Landscape – Great Idea! X-LArch III - Department für Raum ...

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Fig. 4: Nested structure
of an urban area
in transformation
urban landscapes and their transformation should be
based on considering the size of the physical elements
which structure the area of intervention and their topological
relations (inclusion, overlapping, crossing, etc.), the
extension of the relational context of the area (not only in
the visual sense, but also in regard to symbolic, functional,
ecological aspects), the width of impacts on resources
and the sets of observers, or better, landscape users.
As an example, figure 4 shows an urban military area
which is now waiting for land use change: here the
ecological role of the existing vegetation, the connections
with the surrounding urban pattern and the function in the
network of public spaces could be profitably interpreted
and projected in the logic of nested scales. Especially for
urban vegetated areas, the trend toward incorporating
multiple scales into management – in opposition to the
view of green spaces as static and isolated from the urban
matrix– could help managers recognize meso-scales
as being as important as long-term, regional and shortterm,
local scales, introducing so a missing level of tactical
planning that could connect strategic and operational
levels in both time and space (Borgström et al., 2006).
Besides, in Production of space, Lefebvre describes the
city as a space of differences, a field in tension, where
the transitional scale M has the key role of mediator
between the private scale and the global, public one.
The dynamic multiscalarity does not only refer to spatial
issues but also to the absolute number and the density of
users and inhabitants, to their different degrees of sharing
and to their footprint: in this sense, urban designers
might create potential environments, but the effective
environment is created by what people actually do within
that setting (Carmona et al., 2003: 107).
The fact that “contemporary urban society lives in
between, in a state of perennial oscillation in the terms
and limits of the sharing of behaviours, practices and
spaces, of values and images, seems to imply a general
rethinking of the project for the city” which should seek “a
sufficient degree of coherence between the momentary
practices of individuals and groups and the degree of
sharing of spaces that are involved each time” (Secchi,
2006). [Fig.5]
Fractal behaviour of urban landscape
Another feature, somehow related to multiscalarity, is
the fractal behaviour of the urban landscape. The spatial
structure of cities and their genesis through small incremental
changes occurring at large scales, the patterns
and length of town boundaries, the processes of urban
sprawl, have been already explored by fractal analysis.
Here we do not refer only to self-similarity of spatial
patterns at different scales, which can be widely found in
natural forms, but also to an interpretation of the features
of urban landscape as parts of a system “not characterized
by top-down structure, but by a network of agents
working in parallel, reacting to their local environmental
conditions” (Birkeland, 2002: 74).
The characters of repetition, self-reproduction and mutual
reinforcement into urban landscapes, where each level
supports and enhances the effectiveness of the others,
both in a negative and in a positive way, reflect the behaviours
of the communities who created those landscapes
and their level of sustainability [Fig. 6].
Maurice Halbwachs, in the 50’s, pointed out the link between
memory and inhabiting: when some human groups
live for a long time in a place which is modified by their
habits, then their movements and their thoughts will fit
with the set of imagery represented by physical objects
of that landscape (Halbwachs,1987: 136). The potential
of the urban landscape of developing a richness of forms
and symbols, in similar ways but at different scales [Fig.
7] shows the virtuous –or unfortunately vicious– circularity
of the anthropic process of reading and writing signs
on the environment (Turri, 1983).
The rules of fractal, lattice structures, with elements
working in parallel, are especially useful for the design of
a fundamental layer of the urban landscape, that of the
green structure, and could act as an alternative to the
fragmentary planning model which considers every green
Fig 5: Behaviours, density, space sharing in urban landscapes