The Dynamics of the Tel Aviv Morphology

Fractal Modeling and Fractal Dimension Description of Urban Morphology

The conventional mathematical methods are based on characteristic length, while urban form has no characteristic length in many aspects. Urban area is a scale-dependence measure, which indicates the scale-free distribution of urban patterns. Thus, the urban description based on characteristic lengths should be replaced by urban characterization based on scaling. Fractal geometry is one powerful tool for the scaling analysis of cities. Fractal parameters can be defined by entropy and correlation functions. However, the question of how to understand city fractals is still pending. By means of logic deduction and ideas from fractal theory, this paper is devoted to discussing fractals and fractal dimensions of urban landscape. The main points of this work are as follows. Firstly, urban form can be treated as pre-fractals rather than real fractals, and fractal properties of cities are only valid within certain scaling ranges. Secondly, the topological dimension of city fractals based on the urban area is 0; thus, the minimum fractal dimension value of fractal cities is equal to or greater than 0. Thirdly, the fractal dimension of urban form is used to substitute the urban area, and it is better to define city fractals in a two-dimensional embedding space; thus, the maximum fractal dimension value of urban form is 2. A conclusion can be reached that urban form can be explored as fractals within certain ranges of scales and fractal geometry can be applied to the spatial analysis of the scale-free aspects of urban morphology.

The Solutions to the Uncertainty Problem of Urban Fractal Dimension Calculation

Fractal geometry provides a powerful tool for scale-free spatial analysis of cities, but the fractal dimension calculation results always depend on methods and scopes of the study area. This phenomenon has been puzzling many researchers. This paper is devoted to discussing the problem of uncertainty of fractal dimension estimation and the potential solutions to it. Using regular fractals as archetypes, we can reveal the causes and effects of the diversity of fractal dimension estimation results by analogy. The main factors influencing fractal dimension values of cities include prefractal structure, multi-scaling fractal patterns, and self-affine fractal growth. The solution to the problem is to substitute the real fractal dimension values with comparable fractal dimensions. The main measures are as follows. First, select a proper method for a special fractal study. Second, define a proper study area for a city according to a study aim, or define comparable study areas for different cities. These suggestions may be helpful for the students who take interest in or have already participated in the studies of fractal cities.

The connectivity of Haifa urban open space network

Urban open spaces are considered as spatial residuals of the expansion of built areas. The environmental impact of the resulting land-cover pattern and associated ecosystem services are frequently evaluated at a crude spatial resolution only. However, wild animals use remaining interconnected fine-grain open spaces as an infrastructure for movement.

In this paper, we traced the evolution of an open-space system in Haifa, Israel, and examined the impact of urban morphology on size and distribution of open spaces at different spatial resolutions.

At a 30 m resolution, our analysis indicated fragmentation and increasing partial elimination of open spaces. Over time the connectivity declined at a diminishing rate, yet the network did not disintegrate into separate components. The evolution analysis implied that in crude resolution, the open space network is threatened.

At a 5 m resolution, our analysis showed that Haifa remains porous to animal movement. Using combined multiple least-cost paths through the urban landscape of heterogeneous permeability, we illustrated extensive connectivity among open spaces. Backyards and other urban in-between spaces complemented the seminatural open-space network connectivity, enabling wildlife movement between habitat patches and thus survival in an urbanized environment.

Spatiotemporal Evolution of Urban Form and Land-Use Structure in Hangzhou, China: Evidence from Fractals

Using fractal theory and urban land-use maps for 1949, 1959, 1980, and 1996, this study is devoted to analyzing the evolutionary features of urban form and land-use structure in Hangzhou, China. We find that self-similarity exists in both the built-up area and the municipal area, and fractal properties tend to become better defined with time. The fractal dimension of each type of land use is less than that of all land use. From 1980 to 1996, the fractal dimensions of residential, industrial, and external transport increased while those of educational and virescent land use decreased, indicating that partial degradation accompanied holistic optimization during the process of Hangzhou's self-organizing evolvement. The mechanisms of the spatiotemporal evolution of urban form in Hangzhou are discussed, including socioeconomic development and the dispersal or concentration of activities. The Tandabing approach to urban spatial expansion, the Jianfengchazhen approach to urban construction, and a top-down urban management style led to differences in fractal evolution between Chinese and Western cities.

Residential and Nonresidential Construction Initiations in Tel Aviv-Yafo: Autocorrelation Analysis of Urban Structure Evolution

Construction initiation (CI) of floor area is an important socioeconomic and physical characteristic of urban structure and its evolution. Despite its importance and the availability of CI data, it has not attracted significant attention until now. Since the 1970s, the Tel Aviv-Yafo Municipality and Israel Central Bureau of Statistics have collected annual CI data pertaining to residential and nonresidential categories for subquarters. This paper presents an analysis of the spatial evolution of the city of Tel Aviv in the years 1976–2003, from the CI perspective. Novel aspects of this research are related to autocorrelation analysis CI patterns in individual years versus annually accumulated construction and in core versus noncore build up categories. It is shown that floor-area additions form relatively complex spatiotemporal patterns that are not referred to explicitly in existing urban studies of Tel Aviv. Autocorrelation results suggest the superimposition of current almost homogeneous or random spread over earlier phases of core area domination: the formation of uniform choice space. These random patterns represent primarily spontaneous residential regeneration processes since 1990, and major diffusion of the commercial and public activities beyond the central business district areas.