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Gully Erosion Regionalization of Black Soil Area in Northeastern China

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Chinese Geographical Science 2017年第1期27卷 78-87页

作者： yanG jiuchun ZHANG Shuwen CHANG Liping LI Fei LI Tianqi GAO yan Northeast Institute of Geography and Agroecology Chinese Academy of Sciences College of Earth Science Jilin University College of Environment and Planning Henan University Songliao River Basin Water Conservancy Committee Ministry of Water Resources

Gully erosion is the frequent and main form of soil erosion in the black soil area of the northeastern China, which is one of the most important commodity grain production bases in China. It is encroaching upon the fertile farmland there. Regionalization of gully erosion can reveal the spatial distribution and regularity of the development of gully erosion. Based on the eco-geographical regional background features of the black soil area, this study combined the regionalization with influencing factors of the development of gully erosion. GIS spatial analysis, geostatistical analysis, spatial statistics, reclassification, debris polygon processing and map algebra methods were employed. As a result, the black soil area was divided into 12 subregions. The field survey data on type, length, volume and other characteristics indicators of gully erosion were used to calibrate the results. Then the features of every subregion, such as where the gully erosion is, how serious it is, and why it happens and develops, were expounded. The result is not only an essential prerequisite for gully erosion surveys and monitoring, but also an important basis for gully erosion prevention.

关键词： regionalization gully erosion soil and water conservation black soil area northeastern China

Remote Sensing Monitoring of Gullies on a Regional Scale: A Case Study of Kebai Region in Heilongjiang Province, China

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Chinese Geographical Science 2015年第5期25卷 602-611页

作者： ZHANG Shuwen LI Fei LI Tianqi yanG jiuchun BU Kun CHANG Liping WANG Wenjuan yan Yechao Northeast Institute of Geography and Agroecology Chinese Academy of Sciences College of Earth Science Jilin University Henan University

Gully erosion is one of the major causes of land degradation in most areas and attracts increasing attention from researchers. We monitored gullies in the Kebai region in Heilongjiang Province of China by using remote sensing data and found that gully density increased with the increase in slope when the slope was less than 3°. Gully density in sunny slopes or windward slopes was greater than in shady slopes or leeward slopes because of the impacts of freezing and thawing, wind and solar radiation. Specifically, the gully density in northeast slope was the greatest and in southwest was the smallest. Gully density was reduced with increasing slope length and the longer the slope length, the less the gully density changed between 1965 and 2005. Affected by runoff, gullies most easily to occur in concave slopes and the critical elevation for gully erosion was 250–275 m. Moreover, hilly regions had the greatest gully density, followed by tableland regions, whereas the gully density in flatlands was the lowest. However, the gully density of these three types of landforms all increased between 1945 and 2000, and the portion of increase was 57.45%(hill), 52.91%(mesa) and 25.32%(plain), respectively.

关键词： gully density gully erosion monitoring remote sensing Kebai region, China

China's Wetland Databases Based on Remote Sensing Technology

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Chinese Geographical Science 2017年第3期27卷 374-388页

作者： yan Fengqin LIU Xingtu CHEN Jing YU Lingxue yanG Chaobin CHANG Liping yanG jiuchun ZHANG Shuwen Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China International Center for Climate and Global Change Research and School of Forestry and Wildlife Sciences Auburn UniversityAuburn 36849USA College of Earth Science Jilin UniversityChangchun 130061China College of Arts&Sciences Beijing Union UniversityBeijing 100083China

Wetland databases can provide the basic data that necessary for the protection and management of wetlands. A large number of wetland databases have been established in the world as well as in China. In this paper, we review China's wetland databases based on remote sensing(RS) technology after introducing the background theory to the application of RS technology in wetland surveys. A key conclusion is that China's wetland databases are far from sufficient in fulfilling protection and management needs. Our recommendations focus on the use of the hyper-spectral imagery, microwave data, multi-temporal images, and automatic classifications in order to improve the accuracy and efficiency of wetland inventory. Further, attention should also be paid to detect major biophysical features of wetlands and build wetland databases in years after the 1980 s in China. Considering that great gap exists between RS experts and wetland experts, further cooperation between wetland scientists and RS scientists are needed to promote the application of RS in the foundation of wetland databases.

关键词： wetlands inventory remote sensing mapping China

Cropland redistribution to marginal lands undermines environmental sustainability

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National Science Review 2022年第1期9卷 66-78页

作者： Wenhui Kuang Jiyuan Liu Hanqin Tian Hao Shi Jinwei Dong Changqing Song Xiaoyong Li Guoming Du Yali Hou Dengsheng Lu Wenfeng Chi Tao Pan Shuwen Zhang Rafiq Hamdi Zherui Yin Huimin yan Changzhen yan Shixin Wu Rendong Li jiuchun yang Yinyin Dou Wenbin Wu Liqiao Liang Bao Xiang Shiqi yang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences International Center for Climate and Global Change Research School of Forestry and Wildlife Sciences Auburn University Faculty of Geographical Science Beijing Normal University State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Public Administration and Law Northeast Agricultural University School of Geographical Sciences Fujian Normal University School of Resources and Environmental Economics Inner Mongolia University of Finance and Economics School of Geography and Tourism Qufu Normal University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Royal Meteorological Institute of Belgium Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Key Laboratory for Resources Use & Environmental Remediation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Hubei Province’s Key Laboratory for Environment & Disaster Monitoring and Evaluation Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Institute of Ecology Chinese Research Academy of Environmental Sciences College of Environment and Planning Henan University

Cropland redistribution to marginal land has been reported worldwide;however,the resulting impacts on environmental sustainability have not been investigated *** we investigated the environmental impacts of cropland redistribution in *** a result of urbanization-induced loss of high-quality croplands in south China(～8.5 t ha),croplands expanded to marginal lands in northeast(～4.5 t ha) and northwest China(～2.9 t ha) during 1990-2015 to pursue food ***,the reclamation in these low-yield and ecologically vulnerable zones considerably undermined local environmental sustainability,for example increasing wind erosion(+3.47%),irrigation water consumption(+34.42%),fertilizer use(+20.02%) and decreasing natural habitats(-3.11%).Forecasts show that further reclamation in marginal lands per current policies would exacerbate environmental costs by *** future cropland security risk will be remarkably intensified because of the conflict between food production and environmental *** research suggests that globally emerging reclamation of marginal lands should be restricted and crop yield boost should be encouraged for both food security and environmental benefits.

关键词： cropland redistribution environmental sustainability marginal lands wind erosion irrigation water consumption

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电动汽车移动储能辅助频率控制策略的研究

电工技术学报 2015年第11期30卷 115-126页

作者：鲍谚贾利民姜久春张维戈北京交通大学国家能源主动配电网技术研发中心北京100044 北京交通大学交通运输学院北京100044

大量电动汽车接入电网后,不仅可以作为可控充电负荷存在,也可以作为移动储能装置为电网提供服务与支持。首先分析了电动汽车参与电网频率控制的优势,介绍了一种移动储能辅助调频系统的结构框架及工作机理。基于电力系统频率调节控制基... 详细信息

大量电动汽车接入电网后,不仅可以作为可控充电负荷存在,也可以作为移动储能装置为电网提供服务与支持。首先分析了电动汽车参与电网频率控制的优势,介绍了一种移动储能辅助调频系统的结构框架及工作机理。基于电力系统频率调节控制基本动态模型,建立了电动汽车参与电网一次、二次频率调节控制的模型。在此基础上,针对相关研究较少考虑电动汽车车辆属性的特点,提出了计及车辆限制和用户需求的电动汽车参与电网频率调节的控制策略。该策略能够满足车辆用户用车时间和容量的个性化需求,同时有效避免了荷电状态超限和充放电电流倍率过大对电池造成的不利影响。最后,通过两个算例对提出的模型和控制策略进行了研究分析,验证了模型与策略的可靠性。

关键词：电动汽车辅助调频车辆限制用户需求控制策略

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锰酸锂动力电池寿命测试方法

汽车工程 2015年第1期37卷 67-71,119页

作者：时玮张言茹陈大分姜久春姜君梁彦北京交通大学国家能源主动配电网技术研发中心北京100044 北京交通大学电气工程学院北京100044

以北京奥运会用锰酸锂电池为对象,通过电池的实际运行环境和电池容量衰退多种影响因素的分析,从充放电倍率应力、温度应力和放电深度应力3方面进行与实际运行环境等效的应力条件下的电池寿命测试。利用拟合的衰退数据得到了锂离子动力... 详细信息

以北京奥运会用锰酸锂电池为对象,通过电池的实际运行环境和电池容量衰退多种影响因素的分析,从充放电倍率应力、温度应力和放电深度应力3方面进行与实际运行环境等效的应力条件下的电池寿命测试。利用拟合的衰退数据得到了锂离子动力电池的寿命模型参数,利用线性累积法简化了电池容量衰退模型,提出了一种面向不同实际应用场合的电池寿命测试方法。与模拟混合四季温度的电池寿命数据对比验证了该简化模型的有效性,它有效缩短了电池寿命测试周期。

关键词：锰酸锂电池等效测试应力寿命模型寿命测试

基于ERA5-LAND的中国东北地区近地表土壤冻融状态时空变化特征

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地理学报 2021年第11期76卷 2765-2779页

作者：岳书平闫业超张树文杨久春王文娟南京信息工程大学地理科学学院南京210044 中国科学院东北地理与农业生态研究所长春130102 河南财经政法大学资源与环境学院郑州450046

土壤冻融交替是陆地表层极其重要的物理过程,土壤冻融状态的频繁变化对地气能量交换、地表径流、植被生长、生态系统及土壤碳氮循环等均具有重要的影响。本文基于1981—2019年ERA5-LAND逐小时土壤温度数据,借助GIS空间分析功能,利用Pyt... 详细信息

土壤冻融交替是陆地表层极其重要的物理过程,土壤冻融状态的频繁变化对地气能量交换、地表径流、植被生长、生态系统及土壤碳氮循环等均具有重要的影响。本文基于1981—2019年ERA5-LAND逐小时土壤温度数据,借助GIS空间分析功能,利用Python编程处理分析了中国东北地区近地表土壤冻融状态的时空变化特征。结果表明:从不同冻融状态起始日期的空间分布来看,近地表不同阶段的起始日期主要受纬度和地形的影响,具有明显的纬度地带性和垂直地带性。春季冻融过渡期和完全融化期的起始日期由东南向西北均呈逐渐推迟趋势,而秋季冻融过渡期与完全冻结期起始日期则由东南向西北随纬度升高越来越早。就不同冻融状态发生天数的空间分布而言,研究区南部春季冻融过渡期发生天数多于北部,西部多于东部,年均发生天数均在30 d以内;秋季发生冻融的天数空间差异不大,研究区一半以上的地区年均发生天数在10 d以内。完全融化期发生天数最多,从东南向西北呈逐渐减少趋势,年均发生天数主要介于150~240 d之间;完全冻结期发生天数则由南向北日益增多,其空间分布表现为一向南开口的簸箕形,各地年均发生天数集中于90~180 d之间。从时间变化趋势来看,近年来春季冻融过渡期起始日期以提前趋势为主,而秋季冻融过渡期起始日期总体表现为延后,致使完全融化期发生天数以增加趋势为主,年均变化速度高达0.2 d/a;大兴安岭以西、呼伦贝尔高原以北地区及辽河平原春季冻融过渡期发生天数呈减少趋势,其他地区为增加趋势;大兴安岭以西地区、呼伦贝尔高原以北地区完全融化期起始日期明显提前;松嫩平原和长白山区秋季冻融过渡期起始日期推迟显著,发生天数的变化趋势呈北增南减的空间分异特征;不同地区完全冻结期起始日期的变化趋势差异显著,中部广大的平原区呈不显著的推迟趋势,而大、小兴安岭、长白山、辽东半岛和辽西丘陵则提前进入完全冻结状态;研究区完全冻结期发生天数呈减少趋势,研究区中部的季节冻土区完全冻结期明显变短,年均减少速度大于0.2 d/a。

关键词： ERA5-LAND 土壤冻融状态冻土时空变化东北地区

基于地名志的东北历史时期土地利用变化研究——以吉林省镇赉县为例

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地球信息科学学报 2010年第2期12卷 174-179页

作者：吕妍张树文杨久春吉林大学地球科学学院长春130061 中国科学院东北地理与农业生态研究所长春130012 中国科学院研究生院北京100049

研究历史时期的土地利用与土地覆被变化,对于人类的生产活动有着重要的借鉴意义。本文以吉林省镇赉县为例,探讨了地名志等历史资料在确定东北地区大规模开发利用初始年限研究中的应用,并结合重分类、重心转移分析、叠加分析方法,分析了... 详细信息

研究历史时期的土地利用与土地覆被变化,对于人类的生产活动有着重要的借鉴意义。本文以吉林省镇赉县为例,探讨了地名志等历史资料在确定东北地区大规模开发利用初始年限研究中的应用,并结合重分类、重心转移分析、叠加分析方法,分析了镇赉县地名志等史料记载的土地开发利用特征。结果表明:在康熙年间和1853年,镇赉县先后有过有记载的定居后小范围开垦活动,而直到1875年开始持续的土地开垦利用,此前镇赉县基本上处于自然状态。在技术手段不发达的早期,村屯的演变过程与土地开发利用过程是相辅相成的,因此,从村屯演变特征来看,1907-1912年期间土地开发利用最为突出;到1975年时,镇赉县村屯格局基本形成,而此时的土地开发利用活动已由个人行为转变为集体的机械化。在开禁等政策、自然灾害,以及战争等影响下,镇赉县土地开发呈由东部和中部的平坦地区向西部地势较高地区扩展的过程。

关键词：地名志历史时期村屯演变土地开发镇赉县

电动汽车与电网能量交互的双向变流器拓扑研究

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中国电机工程学报 2012年第31期32卷 50-58,218页

作者：鲍谚姜久春张宏韬牛利勇张维戈北京交通大学电气工程学院北京市海淀区100044

针对国内外广泛关注的电动汽车与电网互动技术,对二者能量交互的接口——双向变流器进行了研究。首先分类介绍了几种典型的适用于电动汽车充放电机的电路拓扑,并对其主要特点和基本原理进行了比较和分析。在此基础上,提出了一种新颖的... 详细信息

针对国内外广泛关注的电动汽车与电网互动技术,对二者能量交互的接口——双向变流器进行了研究。首先分类介绍了几种典型的适用于电动汽车充放电机的电路拓扑,并对其主要特点和基本原理进行了比较和分析。在此基础上,提出了一种新颖的高功率因数双向单级全桥变换器(bi-directional single-phase single-stage full-bridge converter,BSS-FBC)拓扑,相比其他典型拓扑,该变换器具有效率高、功率密度高、谐波污染小、体积小、成本低、控制简单等特点。介绍了该拓扑的工作原理和设计要点,采用二重傅里叶积分方法对该拓扑进行了谐波特性分析。基于所提出的拓扑及控制方案,制作了一台功率为3.3kW的样机,通过仿真和实验验证了该变换器的优良性能。

关键词：电动汽车入网单级高频隔离双向变流器数字控制谐波分析