干旱荒漠区土地利用方式快速转变对土壤入渗性能的影响   总被引：4，自引：1，他引：3  

张润霞  赵学勇  李晶  吕文强  柴媛媛  岳红琴 《中国沙漠》2020,40(4):146-153

研究不同土地利用类型下土壤入渗及其影响因素,有助于城市土地利用管理及径流调节。以快速城市化的兰州新区6种土地利用类型为例,利用圆盘入渗仪,对土壤水分入渗过程进行了实地测量,并利用主成分分析对影响因素进行研究。结果表明：城市化过程中土地利用变化使土壤砂粒和容重增加,总孔隙度和饱和含水量降低;待建地和人工林地的土壤入渗参数值均低于其他土地利用类型。土壤入渗率与有机质含量、总孔隙度、饱和含水量、粉粒含量正相关,与容重和砂粒、黏粒含量负相关。城市化过程中土地利用类型向待建地的转变改变了土壤理化性质及土壤水分入渗能力。  相似文献   

Analysis of city centrality based on entropy weight TOPSIS and population mobility: A case study of cities in the Yangtze River Economic Belt     

罗静  陈四云  孙璇  朱媛媛  曾菊新  陈广平 《地理学报(英文版)》2020,30(4):515-534

Based on statistical data and population flow data for 2016,and using entropy weight TOPSIS and the obstacle degree model,the centrality of cities in the Yangtze River Economic Belt(YREB)together with the factors influencing centrality were measured.In addition,data for the population flow were used to analyze the relationships between cities and to verify centrality.The results showed that:(1)The pattern of centrality conforms closely to the pole-axis theory and the central geography theory.Two axes,corresponding to the Yangtze River and the Shanghai-Kunming railway line,interconnect cities of different classes.On the whole,the downstream cities have higher centrality,well-defined gradients and better development of city infrastructure compared with cities in the middle and upper reaches.(2)The economic scale and size of the population play a fundamental role in the centrality of cities,and other factors reflect differences due to different city classes.For most of the coastal cities or the capital cities in the central and western regions,factors that require long-term development such as industrial facilities,consumption,research and education provide the main competitive advantages.For cities that are lagging behind in development,transportation facilities,construction of infrastructure and fixed asset investment have become the main methods to achieve development and enhance competitiveness.(3)The mobility of city populations has a significant correlation with the centrality score,the correlation coefficients for the relationships between population mobility and centrality are all greater than 0.86(P<0.01).The population flow is mainly between high-class cities,or high-class and low-class cities,reflecting the high centrality and huge radiating effects of high-class cities.Furthermore,the cities in the YREB are closely linked to Guangdong and Beijing,reflecting the dominant economic status of Guangdong with its geographical proximity to the YREB and Beijing's enormous influence as the national political and cultural center,respectively.  相似文献   

China’s rural revitalization and development: Theory,technology and management     

Liu  Yansui  Zang  Yuzhu  Yang  Yuanyuan 《地理学报(英文版)》2020,30(12):1923-1942

Journal of Geographical Sciences - The urban-rural transformation from dichotomy to integration is a gradual process. Like rural areas in many countries, Chinese rural society is experiencing a...  相似文献   

中国海洋上空细粒子气溶胶与短寿命痕量气体的时空关系     

徐彬仁  魏瑗瑗  张晗  宋毅  杨支中 《遥感学报》2020,24(2):173-181

定量分析气溶胶与痕量气体之间的时空变化关系有助于进一步研究气粒转化。本文采用2006年—2015年MODIS气溶胶光学厚度(AOD)、细粒子模态比(FMF)和OMI痕量气体(SO_2、NO_2和HCHO)数据,对黄海、东海和南海区域上空的细粒子气溶胶与痕量气体进行定量分析。先对气溶胶和痕量气体作均值分析发现:AOD_(fine)、SO_2、NO_2和HCHO的均值在黄海、南海、东海均依次减小;再对气溶胶对痕量气体的敏感度分析发现:黄海地区的AOD_(fine)对SO_2最敏感,敏感度为0.424,这与中国东部沿海城市的人为排放有关;而东海和南海地区对HCHO的敏感度较高,依次为0.664和0.545,主要受东南亚和中国南方地区生物质燃烧影响。最后,对3个区域的气溶胶与痕量气体按季节作相关性分析发现:黄海地区AOD_(fine)在夏秋两季与SO_2的相关性较强(R0.5),主要由于夏秋两季的温湿度大,利于发生气—粒转化;东海地区夏季HCHO与AOD_(fine)相关性较明显(R=0.57);南海春季HCHO与AOD_(fine)相关性较好(R=0.57),呈现出区域与季节性的变化。最终发现,气溶胶与痕量气体随着时空变化存在相关关系。  相似文献   

川西坳陷彭州地区雷口坡组天然裂缝发育特征与形成期次     

夏宇  邓虎成  王园园  何建华  解馨慧  滕娟 《海相油气地质》2021,26(1):81-89

利用野外露头、岩心、薄片及地球化学等资料对四川盆地川西坳陷彭州地区雷口坡组天然裂缝发育特征及形成期次开展了研究.研究区宏观裂缝按成因可划分构造裂缝和和非构造裂缝,构造裂缝包括张性裂缝、剪性裂缝和破碎状裂缝,非构造裂缝主要为风化网状裂缝.宏观裂缝以构造裂缝为主,主要为剪性裂缝和张性裂缝,其中的垂直裂缝、高角度裂缝的发育密...  相似文献   

关于山东省地热尾水回灌试验的应用研究   总被引：1，自引：0，他引：1       下载免费PDF全文

崔圆圆 《山东国土资源》2019,35(7):64-71

为解决地热水开采利用过程中造成诸如水位下降、热流体排放引起的热污染和化学污染等问题,通过开展地热尾水回灌试验研究,认为在开采深层的地下热水资源的同时,必须进行人工的回灌补源,山东省通过在德州、东营、济南等地开展地热尾水回灌试验工作,效果显著。  相似文献   

桂枝法联合盐酸多奈哌齐治疗血管性痴呆30例临床观察          下载免费PDF全文

王启芝  陈炜  李媛媛 《应用海洋学学报》2019,35(8):1-3

目的：观察桂枝法联合盐酸多奈哌齐治疗血管性痴呆的临床疗效。方法：采用单盲、随机、平行对照试验的设计方法,将60例血管性痴呆患者分为治疗组和对照组,每组各30例。对照组采用盐酸多奈哌齐治疗,治疗组在对照组的基础上加用桂枝法化裁的阳化汤治疗。观察治疗前后2组患者的简易智能量表（MMSE）、日常生活功能（ADL）评分的变化。结果：治疗后治疗组的显效率和总有效率分别为36.7%和80.0%,对照组分别为26.7%和63.3%,2组比较,差异有统计学意义（P<0.05）;且治疗组治疗后MMSE和ADL评分均明显高于对照组（P<0.05）。结论：桂枝法联合盐酸多奈哌齐治疗血管性痴呆效果显著,优于单用盐酸多奈哌齐治疗。  相似文献   

Molecular phylogeny of the genus Clibanarius(Decapoda: Anomura: Diogenidae) based on mitochondrial and nuclear DNA sequences     

LI Wenjie  CHENG Jiao  HUI Min  SHA Zhongli 《海洋湖沼学报（英文）》2019,(5):1686-1697

Clibanarius , a genus of hermit crabs, is one of the most diverse genera within Diogenidae. However, studies on the phylogeny within Clibanarius is very limited. We reconstruct the molecular phylogeny of the genus Clibanarius based on two mitochondrial (16S rRNA and COI) and two nuclear protein-coding (NaK and PEPCK) genes using a multigene phylogenetic approach. Eleven selected Clibanarius species from the Indo-West Pacifi c are analyzed and the Bayesian and maximum likelihood analyses produced identical results in topology. Results suggest that C . rutilus and C . infraspinatus are more closely related to each other than to C . snelliusi , and C . striolatus shows a close relationship to C . longitarsus . The close association of C . merguiensis with C . englaucus and C . humilis is strongly supported by the divergence of C . virescens from them. Our phylogenetic results contradict the morphological classifi cation scheme proposed for Clibanarius and indicate that the relative length of dactyls and propodi is not phylogenetically signifi cant in Clibanarius . In addition, we speculate that the morphological characteristic of the median cleft of the telson might be phylogenetically important for Clibanarius .  相似文献   

基于深度学习的钨钼找矿靶区预测方法研究     

蔡惠慧  朱伟  李孜轩  刘园园  李龙斌  刘畅 《地球信息科学学报》2019,21(6):928-936

随着矿产勘查工作由浅部矿向深部隐伏矿、由易识别矿向难识别矿发展,找矿难度日益增大,地质专家越来越重视新理论、新方法、新技术的应用。深度学习作为人工智能的前沿领域/技术,对于实现矿产资源预测“智能化预测评价”具有得天独厚的优势。本文以陕西省镇安县西部钨钼矿集区单元素化探异常原始数据为基础,提出了基于深度学习的钨钼矿产评价方法。该方法以归一化地球化学数据作为模型训练数据,通过深度学习中深度自编码网络方法实现异常值提取进而识别重点成矿有利地段,实现矿产资源找矿远景区定性预测。研究结果表明,在对957条单元素化探异常原始数据分类且做好模型标签后,整个过程在计算机的“黑盒子”中自动完成学习和预测,相较于传统预测研究方法,本文方法具有自动化程度高和客观性强的特征。此外,本文利用已知矿点构建训练数据集,采用随机森林方法对预测区进行矿产资源找矿靶区预测圈定,为进一步缩小找矿靶区范围提供科学依据。  相似文献   

Inpho交互式方位角定义在ADS影像生产中的应用与研究     

孙畅  高园园  阳俊 《测绘与空间地理信息》2019,42(2):222-224

目前,Inpho全数字摄影测量系统针对航空三线阵影像具有较为成熟的处理流程。但是随着摄区环境和飞行成本要求的不断提高,航线方向不再局限于坐标轴方向,斜飞模式逐渐增多。本文在Inpho系统DOM影像制作原理的基础上,对比研究交互式方位角定义在ADS影像生产中的普遍适用性,进一步优化Inpho系统针对ADS数据的解决方案。  相似文献