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大数据时代背景下“地球化学多元统计分析”课程混合式教学改革与实践

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中国地质教育 2024年第1期33卷 76-80页

作者：夏学齐龚庆杰刘宁强中国地质大学(北京)地球科学与资源学院北京100083

“地球化学多元统计分析”是面向地球化学专业本科四年级开设的专业核心课程。在大数据时代背景下,原有的课程教学模式面临内容相对陈旧、课时严重不足、实践操作教学效果不理想等问题。笔者尝试开展了线上线下混合式课程教学改革并实践... 详细信息

“地球化学多元统计分析”是面向地球化学专业本科四年级开设的专业核心课程。在大数据时代背景下,原有的课程教学模式面临内容相对陈旧、课时严重不足、实践操作教学效果不理想等问题。笔者尝试开展了线上线下混合式课程教学改革并实践,包括更新教学内容体系和教材、整合网上教材和教学资源、扩充相关软件的操作训练、理论授课与实验课交叉进行、课堂授课与课后作业有机融合等,同时融入了教学思政内容,教学效果明显提高。

关键词：混合式教学地球化学在线多媒体教材大数据

Spatial analysis of land use change effect on soil organic carbon stocks in the eastern regions of China between 1980 and 2000

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Geoscience Frontiers 2017年第3期8卷 597-604页

作者： xueqi xia Zhongfang Yang Yuan Xue Xin Shao Tao Yu Qingye Hou School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China Chongqing Institute of Land Surveying and Planning Chongqing 404000 China

Spatial distributions of 0-20 cm soil carbon sources/sinks caused by land use changes from the year 1980 to 2000 in an area of 2.97 ~ 106 km2 in eastern China were investigated using a land use dataset from a recent soil geochemical survey. A map of soil carbon sourcesJsinks has been prepared based on a spatial analysis scheme with GIg. Spatial statistics showed that land use changes had caused 30.7 ＋ 13.64 Tg of surface soil organic carbon loss, which accounts for 0.33% of the total carbon storage of 9.22 Pg. The net effect of the carbon source was estimated to be ~ 71.49 Tg soil carbon decrease and ~ 40.80 Tg increase. Land use changes in Northeast China （NE） have the largest impact on soil organic carbon storage compared with other regions. Paddy fields, which were mainly transformed into dry farmland in NE, and constructed land in other regions, were the largest carbon sources among the land use types. Swamp land in NE was also another large soil carbon source when it was transformed into dry farmland or paddy fields. Dry farmland in the NE region formed the largest soil organic carbon sink, as some were trans- formed into paddy fields, forested land, and other land use types with high SOCD.

关键词： Land use change Soil organic carbon GIS Eastern China

干旱区土壤无机碳碳汇作用及其对固碳减排贡献研究进展

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中国地质 2024年第4期51卷 1210-1242页

作者：李畅杨忠芳余涛牛荣琛郭茹璨余保成夏学齐于朝阳曹圆圆中国地质大学(北京)地球科学与资源学院北京100083 自然资源部生态地球化学重点实验室北京100037 中国地质大学(北京)数理学院北京100083 中国矿业大学(北京)地球科学与测绘工程学院北京100083 宁夏回族自治区地球物理地球化学调查院宁夏银川750000

【研究目的】干旱区土壤无机碳作为全球碳循环举足轻重的组成部分,其碳汇效应不容忽视。【研究方法】本文查阅了大量国内外干旱区土壤无机碳的相关文献,重点对土壤无机碳汇确认、碳库组成、来源识别,以及碳汇影响因素进行了系统性归纳... 详细信息

【研究目的】干旱区土壤无机碳作为全球碳循环举足轻重的组成部分,其碳汇效应不容忽视。【研究方法】本文查阅了大量国内外干旱区土壤无机碳的相关文献,重点对土壤无机碳汇确认、碳库组成、来源识别,以及碳汇影响因素进行了系统性归纳总结。【研究结果】干旱区无机碳汇效应伴随着干旱区负通量研究得到确认,但其碳库组成十分复杂,包括了液相碳库与固相碳库。其中液相储库主要以可溶性碳酸盐形式赋存于干旱区地下水体;固相储库则为以固相碳酸盐矿物的形式赋存在土壤中,依据不同成因来源分为成岩碳酸盐与成土碳酸盐,后者又细分为碳质成土碳酸盐与硅质成土碳酸盐。成土碳酸盐中的硅质成土碳酸盐具备真正长期稳定的碳汇效应。无机碳汇的影响因素复杂,包括了自然的气候、土壤性质与深度、生物作用、成土母质、土壤有机质等因素,以及土地利用与土地覆盖、农业管理措施等人为因素。【结论】干旱区土壤无机碳对全球碳循环研究极其重要,当前研究主要聚焦在土壤无机碳来源分辨,碳汇效应强度确认与固碳潜力量化,以及影响因素明确与人为干预的可能性评估等方面。在实现“双碳目标”驱动下,查清干旱—半干旱地区土壤无机碳源汇过程与影响因素必将是未来的研究热点,也是解决“碳失汇”科学难题的突破点,极大地推动全球碳循环研究。

关键词：土壤无机碳干旱—半干旱地区碳汇碳库组成来源识别影响因素环境地质调查工程

Temporal variation of soil carbon stock and its controlling factors over the last two decades on the southern Song-nen Plain,Heilongjiang Province

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Geoscience Frontiers 2010年第1期1卷 125-132页

作者： xueqi xia Zhongfang Yang Yan Liao Yujun Cui Yansheng Li School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China Heilongjiang Institute of Geological Survey Harbin 150036 China

Against the current background of global climate change, the study of variations in the soil carbon pool and its controlling factors may aid in the evaluation of soil＇s role in the mitigation or enhancement of greenhouse gas. This paper studies spatial and temporal variation in the soil carbon pool and their controlling factors in the southern Song-nen Plain in Heilongjiang Province, using soil data collected over two distinct periods by the Multi-purpose Regional Geochemical Survey in 2005-2007, and another soil survey conducted in 1982-1990. The study area is a carbon source of 1479 t/km2 and in the past 20 years, from the 1980s until 2005, the practical carbon emission from the soil was 0.12 Gt. Temperature, which has been found to be linearly correlated to soil organic carbon, is the domi- nant climatologic factor controlling soil organic carbon contents. Our study shows that in the relevant area and time period the potential loss of soil organic carbon caused by rising temperatures was 0.10 Gt, the potential soil carbon emission resulting from land-use change was 0.09 Gt, and the combined potential loss of soil carbon （0.19 Gt） caused by warming and land-use change is comparable to that of fossil fuel combustion （0.21 Gt）. Due to the time delay in soil carbon pool variation, there is still 0.07 Gt in the potential emission caused by warming and land-use change that will be gradually released in the future.

关键词： The southern Song-nen Plain in Heilongjiang Province Soil carbon pool Spatial and temporal variation Carbon cycle

Transcriptomic Analysis Reveals the Formation Mechanism of Anthocyanins Light-Independent Synthesis in Chrysanthemum

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1599-1621页

作者： Fangye Liu Jiaping Qu Yajun Li Jiawei Fan Yumeng Cui Jingwen Wu xueqi Gu xia Li He Huang Beijing Advanced Innovation Center for Tree Breeding by Molecular Design Beijing Key Laboratory of Ornamental Plants Germplasm Innovation&Molecular BreedingNational Engineering Research Center for FloricultureBeijing Laboratory of Urban and Rural Ecological EnvironmentKey Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Education MinistrySchool of Landscape ArchitectureBeijing Forestry UniversityBeijing100083China Urban Construction School Beijing City UniversityBeijing100083China

Chrysanthemum×morifolium is a horticultural crop which plays a vital role in theﬂower industry with signiﬁ-cant economic value and has a cultivation history of over three thousand years in *** accumulation of anthocyanins is always affected by ***,we revealed that anthocyanin accumulation is highly dependent on light in‘2021135’genotype chrysanthemum,while it is light-independent in‘2001402’genotype ***,no literature has been reported regarding the non-photosensitive chrysanthemum in anthocya-nins light-independent synthesis *** the phenotype analysis of 44 F1 generations,we found that light-independence is a dominant trait which can be stable inherited by *** transcriptome of the rayﬂorets of‘2021135’and‘2001402’under light and bagging treatment were sequenced and *** on weighted gene co-expression network analysis(WGCNA),K-means analysis,and Real-Time Quantitative Poly-merase Chain Reaction(RT-qPCR)analysis,16 genes were highly correlated with the anthocyanin *** anthocyanin content of rayﬂorets treated with different light-quality conditions indicated that blue light signiﬁ-cantly affected anthocyanin *** Yeast one-hybrid analysis,CmBIC1.1 and CmBIC1.2 can directly regulate the anthocyanin structural gene *** our study,we revealed the important characteristics of light-independent anthocyanin synthesis in chrysanthemums and screened regulatory factors in light-depen-dent and light-independent anthocyanin synthesis *** results laid the groundwork for subsequent ana-lysis of the molecular mechanism involved in the light-independent synthesis of anthocyanins in chrysanthemums.

关键词： Chrysanthemum non-photosensitive transcriptome anthocyanin biosynthesis

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青藏高原卫星紫外后向散射辐射的正演仿真

光学精密工程 2022年第3期30卷 256-263页

作者：孙诗雅黄富祥夏学齐中国地质大学(北京)地球科学与资源学院北京100083 中国气象局国家卫星气象中心北京100081 中国气象局中国遥感卫星辐射测量和定标重点开放实验室北京100081

为了定量评估像元下垫面反射率等要素对青藏高原卫星臭氧遥感数据精度的影响,设计了青藏高原卫星太阳紫外后向散射辐射的正演仿真计算。首先提取NOAA卫星SBUV/2青藏高原像元下垫面的观测数据,结合提取的臭氧垂直廓线数据,设计青藏高原... 详细信息

为了定量评估像元下垫面反射率等要素对青藏高原卫星臭氧遥感数据精度的影响,设计了青藏高原卫星太阳紫外后向散射辐射的正演仿真计算。首先提取NOAA卫星SBUV/2青藏高原像元下垫面的观测数据,结合提取的臭氧垂直廓线数据,设计青藏高原正演仿真计算的输入参数,最后输入风云三号卫星紫外臭氧垂直探测仪正演仿真计算系统开展正演仿真计算,利用计算结果,考察卫星紫外臭氧垂直探测仪通道辐射观测值随下垫面特征参数的变化特征。结果表明:当太阳天顶角在30°~88°内变化时,仪器各个通道的辐亮度观测值都随太阳天顶角增大而减小,变率在-0.002%~-46.24%,变率随着波长的增大而增大,其中第12通道的最大达到-46.24%;当像元下垫面反射率在0~0.8内变化时,仪器通道辐亮度观测值的变化特征随波长不同而有显著差异,其中短波长的第1~6通道,对观测值的影响几乎可以忽略不计,而长波长的第7~12通道,观测值随着下垫面反射率的增大而增大,而且这种变率随着波长的增大而快速增加,第12通道的最大变率达到2903.2%;像元下垫面有效气压的改变,对仪器通道辐亮度观测值的影响可以忽略不计。

关键词：卫星遥感青藏高原紫外臭氧垂直探测仪正演计算辐射传输

2011-2020中国应用地球化学研究进展与展望之生态地球化学

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现代地质 2020年第5期34卷 883-896页

作者：夏学齐龚庆杰徐常艳中国地质大学(北京)地球科学与资源学院北京100083

生态地球化学在调查的基础上,以元素在不同生态系统中的循环为主线开展生态地球化学评价,通过输入输出通量调查和重访监测掌握元素循环的发展规律,从而对元素、化合物和其他地球化学参数的发展趋势进行预测预警,并提出开发或修复建议。... 详细信息

生态地球化学在调查的基础上,以元素在不同生态系统中的循环为主线开展生态地球化学评价,通过输入输出通量调查和重访监测掌握元素循环的发展规律,从而对元素、化合物和其他地球化学参数的发展趋势进行预测预警,并提出开发或修复建议。近十年,该学科在实践应用的基础上进行理论框架和技术方法的不断拓展,不仅产生了大量技术标准、论文和专著等书面成果,还在污染控制、土地资源合理利用、特色农产品开发、土壤碳汇和抑制气候变化等方面产生了积极作用。在理论研究和应用实践需求的推动下在土壤碳库与全球变化、土壤重金属高背景产生机制、土地质量地球化学评价、土壤有益元素开发和土壤污染修复等方面不断产生分支研究方向。主要回顾和总结2011年以来,我国生态地球化学学科研究进展。

关键词：生态地球化学调查生态地球化学评价土地质量地球化学评价生态风险预测预警

土地生态质量遥感评价模型与主控因子研究——以广安市为例

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国土资源遥感 2021年第1期33卷 191-198页

作者：陈震夏学齐陈建平中国地质大学(北京)地球科学与资源学院北京100083

为了科学评价土地生态质量以及有效识别土地生态主控因子,开展土地生态质量遥感评价模型与主控因子研究,以四川省广安市为研究区,建立基于理想点的遥感评价模型,对广安市2000年、2005年、2010年和2015年的土地生态质量进行评价及主控因... 详细信息

为了科学评价土地生态质量以及有效识别土地生态主控因子,开展土地生态质量遥感评价模型与主控因子研究,以四川省广安市为研究区,建立基于理想点的遥感评价模型,对广安市2000年、2005年、2010年和2015年的土地生态质量进行评价及主控因子分析;以公里网格为评价单元,以生态本底、生态结构、生态效益及生态胁迫4个准则层的14个评价指标构建评价指标体系;应用德尔菲法和熵权法(即主观结合客观的方法)计算各评价指标权重值,以理想点模型计算理想点值、划分理想点生态等级,利用主成分分析法获取各年份的主控因子,然后对理想点生态等级空间分布与环境影响因子之间的关系进行分析。结果表明:2005—2015年第3等级面积占比有一定幅度上升,第3等级面积占比为各等级最大,因而广安市土地生态质量整体上呈上升趋势、林地面积占比和气温因子是最重要的主控因子、气温与土地生态质量正相关等研究结果。研究结果可为土地整治部门提出广安市土地生态质量监管的决策依据和技术支持,也可对其他地区的土地生态质量监管工作提供借鉴。

关键词：土地生态质量生态评价指标理想点模型主控因子主成分分析

Analytical Solutions for an Isotropic Elastic Half-Plane with Complete Surface Effects Subjected to a Concentrated/Uniform Surface Load

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Acta Mechanica Solida Sinica 2024年第3期37卷 371-384页

作者： xia-Hui Pan School of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China

Within the context of Gurtin-Murdoch surface elasticity theory,closed-form analytical solutions are derived for an isotropic elastic half-plane subjected to a concentrated/uniform surface *** the effects of residual surface stress and surface elasticity are *** stress function method and Fourier integral transform technique are *** solutions are provided in a compact manner that can easily reduce to special situations that take into account either one surface effect or none at *** results indicate that surface effects generally lower the stress levels and smooth the deformation profiles in the *** elasticity plays a dominant role in the in-plane elastic fields for a tangentially loaded half-plane,while the effect of residual surface stress is fundamentally crucial for the out-of-plane stress and displacement when the half-plane is normally *** the remaining situations,combined effects of surface elasticity and residual surface stress should be *** results for a concentrated surface force serve essentially as fundamental solutions of the Flamant and the half-plane Cerruti problems with surface *** solutions presented in this work may be helpful for understanding the contact behaviors between solids at the nanoscale.

关键词： Surface effects Residual surface stress Surface elasticity Half-plane Analytical solutions