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东北地区土地覆被格局变化模拟:基于CLUE-S和Markov-CA模型的对比分析

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地理科学 2024年第2期44卷 329-339页

作者：王端睿毛德华王宗明相恒星冯凯东中国科学院东北地理与农业生态研究所吉林长春130102 中国科学院大学北京100049

研究以遥感解译的东北地区2000年、2010年、2015年的土地覆被变化为基础,充分考虑自然和社会因素对土地覆被变化的影响,分别通过CLUE-S模型和Markov-CA模型对东北地区2015年和2030年土地覆被格局进行模拟,研究结果表明:通过与遥感解译的... 详细信息

研究以遥感解译的东北地区2000年、2010年、2015年的土地覆被变化为基础,充分考虑自然和社会因素对土地覆被变化的影响,分别通过CLUE-S模型和Markov-CA模型对东北地区2015年和2030年土地覆被格局进行模拟,研究结果表明:通过与遥感解译的2015年实际土地覆被类型数据对比验证,CLUE-S模型和Markov-CA模型模拟结果的总体Kappa指数分别为0.9700和0.9649,结果表明2种模型的模拟结果较为理想,CLUE-S模型的模拟精度较Markov-CA模型更高。2015—2030年东北地区草地、耕地、湿地、其他用地和水体面积呈现下降趋势,林地、人工表面面积呈现增加趋势,人地关系越发紧张。东北地区作为生态环境相对脆弱的区域需警惕不可持续的土地覆被变化,需权衡生态保护、粮食增加与基础设施建设的用地需求和协调发展。

关键词： CLUE-S模型 Markov-CA模型土地利用/覆被变化空间模拟东北地区

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《温疫论》运用下法特点及影响探析

国医论坛 2024年第4期39卷 10-13页

作者：杨广王宗明汪波贵州中医药大学第一临床医学院贵州贵阳550002 遵义市中医院贵州遵义563000

吴又可提出下法在伤寒与温病中的运用不同,其《温疫论》运用下法特点有四:重在紧扣病机,及时运用;强调明辨证候,不拘结粪一症;注重因人而异,灵活运用;注意下后调护,扶正为重。其下法特点、思想被后世医家继承和发展。戴天章明确“时疫... 详细信息

吴又可提出下法在伤寒与温病中的运用不同,其《温疫论》运用下法特点有四:重在紧扣病机,及时运用;强调明辨证候,不拘结粪一症;注重因人而异,灵活运用;注意下后调护,扶正为重。其下法特点、思想被后世医家继承和发展。戴天章明确“时疫下不厌早”;叶天士提出湿温便溏有邪,清热导滞,便硬无湿不可攻下;杨栗山针对温疫热毒炽盛提出“治法急以逐秽为第一要义”;吴鞠通在运用下法时,依据热邪轻重与津液多寡选择相应的承气汤;姜春华提出“截断扭转”法。《温疫论》中下法内容丰富,为临床下法运用提供了思想指导,值得借鉴学习。

关键词：下法吴又可《温疫论》温病学理论探讨

N-甲基芸香碱通过调控ERK通路诱导人胶质母细胞瘤细胞凋亡和自噬

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中国病理生理杂志 2024年第4期40卷 594-601页

作者：黎思源罗宇悠罗雄明王仲宇陈晖彤樊东袁星怡陈乐唐佩刘靖王宗明王欣广东药科大学基础医学院人体解剖学与组织胚胎学系广东广州510006 中山大学附属第一医院神经外科垂体瘤中心广东广州510062 广东药科大学生命科学与生物制药学院药用生物活性物质研究所广东广州510006

目的:已知红树林相关植物能够产生具有抗肿瘤活性的天然化合物。尽管这些化合物具有潜在的治疗价值,但其抗肿瘤作用的分子机制尚需阐明。本研究侧重探讨一种来源于红树林相关植物大管[Micromelum falcatum(Lour.)Tan.]的生物碱N-甲基芸... 详细信息

目的:已知红树林相关植物能够产生具有抗肿瘤活性的天然化合物。尽管这些化合物具有潜在的治疗价值,但其抗肿瘤作用的分子机制尚需阐明。本研究侧重探讨一种来源于红树林相关植物大管[Micromelum falcatum(Lour.)Tan.]的生物碱N-甲基芸香碱对人胶质母细胞瘤U87细胞的影响。方法:从大管茎皮中分离得到15种化合物。其中,N-甲基芸香碱被筛选用于评估其对U87细胞生长的抑制作用。采用划痕实验、Hoechst 33342/PI染色和蛋白免疫印迹等多种方法,研究了该化合物对细胞迁移、凋亡以及与自噬相关的蛋白的影响。结果:N-甲基芸香碱在24 h内抑制了U87细胞的迁移活动,抗凋亡蛋白Bcl-2的表达减少,促凋亡蛋白Bax的表达增加,促使U87细胞发生凋亡,同时提高了U87细胞中自噬相关蛋白LC3-II/LC3-I的比值。此外,在N-甲基芸香碱处理细胞后,发现ERK信号通路被下调。结论:N-甲基芸香碱能够诱导U87细胞的凋亡和自噬性细胞死亡,从而抑制细胞生长,这种效应似乎与ERK信号通路有关。

关键词：红树林相关植物 N-甲基芸香碱胶质母细胞瘤

Modeling potential wetland distributions in China based on geographic big data and machine learning algorithms

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International Journal of Digital Earth 2023年第1期16卷 3706-3724页

作者： Hengxing Xiang Yanbiao Xi Dehua Mao Tianyuan Xu Ming wang Fudong Yu Kaidong Feng zongming wang State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchunPeople’s Republic of China International Institute for Earth System Science Nanjing UniversityNanjingPeople’s Republic of China School of Foreign Languages Zhongnan University of Economics and LawWuhanPeople’s Republic of China College of Information and Technology Jilin Agricultural UniversityChangchunPeople’s Republic of China National Earth System Science Data Center BeijingPeople’s Republic of China

Climate change and human activities have reduced the area and degraded the functions and services of wetlands in *** protect and restore wetlands,it is urgent to predict the spatial distribution of potential *** this study,the distribution of potential wetlands in China was simulated by integrating the advantages of Google Earth Engine with geographic big data and machine learning *** on a potential wetland database with 46,000 samples and an indicator system of 30 hydrologic,soil,vegetation,and topographic factors,a simulation model was constructed by machine learning *** accuracy of the random forest model for simulating the distribution of potential wetlands in China was good,with an area under the receiver operating characteristic curve value of *** area of potential wetlands was 332,702 km^(2),with 39.0%of potential wetlands in Northeast *** features were notable,and potential wetlands were mainly concentrated in areas with 400-600 mm precipitation,semi-hydric and hydric soils,meadow and marsh vegetation,altitude less than 700 m,and slope less than 3°.The results provide an important reference for wetland remote sensing mapping and a scientific basis for wetland management in China.

关键词： Potential wetland distribution machine learning algorithms geographic big data China wetland geographic features

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燃气热水器火排燃烧点火与传火特性数值模拟

工业加热 2024年第2期53卷 17-23页

作者：牟少敏马家乐王宗明谢保江长城钻探工程有限公司北京100000 中国石油大学(华东)新能源学院山东青岛266580 江苏核电有限公司江苏连云港222000

目前燃气热水器只能在特定负荷下点火,开机恒温时间较长,用户使用体验不佳。基于Fluent软件,应用Realizable k-ε湍流模型、涡耗散概念燃烧模型、DO辐射模型及电火花点火模型,采用分段建模的方法对燃气热水器火排燃烧进行了数值模拟,发... 详细信息

目前燃气热水器只能在特定负荷下点火,开机恒温时间较长,用户使用体验不佳。基于Fluent软件,应用Realizable k-ε湍流模型、涡耗散概念燃烧模型、DO辐射模型及电火花点火模型,采用分段建模的方法对燃气热水器火排燃烧进行了数值模拟,发现火排片内部存在较大旋涡,燃气和一次空气预混效果较好;但在火排片间有明显的低温区,火焰高度差异较大,火焰稳定性较差,影响了任意负荷点火的成功率。进一步对火排燃烧器进行结构优化研究,发现采用两端点火模式,火焰的稳定时间减少32%;安装钝体和侧挡板后,在燃烧室内产生局部回流,提高了燃烧的稳定性,火焰的稳定时间相比原始结构减少16%以上,火焰高度更加均匀。研究结果对燃气热水器火排燃烧器的技术改进提供了参考。

关键词：燃气热水器火排燃烧特性数值模拟点火与传火结构优化

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外来红树无瓣海桑在广东省的空间分布研究

林业与环境科学 2024年第2期40卷 11-16页

作者：李耀南王宗明于皓赵传朋贾明明吉林建筑大学测绘与勘查工程学院吉林长春130118 中国科学院东北地理与农业生态研究所吉林长春130102

外来红树无瓣海桑Sonneratia apetala是我国红树林造林的重要树种,具有耐水浸、生长速度快、适应性强等特点。随着无瓣海桑的自然更新与扩张,其入侵风险引起社会广泛关注。为准确获取无瓣海桑分布,加强对这一外来树种的跟踪检测,研究基... 详细信息

外来红树无瓣海桑Sonneratia apetala是我国红树林造林的重要树种,具有耐水浸、生长速度快、适应性强等特点。随着无瓣海桑的自然更新与扩张,其入侵风险引起社会广泛关注。为准确获取无瓣海桑分布,加强对这一外来树种的跟踪检测,研究基于Sentinel-2卫星影像和随机森林算法,在Google Earth Engine平台下构建了2015年广东省无瓣海桑分布数据,总体精度达到96.3%。结果表明:2015年广东省无瓣海桑总面积为1704.33 hm^(2)。应用核密度分析方法发现,这一外来红树主要集中在雷州半岛西部和珠江口区域。与2020年的数据对比显示,广东省无瓣海桑的斑块数量和斑块面积均有较为显著的扩张。

关键词：无瓣海桑外来红树随机森林分类遥感监测

1971-2022年河南省水汽压与能见度的时空分布及其关联

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气象与环境科学 2024年第3期47卷 8-13页

作者：席世平夏依聪王宗明竹磊磊肖瑶王纪军中国气象局·河南省农业气象保障与应用技术重点实验室郑州450003 河南省气象服务中心郑州450003 河南省气候中心郑州450003

为探究河南省水汽压和能见度的时空分布特征和相关性,利用1971-2022年河南省118个国家级气象站的日最高水汽压和日最小能见度数据,分析了河南省年平均最高水汽压和最小能见度的时空变化特征及二者的相关性。结果表明:(1)年平均最高水汽... 详细信息

为探究河南省水汽压和能见度的时空分布特征和相关性,利用1971-2022年河南省118个国家级气象站的日最高水汽压和日最小能见度数据,分析了河南省年平均最高水汽压和最小能见度的时空变化特征及二者的相关性。结果表明:(1)年平均最高水汽压呈显著上升趋势,其气候倾向率达0.25 hPa/10a;最高水汽压在1998年发生由低到高的突变;豫中南、豫东及豫北水汽压上升最为显著;最高水汽压变化幅度大值区主要位于豫中南大部、豫西南部分县市。(2)年平均最小能见度呈显著下降趋势,其气候倾向率为-0.56 km/10a;最小能见度在2014年出现下降突变;豫西、豫西南、豫北部分县市及商丘、信阳局部能见度下降显著,变化幅度较大。(3)河南省大部分地区年平均最高水汽压与最小能见度存在显著的负相关(区域平均相关系数约为-0.41),水汽压升高(降低)易引起能见度降低(升高)。

关键词：最高水汽压最小能见度时空分布相关性分析

Comparative Study on Changes of Croplands Between North Korea and South Korea During 1990–2015

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Chinese Geographical Science 2018年第6期28卷 920-934页

作者： YU Hao ZHANG Bai wang zongming Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changch un 130102 China University of Chinese Academy of Sciences Beijing 100049 China

Studies on long-term change of cropland is of great significance to the utilization of land resources and the implementation of scientific agricultural policies. The Korean Peninsula, adjacent to China, plays an important role in the international environment of Northeast Asia. The Korean Peninsula includes South Korea and North Korea—two countries that have a great difference in their institutions and economic developments. Therefore, we aim to quantify the spatiotemporal changes of croplands in these two countries using Landsat Thematic Imager(TM) and Operational Land Imager(OLI) imagery, and to compare the differences of cropland changes between the two countries. This paper take full advantage of ODM approach(object-oriented segmentation and decision-tree classification based on multi-season imageries) to obtain the distribution of croplands in 1990 and 2015. Results showed that the overall classification accuracy of cropland data is 91.10% in 1990 and 92.52% in 2015. The croplands were mainly distributed in areas with slopes that were less than 8° and with elevations that were less than 300 m in the Korean Peninsula. However, in other region(slope > 8° or elevation > 300 m), the area and proportion of North Korea's croplands were significantly higher than that of South Korea. Croplands significantly increased by 15.02% in North Korea from 1990 to 2015. In contrast, croplands in South Korea slightly decreased by 1.32%. During the 25 years, policy shift, economic development, population growth, and urban sprawl played primary roles for cropland changes. Additionally, the regional differences of cropland changes were mainly due to different agriculture policies implemented by different countries. The achievements of this study can provide scientific guidance for the protection and sustainability of land resources.

关键词： Landsat object-oriented segmentation decision tree cropland North Korea South Korea

Characteristics of Sand Dune Pattern and Fluvial-aeolian Interaction in Horqin Sandy Land, Northeast Plain of China

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Chinese Geographical Science 2018年第4期28卷 624-635页

作者： DU Huishi wang zongming MAO Dehua College of Tourism and Geographical Science Jilin Normal University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

The interaction between fluvial and aeolian processes can significantly change surface morphology of the Earth. Taking the Horqin Sandy Land as the research area and using Landsat series satellite remote sensing images, this study utilizes geomorphology and landscape ecology to monitor and analyze the aeolian geomorphology characteristics of the Horqin Sandy Land. Results show that the sand dunes of the Horqin Sandy Land are mainly distributed on alluvial plains along the banks of the mainstream and tributaries of the Western Liao River, and the sand dune types tend to simplify from west to east and from south to north. The aeolian geomorphology coverage tend to be decreasing in the past 40 years, with an average annual change rate of 0.31%. While the area of traveling dunes decreased, the area of fixed and semi-fixed dunes increased. The fractal dimensions of various types of sand dune have all remained relatively constant between 1.07 and 1.10, suggesting that they are experiencing a relatively stable evolutionary process. There is a complex interaction between fluvial and aeolian processes of the Horqin Sandy Land, which plays a central role in surface landscape molding. Sand dunes on both sides of different rivers on the Horqin Sandy Land present certain regularity and different characteristics in terms of morphology, developmental scale, and spatial pattern. There are six fluvial-aeolian interaction modes in this area: supply of sand sources by rivers for sand dune development, complete obstruction of dune migration by rivers, partial obstruction of dune migration by rivers, influence of river valleys on dune developmental types on both sides, influence of river valleys on dune developmental scale on both sides, and river diversion due to obstruction and forcing by sand dunes. This study deepens our understanding of the surface process mechanism of the interaction between fluvial and aeolian processes in semi-arid regions, and provides a basis for researches on

关键词： fluvial-aeolian interaction riverine dune landscape evolution sand dune pattern Horqin Sandy Land