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Working Group 1A - Comparison of Case Studies |
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Case study Oslo -
Draft 1. ©Signe Nyhuus,
Department for Environmental Affairs and Transport,
Municipality og Oslo, 2002 Introduction The municipality of Oslo
(454 km2) is located in the inner part of the Oslo Fjord in
South Eastern Norway (59'55 N, 10'45 E). Approximately 2/3
(307 km2) of the municipality is covered by forest,
waterways and agricultural land and 1/3 (147 km2) by a
building zone that includes residential, commercial and
industrial areas. Approximately 30 km2 or about 20% of the
building zone is covered by mixed boreal forest and
deciduous trees. The municipality employs approximately 42
000 people and consists of around 70 different agencies.
Since 1995 Oslo has been the fastest growing city of the
Nordic countries with the creation of 69.000 places of work
and an imigration of 46.000 people to the city (the figures
escribes the periode 1995-2000). Compared to its
surroundings the local climate in the city is dominated by
relatively warm summers, low precipitation and mild winters
with the city itself located in a south-facing valley. The
terrain slopes gently upwards from sea to the forested hills
around the city (300-700 meters above sea level). The inner
Oslo Fjord belongs to the Oslo region. Cambro-Silurian
limestone and shales, rich in calcium, folded in the
Caledonian era, make up the central parts of the city and
westwards along the fjord. The Oslo region is a result of an
extended depression of earth covered by sea and slowly
filled with sediments. The age of the rocks varies from
Cambrian to Permian (600-250 million year ago). Remnants of
the Pre-Cambrian rock, mainly of gneiss and granite, are
exposed in the southern and eastern part the municipality
(Dons 1996, Holtedahl and Dons 1957). 1. How have natural
and cultural factors influenced the development of
greenstructure in the urban environment? New archaeological
findings date the city back to year 1000 and for that reason
Oslo celebrated its 1000 anniversary in the year of 2000.
Back then the natural landscape was strongly influenced by
the outlets of 9 rivers in a distance of just some few
kilometres in the inner part of the Oslo fjord. The river
basin was relatively flat covered by lush deciduous
vegetation and the biodiversity must have been very high. On
three sides the landscape rose up to 300-700 meters and
vegetation shifting to coniferous forest, spruce in the
north and west and pine in the east and south. Since the
river basin soil was so rich due to marine sediments there
were many small farms both inside and around the town. This
had some influence on the natural landscape and vegetation
and so had the monisteries that were settled in the town and
on one of the islands in the inner part of the fiord. Many
species were introduced to the excisting flora and some of
them still remains here today even as red listed
species. The town was first
located around the outlet of the Alna river and consisted
merely of wooden houses. The streets were narrow and the
fires were many. In 1624 one of the worst fires in the
history took place. After that King Christian the 4th
decided to move the city to Akershus'back yard both in order
to protect it from the attackers and to construct a new city
built of stone. From there the city expanded to the size it
has today. Figure 1 shows the development of the urban
sprawl in Oslo for the last two centuries. The natural
vegetation in and around the city was slowely transfered to
gardens and cultivated parks and the last two centuries
rivers have been canalised underground. Today approximately
60 % of the 283 kilometres of water corridors are canalised
underground. Most of the urban
development has taken place after the second world war. The
social democratic government in charge right after the end
of the war had one slogan: Urban and rural hand in hand.
This was an efficient methode of looking at the country as a
hole. For the farmers it ment among other things that they
had to leave a lot of agricultural land near the biggest
cities to new towns. Some of the suburban areas in Oslo are
built on some of the best agricultural land in the country
(Groruddalen, Bøler). However soil protection became
an important issue during the sixties and seventies and so
the suburban areas from the seventies are built on bedrock
(Romsås, Søndre Nordstrand). The built up area of
Oslo is still one of Europe's least densely populated and
the rate of development today is, according to some
politicians, not high enough in order to meet the rising
demand for housing. The pressure on the greenstructure
within the built-up area is however strong due to the
preservation of the forested area surrounding the building
zone but lying within the municipal border. The region
areound the municipality of Oslo consists of about 6-7
municipalities. Most of these are more liberal concerning
development on virgin land because they want to keep the
countryside character as a contrast to the city. The
consequence of this politics is however that recreational
areas in the neighbour communities dissapear. A large part of the
population of Oslo are used to live in green surroundings
and the awareness of the greeenstructure being threatened
has just been wakened the last 20 years. An analysis of the
reduction of greenstructure in Oslo from 1952-1990 revealed
a significant impact on three categories of greenstructure
due to land use changes from natural areas to residential,
commercial and industrial space (Guttu et al. 1997). The
same study found that there has been a strong fragmentation
of areas, on average a 50 % reduction from 1950-1990, which
resulted in more, but smaller areas of green open spaces.
The same trend could be anticipated to take place from 1990
to the present day, but the introduction of the Green Plan
(Oslo Municipality 1993) and the Green Chart (Oslo
Municipality 1997) are actions that hopefully alter this
development. A comparative study of
several European cities (Oslo, Stockholm, Copenhagen,
Helsinki, den Haag, Bristol, Birmingham, Hannover, Gdansk,
Zaragosa) carried out by the University of Oslo on the
inquiry from the Municipalty, shows that Oslo was largest in
area, but had only 27 % of the area developed. The rest was
forests and greenstructure The separation between
the forest and development area has been on the agenda for
many years. Politicians decided many decades ago that all
new development should take place within a border between
the forested area and the area that was defined as the
built-up area. This border has stayed the same since then
even though new politicians now and then have suggested to
built on virgin land (Marka) outside the border. Figure 2
shows a map of the municipality showing the situation. The
vegetation/forest type and the management in Marka differ
very much from the vegetation types and management within
the built-up area. However both types are
multifunctional. Along with the reduction
of greenstructure follows higher pressure on remaining
areas. Wear and tear increases as well as the need for more
detailed and skilled management. Oslo has become a
multicultural city during the last 20 years. Today different
cultures use the green open spaces differently but the local
knowledge is so far too low in order to develop a management
system that includes these aspects. Another feature of the
planning procedure in Oslo is a high degree of private
planning where private initiatives develop zoning plans for
approval by the Building and Planning Authority where a lack
of biodiversity information may unknowingly lead to loss of
natural vegetation and habitat fragmentation. Being
multifunctional greenstructure demands a multi professional
planning strategy and management. 2. What does this
greenstructure mean for biodiversity, environmental sevices
and management of flows? Table 1 shows different
land use and greenspace categories within the build-up area
of the municipality. The
category forest in the table means a mix between pine and
decidous trees, Ulmus glabra
being the most common followed by Tilia cordata and Pinus
sylvestris. Biodiversity: Due to a mild local
climate, calcium-rich soil, varied topography and a short
gradient between sea level and the surrounding boreal
forests, the city of Oslo is very rich in biodiversity in
relation to its location and latitude. The different
naturetypes recorded in the municipality is shown in figure
x. The richest biotopes of natural vegetation are on the
Cambro-Silurian layers up to approximately 220 meters above
sea level. Furthermore, Oslo has an international
responsibility for these biotopes due to the very
specialised vegetation (rich broad-leaved deciduous forest,
calcaerous woodland and calcaerous rocky shores), species
richness and the high number of red-listed species. This
vegetation is uniquely found in the building zone and on the
islands and the need for preservation and in some cases
management becomes even more urgent since these vegetation
types are not found in the forested areas outside the
building zone. Biodiversity in Oslo is
located in the forest (Marka), within the greenstructure of
the built up area, in the building zone in general and in
and around sweet and salt water. Figure x shows the main
distribution of the overall habitat types in the
municipality. Most of the biodiversity is found in these and
other habitats and only some very few species (birds) are
dependent on the urban construction itself. Two main
features of the greenstructure is highly important: the size
of the open spaces and the quality and management of them.
Figure 1. The share of
some main habitat categories in the municipality of
Oslo. Figure 2. The recorded
habitats in Oslo are classified according to national
High/Low Importance classification criterias. The diagramme
shows that the different importance classes contain about
the same share of habitats. Environmental
services: For recreational
purposes Oslo provides good access to green open spaces for
people to use within the built up area. European Common
Indiactor number 4 asks for access to green areas within 300
meters from the recidence. 95% has access when considering
all areas regardless of size while 89% has access to an area
larger than 10000m2 within 300 meters from their residence.
So far the indicator does not regard the quality of the
green open spaces that are accessable. The information has
been handed over to the City Districts and it is up to them
to analyse their greenstructure in detail. 10 Districts have
elaborated a Green Chart which is a very useful
tool. The report "Ecological
land use principles for the built up area of Oslo 1991"
explores a network of small green areas that fuction as
noise reducing and/or pollution reducing elements in the
city. Some of these still excist and some have been
developed during the densification periode of the ninties.
Oslo is still a very green city but there is now a rising
awareness of the functions of these small open spaces.
Schools and kindergardens have started to adopt "100 yard
woods" in their neighbourhood. In order to get
the Figure 3. Map showing
green areas within the building zone available for people
300 meters from the house they live in. Environmental
certificate "Environmental Lighthouse" (an official
Norwegian environmental certification for small and medium
sized private and public businesses) one of the demands is
to adopt such an area in their pedagogical system and
practical teaching. Several analysis
concerning air quality and corridors for ventilation have
been carried out during the last 15 years. Stations
monitoring air quality and pollution are located on
strategic places according to the results of these analysis.
Limited studies in inner city districts with low
environmental qualities has resulted in replacing a
kindergarden when stagnation of low quality air was
identyfied. Despite that, in large development projects
decisions have been taken in opposition to recommendations
with bad consequences for local air quality. For Oslo this
is especially bad because of the natural landscape features.
During winter days with high pressure and no wind air will
stagnate in the "pot-shaped" landscape. The increasing focus
on possibilities to re-open parts of the rivers and brooks
running through the urban landscape could lead to a better
flow also for winds in the city. Management of
flows: 60% of the rivers
running through Oslo are canalised underground. When the
last city government came in office they had two main
environmental tasks on the agenda. One was to strengthen
public transportation, the other was to restore the
blue-greenstructure of the city. About 10 years ago the
biggest river in Oslo, Akerselva, was focused on. A land use
plan including management principles were elaborated and
some actions were taken. This work has altered Akerselva
from a grey river to a salom river containing sweet water
insects and bottom animals that are returning to the
ecosystem. Today the second biggest river Alna is
prioritized. Both Alna and Akerselva have been strongly
influenced by industry and thus pollution. The industries
have however moved out of the city or ceased to exist and
the housing development has taken over as the main the
pressure on the remaining green river banks. Also two other
rivers, Ljanselva and Lysakerelva, are in good shape
containing several fish species while two others are in a
rather bad shape. During the 90ties Oslo
has experienced floodings especially in Akerselva. This has
had both environmental and economic consequences since it is
running through the most developed and urban part of the
city and has illustrated for the management system how
valuable green riverbanks are in order to handle the water
load. 3. How are the
ecological and environmental functions of greenstructure
considered in landuse/landscape planning? How are the
functions been managed to meet ecological and environmental
goals? Land use and landscape
planning is carried out both according to formal and
juridically binding planning instrumenst and according to
more informal tools that have been elaborated in order to
meet some of the ecological or "green" challenges. I will
therefore describe them separatly in: B. Informal
strategies A.The formal
instruments regarded as most important is the Master Plan,
the Green Plan and the White Paper for Urban
Ecology. Master Plan: The overall strategy of
the municipality concerning the shortage of housing is
densification of existing central residential areas in
connection with the public transport network.Oslos Master
Plan has during the last twenty years developed from a
detailed land use plan to a more stategic plan. It points
out areas suitable for densification, as for today being
collective junctions, and gives point of directions of types
of development. Although there is less greenstructure in
central urban areas the existing green open spaces here are
often prone to loss and fragmentation. The strategy is
explained through four categories elaborated for
densification planning purposes. These are: The last category
includes the largest area and the freedom of the developers
is extended compared to the first three
categories Ecological aspects
from the White Paper for Environment is also included as
background information for the Masterplan. Green
Plan: This is a municipal plan
for the greenstructure. Only parts of the greenstructure is
juridically binding according to the plan. The rest is
recommendations. It was adopted in 1993 and has since then
been followed up the the Recreational Office. The plan is
especially strong on defining missing links in the overall
path/corridor system that links green areas togheter. Some
areas have even been acquired though todays political
strategies are looking for land and properties to sell
rather than to buy. White Paper for Urban
Ecology: This is the strategic
plan for the environmental sector and has status as a white
paper because it is adopted first in the city government and
finally in the city parliament. It includes strategic
guidance for the blue-greenstructure and biodiversity. It is
revised every fourth year and the latest one will be adopted
in the fall of 2002. It guides the different municipal
agencies to what is prioritized politics the next four year
periode and is also a signal to the public since it is
published on internet. Forest Management
Plan: The plan lines up
priciples for the management of the urban forest
sourrounding Oslo. The forest as a hole does not belong to
the greenstructure, but the edge of about 1000meter is
usually included in the greenstructure of the city. It was
adopted in 1996 and is multifuctional with a main focus on
recreational aspects. Also ecological considerations is
regarded as more important than the economic aspects of
timber. B.Oslo has several
more or less informal instruments in order to manage the
green structure. The most important are: Green
Poster Both the Green plan and
the Master plan are meant for a higher level than the detail
planning level. One of the results generated from research
was a planning method for a so-called Green poster or Green
chart. This is meant to be a professional tool serving as a
"green warning signal" for planners and contractors. Based
on several part studies of recreational, -landscape and
biodiversity data the Green Poster is a synthesis and a
strong recommendation highlighting the crucial green
structure. The poster shows in other words which areas one
should preserve and/or develop in order to take care of the
different needs and functions connected to the green
structure. It also identifies the need for recreation
corridors and wildlife corridors. The results are presented
on a single map designed as something like a poster which is
to be placed in many relevant offices, therefore the name
Green poster. During the long lasting Norwegian programme
Environmentally Friendly Cities coordinated by the Minitry
of Environment (1993-2000) the five participating cities
developed the Green Poster and Oslo was the first to make
on. Also several other cities have elaborated it, some as a
point of departure for the legally binding Green Plan,
others as a professional tool with no status other than
serving as basic knowledge. In Oslo today the Poster is used
by the Health and Nutrition Authorty as a fundament for
evaluating detail plans. The reason for this is that
according to the law this authority receives absolutly all
detail plans. If they are in conflicts with the Green
Poster, the plans are sent back to the Planning and Building
Authority with remarks and for a new opinion. Today the
Poster needs to be revised and information feeded into a
data base system like the one used for biodiversity in order
to get good statistics and a more professional design of the
Poster. District Recreation
Maps. Though being useful for
an overall planning level the Green Poster turned out not
too useful for a detailed planning level. The demand for
even more detailed information became urgent. A pilot
project was carried out together with one chosen City
district. The focus was especially on how different groups
of citizens used the green open spaces. An open space on a
map does not show the physical qualities of the area and
what kind of activities that it is suitable for. In this
project it was therefore necessary to carry out fieldwork.
Master students executed this with a geographer as a project
leader and a reference group consisting of persons from
different parts of the municipal management system following
the project. The first map was finished in 1999 and so far
10 city districts have elaborated such maps. The maps are
not only useful in detailed physical planning but also in
connection with Local Agenda 21 processes. In Oslo the city
districts play a major role in the work for Local Agenda 21.
Each district has a LA21 coordinator. It is today 25
districts but the desicion to reduce the number of has been
agreed upon in the city council. 4. How is ecology
being implemented? Biodiversity The strong pressure on
urban and suburban areas in Oslo due to shortage of housing
has introduced an urgent need for a tool ensuring that all
decision-makers in physical planning have relevant
biological information accessible at an early stage in the
planning process. Also a political decision at the national
level encourages all municipalities to survey and classify
their biodiversity according to a scale of importance within
2003. The city of Oslo has just recorded the important
habitats for biodiversity within the greenstructure in the
build up area. The number of species in different groups
recorded so far is shown in figure 2, 3 and 4. A small
number of red listed plant species grow on wasteland,
pavements etc. Except for these species the greenstructure
is housing a major part of the biodiversity found in
Oslo. Tools to effectively
apply biological information in daily physical planning
cases are viewed as essential in order to preserve and
manage natural habitats in highly pressured urban areas. A
GIS based management tool for conservation and management of
biodiversity and the process of implementation is therefore
prioritized and elaborated. The main objective of this
multi-agency effort is to ensure a sustainable and
responsible management of the biodiversity within the
municipality. The electronic tool elaborated makes it
possible to combine biological information with any other
information that is relevant for a planning issue. The
system enables the local authority to early detect any
conflicts between conservation interests and other types of
land use as well as serving as an information system for the
public and consultants dealing with environmental impact
assessments. The management tool comprises the entire
municipality including forested and agricultural land
outside the urban and suburban area. The Municipality has
also bought an area from a private developer in order to
save a pond housing "stor salmander". This was an ongoing
discussion in the media and pupils close to the pond finally
adopted the pond and thus got a lot of attention from the
media. The conflict was unnecessary since the information
was available but not known in the planning and building
office. The new system will hopefully prevent such conflicts
to happen in the future. Blue-greenstructure Since the City
government has focused on the rivers of Oslo and thereby the
green open areas along the rivers a committee was formed
called "River forum" consisting of members from the relevant
agencies in the municipality, relevant NGO's and relevant
state agencies. Strategies and new routines for planning and
management of the rivers and their adjacent open areas are
being developed. New developments and
buildings New developments that
the municipality is responsible for demands an environmental
plan concidering outdoor areas, flows and building
materials. This is of importance for the local grenstructure
and the small open spaces. The Public Housing Bank has also
elaborated demands about out-door qualities and the bank
rewards developments and private houses that take care of
trees and other natural qualities on the
property. 5. What is currently
recorded about greenspace ecology? One of the greatest
challenges of greenspace ecology and other sustainable
issues today is partly more data but most of all
communicating the results and importance to the citizens.
The tendency is that such issues drown in the information
flow and the press will not convey environmental issues
unless there are conflicts connected to them. That is one of
the reasons for the participation in EEA`s project Cities
Environmental report on Internet (CEROI). CEROI is an
international methode that allows sustainable themes to be
published on internet. Many european cities are working with
the first edition. It is especially important in order to
inform the public and start a dialog on the state of art and
the different steps taken on sustainable issues. In Oslo,17
themes important for sustainability are described following
the so called DPSIR methodology (D=driving forces,
P=pressure, S=state, I=impacts, R=respons). Among these
themes are greenstructure, biodiversity and water. The
internet report also includes the 10 European Sustainable
Indicators. One of these is access to green open spaces and
is referred to earlier in this paper. Norway has adopted a
national Environmental Certification called the
Environmental Lighthouse for small and medium size
businesses and public offices. This is especially designed
for businesses that will not undergo an EMAS or ISO 14001
certification. Demands are elaborated for each type of
businesses. For instance schools and kindergarten have
special demands that must be fulfilled before they get the
certificate. One of the demands are to adopt a green open
space and use this in the teaching. The city of Oslo has
decided to adopte the Environmental Lighthouse. 14
kindergartens have achieved the certificate and the first
group of schools are just about to start. We therefore
expect an increased awareness of the role that these areas
play in the greenstructure the coming years.
A. Formal
planning instruments
Working
Group 1A -
Comparison of Case Studies Other papers
relating to people/ ecology interface Sheffield to
do
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updated Juky 2003