2. The possibilites of urban farming
• In case of inner parts of the difficulties are quite similar.
• There are housing estates, brownfields, industrial zones, downtowns,
traffic areas.
• The first problem in general in this case is not the possibility of urban
food production, but the existence of urban green areas.
• On the one hand the greatest problem is the extremley great rate of
artificial surface cover (pavements, rails, buildings). This is a typical
problem of brownfields, industrial areas and downtowns.
• The other great problem is the extremely great size of buildings. This
is typical in case of housing estates and downtowns.
• Downtowns have the greatest disadvantages from the point of view
of urban farming.
• The extreme density of functions means an other great problem
(traffic areas, industrial zones).
6. • In case of housing estates the real problem is the size of the buildings
and the property questions.
• The rate of green surface is (in case of Hungary) relatively high
(around 50%), or at least it can be relaively high.
• On the green surfaces the possibilities of urban farming is the same
that of garden cities.
• The only difference is the property. In case of common owner the
harvest is more difficult. Social organisation, existing communities
and existing community gardening is necessary for viable urban
farming in case of housing estates.
• The buildings, which are usually huge, with at least 10 storeys and
many flats, cover almost the 50% of the total area. Its possible usage
is a great question, which appears also in case of downtowns.
Housing estates IV.
7. • Agriculture is based on crop production till the Agrucultural Revolution (for
10000 years).
• The main crops
Fruit production on public green surfaces I.
8. • Agriculture is based on crop production till the Agrucultural Revolution (for
10000 years).
• The main crops
Fruit production on public green surfaces II.
9. Urban fruit trees (turkish hazelnut)
• Property problems: there are many solutions. The so called
community garden, moreover the hiring (a community hires a garden,
or an inner yard; an urban farmer hires an allee from the local
government, or simply a band of unpaved property and plant into it
fruit trees etc.). In urban circumstances the stealing is a much smaller
problem, due to the cameras public lights and the permanent
appearance of other unknown people.
• Plant protection is a great problem: Current chemicals are not
suitable. There are two possible solution: 1. developing new
chemicals (needs a lot of money and time and the success is not
sure); 2 choosing such selected fruit tree types which do not require
chemicals, highly resistant for insects and fungus (already exist such
selected fruit tree types).
10. • In case of greater buildings (higher than 10 metres) there are many
problems from the point of view of traditional food production and
also greening.
• In case of smaller buildings, the usage of greater trees and rambling
plants can be very effectively provideing the necessary green for the
dwellers.
• As it was mentioned previously, the appropriate trees and climbing
plants make possible the food production on the these ways.
• In case of greater buildings lianas can not reach higher storeys. To be
able to effectively use up the surfaces (roof and facades) of the
building, different kind of green roofs must be applied.
• Using green roofs the question of water supply is extremely
important. In case of food production the appropriate nutrition must
be also solved.
The problems of greater buildings.
11. • Considering the necessity of green roofs, there are many kind of
them, but their main purpose is recreation (rooftop gardens), or heat
insulation (extensive green roof).
• Besides these main features they have a lot of advantages, like
positive effects on urban climate, increased building structure
lifetime, increasing spaces for urban ecosystems, water retain/rainfall
buffer.
• The usage and effects are very similar to ordinary urban green areas,
although the conditions for plants are less friendly.
• Considering the food production aim, the ordinary extensive green
roof (without irrrigation, using only succulent plants and mosses) can
not be appropriate.
• Similarly to traditional extensive and intensive food production areas,
in most cases the irrigation is necessary.
• Irrigation must be sustainable.
Green roofs on greater buildings
12. Extensive green roofs
• In case of extensive green roofs the role of the vegetation is only the
stablizitation of the surface of the soil/growing medium.
• The positive effects are rather due to the soil layer, than the
vegetation, not suitable for urban farming.
13. Intensive green roofs
• In case of intensive green roofs the soil layer is much thicker (at least
40-50 cm as against by the extensive green roofs 5-15 cm), and the
irrigation is provided.
• The main purpose is recreation.
14. • In Hungary the main difference between extensive and intensive
green roofs is the possibility of permanent irrigation.
• Considering the question in global, the main difference must be the
thickness of the soil layer. If the soil layer is thick enough, then there
is the possibility to planting trees and shrubs onto the roof.
• The necessity of irrigation is basically a question of climate. In case of
Hungary, these green surfaces requires irrigation. Considering
oceanic, tropical, monsoon, rainforest climates irrigation is
neglectible.
• In case of desert and semi-desert and mefiterranean climate types
irrigation is necessary.
• In case of nediterranean-type climates there can be some exceptions
in case of food production.
Green roofs and climate
15. Intensive green roof on semi-desert climate
• A church in Salt Lake City. Covered by intensive gren roof, which need
almost permanent irrigation.
• Unsustainable solution.
16. Intensive green roof on oceanic climate
• An intensive green roof in Manhattan. Oceanic climate, rain occur in
every season, irrigation is neglectable.
• Sustainable solution.
17. • In case of traditional agriculture: In ordinary case agriculture do NOT
require irrigation!!!
• Among every climate circumstances there were already found and
selected the most appropriate plants for food production (wheat for
mediterranean, rice for monsoon climate).
• The so called intensive agriculture produce such goods, which can not
be considered as basic food (vegetables, fruit).
• Moreover, these plants can be easily cultivated in smaller gardens,
only in case of greater plantations cause the production an
environmental problem.
• In case of green roofs the thickness of soil layer is important (to do
not hurt the building structure by the cultivating machines).
• Moreover, in certain cases, where irrigation is necessary, water can
be provided on sustainable way.
Irrigation and sustainability
18. Wheat
• Agriculture is based on crop production till the Agrucultural Revolution (for
10000 years).
• The main crops
19. Rice
• Agriculture is based on crop production till the Agrucultural Revolution (for
10000 years).
• The main crops
20. • In case of thick (40-50 cm) soil layer wheat can be effectively
cultivated without irrigation on mediterranean-type climates.
• In case of thick (40-50 cm) soil layer rice can be effectively cultivated
without additional irrigation on monsoon-type climates.
• Nutrition is an other important factor.
• First question is the soil: in present day green roofs the quality of soil
is quite bad from the point of view of food production, because the
main purpose is not the product, but to keep up without earthwork
the structure of the soil.
• Thus, traditional, good quality soil must be put onte green roofs adn
below ot must be taken a good drainage soil type layer.
• The question of nutritions: the situation is similar to traditional
agriculture, the nutrition must be taken up to the roof. The nutritions
can be chemical or traditional manure. Organic farming is the real
solution instead of using herbicid, fungicid and pesticid chemicals.
Irrigation and sustainability
21. • Water management in case of such greater buildings is the most
important.
• It consists of two greater parts: the first is the rainwater
management, while the second is the so called „grey water”
management.
• Rainwater management can be solved on the simplest way by the
appropriate building construction.
• The scheme is the following: the roof of such a multi storeyed
building is flat, and covered by a green roof, with 40-50 cm thick soil
layer, and wheat or rice is cultivated in it.
• The greatest amount of rain will be used up by the rice or wheat. The
minor (but still momentous) part will be collected in water reservoirs
under the roof. This can be used for irrigating plants which can be
planted on thin belting green roofs around the building on the
appropriate levels/storeys. These can be used for fruit, or vegetable
production. This water can be also used up inside flats in bathrooms.
Water management I.
22. • Grey water management: using up the appropriate waste water .
• Grey water= wastewater, which does not contain human manure.
• Grey water can be excellently used up for irrigating green roofs, or
green walls.
• If it does not contain poisonous materials (and this can be awaited),
then it can be used up for irrigating plants of food production.
• There exist already excellent examples (Bosco Verticale, Milano) for
using up grey water for irrigating green walls, altough these green
walls was made not for food production.
• The corellation with the previously mentioned rainwater
management is strong, because rainwater can be used up also in
bathrooms, while greywater can be used up for plant irrigation.
• The appropriate construction is essential to be able to provide the
necessary circumstances for effective urban farming.
Water management II.
27. • Green roofs, even extensive green roofs are much heavier than any
other roof.
• In case of urban farming, the necessary thick soil layer means an even
greater weight.
• Thus the building construction must be stronger.
• On the one hand this means, that the initial cost of a building is
higher.
• The greater problem is the existing housing estates. For example in
Hungary most of them can not be maintained with any kind of green
roof, because their structural qualities.
• This means that urban farming is possible rather in case of new
buildings.
• Even in case of stronger existing buildings the necessary changes has
much more cost, than by creating a new building, where these
features are already involved into the design.
Static/structural problems.
28. • In case of greater buildings fungus farming is always a viable way.
• Moreover aquaponics and hyroponics is also viable.
• There must be mentioned the so called blue roofs.
• In case of existing blue roofs (i.e. Oasis 21 in Nagoya) the main goal
was climate modification.
• Nevertheless providing a water ecosystem with rainwater can be
ideal for aquaponics.
• There exists also the possibility of using rainwater (if the quality is
appropriate) for hydroponics.
• The great advantage of blue roofs and the usage of water ecosystems
and hydroponics that the specific weight of water is only about the
thid of soil. Moreover a thinner layer of water is enough for this
purpose.
• Using glasshouses on the flat roofs, make the water usage optimal
and provides the control of the quality and quantity of water.
Further opportunities.
32. • In case of traffic zones urban farming is not possible directly.
• There can be created pavements both for vehicles and pedestrians,
which can produce energy (by containing solar panels, or rather
piezoelectric units).
• The urban water management system has to deal with the rainwater,
which is collected in the traffic areas. On the one hand, these
surfaces can not be water covered, on the other hand this water must
be collected and cleaned to be able to use up for irrigating urban
green areas.
• In case of brownfields the revitalization is the most important. Among
the existing stage the natural appearing ruderal plants can have
momentous effect on the local climate and ecology.
• Brownfields usually consist of traffic zones and greater buildings, thus
these can be treated separately similarly to housing estates and
traffic zones.
• The question of downtown is similar to that of housing estates,
excepting the rate of green area is much smaller.
Further opportunities.
