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151.
152.
Urban land cover composition is the key factor affecting the living environment and urban ecosystem service. Based on the Google Earth Engine platform, Landsat 5/8 remote sensing image data were used to adopt the improved "Vegetation-Impervious Surface-Soil" model and linear spectral mixed decomposition method. The variation characteristics of land cover in Nur-Sudan, Almaty, Urumqi cities from 1990 to 2015 were compared and analyzed. The results show that the urban built-up area of Urumqi city expanded the largest area of the three cities from1990 to 2015, with an expansion of 349.81 km2, followed by Nur-Sultan, with a city expansion area of 158.16 km2. As the capital of Kazakhstan was relocated from Almaty to Nur-Sultan, the city of Almaty expanded the slowest during the entire period, with a total expansion of 126.23 km2. In the urban built-up area, the urban surface in Urumqi increased by 7.10% from 1990 to 2015, and the Nur-Sultan and Almaty decreased by 14.9% and 4.49%,respectively. The green space component of the built-up area, Nur-Sultan increased by 6.68% from 1990 to 2015, while Urumqi and Almaty decreased by 6.65% and 2.75%,respectively. The different surface cover patterns of cities are different for different reasons. Urumqi is mainly supported by national policies, and Almaty is known for its historical background and urban planning, while the rapid development of Nur-Sudan was affected by the relocation of Kazakhstan. 相似文献
153.
James Meikle 《Construction Management & Economics》2013,31(3):259-265
Over the last few decades, house prices in the UK have risen at a higher rate than general prices, as measured by, for example, the retail price index. Construction prices, on the other hand, tend to have risen broadly in line with general prices. Assuming the same things are being measured in each case, this implies that, over the period, the price of land, the most significant non-construction element of house prices, has risen at a faster rate than house prices and a much higher rate than construction prices. This paper reviews past price trends and concludes that not only have house prices risen faster than construction prices but also that, as a result, construction prices represent a smaller proportion of house prices. The paper also considers briefly what might be the implications if that trend continued- or if it did not. 相似文献
154.
在对西湖凹陷FHT构造岩心、钻井及分析化验资料综合研究的基础上,运用层序地层学、沉积学和测井地质学原理,通过大量的基础研究,克服了海上井少、资料不全的困难,识别了西湖凹陷PH组下层系沉积环境、沉积特征。经过分析研究,认为PH组下层系P8、P9、P10、P11沉积环境为半封闭海湾中的泻湖潮坪沉积。在平面上,预测了砂体的平面展布特征,分析了其在平面上的演化规律。纵向上,从P11到P8层,砂体逐渐向凹陷的西南扩展,规模也有所扩大,总体上反映为海进的沉积特征。 相似文献
155.
2007年10月在美国马里兰州举办了理性增长十周年(Smart Growth@10)会议。本文在回顾马里兰州理性增长十年发展历程基础上,严格审查马里兰州理性增长运动的实践成效,具体包括理性增长在土地利用变更、社区复兴、住宅偏好及选择、耕地保护、基础设施建设等领域所取得的成就和存在的不足,并总结了未来马里兰州理性增长运动进一步完善的政策建议,希望美国马里兰州的理性增长实践能够为中国未来城市规划、发展和管理的改革创新提供借鉴和启示. 相似文献
156.
随着我国经济的飞速发展,土地升值,由此引发了形形色色土地违法犯罪案件,严重影响了我国经济健康、有序的发展。笔者从现阶段我国土地违法犯罪案件的特征着手,通过对现行刑法保护土地资源现状的分析,指出其中存在的问题,进而提出防范土地犯罪的相应法律对策。 相似文献
157.
Andrew Brookes 《河流研究与利用》1987,1(1):3-16
The Danish Watercourse Law of 1982 states that major river works and maintenance procedures must be planned and undertaken with regard to water quality and the physical form of the river channel. Fluvial geomorphology is an essential component of alternative procedures of river management which work with nature rather than against it. A survey of Danish stream channels has been produced by collating data obtained from maps, field surveys and engineering documents. This indicates that 97.8 per cent of Danish watercourses have been artificially straightened and that only 2.2 per cent (880 km) have natural morphological characteristics. The density of channel works is 300 times greater than in the U.S.A. and 15 times greater than in England and Wales. It is suggested that since there are only a few naturally sinuous channels in Denmark these should be given special consideration with regard to stream management practices. Measurements undertaken at approximately 300 sites in Denmark indicate five major processes of adjustment within straightened reaches. These adjustments include degradation of the channel bed with associated bank slumping, armouring of the bed, the development of a sinuous thalweg by the deposition of sediment at low gradients, and restoration of meanders. Channel stability is related to specific stream power and the results may be useful in predicting potential adjustments following channel straightening. Deposition in natural reaches below straightened channels often obliterates pool and riffle sequences but several channel adjustments may provide a greater variability of physical habitats than the initial uniform straightened channel; their significance for the biology of the watercourse is best considered before traditional management practices are carried out to control the adjustment. 相似文献
158.
Kathrin Strebel Ulrike Rolle-Kampczyk Annegret Kindler Uwe Schlink 《The Science of the total environment》2010,408(18):3931-3942
This paper presents an investigation into spatial risk differences over small distances for the Helicobacter pylori infection in the city of Leipzig, Germany and two rural districts. A model, using Bayesian inference, was developed that adjusts the risk for individual-specific factors, and for spatial or individual over-dispersion, respectively. Additionally, the model takes into account conditional spatial autocorrelation. We found a significant positive association to the H. pylori infection risk for: “more than three children live in the household” (OR = 2.4, p = 0.001), “more persons live per sq.m than average” (OR = 1.4, p = 0.03), “home situated at main road” (OR = 1.4, p = 0.04) and “using well water” (OR = 2.3, p = 0.05). A protective effect was identified for “travelled to low prevalence region” (OR = 0.4, p < 0.0001) and “born in Germany” (OR = 0.2, p < 0.0001). Three administrative areas with significantly increased spatial risk were identified: one in the rural district and two in the city of Leipzig. The model explained 24.9% of the total deviance. Contrary to expectations, the largest part of deviance of the data was not explained by the identified significant risk factors, but by individual-specific heterogeneities. We conclude that further - so far not discussed - factors influence the risk and the spatial variation of the H.pylori infection. Furthermore, from the results we speculate about a possible impact of long-time air pollution and surface water. 相似文献
159.
Based on DEM of Qinling Mountains, used the model of the center cell and the adjacent eight cells, we calculated the surface area of Shaanxi section Qinling Mountains. The results shows that: (1) The surface area of Shaanxi section Qinling Mountains is 75 224.67 km2, which is an increase of 22.04% from the vertical projection area;(2)The relation between the difference of surface area and vertical projection area and elevation is parabolic. The altitude of 2 000 meters is the area with the largest difference between the surface area and the vertical projection area in Shaanxi section Qinling mountains;(3)Compared with the vertical projection area, the area of low mountains, medium mountains and submountains in Shaanxi section of the Qinling mountains increased by 2 301.54 km2, 6 181.67 km2 and 691.60 km2 respectively, with the growth rate of 10.68%, 18.37% and 18.25% respectively.(4)The difference between the surface area and the vertical projection area is various in different land use types. Not using land is the largest, the difference is 34%. The second is forest land which the difference is 28%, and the lawn is approximately 20%. Difference is small in farmland, other forest land, water and residents and industrial land, which is 12%, 8%, 5% and 8% in turn. 相似文献
160.
An integrated approach is presented for determining the harmonized optimal coastline from given options for large-scale coastal reclamation. The approach incorporates results from hydrodynamic, sediment transport, and water quality models and ecological impact considerations. These models predict reclamation impact on tidal flow, sediment deposition and erosion, and water quality under different scenarios. The impact on sensitive coastal ecosystems is considered indirectly in terms of the qualitative relationship to results from the sediment transport model. The analytical hierarchy process method is applied to determine the weights of various control factors and to integrate the model predictions. A sensitivity analysis is made to assess the effect on the final results of modeling errors and uncertainty in the weights assigned, and thus to enhance the reliability of decision making. Although the methodology given herein emphasizes reclamation in a bay with multifold functions, the procedure is potentially applicable to most coastal reclamation projects, except single-option schemes. An application to Deep Bay coastline is described in the companion paper. 相似文献