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101.
黄河源区玛多县土地利用/覆被及景观格局变化的遥感分析 总被引:6,自引:3,他引:3
采用了黄河源地区1977、1990及2003年MSS、TM的3个时相遥感影像,通过人机交互的解译与GIS的空间分析,提取了玛多县3个时期的土地利用/覆被信息。分析了玛多县各地类的数量变化和空间变化特征。另外对景观生态空间分布格局,利用FRAGSTATS软件对玛多县景观级别的动态特征进行了分析。结果表明:玛多县的土地利用/覆被类型以草地为主,占全区总面积77.93%;退化现象十分严重,主要是草地覆盖度的降低以及草地沙化;景观破碎化程度在前期呈下降趋势,而后期呈上升趋势,景观斑块形态越来越偏离规则而变得复杂、多样。 相似文献
102.
中国西部生态脆弱地区景观生态位的时空差异——以陕北延安地区为例 总被引:1,自引:1,他引:0
In this study, we attempt to put forward a conception of landscape ecological niche, enlightened by international scholars on extending the ecological niche theory from spatial niche to functional niche. That is helpful for comprehensively appraising landscape spatial patterns and ecological functions, also, presents a new method for analyzing landscape features from multidimensional aspects. The practice process is demonstrated by taking Yan’an region in northwestern China as a case. Firstly, the indices system including spatial attribute and functional attribute is established for assessing landscape ecological niche. Additionally, two-dimensional figures are drawn for comparing the spatio-temporal features of landscape ecological niche in 1987 and 2000 among the 13 administrative counties. The results show that from 1987 to 2000, towards Yan’an region, spatial attribute value of landscape ecological niche changes from 1.000 to 1.178 with an obvious increment, and functional attribute value changes from 0.989 to 1.069 with a little increment, both of which enhance the regional landscape ecological niche. Towards each county, spatial attribute value of landscape ecological niche increases to different extent while functional attribute value changes dissimilarly with an increment or a decrement. 相似文献
103.
基于场所依赖的旅游地景观设计 总被引:1,自引:0,他引:1
旅游地景观设计中,遵从自然、因地制宜、源于文化、考虑市场、适度设计、注重社区、人性设计等理念已深入人心。但事实上将这些理念付诸实践后,并没有很好地提高游客的回头率和忠诚度。因此,应将场所依赖理论作为一种新理念引入旅游地景观设计,从指导思想、前期调查、景观设计到整体评估全程运用该理论,以提高游客的重游率和忠诚度。 相似文献
104.
There are various factors governing the spatial and temporal variability of soil water storage including soil properties, topography and vegetation. Some factors act locally, whereas others act nonlocally, which means that a factor measured at one location has effect on soil water storage at another location. The objective of this study was to examine the effects of local and nonlocal controls of soil water storage in a hummocky landscape using cyclical correlation analysis. Soil water storage, soil properties and terrain indices were measured along a 128‐point transect of 576 m long from the semiarid, hummocky, prairie pothole region of North America. There are large coefficients of determination (r2) between soil water storage and sand content (r2 = 0.32–0.53), organic carbon content (r2 = 0.22–0.56), depth to carbonate layer (r2 = 0.13–0.63), wetness index (r2 = 0.25–0.45) and other variables at the measurement scale at different times, indicating strong local effects from these variables. The correlation coefficients were also calculated by physically shifting the spatial series of soil water storage with respect to that of controlling factors. The shifting improves the correlation between the spatial series, and the length of shifting indicated the difference in the response of soil water to its controlling factors. For example, the value of r2 increased more than eightfold (r2 = 0.47–0.64) after shifting the spatial series of soil water storage by 54 m, almost equal to the average length of existing slope, compared with the very weak correlation (r2 = 0.02–0.08) at the measurement scale. This indicated the nonlocal effect from the relative elevation. The identification of nonlocal effects from factors improves the prediction of soil water storage. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
105.
对张家界风景区进行1/25000遥感地质调查,解译出1031条线性构造,经野外验证可靠性达85%,新确认该区存在北北东向褶皱,提出了该区经历了两次以上的褶皱构造运动的新认识。认为北北东和北东东向构造是该区的基本构造骨架,设计了区域性印支期和张家界风景区印支期、燕山早期、燕山晚期四种应力场模型,采用有限单元法进行构造应力场反演计算,所获结果与野外调查结果吻合。认为砂岩峰林地貌是泥盆纪石英砂岩处于宽缓向斜扬起端及后期背斜叠加使地层趋于水平的部位才利于砂岩峰柱的稳定形成,多次构造应力作用产生的高角度裂隙有利于峰林地貌的造型,挽近时期地壳抬升是峰林地貌形成的动力。 相似文献
106.
The Southern Alps are the topographic expression of late Cenozoic (<8 Ma ago) uplift of the crust of the leading edge of the Pacific plate in South Island, New Zealand. New fission track data on the basement exposed in the Southern Alps quantify the age, amount, and rate of rock uplift, and in combination with geomorphic parameters permit the construction of a new model of the geomorphic evolution of the Southern Alps. The model emphasizes the development over time and space of rock uplift, mean surface elevation, exhumation of crustal section, and relief. The earliest indications of mean surface uplift are between 4 and 5 Ma ago at the Alpine Fault. Mean surface uplift, which lagged the start of rock uplift, propagated southeastward from the Alpine Fault at a rate of 30 km/Ma. By about 4 Ma ago, exhumation had exposed greywacke basement adjacent to and east of the entire 300 km long central section of the Alpine Fault. At 3 Ma ago, greenschist was exposed in the southern parts of the Southern Alps near Lake Wanaka, and since then has become exhumed along a narrow strip east of the Alpine Fault. The model infers that amphibolite grade schist has been exhumed adjacent to the Alpine Fault only in the last 0·3 Ma. The age of the start of rock uplift and the amount and rate of rock uplift, all of which vary spatially, are considered to be the dominant influences on the development of the landscape in the Southern Alps. The Southern Alps have been studied in terms of domains of different rock uplift rate. At present the rate of rock uplift varies from up to 8–10 mm/a adjacent to the Alpine Fault to 0·8–1·0 mm/a along the southeastern margin of the Southern Alps. This spectrum can be divided into two domains, one northwest of the Main Divide where the present rock uplift rates are very high (up to 8–10 mm/a) and exceed the long-term value of 0·8–1·0 mm/a, and another to the southeast of the Main Divide where the long-term rate is 0·8–1·0 mm/a. A domain of no uplift lies immediately to the east of the Southern Alps, and is separated from them by a 1·0–1·5 km step in the basement topography. We argue that this spatial sequence of uplift rate domains represents a temporal one. The existing models of the geomorphic development of the Southern Alps—the dynamic cuesta model of J. Adams and the numerical model of P. Koons—are compared with the new data and evolutionary model. Particular constraints unrealized by these two earlier models include the following: the earlier timing of the start of rock uplift of the Southern Alps (8 Ma ago); the spatial variation in the timing of the start of rock uplift (8 Ma ago to 3 Ma ago); the lower long-term rock uplift rate (0·8–1·0 mm/a) of the Southern Alps for most of the late Cenozoic; the lag between the start of rock uplift and the start of mean surface uplift; and the patterns of the amounts of late Cenozoic rock uplift and erosion across the Southern Alps. 相似文献
107.
108.
109.
In this study, we attempt to put forward a conception of landscape ecological niche, enlightened by international scholars on extending the ecological niche theory from spatial niche to functional niche. That is helpful for comprehensively appraising landscape spatial patterns and ecological functions, also, presents a new method for analyzing landscape fea-tures from multidimensional aspects. The practice process is demonstrated by taking Yan’an region in northwestern China as a case. Firstly, the indices system including spatial attribute and functional attribute is established for assessing landscape ecological niche. Additionally, two-dimensional figures are drawn for comparing the spatio-temporal features of landscape ecological niche in 1987 and 2000 among the 13 administrative counties. The results show that from 1987 to 2000, towards Yan’an region, spatial attribute value of landscape ecological niche changes from 1.000 to 1.178 with an obvious increment, and functional attribute value changes from 0.989 to 1.069 with a little increment, both of which enhance the regional landscape ecological niche. Towards each county, spatial attribute value of landscape eco-logical niche increases to different extent while functional attribute value changes dissimilarly with an increment or a decrement. 相似文献
110.
REN Zhiyuan WANG Lixia 《地理学报(英文版)》2007,17(4):479-486
In this study, we attempt to put forward a conception of landscape ecological niche, enlightened by international scholars on extending the ecological niche theory from spatial niche to functional niche. That is helpful for comprehensively appraising landscape spatial patterns and ecological functions, also, presents a new method for analyzing landscape features from multidimensional aspects. The practice process is demonstrated by taking Yan'an region in northwestern China as a case. Firstly, the indices system including spatial attribute and functional attribute is established for assessing landscape ecological niche. Additionally, two-dimensional figures are drawn for comparing the spatio-temporal features of landscape ecological niche in 1987 and 2000 among the 13 administrative counties. The results show that from 1987 to 2000, towards Yan'an region, spatial attribute value of landscape ecological niche changes from 1.000 to 1.178 with an obvious increment, and functional attribute value changes from 0.989 to 1.069 with a little increment, both of which enhance the regional landscape ecological niche. Towards each county, spatial attribute value of landscape ecological niche increases to different extent while functional attribute value changes dissimilarly with an increment or a decrement. 相似文献