Vegetation geo-climatic zonation in the rocky mountains,Northern Utah,USA     

Antonin Kusbach  Helga Van Miegroet  Janis L. Boettinger  James N. Long 《山地科学学报》2014,11(3):656-673

We developed a vegetation geo-climatic zonation incorporating the zonal concept, gradient and discriminant analysis in Wasatch Range, northern Utah, USA. Mountainous forest ecosystems were sampled and described by vegetation, physiographic features and soil properties. The Snowpack Telemetry and National Weather Service Cooperative Observer Program weather station networks were used to approximate the climate of sample plots. We analysed vegetation and environmental data using clustering, ordination, classification, and ANOVA techniques to reveal environmental gradients affecting a broad vegetation pattern and discriminate these gradients. The specific objective was to assess and classify the response of the complex vegetation to those environmental factors operating at a coarse-scale climatic level. Ordination revealed the dominant role of regional, altitude-based climate in the area. Based on vegetation physiognomy, represented by five tree species, climatic data and taxonomic classification of zonal soils, we identified two vegetation geo-climatic zones： （1） a montane zone, with Rocky Mountain juniper and Douglas-fir; and （2） a subalpine zone, with Engelmann spruce and subalpine fir as climatic climax species. Aspen was excluded from the zonation due to its great ecological amplitude. We found significant differences between the zones in regional climate and landformgeomorphology/soils. Regional climate was represented by elevation, precipitation, and air and soil temperatures; and geomorphology by soil types. This coarsescale vegetation geo-climatic zonation provides a framework for a comprehensive ecosystem survey, which is missing in the central Rocky Mountains of the United States. The vegetationgeoclimatic zonation represents a conceptual improvement on earlier classifications. This framework explicitly accounts for the influence of the physical environment on the distribution of vegetation within a complex landscape typical of the central Rocky Mountains and in mountain ranges elsewhere.  相似文献   

我国专题地图集发展与趋势分析     

方国武 《测绘与空间地理信息》2014,(10):230-233

专题地图集伴随着社会经济变革而发展,其服务功能已经扩大到政府决策、经济建设和民众生活等领域,在当代社会生活中发挥了越来越重要的作用。文章分析了新中国成立以来专题地图集发展过程与历史趋势,探讨了新时期专题地图集选题思想和设计理念的变化。  相似文献   

三维技术辅助设计地下管道内套新管的应用     

王涛  张毅  徐莹 《测绘科学技术学报》2014,(5)

既有管道由于自身弯曲和多处沉降导致其三维模型十分复杂,常用的三维管道设计软件不可用,若以测量的纵断面图为依据进行平面层次的设计则存在极大的不可靠性,因而只能利用计算机三维图形技术解决。这里研究采用三维技术辅助既有地下给排水管道内套新管的设计,用三维碰撞检测算法来趋近获取最大管径,并采用基于四元数的球面线性插值法进行三维圆弧的拟合,从而实现对复杂管道的三维建模。采用基于三角形单元的碰撞检测方法,具有简便、适用的特点。基于高效三维引擎Open Scene Graph开发了三维建模及碰撞检测演示软件并对某设计项目进行察看、验证,证实了此方法的正确性。  相似文献   

Descriptions of four new species of the genus Reticunassa Iredale, 1936 (Gastropoda: Nassariidae) from the northeastern coast of Taiwan Island and the South China Sea     

Shuqian Zhang  Suping Zhang  Chih-Yeh Lee 《海洋学报(英文版)》2022,41(8):74-77

In the present study, four new species of the genus Reticunassa Iredale, 1936 collected from Chinese waters are described and illustrated. Reticunassa hugokooli sp. nov., Reticunassa jungi sp. nov. and Reticunassa aureolineata sp. nov. were collected from the northeastern coast of Taiwan Island, whereas Reticunassa fuscofasciata sp. nov. was collected from the northeastern coast of Taiwan Island and the South China Sea. The four new species can be distinguished conchologically from other congeners mainly in protoconch, shell shape, sculpture, and coloration. These findings demonstrate that the biodiversity of this group in China might be largely underestimated.  相似文献   

Spatial distribution and the scale effect of influencing factors of specialized and sophisticated enterprises that produce new and unique products in the Yangtze River Delta region: Based on the buffer and MGWR analyses北大核心CSCD     

丁建军  胡定国  冷志明 《地理科学进展》2023,(11):2099-2112

High-quality cultivation of specialized and sophisticated enterprises that produce new and unique products is an important starting point for consolidating the security foundation of China's industrial chain and supply chain. Using buffer zone analysis and the multi-scale geographically weighted regression (MGWR) model, this study explored the spatial distribution of specialized and sophisticated enterprises that produce new and unique products in the Yangtze River Delta region and influencing factors in 2021. The study found that: 1) Spatially, Shanghai is the main area where specialized and sophisticated enterprises that produce new and unique products are concentrated, followed by provincial capitals and cities on the coast and along rivers; The overall composition of the industry is unbalanced, and the real economic industries such as machinery and equipment manufacturing and high-tech manufacturing account for a relatively high proportion, but there are differences in different regions. 2) In terms of spatial agglomeration, differences between circles and the scale effect are obvious. Within each province, the spatial distribution of specialized and sophisticated enterprises that produce new and unique products in different cities is uneven. Region-wide, the overall spatial distribution pattern of "one pole and multiple cores" is evident. Shanghai is the main agglomeration area for these enterprises, and the provincial capital cities and cities that are the regional economic centers are the secondary agglomeration areas of these enterprises. 3) The four dimensions of influencing factors—physical geography, government, market, and society—have a scale effect on the spatial distribution of specialized and sophisticated enterprises that produce new and unique products. The degree of land development acts at a small scale, which is a local variable, and shows a large difference in the impact on the spatial distribution of these enterprises across the region. Factors such as elevation, government-business relationship, degree of marketization, number and scale of enterprises, degree of openness, logistics development level, and innovation environment are global variables, and except that the degree of marketization and the number of enterprises have a significant negative impact on the spatial distribution of these enterprises, the impact of all other factors is significantly positive. The research results can provide support for the optimization of the layout of new special expertise enterprise space in the Yangtze River Delta region, in order to provide reference for the formulation of new special expertise policies and industrial planning. © 2023, Editorial office of PROGRESS IN GEOGRAPHY. All rights reserved.  相似文献   

声景学及其在旅游地理研究中的应用   总被引：2，自引：0，他引：2  

刘爱利  胡中州  刘敏  邓志勇  姚长宏 《地理研究》2013,32(6):1132-1142

声音是旅游者旅游体验的活动构成要素之一,也是强化旅游者对旅游地地方感知的重要内容,对于塑造旅游者完整深刻的旅游体验具有重要意义。从旅游地理研究的现状来看,在旅游资源开发利用、旅游产品包装设计、旅游设施空间配置、旅游形象塑造构建、目的地营销拓展等方面,研究者普遍关注了旅游系统中的视觉要素,对听觉、嗅觉、触觉等其他要素却关注得较少。基于此,在对旅游系统中声音要素进行重要性分析的基础上,将声景学及其相关理念引入旅游研究的范畴,为研究旅游系统中与声音相关的现象和关系提供了新的视角,并指出了拓展现有旅游地理研究的一个重要方向。声景学的引入,对完善和深化旅游地理研究具有重要意义。  相似文献   

Regional runoff prediction through aggregation of first-order hydrological process knowledge: a case study     

《水文科学杂志》2013,58(6):1021-1038

Abstract

The dominant processes concept was used to develop a regionally applicable rainfall—runoff model. The first-order runoff processes are identified through a combination of field investigations, physico-geographical analysis of the research area, the Alzette River basin in the Grand-Duchy of Luxembourg, and discharge data series analysis. Lithology appeared to be the major source of discrepancy in hydrological behaviour over the total area. As a result, the hydrological behaviour of each lithological substratum was characterized and conceptualized into a parsimonious model structure. The runoff signals were calibrated against the hourly-recorded discharge series of eight sub-basins, with parameter sensitivity and correlation analysis outlining the need for minor corrections to the model structure. Validation against another set of 10 sub-basins showed good results for the regional parameter set, with an average loss in efficiency (R_eff) of 0.04, compared to the reference model, with a mean R_eff of 0.79. Due to an up-scaling effect, inducing variations in the dominance of particular runoff processes, some anomalies were found in the performance of individual runoff characteristics. In this respect, limiting the application of the model to a certain spatial scale gives a high reliability of the prediction of the dynamics of hourly runoff in ungauged basins within the study area.  相似文献   

New lumped-mass-stick model based on modal characteristics of structures: development and application to a nuclear containment building     

Hwasung Roh  Huseok Lee  Jong Seh Lee 《地震工程与工程振动(英文版)》2013,12(2):307-317

In this study, a new lumped-mass-stick model (LMSM) is developed based on the modal characteristics of a structure such as eigenvalues and eigenvectors. The simplified model, named the "frequency adaptive lumped-massstick model," hasonly a small number of stick elements and nodes to provide the same natural frequencies of the structure and is applied to a nuclear containment building. To investigate the numerical performance of the LMSM, a time history analysis is carried out on both the LMSM and the finite element model (FEM) for a nuclear containment building. A comparison of the results shows that the dynamic responses of the LMSM in terms of displacement and acceleration are almost identical to those of the FEM. In addition, the results in terms of floor response spectra at certain elevations are also in good agreement.  相似文献   

中国南海蓝泥瓷海星(棘皮动物门:瓷海星科)新纪录     

张睿妍  王小谷  周亚东  鹿博  王春生 《海洋学报(英文版)》2018,37(10):185-189

瓷海星科是一类深海底栖海星，广泛分布于全球大洋深海中。其模式种蓝泥瓷海星（Porcellanaster ceruleus Wyville Thomson 1878）具有全球分布性与多态性。本文报道了该物种在中国海的首次记录。2015年6月6日，在向阳红10号执行的南海底栖生物调查航次中，于C₁₉站位（10.15°N，110.03°E；水深1400m）由三角形拖网采集到海星一只，经鉴定为蓝泥瓷海星。本文提供了该样品的形态描述与细节照片，讨论了其与该种模式样品的共同形态特征及个体差异，并总结了蓝泥瓷海星的全球分布记录。该种在中国海的首次发现，进一步拓展了其地理分布范围。  相似文献   

面向新经济的测绘工程专业改造升级路径探讨     

阎波杰  林棋  王库  张建霞  李进强  秦艳芳 《测绘与空间地理信息》2020,(2):12-16,20

针对传统测绘工程专业难以适应当前新经济环境,需要进行改造升级的现状,本文以闽江学院测绘工程专业为研究对象,依托现有测绘工程、地理信息科学和导航工程等3个专业,通过合理联动、适时修改测绘工程专业的教学大纲与教学内容,将地理信息科学和导航工程专业的相关教学资源融入测绘工程专业,建立以地理学、计算机科学与技术、测绘科学与技术为主线的现代测绘工程课程体系。以现有的"测绘地理信息专业群"为基础,构建了以地方特色产业发展和需要为导向、学科交叉互补的新型学科发展体系,提出了测绘工程专业多学科交叉复合改造的具体途径与方式。最后,建立了基于测绘工程专业改造升级的无人机遥感监测与应急测绘应用新方向并形成新的课程体系,以期为新经济环境下测绘工程专业人才的培养、学科发展、教学管理等提供参考。  相似文献