NEAT PEAT | Anna Rottau | Final review

Rate of deforestation in Indonesia overtakes the Brazil and because of that I have chosen these tropical islands as localization of my project.

Half of Indonesia tree cover is gone. Since last three decades land conversion destroys region biodiversity and natural heritage. Organic, Carbon rich soil, like peat, is degraded as never before. Timber and Palm oil plantations are set without any consideration about the impact of carbon emission. Recently Indonesia became the biggest producer and exporter of palm oil worldwide. Nowadays half of the world palm oil comes from Indonesia and the problem is growing.

Chosen region in central Sumatra, Riau regency is characterized by well documented forest degradation  and very high percentage of oil palm plantation concessions. Most of the area is covered in peat. One of the big plantations is localized on a land with especially big peatland depth.  I have chosen a fraction of plantation with most regular grid in order to let my solution be implemented later on in other localizations. Grid is build by drainage canals, connected to the river and communication infrastructure, connecting it with neighbour Pekanbaru city.

Plantation on a chosen site was established in 2008 and covers peatland of thickness between two and eight meters. In the area there are 30 000 palms planted.

Tropical peat bogs are significant carbon sinks, accumulating tons of carbon through thousand of years. Nowadays the process is reversed and peatlands are emitting the carbon instead of storing it.

Native peatland forest  grows in a nutrient poor, acid and wet soil. It support diverse ecosystems, and is a home to many extincting species. It’s structure and closed canopy gives great conditions for the decomposition of biomass and creation of new layer of peat.

Companies converting forested peatland for palm oil plantations first cut canals to drain the peat, than clear the trees for planting. Most often they are burning the indigenous forest, together with top peat layer. Exposed peat surface oxidises and loses stored carbon rapidly to the atmosphere. It has destruction impact on the amount of atmospheric carbon dioxide concentration. dry peatland is also much more likely to catch fire. Annual carbon losses due to fires are equivalent to about 3000 years of peat accumulation. Once the forest is removed and the peat is drained, small seedlings are set and plantation started. Poor chemical composition of peat requires regular fertilizing the soil and palms itself. Before the canopy closure takes place, for 5 years peat is exposed to sun, subsides and emits Co2.

Because of the amount of oil extracted from fruit bunches, both kernel and pulp, palm oil is called most productive and cheap vegetable oil in the world. Because of that we find it in most food and chemical products in shops.

In the light of Asia turning into cooking on palm oil, increasing amount of people in the world,  it is crucial to plant palms in a sustainable way. Like any agricultural activity, oil palm cultivation can be done well. I have decided to keep the oil palms on a site and find a solution which can bring local people benefits from the new plantations.

Basic idea uses  biomass waste coming from plantation in order to divide the acid peat soil from the palms. If we divide palms requiring dry soil from peat, drainage of land can be stopped. Raised beds made out of palm trunks and leaves are called hugelkultur. These approach enlarges the area of possible use. In my case raised beds create a space for additional crops to be planted in between the palms, following the alley cropping rules.

    Since PEAT has a vital role to play in regulating our climate: My aim is to rewet soil, prevent water from escaping and place housing on a site. I’ve decided to find localization which needs recovery first. I chose driest land with the thickest cover of peat soil.

I have created a map of peat soil thickness, based on existing Lidar data and simulated the ultimate wetness of soil. I have Combined informations given by the rainwater flow, topography map and existing drainage grid. I have translated mapped data into voronoi diagram, in which similar areas  of similar features.

First diagram represents biggest amount of peat as the smallest cells. Second diagram shows the driest, most degraded areas, as the biggest cells.

Combining these two factors enabled me to group cells. The one representing the driest land will be a place of first settlements, from where damping of canals and rewetting will start. In order to protect thickest cover of peat I start up an indigenous forest zones in areas with biggest amount of peat.

I am proposing three steps of inhabiting the land. Green represents returning indigenous forest and pink housing zones (human influenced area). Zones in the time would enlarge, drainage canals will be naturally backfilled by forest. In Between mentioned there is a grey transition zone.

Starting from now, 50 years timeline shows the process of stimulating the biodiversity. Aim of the process is : converting monoculture into permaculture plantation .

Existing palm plantation is being cutted away in 10 years from now, because of the decreased productivity. Raised beds are formed out of palm trunks, leaves and other biomass. Naw palms are planted on the top of them. In Between as in alley cropping other plants are introduced. Pink color represents crops which are part of 3 first permaculture zones, close to housing, while grey transition zone is a mixture of crops,native fruit trees and timber trees. I introduce intercropping of sago palm, to derive flour, climbing bamboo to be used as building material and other shrubs, crops and trees creating diverse food forest. between rows legumes are a source of living mulch. Shifting specific species of different time growth and yield rate allows to have an enclosed canopy and  to keep the peatland in shade. Because of that all development becomes carbon negative, since we store more  inside the ground than release.

    Because of the localization and tropical wet climate, main challenge of housing units would be it’s natural ventilation.

Analyzing the prevailing winds map I have decided to group housing in areas  most exposed to wind, along the canals and existing communication. In the housing zones I introduce potential localizations together with permaculture zones of each unit to keep enough space in between buildings.

I have decided to bringing the Land back to local people by tasseleting big plantation into smaller parcels. In order to do so I used voronoi tessellation as a guidelines and manipulated it. Drainage canals are being blocked by inhabitants in order to establish/set inland fisheries and make place for hydroponics. Peatland is not being drained any more, water flow is stopped. Canals in the zone of indigenous forest are backfilled naturally by decomposing biomass of vegetation falling into water.

By providing constant supervision of the land we ensure that it will not be degraded any more since owners needs ponds. I design units in a way they are independent from the outside infrastructure. On a site there is a commune and public space where are located basic services. In the lowest parts of the site there are constructed wetlands, each purifying the grey water for few houses and releasing pure into the ground, rewetting the peat. For a site of my design I have chosen the driest area needing fastest recovery. Damming of canals start from there.

    Idea for perfect house for tropical humid climate was a house without walls, open as much as possible and interior has to be perfectly shaded.

I wanted to develop different way of shading than local and conventional architecture. I’ve got inspired by trees roots, the way they are  reaching and opening outside. Especially very particular bottress roots existing in the peat swamp forest. Buttress roots are vertically elevating boards. It gave me an idea about basing housing unit using structural boards being at the same time partitions inside the house. Buttress roots are developed on a soft ground and provide stability. They cover specific big section area in order to provide stability to tree. Additionally they expanded envelope surface increase gas exchange which is what we are looking for in our house. Breathing house, shaded by high partitions, with narrow space in between for rooms.  

  Being inspired by biomimicry I developed a grasshopper script enabling me to design each partition curvature separately and the roots planar distribution. I propose a house for two people small and big family. Zoning in between: simple life, open main room, space for guest receiving. Big children rooms. I have examined by radiation analysis the height of a building in order to get the interior totally shaded, which equals 8 meters. Passive cooling. Partitions are big enough to channel the wind. Analysis have shown that stuck effect will be most efficient, more than regular cross ventilation. Predicted openings at the bottom of the envelope and at the top force the air movement.

    Fews starategies: permaculture integrated with fairshare  living, aquaculture; hydroponics  ponds, pisciculture – fishing ponds. Closed cycles: kitchen-ponds, garden-compost in raised beds,  garden-home, carbon stored back in the soil, Treated grey water-released-rainwater catchment. Possible energy: biogas from communal waste

     The structure in the building is a lightweight structure, made out of native material: bamboo, chap, very fast growing, easy to harvest and assemble. Pillars are made out of grouped bamboo members. Each column have an individual footing in a geo-concrete, containing waste from palm oil production. In between there is a porous skin out of woven bamboo slats, dense at the top, loose at the bottom. With main opening at the entrance and smaller one from each room.