinese Academy ofSciences Beijing 100093 China beijing Institute of Geo-environment Monitoring Beijing 100195 China

Objective As the resource treasury of desert biodiversity,the wetland of Betula halophila has fragile ecologic system and low stability,which causes the sudden reduction of wetland *** Alahake Saline Lake is known for an endangered species,Betula ***,palaeoecology changes of the Alahake Saline Lake have been little ***,it is necessary to

关键词： First Biological Records Alahake Saline Lake