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571.
以徐州市区2000年和2006年土地利用基础数据为数据源,建立景观类型与土地利用类型的对应关系。将徐州市区景观划分成农业景观、园林绿地景观、居住景观、工业景观、商服公共设施景观、水体景观、交通景观和其他景观8种类型,获得2000,2006年徐州市区景观分类图。计算出景观格局指数,利用GIS的空间分析功能,对徐州市区景观格局及其变化特征进行分析。结果表明:在城市化驱动下,徐州市区农业景观主要向居住景观、工业景观转移,商服公共设施景观、居住景观和工业景观的相互转移频繁;农业景观在空间上逐渐分散,其余的景观类型呈现聚集的趋势;徐州市区呈现出景观异质性程度、斑块破碎化程度和斑块复杂化程度均加强的景观格局变化趋势。 相似文献
572.
山岳旅游地生态服务价值时空分异及其与环境因子关系——以武夷山风景名胜区为例 总被引:3,自引:0,他引:3
以山岳型旅游地武夷山风景名胜区为例,估算了风景区景观生态服务价值,分析1986年、1997年、2009年风景区景观生态服务价值时空变化特征,并运用相关分析和逐步回归分析方法对生态服务价值与环境因子的关系进行了探讨,以期揭示风景区景观生态服务价值与环境因子间的作用规律。结果表明:1.武夷山风景名胜区景观类型单位面积生态服务价值最高为水体(9 3707元/(hm2.a)),最低为裸地(354元/(hm2.a)),建设用地价值(12 000元/(hm2.a))仅高于裸地、农田、灌草等景观类型,杉木林、马尾松林、竹林、阔叶林等森林景观服务价值相差不大;2.风景区内景观生态服务价值在1986—1997年间服务价值有较大损失,在1997—2009年间得到一定程度弥补,但1986-2009年间景观生态服务价值变化呈亏损趋势,植被景观类型向建设用地的转变导致景观生态服务价值的降低;3.风景区内景观类型生态服务价值与环境因子(坡向除外)间呈现中等相关性,其中,郁闭度与生态服务价值相关系数最高(0.7**),环境因子中蓄积量与郁闭度相关系数最高(0.86**);4.植被景观生态服务价拟合结果(R2=0.7524,p<0.0001)值优于非植被景观(R2=0.5370,p<0.0001),拟合效果能较好地揭示景观类型生态服务价值与环境因子间的数量关系。 相似文献
573.
北京市杨镇一中人工湿地设计及污水处理效果 总被引:1,自引:0,他引:1
针对北京市农村地区居民居住相对分散、生活污水集中处理难度大的状况,在北京市杨镇一中,建立了经济且简便易行的用于处理污水的人工湿地。该人工湿地由地埋式一体化预处理、多级复合式人工湿地系统、景观湿地系统三部分组成。通过单元实验,对人工湿地的填料结构、植物选择、布水设计、水位调节、湿地防堵系统设计、预处理系统设计进行了创新,研究了1d、2d和3d水力停留时间对污水中有机物处理效应的影响,并开展了人工湿地基质堵塞实验、冬季保温措施研究以及人工湿地脱氮除磷效果研究。结果表明,比较而言,1d和3d的水力停留时间不利于有机物的去除,2d的水力停留时间有利于有机物的去除;人工湿地0~10m的水平距离内,0~5cm、30~35cm、60~65cm深度的基质的堵塞差异显著(n=10,p<0.05),从水平上看,在0m、2m、4m处基质的堵塞最为明显,因此,在更换人工湿地基质时,只需更换0~4m内的基质;棚膜+蒲席覆盖系统去除污水中总氮的效果要优于结冰盖系统,更适宜于北方使用;预处理系统、人工湿地系统、景观湿地系统三部分共同处理污水,优势互补,能使处理后的出水符合北京市水污染排放标准一级B限值。 相似文献
574.
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
575.
576.
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
577.
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
578.
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
579.
580.
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