Tuesday, November 3, 2009

A Biointensive Approach to Urban Agriculture

The Bio-intensive method
It is an organic agricultural system which focuses on maximum yields from the minimum area of land, while si
multaneously improving the soil. The goal of the method is long term sustainability on a closed system basis. It has also been used successfully on small scale commercial farms (1). Whole farming systems give emphasis to diversity and offer both a sufficient amount and quality food which generates profit to buy other provisions. It further provides the family with a year-round supply of food and income together with a year-round source of employment.

The System

  • In order to achieve greater productivity, the bio-intensive method uses double dug raised beds, intensive planting, and companion planting.
  • In double digging, a 12 inch (305 mm) deep trench is dug across the width of the bed with a flat spade, and the soil from that first trench is set aside. The 12 inches (305 mm) below the trench are loosened with a spading fork.
  • When the next trench is dug, that soil is dropped into the empty space of the first trench, and the lower layer is again loosened with a spading fork. This process is repeated along the full length of the bed. The final trench is filled with the soil that was removed from the first trench. The result is a bed that has been tilled to a depth of 24 inches (610 mm).
  • When an entire bed has been double dug, the soil will have greater drainage and aeration, which allows the roots to grow much deeper and reach more nutrients. Despite the fact that no soil has been added, the bed is raised due to the aeration.
  • Unworked soil should be double dug each season until the soil has attained good structure and long lasting aeration. During subsequent seasons, it can be single dug with a spading fork until compaction again becomes apparent. After double digging the first season, deep tilling during subsequent seasons can be quickly accomplished with a u-bar, particularly in the cases of larger mini farms or commercial farms (1).

The bio intensive method includes the raising of animals. A diet which incorporates animal products can be raised bio intensively, without graze. Although this uses the land less efficiently than a vegan diet raised bio intensively, it is more space efficient than typical methods of raising animals(1).

Factors Contributing To the Need for Urban Agriculture
Since the world population is increasing urban quarters have turned out to be an essential new leading edge for food production. The city expansion and degradation contribute towards the crucial need for urban agricultural development. The economic and health problems resulting from malnutrition have caused great concern amongst planners and decision-makers. A case study of an Ethiopian urban agriculture consultant, Yilma Getachew, argues that “…organic agriculture is a valid strategy for both stimulating economic growth and developing markets…” and that he could verify this by his experience in supporting urban agriculture in three towns in Ethiopia. “Families in one town keep dairy cows either to supplement their meager salaries, or are totally dependent on milk and dung sales as their sole source of family income. In the other two towns, the main income source is the production of Irish potatoes and sweet potatoes together with a small amount of assorted vegetables not only selling to local markets but also to markets within a 200 kilometer radius. In this way, organic agriculture in an urban setting can both be a tool for community building (health and vitality) and development (income generation and marketing of scarce nutritious food).”(2) (1) http://en.wikipedia.org/wiki/Biointensive
(2) http://www.ruaf.org/sites/default/files/The%20Living%20Garden.pdf

Water Supply Problem & Solution

In Guatemala City, Guatemala

One of Guatemala's most alarming issues is the lack of access by all of its residents to a clean, safe water supply.Like other developing country cities, Guatemala City grew very quickly during the 1980s. Its population almost doubled in under 40 years, from 477,000 in 1955 to 946,000 in 1995, and the metropolitan region is even larger, comprising approximately 3 million people.
A large portion of the residents live in precarious and illegal squatter settlements. These have grown up because there is not enough housing for all the new arrivals to the city in the legal neighbourhoods. The residents of the squatter settlements have no legal rights to the land, pay no taxes, and receive no city services. Their homes are without water or toilets. Most residents obtain their water from a few public taps or from privately owned water trucks. Water purchased from these trucks is often contaminated. Because they do not own their own homes, most residents cannot obtain credit to invest in improving housing standards and infrastructure.
Because of poor living conditions, including the lack of clean water and the consumption of contaminated water, people in these settlements suffer many health problems. Prime among them is the high incidence of often fatal diarrhoeal diseases. A 1990 study found that the prevalence of acute diarrhoeal diseases and acute respiratory infections in precarious settlements was more than twice as high as in the rest of the city. Infant mortality rates, which increased by 10% between 1979 and 1984, exceed 64 per thousand live births and can reach as high as 130 in many of these settlements. Many residents are not aware of the relationship between their living conditions and health problems.
After an outbreak of typhoid fever, residents of El Mezquital, a squatter settlement of 9400 families in Guatemala City, got help from the United Nations Children's Fund (UNICEF) to support the installation of an emergency water supply system.Working with the French organisation, Medecins sans Frontieres (Doctors Without Borders), and with a community association, UNICEF purchased and helped distribute the construction materials for 13 community water taps, which were installed by local volunteers.

Soon after the pipes were laid in El Mezquital, a change in city government provided the opportunity for a more broad-based effort to address similar problems in other settlements. UNICEF, in co-operation with a local organisation called COINAP (Committee for the Attention to the Population of Precarious Areas in Guatemala City) started working with communities to help identify the best ways to provide water to the residents. Community volunteers were trained to conduct surveys to determine the extent of the health problems. Next they met with the COINAP technical team to discuss the volunteers' ideas about possible solutions. Volunteers were also taught how and why diarrhoea occurs and how to prevent children from being infected. As the community members learned more about the health impacts, they became strongly motivated to help improve their living conditions.

Two different models for improved water supply were developed: the single-source tank and the well. Both required active community involvement, outside technical help, and the institutional support of COINAP.

In Chinautla (one neighbourhood of Guatemala City), residents asked the city to install the single-source water tank. Such units are usually installed only on a temporary basis at construction sites. From this single source, the community created a supply network to reach individual residences. UNICEF provided the funds for the pipes and other materials, and each family provided its own home connection. The local community association receives the bill from the water company, and it collects payment from residents for the water they have used. A resident chosen by the community from residents is set aside for maintenance, and any surplus will go toward other local infrastructure needs such as drains and sewers. Although the cost of the water is more than the cost of households connected to the city water system, it is still far less than the exorbitant rates the private trucks had charged.

Saturday, October 31, 2009

Shelter & Water Supply

Derinkuyu Underground City

Being the largest excavated underground city in Turkey, Derinkuyu is one of many of its kind. It is located in the region of Cappadocia and the first level was built by the Phrygians in the 8th–7th centuries B.C according to the Turkish Department of Culture,[2] the underground city at Derinkuyu was enlarged in the Byzantine era. The city could be closed from inside with large stone doors. With storerooms and wells that made long stays possible, the city had air shafts which are up to 100 feet (30 m) deep. The complex has a total 11 floors, though many floors have not been excavated. Each floor could be closed off separately.
The city was connected with other underground cities through miles of tunnels.
The city could accommodate between 3,000 and 50,000 people.

It was opened for visitors as of 1969 and to date, only ten percent of the underground city is accessible for tourists.

Its eight floors extend at a depth of approximately 85m.

The underground city at Derinkuyu has all the usual amenities found in other underground complexes across Cappadocia, such as wine and oil presses, stables, cellars, storage rooms, refectories, and chapels. Unique to the Derinkuyu complex and located on the second floor is a spacious room with a barrel vaulted ceiling. It has been reported that this room was used as a religious school and the rooms to the left were studies[1].

Between the third and fourth levels is a vertical staircase. This passage way leads to a cruciform church on the lowest level.

The large 55 m ventilation shaft appears to have been used as a well. The shaft also provided water to both the villagers above and, if the outside world was not accessible, to those in hiding.

The underground city of Derinkuyu was the hiding place for the first Christians who were escaping from the persecution of the Roman empire[4].[citation needed] Everything discovered in these underground settlements belongs to the Middle Byzantine Period, between the 5th and the 10th centuries A.D. The number of underground settlements, generally used for taking refuge and for religious purposes, increased during this era. The Christian communities in the region took refuge, closing the millstone doors, when they were subjected to Arab raids which started in the 7th century. The raiders, aware of the dangers awaiting them inside, tried to make the local people leave their shelters by poisoning their wells.