ON AFFORESTATION AND SLOPES
AN URBAN DESIGN INVESTIGATION ON MAPUTO, MOZAMBIQUE
Laura Ysenbaardt
On Afforestation and Slopes
An urban design investigation on Maputo, Mozambique Laura Ysenbaardt
Eindwerk aangeboden tot het verkrijgen van het diploma Master in de Ingenieurswetenschappen: Architectuur promotor: Bruno De Meulder co-promotor: Wim Wambecq Local promotor: JosĂŠ Forjaz
Academiejaar 2013 - 2014
Master in de Ingenieurswetenschappen: Architectuur
KU Leuven Faculteit Ingenieurswetenschappen
2013-2014
Master’s thesis file
Student : Laura Ysenbaardt
Title: On Afforestation and Slopes. An Urban Design Investigation on Maputo, Mozambique.
Abstract : Throughout history Maputo has, even after the independence in 1975, coherently inscribed itself in a highly undulating relief. The Ponta Vermelha formation, a north-south oriented central sand ridge with an asymmetric slope, represents the topographical center of the city. From East to West the landscape rises and falls from the mangrove forests of the Incomati estuary, over the erosive steep eastern flank of the sand ridge and the gentle west flank with local wet depression, to the Infulene valley. The safe high places of the city quickly lead to formal consolidation, while still expanding informal tissue inscribed itself in erosive slopes and floodable lower places. The eastern escarpment of the centrally situated sand ridge forms the division between higher and lower city, between formal and informal tissue. Increasing population density in (especially) informal urban tissue in combination with periods of heavy rainfall lead to severe landslides with gully erosion as a result. These gullies, that mediate between higher and lower city, form the focus area of this fourth book on afforestation and slopes. How will the erosion define the relation between high and low? Also, how can we deal with this specific problem that includes the relation between urbanization and nature? Can we re-integrate the sand ridge as a system in which the gullies define new public spaces that overcome the disturbed relation between higher and lower city?
Thesis submitted to obtain the degree of Master in Engineering: Architecture
Promotor : Bruno De Meulder Co-promotor : Wim Wambecq Local promotor : JosĂŠ Forjaz
Permission for Use of Content: “The authors herewith permit that the present dissertation be made available for consultation; parts of it may be copied, strictly for personal use. Every other use is subject to strict copyright reservations. Particular reference is made to the obligation of explicitly mentioning the source when quoting the present dissertation’s rules.” Leuven, 2013 All images presented in this booklet are, unless credits are given, made or drawn by the authors.
Copyright KU Leuven “Without written permission of the promotors and the authors it is forbidden to reproduce or adapt in any form or by any means any part of this publication. Requests for obtaining the right to reproduce or utilize parts of this publication should be addressed to dept. Architecture, Kasteelpark Arenberg 1/2431, B-3001 Leuven, +32-16-321361 or via e-mail to secretariaat@asro.kuleuven.be. A written permission of the promotor is also required to use the methods, products, schematics and programs described in this work for industrial or commercial use, and for submitting this publication in scientific contests.”
Acknowledgements I would like to express my gratitude to the people who made the outcome of this thesis possible, to JosĂŠ Forjaz, local promotor, for introducing us to the complex urban reality that characterizes Maputo today, and for making himself and his considerable knowledge available whenever we showed up on his doorstep unannounced. to Bruno De Meulder, promotor, for his constructive comments and his ability to conceptualize complex issues during our many meetings. to Wim Wambecq, co-promotor, for his critical insights in the field of landscape urbanism and his compelling enthusiasm. His inexhaustible energy truly inspired us to push our limits. to Srini, our host and first friend upon arriving in Maputo, for giving us our own place to come home to after a long day in the field. His sincere interest in the cultures of the world were inspirational and will stay with us forever. to everyone at the Faculdade de Arquitectura e Planeamento FĂsico of Eduardo Mondlane University, in particular Luis Lage, for sharing his considerable experience in Mozambican urbanism and addressing his personal network to get us in contact with experts on certain matters. to VLIR, ASRO, and OSA, for the institutional and financial support that made our stay in Maputo possible. to my family, friends and boyfriend for their sincere interest and motivating encouragements. to my parents for the moral support and all the given opportunities. And finally I would also like to thank Nico, my fellow companion and the other half of Studio Maputo, for the past year full of shared joy and late-night movie nights during our deadlines.
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Acknowledgements 9 Preface 12
I Prologue 15 Urban tissue 24 Extreme rainfall 28
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Framing the site 36 Social forestry in the outskirts of Maputo 42 Trees as structural elements on the slope Cultivation and densification of the urban tissue
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Trees as structural elements in the floodplain Mangrove rehabilitation and productive agroforestry
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Trees as structural elements on the sand ridge Rethinking the chapa station and Xiquelene market
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Aftermath 79
Bibliography
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Preface Throughout history Maputo has, even after the independence in 1975, coherently inscribed itself in a highly undulating relief. The Ponta Vermelha formation, a north-south oriented central sand ridge with an asymmetric slope, represents the topographical center of the city. From east to west the landscape rises and falls from the mangrove forests of the Incomati estuary, over the erosive steep eastern flank of the sand ridge and the gentle west flank with local wet depression, to the Infulene valley. The safe high places of the city quickly lead to formal consolidation, while still expanding informal tissue inscribed itself in erosive slopes and floodable lower places. The eastern escarpment of the centrally situated sand ridge forms the division between higher and lower city, between formal and informal tissue. Increasing population density in (especially) informal urban tissue in combination with periods of heavy rainfall lead to severe landslides with gully erosion as a result. These gullies mediate between higher & lower city and form the focus area of this fourth book on afforestation and slopes. How will the erosion define the relation between high and low? Also, how can we deal with this specific problem that includes the relation between urbanization and nature? Can we re-integrate the sand ridge as a system in which the gullies define new public spaces that overcome the disturbed relation between higher and lower city?
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Right: Maputo (Lourenรงo Marques) seen from the Ponta Vermelha sand ridge towards the lower city or Baixa where the first Portuguese settlements were situated, 1881.
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PROLOGUE
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The fourth and last book in this series about Maputo gives a deeper insight in our vision for the future of the city based on specific geographical characteristics in relation to topography, geology and forestry, as already stated in the second leaflet. The steep eastern hillside will be the focus area for specific design interventions that demonstrate how can be dealt with the relation between higher and lower city and how vegetation can be structural for the city’s future expansion.Whereas before the civil war and accompanying influx of people to the city the relation between urbanization on top of the sand ridge and nature in the low lying floodplain was clearly demarcated by this steep slope, the relation between these two is now disturbed. The soil movement induced by heavy rains in February 2000 will be the starting point of the interventions. High and low are almost literally connected throughout this movement. The higher city loses soil, while the low city gains this same soil. The chart on the next page indicates the slope gradients of the terrain. The Ponta Vermelha sand ridge can be clearly distinguished as a centrally situated landscape element in the city.
Left: Eastern escarpment of the Ponta Vermelha formation in the city center, 1906. Next page: slope gradients of the Ponta Vermelha formation, PDU 1969.
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URBAN TISSUE ON THE SLOPE Throughout history the eastern escarpment that marks the boundary between high city and the low-lying floodplain has always been a strong structuring element in the city’s development. Several infrastructures like the railway, roads coming from the cement city and public transport routes are adapted to this shifting topography. The railway starts in the Baixa, deflects as it approaches the escarpment and runs parallel to it further north. It is along this railway on top of the sand ridge that numerous groups of people started to settle from the 1960’s on, mainly for its favourable geographical position. Also, the main roads on top of the sand ridge run parallel to it and cross the slope only two times to make the connection with the Avenida Marginal along the Costa do Sol. When after the independence from Portugal the civil war broke out, the land use pressure increased exponentially. Whereas before the slope was a demarcated border, it was conquered after 1975 by people looking for a safer place to live in the capital. This land use pressure expands in the direction of the floodplain where more and more informal settlements start to occur and severely affect the pristine fragile ecosystems. This spontaneous and disorganized settlements on the slope show clear marks of erosion due to a lack of basic facilities such as controlled water drainage and supply. Above all they are highly susceptible to natural disasters because of the terrain’s topography. The next page gives an impression of the living environment of the informal settlements ‘on the edge’.
One of the main roads coming from the city center
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Right: sketch of the eastern hillside as structural element in the urban landscape. Next page: Impressions from the dense urban tissue situated on the slope.
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EXTREME RAINFALL Maputo is highly vulnerable to natural disasters mainly due to its geographical position. High precipitation variability, atmospheric instability, situated in the preferred path of tropical cyclones and at the estuary of several major international rivers are the most important factors that contribute to the prone position towards natural disasters of Mozambique [Ruby et al., 2008]. In February 2000 Maputo city was afflicted by a series of extreme rainfall that caused severe flooding in the entire city as well as erosion problems on the eastern hillside. In only four days 400mm rain was registered due to a tropical cyclone that remained stationary before the Mozambican coast for a rather long time. An enormous amount of water the city was not prepared for as the average monthly precipitation for February is only 124 mm. The rains raised the water tables in the city and saturated the soil which resulted in landslides and gully erosion. The situation was worst in bairros Polana Caniço A and B where the slope is most dense occupied with informal settlements. The gullies cut straight through the urban tissue with a depth varying between 1 and 15 meters and steep sides up to 60° but locally steeper [Vicente, 2011]. Several houses collapsed leaving hundreds of families homeless forcing them to relocate further north. Ever since this extreme rainfall basic stabilizing works have been carried out preventing the gullies from further erosion. However, the storm in february 2000 was not an isolated event. In January 2013 a new storm hit the Mozambican coast, aggravating the erosion problems along the eastern hillside. In less than 24 hours 157mm of rain fell, 80 people died and almost 200.000 people were forced to relocate [Unicef, 2013]. The graphic on the right page shows the maximum daily rainfall in Maputo between 1907 and 2000. In 2000 a maximum of 328mm on a single day was recorded. The following chapter proposes several design strategies that try to overcome the demarcated distinction between gully and its surrounding urban tissue on the slope,on the sand ridge and in the floodplain.
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Right: Woman wading through the streets in the cement city after a storm, 2012. Graphic: Maximum daily rainfall in Maputo between 1907 and 2000, cfr. booklet 1 p.26. Next pages: Gully erosion problems in bairros Polana Caniço A and B, 2013.
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DESIGN STRATEGIES
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FRAMING THE SITE The design intervention site is situated on the slope of the eastern escarpment at the border between bairro Polana Caniço A and Ferroviario. During the floods of 2000 a major landslide occurred at the height of Xiquelene market and the chapa station. This vibrant market and regional public transport stop are situated on the crossing of two main paved roads. Avenida Forças Populares de Liberação de Moçambique, coming from the west, is a large four lane highway marked by a larger scale industrial tissue that eventually blends into a dirt road and becomes the gully on the slope. Avenida Julius Nyerere, coming from the south, originates on top of the sand ridge in the cement city and runs parallel to it further north.This road was severely affected by the heavy rains of 2000 as well, a section of approximately 2km collapsed due to saturation of the soil and was swept away by the water, leaving a gap of almost 30m. Rehabilitation works are currently being carried to reconstruct the road in its original condition. However, additional measures should be taken in order to prevent the road from collapsing again during the next extreme rainfall event. The eastern escarpment has always been a strong structural element in the city, not only the main roads run parallel to it but also the railway, who comes from the Baixa in the cement city, deflects as it approaches the escarpment. The escarpment as a structural element is also visible in the urban tissue that surrounds ‘gully Xiquelene’. Formal settlements are situated on top of the sand ridge organized by the government in a large street grid. In contrast to the settlements in the transition zone between high and low (the slope) and the floodplain where informal settlements arise in an disorganized spontaneous way.
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Xiquelene market Chapa station Industry along the Av. das Forças Pop. Lib. de Moçambique
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Right: Topography and urban structural elements on the design intervention site. Left: sketch of the urban structures on the site.
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Left: Xiquelene market. Right: construction material industry along the Av. das Forças Populares de Liberação de Moçambique. Next page: Stairs constructed to acces the gully at the height of Xiquelene market and the chapa station.
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SOCIAL FORESTRY IN THE OUTSKIRTS OF MAPUTO Soil movement as starting point for a design strategy on the eastern escarpment
The following design strategies along ‘gully Xiquelene’ show the potential of the gullies as a system along the entire eastern hillside. The movement of the soil induced by the floods of February 2000 will be the starting point for new developments with aforrestation patterns as structural element whereby the relation between high and low urban tissue will be altered. The imprint of the gully Xiquelene in the eastern hillside cuts straight through informal tissue situated on the slope making the connection between urbanisation on top of the sand ridge and nature in the valley. Most of Maputo’s citizens living in the sub- and peri-urban areas depend on charcoal and fuelwood for their cooking which is nowadays, due to a lack of forests in the proximity of Maputo, imported from Chokwe or Chicualacuala on the Zimbabwean border, almost 550 km from Maputo. These logging activities are illegal and a threat to the still existing forests in the northern provinces. Maputo lacks a working afforestation program that can reduce the import of wood from the northern provinces. Providing the people with fuelwood in their own backyard could be a large step to restoring the forest cover in around Maputo as a self renewing reference. [Studio Maputo booklet 1 p.32, 2014] In this respect, an afforestation program that deals with this wood scarcity and at the same time overcomes the disturbed relation between high and low is proposed along this gully. Three different forest matrices are laid out, differing in size due to the necessary plant spacing of the tree species that are used. Matrix 1 is situated on top of the sand ridge and is implemented parallel to the escarpment. A single trees specie, Chanfuta (Afzelia Quanzensis), is used to accentuate the geographical position. Chanfuta is an indigenous tree specie that is sought-after for its good grain and resistance to pests. Therefore it is mainly used in the furniture industry and as construction material. The second forest matrix is implemented perpendicular to the slope and makes the transition between high and low. A combination of two omnipresent tree species are used, Mango (Mangifera Indica) and Cashew (Anacardium Occidentale). Both species have a large spreading crown for shade and provide an extra food resource. A third matrix will be implemented on the small ‘embankment’ in the floodplain formed by the millenium floods and will be further explored in the following interventions. To accentuate the gully as a strong landscape element, only grasses that are slightly differing in height are used in combination with the characteristic Red Acacia (Delonix Regia), that has given Maputo the name ‘city of fire trees’. The following design strategies demonstrate how these forest matrices can act as structural elements and induce transformations in the urban tissue while at the same time laying the foundation for a more sustainable development of the city based on the idea of afforestation and slopes.
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Forest matrix 1
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Grasses in gully and 3th forest matrix
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TREES AS STRUCTURAL ELEMENTS ON THE SLOPE Cultivation and densification of the urban tissue The first focus area is situated where forest matrices 1 & 2 overlap and gives a deeper insight in the implementation of the trees and gully as a strong landscape figure on the slope. To accentuate the gully as an independent strong figure that cuts through the informal tissue, the vegetation used to stabilize the sides of the gully and prevent the surrounding urban tissue from further erosion is a combination of three types of grasses. These grasses are ranging in height between 5 and 150cm. From low to high, Bermudagrass (Cynodon Dactylon), Giant star grass (Cynodon plectostachyus) and Vetiver (Chrysopogon Nigritanus). Vetiver is a fast growing grass specie that is frequently used to reduce and stabilize erodible ground, particularly steep slopes. The plants roots grow, in contrast to other grass species, vertical instead of horizontal and can become 2 to 4m long. Besides preventing erosion, Vetiver also improves the soil quality and can thus be considered a nurse plant for other species. Also, the leaves have several medicinal features and are commonly used for basket weaving. Therefore a community center is implemented along the gully in the proximity of the school and can be used as a gathering space for women where they can participate in e.g. basket weaving workshops. The red acacia (Delonix Regia), with its bright red flowers that gives Maputo city its characteristic appearance, is used as an accent tree in the gully. The wide dense canopy of this middle sized tree casts full shade and is therefore frequently used as a resting spot in tropical areas. At some places in the urban tissue several trees were logged to create places with more direct sunlight, the ‘clearings’ in the forest. These clearings are also marked with Delonix Regia to accentuate the change in forest cover. A possible scenario is that densification will occur in the urban tissue surrounding this open spaces. The next pages show the chronological implementation of the trees and clearings in the urban tissue. 1. School 2. Community center
Coconut Chanfuta Mango Cashew Red Acacia Bermuda grass (low) Giant star grass (medium) Vetiver (high) Densification
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Implementation of the forest matrices in the urban tissue
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Implementation of the grasses and ‘clearings’ in the forest
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Afzelia Quanzensis (Chanfiuta)
Anacardium Occidentale (Cashew)
Giant star grass (Cynodon plectostachyus)
A detailed ecological section through the gully demonstrates the interplay between the different heights of the vegetation.
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Magnifera Indica (Mango)
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Bermudagrass (Cynodon Dactylon)
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TREES AS STRUCTURAL ELEMENTS IN THE FLOODPLAIN Mangrove rehabilitation and productive agroforestry The second focus area along gully Xiquelene is situated in the floodplain. The soil that was washed away during the floods of 2000 formed a small embankment at the base of the escarpment. The purpose is to implement an ecological landscape on this small scale embankment from approximately 190 x 215m that consists of temporal and permanent vegetation patches combined with a mangrove nursery. The mangrove nursery provides a place where fruits, collected from mangrove plants, are sown and raised to young plants until they are ready to be planted. With the rapid and ongoing expansion of the city and accompanying increase in land use pressure the mangrove areas closest to Maputo city are suffering most under this population growth. Between 1958 en 1991 almost 85% of the mangrove along the Costa do Sol got lost. An ecological disaster whereas mangrove is an important intertidal ecosystem. Moreover, mangrove forests are known to be an excellent nesting and nursery spot, a habitat for water based wildlife, they improve water quality and protect the shore from erosion caused by flooding events [de Boer et al]. To restore the mangrove forest cover in its pristine condition this mangrove nursery is part of a larger scale rehabilitation program that is implemented at the Costa do Sol along the Indian Ocean as seen on pages 36 and 37 of this chapter. 1. 2. 3. 4.
Mangrove nursery Training center Crop fields with kenaf / soybeans rotation Agroforestry project with Moringa, Marula and Coconut trees.
Moringa Coconut Marula Red Acacia Wetland Crops
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In a first phase Moringa Oleifera trees will be planted on the platform in an orthogonal matrix from 6x6m to stabilize the existing embankment and form the basis for the construction of the mangrove nursery and shifting cultivation patches. The choice for an orthogonal matrix is based on the rectangular agricultural plots further north in the valley. In this way the valley can be cultivated in a more efficient and sustainable way and can form the foundation for new urban functions in the future. Besides a high nutrient value, the Moringa tree also fertilizes the soil and is commonly used in tree-planting projects because of its rapid shade cover and its resistance to poor soil conditions. In this respect, the Moringa tree can be considered a nurse crop for slower-growing species. In a second phase the forest matrix is extended to stabilize the accumulated soil due to further erosion of the gully and several Moringa trees have been replaced for two new native species, Marula (Sclerocarya Birrea) and Coconut tree (Cocos Nucifera).
Growth rate : 3-4 m/year (in first year) Use : Food, wood, medicine, erosion control and water purification Origin : Introduced
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Implementation timeline
Cocos Nucifera (Coconut tree)
Growth rate : 1,5 m/year Use : Food, wood Origin : Native
Growth rate : 50cm/year Use : Food, wood, coastal stabilization, windbreak Origin : Native
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In a third phase a few larger clearings are made in the permanent forest that will later be planted with crops in a shifting rotation. The permanent and temporal patches are designed according to the alley-cropping system. Alley cropping is an agroforestry practice where field crops are planted between widely spaced trees or woody plants. This diversification has multiple benefits for the farmers, it improves soil health while at the same time preventing erosion and making the farmers less vulnerable to market fluctuations or crop failures [USDA,2012]. Hibiscus Cannabinus or Kenaf is a fibre crop that is often used in the crop rotation of a legume. Soybeans and kenaf have proven to be compatible. One of the main advantages of a shifting cultivation system is the nitrogen fixation which keeps the soil more fertile for the next crop [Webber III et al, 2002]. In the final phase the mangrove nursery will
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be constructed. Avicennia Marina or grey mangrove will be used in the nursery and the rehabilitation program as this specie has been proven to have a high survival rate when raised in nurseries for restoration. The nursery consists of 12 nursery beds that can grow 9000 seedlings at the same time or 750 per bed. Six salt-water reservoirs with a capacity of 5000l each inundate the nursery beds twice a day through a pumping system [Clarke et al, 2002]. This productive valley creates a small-scale economy that can provide the community with extra food, jobs and resources which makes them less independent of the imported resources from South Africa and the job availability in the cement city.
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Rehabilitation cycle
Growing seeds in nursery
Planting the sprouts in the rehabilitation area
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Crop rotation cycle Avicennia Marina Planting
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TREES AS STRUCTURAL ELEMENTS ON THE SAND RIDGE Rethinking the Chapa station and Xiquelene market The third and final focus area is situated where the ‘soft’ gully, coming from the east, transforms into its hard equivalent along the Avenida Forças Populares de Liberação de Moçambique. The connection between these two is nowadays a large roundabout that only seems to be there to secure the entrance to the chapa station. Only two of the four directions of the crossing are actually working as the Av. J. Nyerere, going south, transforms into a gully as well. This design intervention rethinks the existing traffic situation by eliminating the roundabout and focusing on the main driving directions and the connection of the gully with the industrial urban tissue along Av. das Forças Pop. Lib. de Moçambique. A new typology that aligns with the existing industrial tissue will be implemented in the form of sheds from several dimensions. The large shed connects the industrial tissue on both sides of the road and can host a function working on a larger scale like a wood market or furniture and construction material industry. The Chanfuta tree in the matrix is sought-after for good grain and pest resistance and can be processed in new industrial function. The chapa station is located in the extension of the large shed parallel to one of the main roads. In this way the chapas can drive through the station and continue their way. Due to the repositioning of the station, the public transport route to bairro Ferroviario is slightly altered. The road going to northeast is downgraded to a secondary road only for local traffic and public transport. The typology of the sheds reappears in the strategy for the market where the existing dense cluster of small iron roofs made place for an open market adapted to the size of the settlements on the slope. Smaller sheds and trees alternate and together they form one big ‘roof ’. This open market connects both literally and metaphorically with the productive ecological landscape on the embankment as the market is a direct outlet for the vegetables and fruits grown in the floodplain. The next pages show the initial and new traffic situation as well as the transformation of the urban structure. 1. Wood market 2. Chapa station 3. Open market with smaller sheds
Chanfuta Mango Cashew Red Acacia
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Left: Existing traffic situation. Right: New traffic situation.
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AFTERMATH
III
The previous chapter proposed several design interventions along gully Xiquelene as a pars pro toto for the entire eastern hillside. As already described in booklet 2 (A new vision for the city’s development) these interventions fit in a larger vision of afforestation strategies for the entire city. A social forestry program on the slope and rehabilitation program in the low-lying floodplain use vegetation as structural elements for further urban developments. Despite the fact that Maputo is a rather green city, vegetation is often badly maintained especially in the city center. The design proposals try to raise the awareness of the ecological value and numerous advantages of (healthy) trees in the urban environment. They provide the inhabitants with extra resources and are critical elements in protecting Maputo from the consequences of the climate change and natural disasters. A mangrove and dune forest rehabilitation program, as proposed along the Costa do Sol, can strongly reduce coastal erosion and form a buffer against the sea level rise. The mangrove nursery, as proposed in the previous chapter, can be extended to the other gullies. In this way, five nurseries nurseries with a capacity of 9000 seedlings each are needed to replant the entire mangrove area (approximately 1 km2) along the Costa do Sol in about 22 years. After this period the amount of nurseries can be reduced and transformed into either an urban function or a part of the productive valley. Also, the dune forests that make the transition between the Indian Ocean and the floodplain, play an important role in the protection of the coast. The chart on the right demonstrates the possible inland expansion of a part of the dune forest that partly occupies the current race track, the mangrove rehabilitation area and agricultural activities in the floodplain. Besides the restoration of fragile ecosystems, the railway on that runs parallel to the sand ridge can form a structural element in the city as well. New stops could be implemented and so encourage development around them. The railway could be the key factor in dealing with the current traffic congestion by promoting it as an fast and cheap transport to reach the cement city. Together, these design proposals try to guide to city into a sustainable future development based on the idea of afforestation and slopes.
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BIBLIOGRAPHY Academic Articles CANHANGA S., DIAS J.M., Tidal characteristics of Maputo Bay, Journal of Marine systems 58 (2005) 83-97, 2005 CEDH, UEM, Mozambique, Cities Without Slums, Analysis of the Situation & Proposal of Intervention Strategies, UN-HABITAT Program, Maputo, 2006 CLARKE A., JOHNS L., Mangrove Nurseries: Construction, Propagation and Planting, Fish Habitat Guideline FHG 004, Queensland Fisheries Service, March 2002 DA SILVA PIMENTEL J., Os Espaços Abertos Públicos da Cidade de Maputo, Universidade de Évora, May 2003 DE BOER W.F., The Rise and Fal of the Mangrove Forests in Maputo Bay, Mozambique, Wetlands Ecology and Management 10: 313-322, 2002 DE LIMA J.L.M.P., P. SINGH V., P. DE LIMA I., The influence of storm movement on water erosion: storm direction and velocity effects, Catena 52 (2003) 39-56, 2002 FORSTER A., Gully erosion: an example from Maputo, Mozambique, British Geological Survey, Keyworth, NG12 5GG, UK, 2003 JENKINS P., City profile Maputo, Cities, Vol. 17, No. 3, pp. 207–218, 2000 JENKINS P., Strengthening Access to Land for Housing for the Poor in Maputo, Mozambique, International Journal of Urban and Regional Research, Volume 25.3, September 2001 JENKINS P., Urban management, urban poverty and urban governance: planning and land management in Maputo, Environment and Urbanization 2000 12: 137, April 2000, Pages 137-152, (http://eau.sagepub.com/content/12/1/137) LUCIO F., Predictability of Extreme Events Associated with the Inter-annual Variability of Rainfall, MANUEL I.R., VICENTE E.M., Maputo, A Geo-environmental Hazard Prone City, Disaster Reduction in Africa ISDR Informs Issue 3, April 2004, Pages 20-22 MIDGLEY S., DEJENE A., MATTICK A., Adaptation to Climate Change in Semi-Arid Environments, Experience and Lessons from Mozambique, FAO, 2012 NAZIM et al., Age and Growth Rate Estimation of Grey Mangrove Avicennia Marina, April 2011 NHANCALE B. et al., Small and medium forest enterprises in Mozambique, Centro Terra Viva and International Institute for Environment and Development, London, UK, 2009 NIELSEN M., Mimesis of the State, From Natural Disaster to Urban Citizenship on the Outskirts of Maputo, Mozambique, Social Analysis ,Volume 54, Issue 3, Winter 2010 NIELSEN M., Inverse Governmentality: The Paradoxical Production of Peri-Urban Planning in Maputo, Mozambique, Critique of Anthropology 31(4), 2011NIELSEN M., Speculative Spaces, Being in Permanent Transit in Maputo, Mozambique, AEGIS, Aarhus University, 2013 86
PIMENTEL J., The Power of Shade - the Green Infratsructure in African Slums, Eclas - The power of landscape, 2012 RAVISHANKAR T., RAMASUBRAMANIAN R., Manual on Mangrove Nursery Raising Techniques, M.S. Swaminathan Research Foundation, Chennai, September 2004 RUBY J., CANHANGA S., COSSA O., Assessment of the Impacts of Climate changes to Sea Level Rise at Costa do Sol Beach in Maputo, Mozambique, United Nations Environment Programme (UNEP), July 2008 SITOE A., SALOMÃO A., WERTZ-KANOUNNIKOFF S., The context of REDD+ in Mozambique, Drivers, agents and institutions, Center for International Forestry Research, 2012 USDA, What is Alley Cropping?, February 2012 SYLVESTER K., Erosion Control in Inner City Maputo: Sustained Livelihood Impact?, Understanding Urban Livelihoods, February 2006 VICENTE E.M., JERMY C.A., SCHREINER H.D., Urban Geology of Maputo, Moçambique, IAEG2006 Paper Number 338, 2006 VICENTE E.M., Aspects of the Engineering Geology of Maputo city, Mozambique, University of KwaZulu-Natal, Durban, March 2011
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Cartographic Material AZEVEDO M., PDULM - Plano Director de Urbanização de LM, Maputo, 1969
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Websites AMEND et al., Moringa Oleifera (http://forest.mtu.edu/pcforestry/resources/studentprojects/moringa.htm) [Last visited 25-05-2014] CHAN E., ELEVITCH C.R., Cocos Nucifera (http://www.agroforestry.net/images/pdfs/Cocos-coconut.pdf) [Last visited 21-05-2014] DLAMINI M.D., Afzelia Quanzensis, (http://www.plantzafrica.com/plantab/afzelquan.htm) [Last visited 23-052014] HYDE et al., Mozambique Flora (http://www.mozambiqueflora.com/) [Last visited 27-05-2014] Marula, (http://www.jacanaent.com/Library/Trees/Marula.htm) [Last visited 21-05-2014] SUTHERLAND J., Moringa Oleifera (http://www.le.ac.uk/engineering/staff/Sutherland/moringa/moringa.htm) [Last visited 25-05-2014] UNICEF, UNICEF seeks neraly US$7 million for tens of thousand of flood victims in Mozambique (http://www. unicef.org/mozambique/humanitarian_response_12269.html) [Last visited 22-05-2014] VETIVER NETWORK INTERNATIONAL, Soil Erosion (http://www.vetiver.org/g/soil_erosion.htm) [Last visited 27-05-2014]
Photo Credits Niet alle rechthebbenden van de gebruikte illustraties konden worden achterhaald. Belanghebbenden wordt verzocht contact op te nemen met dept. ASRO, Kasteelpark Arenberg 1/2431, B-3001 Heverlee, +32-16-321361 of via e-mail naar secretariaat@asro.kuleuven.be. 0. PREFACE p 13 : LOBATO A., Lourenço Marques, Biografia da Cidade, Agência Geral do Ultramar, p. 240, Lisboa, 1970 I. PROLOGUE p 16-17 : Satellite image, retrieved 09-05-2014 (http://maps.yahoo.com) (fair use) P 20 : Source unknown p 22-23 : AZEVEDO M., PDULM - Plano Director de Urbanização de LM, Maputo, 1969 p 26-27 : Images by author p 29 : BARNARD J., Storm in Maputo, (http://www.weather-forecast.com/locations/Maputo/photos/7365) p30 : AFP, A road washed away by torrential rainfalls in Maputo, Mozambique (http://www.abc.net.au/news/201301-26/mozambique-hit-by-floods/4485350)
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p 31 : JOHANNESSEN A., Aug Sep Drainage 058, (https://www.flickr.com/photos/aseroon/5226586648/in/ photostream/) II. ON AFFORESTATION AND SLOPES, DESIGN STRATEGIES p 34-35 : Satellite image, retrieved 12-05-2014 (http://maps.yahoo.com) (fair use) p 38 : ZUG55, Xiquelene market (https://www.flickr.com/photos/zug55/8060792432/) p 39 : Source Unknown p 40-41 : JOHANNESSEN A., Aug Sep Drainage 064, (https://www.flickr.com/photos/aseroon/5225998795/) III. AFTERMATH p 85 : STIJJJN, Maputo from Above, 2005 ( https://www.flickr.com/photos/stttijn/95676893/)
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