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451.
根据苏州市高新区对科技城的总体定位,以及对区内废弃宕口整治的初步设想,提出废弃宕口景观设计应以生态恢复和可持续发展为主题。通过对项目的实地勘察,经过分析提出相应的开发对策及生态设计理念,依据宕口规划、植物配置的原则,对总体布局进行功能分区,使其符合所在地域社会经济可持续发展的需要,彻底改善生态环境[1]。整个设计保留了部分宕口实景,通过改造,使原来裸露的废弃宕口变成了风景秀丽的观光带,带来了一定的景观及人文效应。 相似文献
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453.
董晔 《中国地质灾害与防治学报》2001,12(1):47-50
大连小龙街边坡原始地貌陡峭,高差45.28m,由于上覆残积土及后期在建筑施工中堆积了大量的杂填土,在地表水与地下水浸泡作用下,土体失稳,产生类似泥石流性质的滑坡,毁坏原山坡走梯及下部挡墙,造成人员、住宅及财产损失。本文在大连小龙街滑坡治理工程设计时,重点考虑了滑坡的发生机理、治理工程场地施工条件、建筑美学及原有下水管线、走梯等修复工作,采用土石方清理,滑坡前缘一、二级锚拉钢筋混凝土板墙,滑坡中部花坛及走梯,滑坡后缘一、二级钢筋混凝土柱板墙,排水工程和绿化工程六部分进行施工,效果较好。可供相似城区地质灾害治理工程参考。 相似文献
454.
GIS支持下吉林省西部地下水特征组分分布特征研究 总被引:5,自引:0,他引:5
通过使用GIS技术,论述了吉林省西部平原地区地下水特征组分如氟、铁及氨态氮、硬度和矿化度等的分布规律,并做出了水质评价图。这些组分均和人的健康密切相关,而当地居民多直接饮用这些组分浓度很高的地下潜水。经分析发现,在潜水中特征组分浓度无高于承压水,且明显超过国家标准。由于景观地球化学分异因素的影响,潜水中特征组分在西部山前丘陵-洪积平原及松辽分水岭一带的浓度较低,而在霍林河岸即从通输-乾安-大安-前郭-带低洼湿地地区较高,总体上承压水水质好于潜水。 相似文献
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Historic land use in the Chesapeake Bay drainage basin induced large fluxes of fluvial sediment to subestuarine tributaries. Stratigraphic and palaeoecologic analyses of deltaic deposits may be used to infer changes on the landscape, but are not sufficient to quantify past sediment supply. When viewed as an inverse boundary‐value problem, reconstruction of the sediment supply function may be achieved by combining deltaic sedimentation chronologies with an equation governing delta progradation. We propose that the diffusion equation is appropriate for simulating delta progradation and obtaining the sediment supply function provided a suitable diffusion constant (D) can be determined. Three new methods for estimating D are presented for the case of estuarine deltas. When the inverse boundary‐value technique was applied to Otter Point Creek, a tidal freshwater delta at the head of Bush River in upper Chesapeake Bay, D values ranged from 3763 to 6199 m2 a?1. Delta growth simulations showed a 1740–1760 initial pulse, a 1760–1780 erosive/redistributive interval, a 1780–1920 growth period, and a 1920‐present erosive/redistributive era. Coupling of simulated delta elevations with an empirical plant habitat predictive equation allowed for comparison of predicted versus actual relative habitat areas. Also, the model yielded reconstructed watershed erosion rates and stream suspended sediment concentrations that could be useful for development of water quality regulations. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
457.
Arjun M. Heimsath William E. Dietrich Kunihiko Nishiizumi Robert C. Finkel 《地球表面变化过程与地形》2001,26(5):531-552
Landscapes in areas of active uplift and erosion can only remain soil‐mantled if the local production of soil equals or exceeds the local erosion rate. The soil production rate varies with soil depth, hence local variation in soil depth may provide clues about spatial variation in erosion rates. If uplift and the consequent erosion rates are sufficiently uniform in space and time, then there will be tendency toward equilibrium landforms shaped by the erosional processes. Soil mantle thickness would adjust such that soil production matched the erosion. Previous work in the Oregon Coast Range suggested that there may be a tendency locally toward equilibrium between hillslope erosion and sediment yield. Here results from a new methodology based on cosmogenic radionuclide accumulation in bedrock minerals at the base of the soil column are reported. We quantify how soil production varies with soil thickness in the southern Oregon Coast Range and explore further the issue of landscape equilibrium. Apparent soil production is determined to be an inverse exponential function of soil depth, with a maximum inferred production rate of 268 m Ma?1 occurring under zero soil depth. This rate depends, however, on the degree of weathering of the underlying bedrock. The stochastic and large‐scale nature of soil production by biogenic processes leads to large temporal and spatial variations in soil depth; the spatial variation of soil depth neither supports nor rejects equilibrium morphology. Our observed catchment‐averaged erosion rate of 117 m Ma?1 is, however, similar to that estimated for the region by others, and to soil production rates under thin and intermediate soils typical for the steep ridges. We suggest that portions of the Oregon Coast Range may be eroding at roughly the same rate, but that local competition between drainage networks and episodic erosional events leads to landforms that are out of equilibrium locally and have a spatially varying soil mantle. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
458.
The use of the metaphors of general fitness and N-K spaces can assist in the understanding of the development of the physical landscape. Different modes of change can be viewed as different types of movement in, and distortions of, these phase spaces. Visualized in this manner landscape change can be viewed as both channelized, constrained and random. 相似文献
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460.
Dona J. Stewart 《The Professional geographer》2001,53(3):361-373
This article presents a methodology for a more detailed investigation of urban landscape change in rapidly growing cities of the less developed world beyond typical macrolevel approaches. This research is an attempt to bridge the gap between traditional landscape analysis and geographic information science (GIS). The article presents the preliminary results from a pilot project in Zamalek, Egypt, highlighting the benefits and drawbacks of the two techniques. Rarely used to study the less developed world, these techniques are utilized to assess change within a portion of Cairo's urban landscape. Large‐scale historic maps and high‐resolution satellite imagery, combined with field attribute collection, are the major data sources in this applied landscape analysis. A motivating factor in the desire to examine landscape change at such a large scale is the need to create monitoring systems for historic preservation in cities of the less developed world. 相似文献