CAIRO: By hook or by crook, Egyptians always manage to slither out of adversity. Who would have thought that the greenery we lack in the heart of the stifling, dusty city, would flourish on the rooftops of some of its most destitute areas. Once again Cairo proves that nature always finds a way.
Traditionally, Egyptian rooftops were no more than a depository of all manner of things ranging from satellite dishes, unwanted furniture, a sink here and a ladder there.
Enter the growing trend of Green Roof Agriculture (GRA), also known as urban agriculture or soil-less agriculture, a technology which will help confront the long term threats of global warming, smog, pollution and the urban heat island (UHI) effect.
According to wikipedia.org, UHIs are metropolitan areas which are significantly warmer than their surrounding rural areas. The temperature differences are most apparent when winds are weak, with the main cause being the modification of the land surface by urban development. Waste heat generated by energy usage is a secondary contributor.
By decreasing the temperature of a building, green rooftops can also lower their air-conditioning requirements.
Residents of over-populated and underprivileged areas like Dar El-Salam, Bab El-Shaeriya, Shubra, Saft El-Laban, some parts of Moqattam and Bolaq El-Daqrour have taken on this challenge with the double-edged benefit of cooling down their buildings and complementing their incomes with rooftop gardens, producing everything from cucumbers, tomatoes and lettuce, to spinach and even strawberries.
The soil used for GRA consists of unlikely ingredients such as sawdust, hay, coconut fibers, and treated sand or volcanic rocks heated at specific temperatures, says agriculture professor Osama El-Beheiry, head of the Arid Land Agricultural Research Institute (ALARI) at Ain Shams University, the body which has officially adopted this method since its inception.
A “soil-less method, he explains, creates an alternative atmosphere for plants.
Since GRA was introduced to Egypt in 1999 by the United Nations’ Food and Agriculture Organization, between 5,000-6,000 square meters of roof areas have been greened, according to El-Beheiry.
“Although this may seem insignificant it is a promising beginning that is bound to expand through ALARI’s efforts and awareness campaigns, he says.
Initially GRA methods targeted arid and equatorial zones where impoverished communities were deprived of eating fresh green vegetables due to the less arable nature of their land.
In Egypt the technology developed from using old car tires or traditional clay pots for cultivation, to using various semi-intensive systems that include the table and container method as well as the hanged bags, the A-shape, wall and aeroponic facilities, all of which can be operated using manual or automatic irrigation and fertilization, explained El-Beheiry.
“At the beginning it was difficult to convince people of the usefulness of this new approach, so we decided to spread the word at schools. Although the Ministry of Education was initially reluctant to consider the issue, some of the officials got a little more excited when they were updated on results.
This was a breakthrough for ALARI considering the huge number of students who can be reached through public schools.
“The Cairo governor ordered GRA to be introduced to 206 schools in Cairo, said El-Beheiry. “We are currently working on launching a program at 30 schools covering the various educational zones in the capital.
During a visit to one of ALARI’s green rooftops, professor Sayed Hassan, agriculture expert at the institute, said that GRA is the only hope for Egypt to become a major exporter of agricultural products.
“International markets now stipulate certain standards for the food products they import, Hassan told Daily News Egypt. “One of these is a ban on methyl bromide, a chemical used to cleanse the soil which was revealed to be a major carcinogenic.
“GRA is one of the few options left to produce chemical and pollutants-free fruits and vegetables, said Hassan.
While Omaima Sawan, the head of the Agricultural Department at the National Research Center in Cairo (NRC), recommends the technology for arid zones and home agriculture, Ismail El-Bagouri, expert at the Desert Research Center (DRC), remains skeptical about major aspects of the technology.
“I am all for this technology provided that home growers are informed by experts on issues related to extra weight on buildings and the harmful effect of the water on the premises, says El-Bagouri.
“As for its use on a grand scale to replace the traditional soil, he added, “I doubt its feasibility because the food products and plants that constitute a significant part of our exports are so plenty and diverse, and so we can’t do without using traditional soil.
“I suggest we try to focus on research to find alternatives for methyl bromide and other harmful chemicals, he continued.
Ahmed El-Tanahi of the National Research Center, however, disagrees. “We can’t look at it that way, he says. “If we compare the cost of cultivation per square meter using the traditional and soil-less methods we will find that the latter method is both more feasible and cost-effective. If this is the only option left, then why shouldn’t we experiment with it?
For more information on rooftop agriculture, contact ARALI at (02) 4444-1386.