Building Temporal Topology in a GIS Database to Study the Land‐Use Changes in a Rural‐Urban Environment

This article addresses the issue of linking temporal and spatial information into a GIS database structure to investigate the land‐use changes in a rural‐urban region over a thirty‐five‐year period. More specifically, it describes the application of a programming package developed to build temporal topology in an historical land‐use GIS database to efficiently perform spatiotemporal queries. The program was created within the MapInfo environment using MapBasic language. Different types of information, such as the rate of change, the relationship between the change of land use and zoning regulations, and land‐use succession were extracted from the database. A user‐friendly interface was also developed to easily address spatiotemporal queries to the database. This approach represents a flexible and performing tool for scientists and planners who need to efficiently capture essential spatiotemporal information required for geographical inquiry and decision‐making.     

Manuscript Reviewers for Volume 53

Books reviewed: Bassin, Mark, Imperial Visions: Nationalist Imagination and Geographical Expansion in the Russian Far East, 1840 – 1865 Shortridge, James R., Our Town on the Plains: J. J. Pennell's Photographs of Junction City, Kansas, 1893 – 1922 Jakle, John A. and Sculle, Keith A., Fast Food: Roadside Restaurants in the Automobile Age Boeschenstein, Walter, Historic American Towns along the Atlantic Coast McKee, Jesse O., Ethnicity in Contemporary America: A Geographical Appraisal Luciuk, Lubomyr Y., Searching for Place: Ukrainian Displaced Persons, Ottawa, and the Migration of Memory Hausladen, Gary, Places for Dead Bodies Phillips, Richard, Watt, Diane and Shuttleton, David, De‐Centering Sexualities: Politics and Representations beyond the Metropolis Goldin, Liliana R., Identities on the Move, Transnational Processes in North America and the Caribbean Basin McDonald, David A., On Borders: Perspectives on International Migration in Southern Africa Fox, Roddy and Rowntree, Kate, The Geography of South Africa in a Changing World Takeuchi, Keiichi, Modern Japanese Geography: An Intellectual History Amery, Hussein A., and Wolf, Aaron T., Water in the Middle East: A Geography of Peace Karl, Thomas R., Nicholls, Neville and Ghazi, Anver, Weather and Climate Extremes: Changes, Variations, and a Perspective from the Insurance Industry Pittman, Blair, Texas Caves     

Results from the Big Spring basin water quality monitoring and demonstration projects,Iowa, USA

Agricultural practices, hydrology, and water quality of the 267-km² Big Spring groundwater drainage basin in Clayton County, Iowa, have been monitored since 1981. Land use is agricultural; nitrate-nitrogen (-N) and herbicides are the resulting contaminants in groundwater and surface water. Ordovician Galena Group carbonate rocks comprise the main aquifer in the basin. Recharge to this karstic aquifer is by infiltration, augmented by sinkhole-captured runoff. Groundwater is discharged at Big Spring, where quantity and quality of the discharge are monitored. Monitoring has shown a threefold increase in groundwater nitrate-N concentrations from the 1960s to the early 1980s. The nitrate-N discharged from the basin typically is equivalent to over one-third of the nitrogen fertilizer applied, with larger losses during wetter years. Atrazine is present in groundwater all year; however, contaminant concentrations in the groundwater respond directly to recharge events, and unique chemical signatures of infiltration versus runoff recharge are detectable in the discharge from Big Spring. Education and demonstration efforts have reduced nitrogen fertilizer application rates by one-third since 1981. Relating declines in nitrate and pesticide concentrations to inputs of nitrogen fertilizer and pesticides at Big Spring is problematic. Annual recharge has varied five-fold during monitoring, overshadowing any water-quality improvements resulting from incrementally decreased inputs. Electronic Publication     

Influence of source region properties on scaling relations forM<0 events

Excavation induced seismic events with moment magnitudesM<0 are examined in an attempt to determine the role geology, excavation geometry, and stress have on scaling relations. Correlations are established based on accurate measurements of excavation geometry and methodology, stress regime, rock mass structure, local tectonics, and seismic locations. Scaling relations incorporated seismic moments and source radii obtained by spectral analysis, accounting for source, propagation, and site effects, and using Madariaga's dynamic circular fault model. Observations suggest that the interaction of stresses with pre-existing fractures, fracture complexity and depth of events are the main factors influencing source characteristics and scaling behaviour. Self-similar relationships were found for events at similar depths or for weakly structured rock masses with reduced clamping stresses, whereas a non-similar behaviour was found for events with increasing depth or for heavily fractured zones under stress confinement. Additionally, the scaling behaviour for combined data sets tended to mask the non-similar trends. Overall, depth and fracture complexity, initially thought as second order effects, appear to significantly influence source characteristics of seismic events withM<0 and consequently favour a non-similar earthquake generation process.     

地籍空间实体及其时空拓扑关系

从地籍实体及其静态空间关系的推导出发,讨论了地籍变更的几种类型,创造性地应用地籍实体变更事件驱动地籍空间实体及其拓扑关系的变更,并把地籍变更情况下时空发生的变化归结为碎分和复合进行处理。     

GIS线目标间拓扑关系描述的4交差模型

提出了利用连通度不变量来区分单个线目标上具有不同拓扑特性的点，进一步定义了线目标的端点集和内点集。在此基础上，建立了IR^1和IR^2中线目标间拓扑关系的基本模型。该模型能有效地表达线目标间拓扑关系的变化特性。     

基于AutoCAD二次开发的矢量地形数据检查

基于CAD的矢量地形数据是一类基本的重要的基础地理数据，其应用十分广泛，同时也是各类地理信息系统重要的数据源，其属性精度、逻辑一致性是其重要质量元素，本文论述了基于AuotoCAD二次开发实现矢量地形数据计算机自动化高效检查的技术方法。     

多尺度空间对象拓扑相似关系的表达与计算

研究了空间数据多尺度表达中,在进行模型综合时空间对象拓扑关系的表达、变化和相似性。基于空间对象之间拓扑关系的概念邻域,给出了空间对象拓扑关系相似性的定义以及在数字景观模型中拓扑关系相似性的度量方法,为空间数据的多尺度表达提供了拓扑关系分析和评价手段。     

A preliminary investigation of strong-motion data from the French Antilles

Strong-motion networks have been operating in the Caribbean region since the 1970s, however, until the mid-1990s only a few analogue stations were operational and the quantity of data recorded was very low. Since the mid-1990s, digital accelerometric networks have been established on islands within the region. At present there are thought to be about 160 stations operating in this region with a handful on Cuba, 65 on the French Antilles (mainly Guadeloupe and Martinique), eight on Jamaica, 78 on Puerto Rico (plus others on adjacent islands) and four on Trinidad.After briefly summarising the available data from the Caribbean islands, this article is mainly concerned with analysing the data that has been recorded by the networks operating on the French Antilles in terms of their distribution with respect to magnitude, source-to-site distance, focal depth and event type; site effects at certain stations; and also with respect to their predictability by ground motion estimation equations developed using data from different regions of the world. More than 300 good quality triaxial acceleration time-histories have been recorded on Guadeloupe and Martinique at a large number of stations from earthquakes with magnitudes larger than 4.8, however, most of the records are from considerable source-to-site distances. From the data available it is found that many of the commonly-used ground motion estimation equations for shallow crustal earthquakes poorly estimate the observed ground motions on the two islands; ground motions on Guadeloupe and Martinique have smaller amplitudes and are more variable than expected. This difference could be due to regional dependence of ground motions because of, for example, differing tectonics or crustal structures or because the ground motions so far recorded are, in general, from smaller earthquakes and greater distances than the range of applicability of the investigated equations.     

水文网络模型在分布式流域水文模拟中的应用

水文网络模型是地理信息系统对流域实际河网水系的一种规范化描述,它采用拓扑关系来确定流域水流的空间聚合与分散。准确地描述水文网络对成功模拟流域水流的空间分布起着至关重要的作用。水文网络数据模型的关键在于如何表达水文网络的构成要素,以及如何建立要素间的拓扑关系。本文重点阐述了水文网络模型在分布式流域水文模拟中的应用。实例研究证明,采用水文网络模型来表达流域河网水系结构有助于准确地模拟流域上水流的空间与时间分布。