The dynamic coupling model and its application of urbanization and eco-environment in Hexi Corridor

This paper, taking Hexi Corridor as an example, analyzes the alternating intimidation and the dynamic evolving relation between urbanization and eco-environment in arid area of West China. We argue that the harmonious development system of the urbanization and eco-environment would go through four phases: rudimentary symbiotic phase, harmonious developmental phase, utmost increasing phase and spiral type rising phase. Throughout the four phases, the elements of the system would influence each other, coerce each other, and complete the spiral type rising process from low-grade symbiosis to high-grade harmony together. The study on Hexi Corridor shows that the urbanization level in Hexi Corridor has increased gradually from 1985 to 2003 accompanied with the fluctuations of eco-environment state. The response of eco-environment to urbanization has been evident, but lagged behind the urbanization course. At present, the harmonious development system in Hexi Corridor was in its harmonious developmental phase. However, the coupling degree has increased quickly and approached 90 yet, which is signaling that the system is about to enter the utmost increasing phase, and the ecological crisis will enter the latent period. We have found that the coupling degree can well reflect the interactive coercing and dynamic evolving situation between urbanization and eco-environment in Hexi Corridor. From the temporal change of the coupling degree, it can be concluded that urbanization sometimes needs to pay a certain cost for the damage of the eco-environment in its initial stages, but as the urbanization continues, the state of the eco-environment would be meliorated.     

Combining Sample and Census Data in Small Area Estimates: Iterative Proportional Fitting with Standard Software*

The combination of detailed sample data with less detailed but fully enumerated marginal subtotals is the focus of a wide range of research. In this article we advocate careful modeling of sample data, followed by Iterative Proportional Fitting (IPF). The modeling aims to estimate accurately the interaction or odds ratios of complex tables, which is information not contained in the marginal subtotals. IPF ensures consistency with the subtotals. We advance this work in three practical ways. First, we show that detailed small‐area estimates of both counts and proportional distributions usually gain accuracy by combining data for larger areas containing the small areas, and we illustrate the multilevel framework to achieve these estimates. Second, we find that a general classification or socioeconomic typology of the small areas is even more associated with the within‐area interactions than is membership of the larger area. Third, we show how the Statistical Package for the Social Sciences (SPSS) can be used for IPF in any number of dimensions and with any structure of constraining marginal subtotals. Throughout, we use an example taken from the 1991 U.K. Census. These data allow us to evaluate various methods combining 100 percent tabulations and the Samples of Anonymised Records.     

Impact des crues sur les bilans sédimentaires de chenaux secondaires de la Loire moyenne (France)

Volumes of sediments eroded and deposited during floods were quantified in a vegetated secondary channel of the Loire River at the study site of Bréhémont (France). The topographic survey highlights the temporal variability in filling of secondary channels. Upstream riffle of secondary channels governs sedimentary supply. In these channels, sediments show a by-passing in the lower parts and an accretion in the higher vegetated areas. The asymmetrical morphology is reinforced during both intense and moderate floods. Sedimentary accretion in the vegetated areas leads progressively to channel narrowing. To cite this article: S. Rodrigues et al., C. R. Geoscience 337 (2005).     

基于NOAA时间序列数据分析的中国西部荒漠化监测

利用1982～2000年的NOAAAVHRR10日合成时间序列数据,对中国西部干旱半干旱区的沙漠边缘及荒漠化多年动态变化进行了分析。     

Application of Remote Sensing and GIS Technology to the Study of Desertification of Arable Lands in North Shaanxi, China

The policy of the Chinese government concerning the horizontal expansion of the cultivated land through the reclamation of desert soils result in a total increase of 665. 985 km^2 during the period 1987-1999 in North Shaanxi. This increase is less than the loss in arable land by urbanization. The accelerated rate of change in agricultural areas calls for more rapid surveys of urbanization and loss of arable land. Remote sensing has a number of advantages over ground-based methods for such surveys. The multi-scale concept of remote sensing data help us study the problem in four towns. Several maps were produced to analyze the situation of urban coverage in different times. The evaluation of the status, rate and risk of urbanization are based on an accepted average of urban increase as 2% of population growth per year.     

南充市人工湿地的规划研究

通过对传统污水处理的生化二级处理系统与人工湿地污水处理系统分析和比较，可以看出污水处理厂具有投资大、运行成本费高、并难以解决水质“富营养化”的缺点，而人工湿地污水处理系统具有投资少、运行成本低、出水质量好的优点。根据南充城市化进程的具体形势，提出在规划和建设生态城市方案中，建设人工湿地污水处理系统的设想，并就人工湿地的规模、区位选择、活水公园设计、预期效益分析等问题进行了详细的论证和阐述。     

提高农村城镇化质量的若干思考

文章论述了农村城镇化质量的提高与农村经济的发展密切相关。经济兴旺,城镇才能兴旺;经济水平提高,城镇化质量才能提高。同时,要以人为本,完善城镇体系规划和镇区规划,构建农村城镇化质量测评指标体系,创建农村社会保障制度。     

西部山区交通线路的泥石流灾害及减灾对策

全面总结了西部山区交通线路的泥石流问题,探讨了交通线路泥石流的特点、分布及其危害现状。在掌握了泥石流特征的基础上,进一步探讨了既有线路、在建线路和拟建线路所采取的不同防灾减灾对策,并提出了山区交通线路泥石流防灾工程建设应该进一步深入研究的问题,为西部山区线路建设中的防灾、减灾工作指明了方向。     

软土地区基坑工程环境影响及其保护实例分析

以基坑工程为背景,针对上海外环隧道浦西暗埋段的大型超深基坑工程的主要环境保护问题,对基坑开挖引起的主要管线和建筑物的沉降、跟踪注浆保护措施及其效果进行了分析.实测数据表明,基坑开挖使周围建筑物和管线会产生较大的沉降速率和沉降量,尤其是降低深层承压水使远处的建筑物产生了不容忽视的均匀下沉.实践证明,采取预注浆与跟踪注浆相结合的保护措施,可以有效地减小基坑开挖对周围环境的影响.     

白兰高速公路沿线黄土场地震陷区判定与评价

采用DSD 160型电磁式振动三轴试验系统,通过对甘肃白银—兰州高速公路(国道109线)沿线黄土的震陷试验,探讨了该场地黄土在动荷载作用下的震陷特性。利用黄土震陷灾害预测方法和该地区黄土场地地震危险性分析结果,对该公路沿线黄土场地的震陷区进行了判定和评价。这些研究结果可作为该高速公路工程进行抗震设计和地震变形分析的基本依据,对黄土地区其它工程也有一定的参考价值。