Integral Role of Urban Agriculture

Growing Locally: The Integral Role of Urban Agriculture in the
Cultivation of Livable Cities and Functioning Ecosystems

Amy M.M.P. Hurley, M.S. Community and Regional Planning
Email: amarmaphurl@gmail.com Blog: http://ammph.blogspot.com/

Introduction

For the first time in human history, the majority of the world’s growing population lives and works in metropolitan areas. Cities and their peripheries are demanding evermore resources to support their diverse and dense populations. Until recently, the negative environmental and socioeconomic externalities of meeting these ever-increasing demands have been treated as more or less of a necessary evil of development and modernization. However, the impacts of this forced acceptance are being felt globally and a new paradigm is beginning to emerge. In the Worldwatch Institute’s State of the World 2007: Our Urban Future, Kai N. Lee explains that, “In cities, the high intensity of human activities leads to problems where individual interests are at odds with the common good. The central task of urban sustainability is effectively managing commons problems in the ecosystems that sustain cities.” Lee explains that cities, however large, are each part of an ecosystem and, thus, must find ways to become resilient and sustainable. In other words, the characteristic lack of ecological accountability where cities are concerned is no longer acceptable. Pressing issues like climate change, resource scarcity, ecosystem degradation and its associated extinctions are demanding attention at local, regional and international levels.

Since agriculture is completely dependent on weather and climate, regional food security can also be added to that list as it could soon be seriously compromised in some areas of the globe. Pretty points out that, “this security is already strained by increased demand and the intensification of resource use by the fast-growing human population and by an increase in per capita consumption of agricultural products” (p.320). Over the next 50 years, the human population is expected to rise to at least 8.6 billion demanding evermore farmland that is no longer available. Thus, as Dickson Despommier explains in his essay entitled TheVertical Farm, “alternative strategies for obtaining an abundant and varied food supply without encroachment into the few remaining functional ecosystems must be seriously entertained” (n.d.). One of these alternatives is urban and peri-urban agriculture.

Urban and peri-urban agriculture are universally applicable towards both the environmental and socioeconomic resilience and adaptability of cities and their populations and yet have not been woven into the policy agenda of many metro areas. In an article entitled Continous Productive Urban Landscapes: urban agriculture as an essential infrastructure, Andre Viljoen and Katrin Bohn explain a few reasons why widespread acceptance has been slow in coming here;

Within the design professions, the reason for this neglect of attention to urban agriculture results partly from the lack of quantified and comparative data for the environmental impact of remote food production. In the case of agriculture the energy used on a farm is relatively small, but once “food miles” and petrochemical and food processing inputs are taken into account, the energy impact becomes much larger. Apart from lack of knowledge about the energy arguments in favour of urban agriculture, at least two other reasons can be found for the lack of support for urban agriculture in mixed-use development. A major reason is that it is seen as producing less financial return from land which could otherwise be commercially developed. Another reason is that there is no understanding of what a city, in which urban agriculture is integrated, would be like to live in. (p.34)

Viljoen and Bohn also explain that, “it is necessary to articulate the reasons for considering urban agriculture as an element of “essential infrastructure” within sustainable cities. Just as we see roads and energy systems as essential, urban agriculture should be considered likewise”. VIljoen and Bohn also point out that urban agriculture unlike many other elements of infrastructure offers a number of ancillary benefits at no or low cost to the city. In addition to reducing the urban heat island effect, environmental benefits of urban agriculture include improved resource and energy efficiency (both within the city itself and the resource and energy inputs saved by decreasing “food miles” for each city’s population), increased soil health and biodiversity and improved water quality. It is also clear that urban agriculture supports density and the livability of cities so that urban and suburban sprawl are no longer treated as inevitabilities as they are today.

In following, dense vibrant and agriculturally productive cities have the potential to protect the few remaining expanses of dense unpopulated wilderness left on the planet. In order to establish the path ahead, the present state of the global food system and the high price of what Jules Pretty calls “enclave thinking” and its current vastly inefficient relationship with urbanization will be discussed. The cost of business as usual will, thus, be explained and shown for what it is - very high indeed. Then, the at once ancient and yet completely innovative methods and forms of urban agriculture and their present and possible embodiments will be discussed using specific examples from the case studies mentioned above. These case examples will show the broad palette of urban agriculture and its many positive externalities when given the support and space in which to flourish.

In his book entitled Agri-Culture (2002) Jules Pretty explains that enclave thinking leads us away from accepting the connectivity of nature and people by suggesting that biodiversity and conservation can be in one place, and productive agricultural activities in another. It presupposes that it is acceptable to cause damage in most social and natural landscapes, by preserved small areas at the edges. In reality, these enclaves will always be under threat at their borders, or “simply be too small to be ecologically or socially viable” (p.13). In the foreword to Worldwatch – Our Urban Future (2007) Jaime Lerner explains why urban policymakers and inhabitants must not subscribe to this way of thinking.

Cities are the refuge of solidarity. They can be the safeguards of the inhumane consequences of the globalization process. They can defend us from extraterritoriality and the lack of identity. On the other hand, the fiercest wars are happening in cities, in their marginalized peripheries, in the clash between wealthy enclaves and deprived ghettos. The heaviest environmental burdens are being generated there too, due to our lack of empathy for present and future generations. And this is exactly why it is in our cities that we can make the most progress toward a more peaceful and balanced planet, so we can look at an urban planet with optimism instead of fear. (p. xxii)

Lerner also explains that the major change will be in function rather than form, “In terms of physical configuration, the cities of the future will not differ significantly from the ones of yesterday and today. What will differentiate the good city will be its capacity for reconciling its residents with nature.”(p.xx). In following with this vision statement, urban agriculture will be at the forefront of this process due to its proven ability to visually and experientially reconnect our urban species to the land we inhabit and the natural processes that sustain life on this fragile planet.

In Urban Agriculture: Vegetable Production in Metropolitan Greater Vancouver District in CanadaM.R. S. Mlozi explains that “the main rationale for promoting urban vegetable production in developing and developed countries are similar albeit with some variations, and they are both economic and social”. Mlozi lists the economic justifications as follows;

• generating employment and income to most urban poor and to some middle class urban dwellers;
• enhancing urban economy by recycling goods and promoting self-reliance through the informal sector;
• saving costs on transportation of vegetables from up-country sources;
• making unused land productive, i.e., vacant, un-built or idle, road side, and pavements.
• He then lists the social advantages as follows;
• improving household food security and consequently nutrition and health;
• producing fresh vegetables;
• promoting technology transfer such as food preservation, cooking, processing;
• enhancing community cooperation and improvement and facilitation of group participation and skills development;
• accessing urban resources, especially to women and low income earners where they can learn skills in production and marketing;
• fostering a sense of achievement and hope;
• contributing towards recreation and conservation, especially in managing open spaces;
• serving as experimental or demonstration plots for other urban dwellers to learn improved methods of crop husbandry;
• stimulating non-governmental organizations and community based organizations involvement in poverty alleviation because earnings from vegetable sales are used to buy other household services and goods. (http://homepage.mac.com/cityfarmer/UAvancouverMlozi.doc)

Although the benefits of urban agriculture seem clear, the process of transforming the perception and function of cities is a complex challenge due in part to the fact as Lerner points out here;

“A city is a collective dream. To build this dream is vital. Without it, there will not be the essential involvement of its inhabitants. Therefore, those responsible for the destinies of the city need to draw scenarios clearly – scenarios that are desired by the majority, capable of motivating the efforts of an entire generation.” (p. xxii)

If urban agricultural projects are incorporated into these scenarios on a large-scale from the beginning, the experiential nature of urban farms, markets and gardens offer immediate results that can help garner support from city populations. Neighborhood pride, community meeting places, economic opportunities and stress relief for participants and fresh high-quality produce to supplement the often unhealthy diets of inner-city residents can serve as the most are just a few of the positive social impacts urban agriculture. These will be explored later with case examples from around the world but first, we must examine the present state of affairs.
Industrial Agriculture & Urbanization: A Misdirected Path

Let us begin as a plant would – at the root of the issue-- which as Luc Mougeout wrote in 1994 is that “…the divorce of agriculture from cities, of food production from urban economies, is very recent in the urban history of humanity. It also has not been universal and is showing signs of weakening both in the North and the South.” This weakening or reconciliation of food production and urbanity will be discussed later. First we must examine the philosophy and rationale both cultural and economic has upheld the terms of the divorce as Mougeout refers to it and the toll that this separation has taken locally, regionally and globally on human and natural systems alike. In Agri-Culture Jules Pretty (2002) succinctly explains the stakes of the game we are currently playing;

We are buying a system of production when we purchase its food. In effect, we eat the view and consume the landscape. Clearly, the more we consume of one thing, the more it is likely to be produced. But if the system of production has negative side effects, and cares not about the resources upon which it relies, then we have taken a path leading, ultimately, to disaster. (p.11)

Despommier describes what effect the current system of production is having and how we are in fact consuming the landscape here; “Farming has re-arranged the landscape in favor of cultivated fields and herds of cattle, and has occurred at the expense of natural ecozones, reducing most of them to fragmented, semi-functional units, while completely eliminating many others” (2007). In concert with ecosystem degradation, massive amounts of waste materials are being created without accountability or reuse. Pretty describes these waste components that are exceedingly harmful to already degraded ecosystems here;

Pesticides, nitrogen and phosphorus nutrients, soil, farm wastes and micro-organisms escape from farms to pollute ground and surface water… Agriculture also contributes to atmospheric pollution and, [thus global warming], through the emissions of four gases: methane from livestock, nitrous oxide from fertilizers, ammonia from livestock wastes and some fertilizers, and carbon dioxide from energy and fossil-fuel consumption and the loss of soil carbon. (p.58)

Pretty also suggests that there is another possibility which consists of making choices that promote systems of agricultural production that “increase the stock of nature” by improving the environment while simultaneously producing food (p.11). Unfortunately, however, he explains that “in many agricultural systems, over-intensive use of the land has resulted in sharp declines in soil organic matter and/or increases in soil erosion, some of which, in turn, threatens the viability of agriculture itself” (p.62). Despommier helps illustrate how acute the situation is globally. He explains here;

As of 2004, approximately 800 million hectares of land [about 38% of the total landmass of the earth] were in use for food production – approximating an area equivalent to Brazil, and allowing for the harvesting of an ample food supply for the majority of a human population approaching 6.3 billion. These land-use estimates include grazing lands (formerly grasslands) for cattle, and represents nearly 85% of all land that can support at least a minimum level of agricultural activity.

In other words, much of the land on earth with agricultural potential is already being farmed or used for grazing purposes. Despommier continues with an explanation of the environmental impact of supporting huge numbers of livestock in areas of land converted from wilderness here;

In addition, farming produces a wide variety of feed grains for many millions of head of cattle and other species of domesticated farm animal. In 2003, nearly 33 million head of cattle were produced in the United States, alone. In order to support this large a scale of agricultural activity, millions of hectares of hardwood forest (temperate and tropical), grasslands, wetlands, estuaries, and to a lesser extent coral reefs have been either eliminated or severely damaged with significant loss of biodiversity and wide-spread disruption of ecosystem functions.

Pretty presents the example one of the most stark examples in the western world of industrial agriculture’s leaching and run-off of nutrients, and the disruption of water ecosystems in this excerpt, “the Gulf of Mexico dead zone, an area of 5,000 to 18,000 square kilometers of sea has received so much nutrient input that all aquatic life has been killed” (p.62). In an article entitled Farmer Power the Key to Green Advance, Michel Pimbert points out that, agrochemical nutrient pollution from industrial agriculture’s wasteful practices has created “dead zones” along the coasts of India and China as well. He also points out that industrial farming damages our planet's life support systems in a number of other ways including being a major contributor to global warming through intensive use of fossil fuels for fertilisers, agrochemicals, production, transport, processing, refrigeration and retailing. Human activity, Pimbert explains, now produces more nitrogen than all natural processes combined and that crop and livestock genetic diversity have been compromised through the spread of industrial monocultures, reducing resilience in the face of climate and many other possible changes.

In Globalization and the Physical Environment, Ho-Won Jeong explains that “when material interests override ecological concerns, short-term economic gains are achieved at the expense of long-term environmental sustainability” (p.12). He also points out the horrific truth that more than 97 percent of old-growth forest that has not had “significant human disturbance altering its content or structure” is already gone (p. 7). This global loss of forest cover is one of the many negative effects of survival agriculture in the poorest areas of the world in which land is over-harvested and overgrazed. Jeong also explains that more than 15 percent of the earth’s land, an area bigger than the United States and Canada combined has already been degraded (p. 50). This degradation is an offshoot of the unsustainable demands and practices of today’s global industrial agriculture system that has directly and regularly facilitated the destruction of vast tracts of forest. Pretty explains how society has managed to justify this occurrence in the wider consciousness here; “ Nature is seen as having boundaries – the edges of parks or protected areas. At the landscape level, this creates difficulties because the whole is always more important than each part, and diversity is an important outcome” ( pp.12-13). Through the mindset and the economic and social forces that shape land use demands, forests such as the well-known example of the Amazon rainforest continue to disappear at a rapid and disastrous rate. The biodiversity that is lost in this process is irretrievable. Pretty presents the shocking example of how another type of wilderness, wetlands, have been treated in the U.S. ;

According to the National Research Council, 47 million hectares of wetlands in the U.S. were drained during the past two centuries, and 85 percent of inland waters are now artificially controlled. This created new farmland… But remove the wetlands, and the many valued services they provide are also lost. They are habitats for biodiversity, capture nutrients that run off fields, provide flood protection, and are important cultural features of the landscape. (p.60)

The consequences of these completely irresponsible and short-sighted crimes against nature are only gradually being realized by the majority of the population. The deleterious environmental effects of both industrial and survival agriculture continue to worsen across the globe as population increases and manmade infrastructure expands. Soil and nutrient erosion on a massive scale is one of the many major consequences and it is one that is of particular importance in any discussion of the future of agriculture. Jeong explains that the staggering projected impacts of soil erosion being brought about by land mismanagement and misuse;

Every year the world loses some 25 billion tons of soil, reducing its ability to produce food. Land degradation and desertification are likely to intensify with the continued growth in population and increasing variations in the climate. If the current trends are left unchecked, arable land is expected to shrink in Africa by two-thirds and in Asia by one-third. (pp.50-51)

More and more people are being born in areas where natural resources are being exhausted and/or siphoned off by corporations and/or governments and sent to other parts of the world. In some parts of the world, this process threatens local economies and in others the survival of entire populations. Pretty explains that as prime farmland becomes less accessible to local populations and ancient land management practices are thrown to the wayside, survival agriculture is becoming the norm as opposed to the exception that it once was. The knowledge of the land that has sustained many generations in places like China, India and Mexico is undervalued to the detriment of the land and the communities who once had communal access to it along with the responsibility to sustain it. This, as Pretty explains here, has led to governments and/or corporations taking control;

In some places the loss of local institutions has led to further natural resource degradation. As local institutions have disappeared, so the state has felt obliged to take responsibility for natural resources, largely because of a mistaken assumption that the resources are mismanaged by local people. This solution is rarely beneficial for environments or for poor people. (p.10)

China shows many examples of this occurrence the impacts of which will be felt long into the future. It is no secret that the popular belief and indeed policy in China treats rural people as second class citizens. The local infrastructure in rural areas in nearly nonexistent and local communist officials are “invariably corrupt, and often abuse their power for personal gain” as Rupert Wingfield-Hayes wrote in a recent BBC News article entitled China’s rural millions left behind .

Wing-field Hayes explains that in the last ten years two things have happened to make the tension between the city and the countryside worse. The first is the movement of between 100 and 150 million Chinese peasants from their villages to the cities in search of work. The second is urban sprawl with China’s booming cities spreading onto land that has been farmland for countless generations. Wing-field Hayes points out that a total of 16 million acres (6,475,000 hectares) have fallen prey to development in the last 20 years. This is possible in part due to the fact that in China, agricultural land is owned communally. Wing-field-Hayes explains:

In theory, each village owns the land that surrounds it and each family holds its bit of land on a long term lease. Farmland used to be almost worthless. But as China’s cities expand it is now in high demand… People see their land being taken from them and then turned into $1 million dollar homes… without fundamental change in the way China works, its 700 million peasant farmers will remain second class citizens.

So, presently the tens of millions of former farmers who have moved to the cities are treated as second-class citizens there as well and the option to return to their village to farm is slowly being pulled out of their reach. This has very serious socioeconomic implications for this generation and many to come since it is presently almost impossible for people born in rural China to become full urban residents. This means that they are often denied access to basic necessities such as urban housing and urban schooling for their children. The only work available to them is in factories or construction sites which has a cruel irony all its own.

There are similar changes to what is going on in China going on around the world at present. As prime farmland suddenly becomes prime real estate in many both developing and developed countries, there been an increasing disconnectedness world-wide of people and the natural resources and processes that sustain us all. In Postcards from the the Global Food System #3, Zaid Hassan explains the breadth and significance of these worldwide changes;

The destruction of rural culture needs to be seen for what it is, that is, a serious loss of capacity. The shift from rural to urban, as it’s currently proceeding, signifies a loss of food producing capacity that means more and more people (who once knew how to produce food) are becoming increasingly dependent on industrial agriculture, with its myriad problems, for their food. It represents a steady homogenization of the many farming cultures developed over the centuries in response to local conditions. Skills and knowledge built up over generations are being lost almost overnight. It means that communities as well as the global food system are both becoming less resilient to shock and to change. (2005)

Thus, it is increasingly the case that the poorest inhabitants of the world are left with even less ability support their families than in the past. As rapid cultural changes devalue rural culture and hyper valuate rural land (for development purposes), economic forces extend their antennae further and further into the countryside.

In Free Trade Doesn’t Help Agriculture, Anaradha Mittal, explains how much the American landscape has also changed in less than a century. Mittal points out that in the 1930s, 25% of the U.S. population lived on the nation’s 6 million farms and today America has only 2 million farms that are home to less than 2% of the population. Mittal cites the U.S. Department of Labor projection that the largest job loss among all occupations between 1998-2008 will be agriculture and that today the average farm-operator household earns only 14% of its income from the farm and the rest from off-farm employment (p.1). Mittal also extends her scope to the rest of the world and points out that agriculture is the source of livelihood for over 40% of people on earth most of which are small-scale and subsistence farmers (like those mentioned earlier from the Chinese countryside) who constitute 75% of the world’s poor (pp.1-2). Her main argument is that the inalienable human right of access to food and water has been undermined by international financial institutions. She explains here;

Instead of ensuring the right to food for all, these institutions have created a system that prioritizes export-oriented production and has increased global hunger and poverty while alienating millions from productive resources such as land, water, and seeds... The focus on export crops for trade has meant increasing yields, with farmers becoming dependent on chemical inputs. Many have stopped rotating their crops, instead devoting every acre to corn, wheat, or some other commodity crop and creating vast monocultures that require still more chemicals to be sustained. This has destroyed our biodiversity. (p.2-3)

The negative impacts of the current global food system do not differentiate between developed and developing countries. Farmers everywhere are struggling to make ends meet. Hassan explains how industrial agriculture has exacerbated this problem below;

It's clear that industrial agriculture is not a system focused on producing food -- rather, it's a system that, given a choice, is more concerned with producing commodities. Commodities typically require the intervention of a processor before they can be eaten. The industrial agriculture complex is built on this fact. Non-industrial food systems, on the other hand, are more concerned with producing food -- something that does not require an intermediary processor to sit between the farmer and the consumer…Furthermore, in stark contrast to industrial agriculture, healthy local food systems deal with hundreds of species, not simply with four or five commodities.”

Thus, communities that, for millennia, have had access to a wide variety of edible plants and legumes within their reach, are now being overrun by a few specific crops that industrial agriculture has deemed to be profitable commodities. The decline of rural culture has not happened by accident. Land availability and access are a global issue as multinational firms continue to buy up agricultural “real estate” either for development or commodity crop production. This “real estate” used to be family and community farms. Likewise, land degradation and the loss of agriculture land and forest cover for commodity crop production and real estate development are ubiquitous across the globe. The human element is harder to quantify but Hassan manages to clarify what is at stake from a culturally and socioeconomic standpoint in this excerpt;

All healthy cultures, be they urban or rural, can be thought of as being 'thick' with choices. The 'thicker' a culture, the more resilient it will be to catastrophe and dramatic change. In a “thick” culture if your crop fails or some disaster strikes you always have a handful of choices left open to you. While they may well be unpleasant choices, they ensure that you or your family won’t starve. In contrast, declining cultures can be thought of as 'thin' with choices. If the crop fails or you lose your job there are no other choices left within your culture. (2005)

These cultural changes and their associated “thinning” of options for poor populations are particularly worrisome when viewed in parallel with current predictions concerning climate change.
In reference to current projected climate change impact studies John Reilly explains in Global Climate Change and Agricultural Production that the productivity of agriculture at most locations may change significantly. He continues here;

Some currently highly productive areas may become much less productive. Some currently marginal areas may benefit substantially while others may become unproductive. Crop yield studies show regional variations of +20, 30 or more percent in some areas and equal size losses in other areas. Current evidence suggests that poleward regions where agriculture is limited by short growing seasons are more likely to gain while subtropical and tropical regions may be more likely to suffer drought and losses in productivity…Thus, policy must retain flexibility to respond as conditions change. (pp. 237-238)

These predictions could have immense impacts on communities where food and water are already inaccessible, unavailable and/or hard to afford. Reilly explains that, “feedbacks among biophysical, economic, social and technological mechanisms are likely to accentuate the uneven distribution of climate change impacts between developed and developing countries” and that “the developing countries are presently the least able to make the necessary adjustments” (p.329). Since there is very little room for error in impoverished communities around the globe, Reilly asserts that, “improving the resilience of food production and minimizing risks against weather variability are essential if agriculture is to meet the challenges of ensuring food security, raising rural employment in developing countries and protecting natural resources and the environment” (p.329). Next, resilience of a different kind - public health - will be examined.

The global impact of the rise of industrial agriculture and the policies and lifestyle changes that have followed in its wake have had clear and stark effects on public health. Pretty explains some of the most worrisome trends concerning public health from a global perspective;

Food now largely comes from dysfunctional production systems that harm environments, economies and societies: and yet we seem not to know, or even care overmuch. The consequences of food systems producing anonymous and homogenous food are obesity and diet-related diseases for about one tenth of the world’s people, and persistent poverty and hunger for another seventh” (p.3).

As if these numbers aren’t staggering enough, according to Roland Sturm, an economist with the RAND Corp., a non-profit think tank, “about 3% of people [in the U.S.], or 6.8 million adults, were morbidly obese in 2005, up from 2% or 4.2 million people in 2000” and George Blackburn, associate director of nutrition at Harvard Medical School, calls the swiftly growing percentage of severely obese people a catastrophe because “the disability, the discrimination and the health care costs for this population are enormous" (Hellmich, 2007). As the mismanagement of land and natural resources shows itself at the front end of today’s food production, so the mismanagement of human health shows itself at the back end.

The seemingly indirect nature of this relationship has allowed the connection between public health and the inequities and inefficiencies of the global food system to go largely undiagnosed heretofore. However, rising energy costs (as well as the work local food system planners, farmers and consumers) are bringing new and much needed attention to the issue due to the of the current system’s vastly inefficient (and inequitable) distribution system. The issue of food-borne illness has also brought this issue closer to the forefront of the public dialogue as well. Pretty clarifies the economic rationale for food system reform in explaining that the desire for ever-cheaper foods and industrial farming practices are responsible for frequent recent outbreaks of food-borne illness the costs of which are enormous. Pretty references the Institute for Medicine at the National Academy of Sciences, the U.S. Department of Agriculture and the World Health Organization estimate the food-borne illnesses in the U.S. cost between US $34 billion and US $110 billion per year (p.64). In addition, Pretty explains that;

“This extraordinary problem…is worsened by antibiotic resistance, brought on by overuse of antibiotics for livestock growth promotion and over-prescription in medicine. Twenty-three thousand tones of antibiotics are used in the U.S. each year, of which 11,000 are given to animals, four-fifths of which is just for growth promotion The U.S. Centres for Disease Control say: antimicrobial resistance is a serious clinical and public health problem in the U.S. (p.64).

For those who would like to justify the present state of the food system with the argument that in order to feed our growing population safely we must accept some negative externalities, the quotations above show that our current trajectory is, put simply, unacceptable. How and what we eat is creating health problems for an increasing percentage of the population and at the same time weakening the health care systems’ arsenal of defenses from both the standpoint of producing antibiotic resistant bacterial strains and channeling many healthcare dollars into the treatment of preventable diseases.

In countries where health care is unaffordable and/or inaccessible, even non-antibiotic resistant bacterial strains often prove to be tantamount to certain death for large numbers of people. Despommier concedes the point that, “a reliable food supply has allowed for a healthier life style for most of the civilized world,” but points out a few of the most worrisome public health issues connected with the current agricultural system here;

The very act of farming has created new health hazards. The transmission of numerous infectious disease agents - influenza, rabies, yellow fever, dengue fever, malaria, trypanosomiasis, hookworm, schistosomiasis - occur with relentlessly devastating regularity at the tropical and sub-tropical agricultural interface. Emerging infections, many of which are viral zoonoses (e.g., Ebola, Lassa fever), rapidly adapt to the human host following encroachment into natural environments. Exposure to toxic levels of some classes of agrochemicals (pesticides, fungicides) and trauma are two other significant health risks associated with traditional agricultural practices.

In some regions of the world with working infrastructure, however, sewage and water treatment systems have managed to reduce human exposure to just such bacterial strains and myriad of pathogens. Lee points out, however that these “systems designed to channel waste away from people as quickly as possible have improved human health while damaging the environment in other ways” (p.17). She continues by explaining the following;

When rainwater runs off pavement and into drains and sewers, the rivers at the end of the pipes flood more often and more severely than would be the case if plants, soil and wetlands soaked up some of the deluge. Much as storm drains short-circuit the water cycle urban waste disposal systems disrupt the nutrient cycle. (p.17)

To illustrate how incredibly high the environmental tradeoff continues to be for many of these systems, Lee presents New York City as an example. Lee asserts that “roughly half of the food brought into New York City is transformed into human energy; the other half is shunted to sewers or trucked to increasingly remote landfills” (p.17). She explains that this organic waste is a valuable resource being wasted since it could be composted into a product that strengthens the health and productive potential of agricultural soils. A general lack of understanding and awareness allows these wasteful habits to continue. Vancouver, unlike most cities has an Office of Urban Agriculture with an internationally-known website, www.cityfarmer.org, that has made great strides in spreading awareness on this exact topic amongst many others pertaining to farming the city. Their rather simple strategy concerning composting food waste has been remarkably successful as is described in this excerpt from Sustainable Urban Food Production in the City of Vancouver: An Analytical and Strategy Framework for Planners and Decision-Makers by Robert Barrs);

To encourage composting, Vancouver and sixteen other local municipalities offer compost bins for sale at a highly subsidized price ($25 in 1996). This program seems to have been an outstanding success - 88,000 bins have been distributed in the region so far (16,000 in Vancouver) and 70% of these are used on a regular basis. This has resulted in the diversion of, on average, 250kg/person/year and means that 22,000 metric tonnes of organic waste per year has been saved from the landfills. With the total residential organic waste stream amounting to 210,000 tonnes per year there is still much room for improvement. ( http://www.cityfarmer.org/barrsUAvanc.html)

Apartment dwellers are not left out of the loop as Vancouver also subsidizes worm composting bins which come with a free demonstration workshop. These compact-sized bins are ideal for this segment of the population many of whom tended to be under the impression that they were not able to compost due to lack of suitable space. More innovative and proactive ideas such as this will be explored in the next section.

Urban Agriculture: Cultivating Change and Changing Cultivation

In the quest feed tomorrow’s population, without bringing ecosystems further out of balance and wasting even larger amounts precious resources in the process, urban agriculture is showing much promise both in terms of resource use efficiency and in building resiliency and strengthening communities and the ecosystems that sustain them. In A resilience-based framework for evaluating adaptive co-management: Linking ecology, economics and society in a complex world, Ryan Plummer and Derek Armitage (2007) explain that, “the three central features of resilience are: (1) the ability of a system to absorb or buffer disturbances and still maintain its core attributes; (2) the ability of the system to self-organize; and (3) the capacity for learning and adaptation in the context of change”. They continue here;

Resilience thinking has emerged as one conceptual framework with which to understand change and the multiple, cross-scale interactions in social-ecological systems. Although grounded in the ecological sciences, resilience has increasingly been tested and applied by natural and social scientists to examine a range of ecological communities, linked social-ecological systems, and institutional and organizational arrangements… therefore, a central objective may be to keep social-ecological nor socio-economic systems from moving towards or further into system states or conditions that meet neither ecological nor socio-economic sustainability criteria (i.e., avoiding system ‘flips’ that occur when certain thresholds are reached). (p.65)

In other words, urban agriculture fits into the central objective of a resilience framework by helping cities and their residents re-establish balance and “increase the stock of nature” as Pretty suggested in the “concrete jungles” of the world and the actual jungles as well. In Dream Farms, Mae-Wan Ho extends this point;

The key is a balanced development and growth that’s achieved by closing the overall production cycle, then using the surplus nutrients and energy to support as many different cycles of activities as possible while maintaining internal balance, rather like a developing organism. The ‘waste’ from one production activity is resource for another, so productivity is maximised with the minimum of input and little or no waste is exported into the environment. It is possible to have sustainable development after all; the alternative to the dominant model of unlimited, unsustainable growth is balanced growth. (http://www.i-sis.org.uk/DreamFarm.php)

Urban agriculture can serve as the harbinger of just this sort of change in the developed world as many in the developing world are already well aware of the value of local food production. Even in ancient times, the value of urban agriculture was clear,
Halwell andNierenberg point out that;

The hanging gardens in Babylon, for instance, were an example of urban agriculture, while residents of the first cities of ancient Iran, Syria, and Iraq produced vegetables in home gardens. This is partly because cities have traditionally sprung up on the best farmland - the same flat land that is good for farming is also easiest for constructing office buildings, condominiums, and factories – and partly because the masses of urban dwellers create a perfect market for fresh fruit and vegetables. (p.49)

A sizable portion of the world’s populations still manages to ignore this ancient bit common sense and live outside their ecological means. Even those countries like China, for example, that have decided to emphasize urban agriculture are still underestimating the importance of conserving farmland in the midst of their economic and population boom.
In chapter 3 of State of the World 2007 – Our Urban Future entitled Farming the Cities (2007) Brian Halwell and Danielle Nierenberg establish urban agriculture’s present contribution to the nourishment and livelihood of today’s global urban populations;

The U.N. Development Programme estimates that 800 million people are involved in urban farming worldwide, with the majority in Asian cities. Of these, 200 million produce food primarily for the market, but the great majority raise food for their own families. In a survey conducted for the United Nations, cities worldwide already produce about one third of the food consumed by their residents on average. (p.50)

These impressive figures direct us towards the consideration of the vast untapped potential of urban areas around the world that have yet to cultivate the land upon which they sit. Halwell and Nierenberg then present three examples of cities that are well on their way to realizing the benefits of incorporating urban agriculture into their city’s policies as well as its social fabric. They begin by highlighting the contrasting populations and per-capita income of the three cities and clearly emphasizing urban agriculture’s universal applicability here;

“On the surface, Accra in Ghana, Beijing in China and Vancouver in Canada seem to have little in common. They rage in populations from roughly 2 million in the metropolitan region of Vancouver to more than 14.5 million in Beijing. The per capita incomes are vastly different: about $700 a year in most of Ghana, about $2,200 in Beijing, and more than $32,000 in Vancouver. But take a closer look, digging a little deeper into the backyard and rooftop gardens, and you’ll realize that these city folk share a preoccupation that has thrived since the first cities---raising food. (p.48)

Halwell and Nierenberg then detail the unique challenges and their accompanying successes for each city. They begin with Accra which “has a population of 6 million, including a steady supply of migrants from rural areas and immigrants who seek work in its factories. Because food is expensive, people farm anywhere they can: in backyard plots, in empty lots, along roadsides, and in abandoned dumps”. The approximately 1,000 urban farmers in Accra grow a variety of crops for home use and sale, including “exotic varieties like green peppers, spring onions, and cauliflower, as well as more traditional crops like okra, hot peppers, and leafy greens such as alefi and suwule” (p.48). Halwell and Neirenberg explain that plots vary from just one tenth or one twentieth of a hectare (10 meters by 10 meters) to 20 hectares in the city outskirts.

In Beijing, Halwell and Neirenberg point out, urban agriculture has followed a more scientific pattern as city planners decided in the 1990s that “urban agriculture was an important way to meet the city’s food needs, preserve green spaces, and conserve the region’s water and land resources more efficiently”. In order to encourage the practice, the municipal government began offering courses and assistance for aspiring farmers, surveying existing land use to better understand the extent of urban farming, and attempting to incorporate urban farming into long-term city planning decisions. Halwell and Neirenberg emphasize the economic impact that urban and peri-urban agriculture continue to make in and around the city here;

Today, urban and peri-urban agriculture in Beijing not only provides residents with safer, healthier food, it also keeps farmers in business. Between 1995 and 2003, the income for farmers living just outside of Beijing doubled. The city includes tens of thousands of household farms and more than 1,900 agrotourism gardens for Beijing resident craving some rural experience. Although the share of the city’s population involved in farming is currently very small---just about 1 percent---the municipal government plans to cultivate gardens on 3 million square meters of roof space over the next 10 years.

So, in the midst of urban sprawl and booming economic growth, there is also at least some support and respect for the contributions to urban life and resource efficiency that urban agriculture offers. One major challenge for China as a whole is to begin to emphasize density and utilize urban agriculture to mold livable communities that are inclusive for all its citizens.
Another primary issue for China is water and the lack thereof, Lester Brown points out in Plan B 2.0: Rescuing a Planet Under Stress and a Civilization in Trouble (2006) that;

It is widely assumed that urbanization will continue. But this is not necessarily so. The growing scarcity of water and the high cost of the energy invested in transporting water over long distances may itself begin to constrain urban growth. For example, some 400 cities in China are already facing a chronic shortage of water.

In an March 2007 interview, global food system researcher Rosamund Naylor described the underestimation of water’s finite nature clearly and extends it to include the global perspective as well;

Without an appreciation of how fundamentally important water is, the types of development paths that we have been on have been fundamentally flawed. If the integration of ecosystem goods and services and agricultural development were improved, some of the implication of that would be to have agricultural systems that were much more water efficient. Agriculture is the biggest water user, because we use water recklessly without having to pay a price for it. Water use could be improved in virtually every system on the planet except for the very highly tuned drip irrigation systems that already exist, and then it is a matter of cost and incentive. (Zaks, 2007)

Urban agriculture’s role in addressing the emerging global water crisis is in part a measure of its ability to encourage the general population to appreciate the value of conserving resources within their reach and using them to their utmost potential. On their website (http://www.iwmi.cgiar.org/wwf4/html/action_2.htm) the International Water Management Institute (IWMI) reveals that approximately 75% of the world’s poor depend on rainfed agriculture for their livelihoods. IWMI explains that impoverished populations as well as the general population needs to practice better techniques for capture and conservation of green water (which exists as soil moisture until it is evaporated from wet soils or transpired through plants). An explanation by IWMI is provided below on how this could make agriculture more productive on a smaller area of land as well as prevent soil erosion;

Rainfed agriculture and natural ecosystems have in common that they both depend on the 60% of the rainfall that does not make it into rivers or aquifers, but is stored directly in the soil as “soil moisture” - the green water. Increasing the productivity of green water used in rainfed agriculture has great potential to reduce the area needed for agriculture… Capturing a larger share of rainfall close to where it falls not only increases the water available to plants and people in that location, but also prevents soil erosion.

The IWMI recommends the following methods of rainwater harvesting; (1) capturing water for domestic use, e.g. by collection of rain falling on rooftops in cisterns; or (2) replenishing green water, e.g. through stone bunds on the contour line; or (3) increasing blue water available locally, e.g. through small check dams that either increase recharge to the groundwater or store water in small reservoirs.

Techniques such as these, the IWMI explains, are already in use by hundreds of thousands of communities, particularly in India, to increase water for domestic, agriculture and ecosystem uses.
One example of a successful comprehensive management plan in the developed world was recently put into action by New York State with its support for sustainable agriculture in the 500,000 hectare Catskill-Delaware watershed complex. Pretty explains that “New York City gets 90 per cent of its drinking water from these watersheds, some 6 billion litres a day” (p.66). Pretty continues by explaining when and why a water management strategy planning process began here;

In the late 1980s though, the city was faced with having to construct a filtration facility in order to meet new drinking water standards, the cost of which would be US 5 billion to US $8 billion dollars, plus another US $200 million to US $500 million dollars in annual operating costs. One third of the cropland in the watershed would have to be taken out of farming in order to reduce run-off of eroded soil, pesticides, nutrients and bacterial and protozoan pathogens.

Due to the forethought of the parties involved, instead of footing the bill for this misguided project and the environmental degradation that would have followed inevitably in its wake, the city opted for a collaborative approach with farmers. New York City supported the establishment of a Watershed Agricultural Council in the early 1990s, a partnership between farmers, government and private organizations to at once protect the city’s drinking water supply and sustain the rural economy. The partnership works on whole-farm planning with each farm, “tailoring solutions to local conditions in order to maximize reductions in off-site costs”. The first two phases of the program, leading to the 85 per cent target in pollution reduction, cost approximately US $100 million, a fraction of what the cost of the filtration plant and its enormous annual costs (financial and environmental) would have been. Pretty points out that this type of joint agri-environmental management benefits taxpayers, farmers, the environment, and rural economies. He succinctly states that, “If it is clean water that is required, the value of an agricultural landscape can be substantial” (p.66). These types of strategies are needed around the globe as cities get larger and more populated, water must be managed well regionally and locally. The IWMI delineates which geographic areas would be particularly well-served by the adoption of better green water conservation strategies here;

Improving productivity of rainfed systems through improved land management techniques and agricultural production systems, use of terracing, contouring and micro-basins are important measures in maximizing rainfall infiltration into the soil to increase yields, especially for farmers in Sub-Saharan Africa, Latin America and South Asia. Conservation or zero tillage - where crop residue is used as mulch - is a promising technology. (IWMI)

Since much agricultural production is conducted in and around the periphery of today’s cities, these areas are on the frontlines of the battle to limit unnecessary losses of water and also soil. Pretty points out that

Long-term agricultural experiments in both Europe and North America indicate that soil organic matter and soil carbon are lost during intensive cultivation…but both can be increased with sustainable management practices. The greatest dividend comes from the conversion of arable land to agroforestry: there is a benefit from both increased soil organic matter and the above-ground woody biomass…There is now good evidence to show that sustainable agricultural systems can lead to the annual accumulation of 300 to 600 kilogrammes of carbon per hectare, rising to several tones per hectare when trees are intercropped in cropping and grazing systems. (p.68)

In urban areas, areas interspersed with trees and agriculture i.e. agroforestry would be ideal for both quality of life and environmental benefits such as water and air quality. These areas would also serve as prime infiltration areas for green water and would prevent urban soil erosion which is a major issue globally. The treatment of soil in the urban context is the topic of the this section. In Urban Soils: Applications and Practices Phillip J. Craul explains that;

Erosion from urban areas is even more severe than that from agricultural land. For example, annual sediment yield amounts to 218 tons per acre (489 metric tons per ha) from construction sites in Washington, DC. Annual sediment yield from agricultural land may range from 5 to 20 tons (11 to 45 metric tons per ha) per acre and less than 1 ton from forest land. (p.260)

Thus, it is clear that urban areas are presently contributing far more than necessary to soil loss and associated effects on agricultural production and sedimentation of the world’s waterways.
R.P.C. Morgan explains in Soil Erosion and Conservation (2005) that “soil erosion costs the U.S economy between US $30 billion (Uri & Lewis 1998) and US $44 billion (Pimental et al. 1993) annually”. Morgan points out that these costs result from the on-and off-site effects of erosion. The on-site effects are of particular importance on agricultural land where;

the redistribution of soil within a field, the loss of soil from a field, the breakdown of soil structure and the decline in organic matter and nutrients result in a reduction of cultivable soil depth and a decline in soil fertility. Erosion also reduces available soil moisture, resulting in more drought-prone conditions… The loss of soil fertility through erosion ultimately leads to the abandonment of land, with consequences for food production and food security and a substantial decline in land value. (p.1)

Morgan then gives a succinct description of the soil erosion’s off-site problems here; Off-site problems arise from sedimentation downstream or downwind, which reduces the capacity of rivers and drainage ditches, enhances the risk of flooding, blocks irrigation canals and shortens the design life of reservoirs…Sediment is also a pollutant in its own right and, through the chemicals adsorbed to it, can increase the levels of nitrogen and phosphorus in water bodies and result in eutrophication. Erosion leads to the breakdown of soil aggregates and clods into their primary particles of clay, silt and sand. Through this process, the carbon that is held within the clays and the soil organic content is released into the atmosphere as CO2.”

These issues continue to worsen as development trends speed up and spread out over time.
Craul explains here how vegetation can impede these continued losses associated with common urban land uses;

In undisturbed vegetation, most of the destructive kinetic energy of rainfall is absorbed by the vegetation and litter, and the plants protect the soil from erosion. Soil compaction from construction or recreation causes decreased infiltration rates and consequent increases in surface runoff and erosion. (p.252)

Craul further explains that “Different plant cover affords different degrees of protection, so that human influence, by determining land use, can control the rate of erosion to a considerable degree” (p.2). In Soils in the Urban Environment, Peter Bullock and Peter J. Gregory explain that in order to truly realize the productive erosion prevention and agricultural production potential of urban land and its uses, the definition of soil must be modified to: “Any unconsolidated mineral or organic material at the Earth’s surface that has the potential to support plant growth.” They explain that this is necessary due to the fact that

A whole range of materials [are] likely to be found in an urban context, from loose, unconsolidated, man-made material unmodified by soil-forming processes, to undisturbed naturally developed’ soils [and also] materials which in their present state are too toxic to support plants, but have the potential to do so, if their toxicity problems are corrected. (p.5)

They also explain that this was not always the case, before the Industrial Revolution, urban soils were much healthier and “relatively unadulterated by non-degradable wastes”.
The historical explanation for this occurrence using Europe as an example is delineated below;

Until the fourteenth century most western European towns contained a mixture of rural and urban activities, with sufficient space within the walls to pasture animals and grow crops…mediaeval cities had houses built of mud and timber with roofs of thatch, materials which in the present would be called biodegradable. From their houses and premises the people ‘threw their garbage, litter and offal into the street from doors and windows without regard to amenity or sanitation. Thus, urban areas up to the fourteenth century produced waste materials which were returned and incorporated into the soil, together with a few artefacts. (p.28)

The changes in industrial practices which took place about the beginning of the eighteenth century, collectively called the Industrial Revolution, began to increase amount of urban waste materials and to change their content as industrial activities grew in importance. (p.28) The process of industrial change has continued and in the past few decades many of the former heavy industries have closed and their sites have become disused or have been converted to alternative uses. In some cases sites have been used for many different successive purposes, some of which have resulted in soil contamination as waste materials have been added to the soil.
Craul continues this timeline with his historical viewpoint of erosion and the growing awareness of its global impacts here;

Since the 1930s the need for erosion control has been driven largely by concerns over food production and security of food supply both for individual countries and for the increasing world population. Since the 1970s, there has been increasing concern about the environmental damage caused by erosion. Although much of this damage is associated with sediment derived from agricultural areas and the chemical adsorbed to it, problems can also arise from erosion on road banks, urban land, pipeline corridors and recreational areas. The people whose activities may contribute to erosion and who may be affected by any damage are now a much wider group than farmers. Erosion affects whole communities. (p.261)

Craul then points out that, “the next few decades will reveal whether spatial distribution of erosion will alter in relation to changes in climate and the resulting human responses, particularly changes in land cover” (p.261). He also states that areas previously unaffected by erosion will likely be affected. Craul does, however, present preventative and restorative measures. One of these is the “use of existing site materials as a component of a designed mix together with sources of recycled materials such as composted organic wastes and mineral materials”. Craul asserts that, “the technology of recyclable material use in constructing soil has progressed to a sufficient degree that permits the serious consideration of a totally sustainable soil. That is, a soil composed entirely of recyclable materials and containing no renewable resources.” (p.6) Pretty presents another restorative measure in the replacement of conventional agricultural methods (including heavy tillage and pesticide use) with organic methods (like low- and no-till agriculture) that support soil health and biodiversity. Pretty presents some supportive information here;

One study in the UK compared paired organic and non-organic farms , and concluded that organic agriculture produces UK £75 of UK £125 per hectare of positive externalities each year, with particular benefits for soil health and wildlife. As there are 3 million hectares of organic farming in Europe, the annual positive externalities could be UK £300 million, assuming that benefits hold for the many organic farming systems across Europe. (p.66)

Pretty further explains that sustainable organic agriculture has led to “an average 93 per cent increase in per hectare food production. The relative yield increases are greater at lower yields indicating greater benefits for poor farmers” (p.84). In order to illustrate how sustainable urban agriculture can impact a community, let us now examine the impact it has made in Rosario, Argentina and Villa Maria del Triunfo, Peru. Halwell and Nierenberg describe the first of these two case examples here;

In Rosario, Argentina, where farming in the city was initially a response to the nations’s financial crisis, officials are trying to establish it as an integral part of urban life. They created the Programa de Agricultura Urbana (PAU) a cooperative venture that unites urban farmers, municipal officials, agricultural experts, and representatives of non-governmental organizations. The PAU helped urban farmers secure and protect agricultural spaces, take advantage of value-added agricultural products, and establish new markets and market systems. Soon, seven farmers’ markets and more than 800 community gardens--- supporting some10,000 farmers and their families --- had sprouted up throughout the city. The cooperative also involved residents of Molino Blanco, a low-income housing project, in the design and construction of a large garden park that includes walking paths, soccer fields, and large designated areas where people can raise food. (p.64)

The momentum of community participation shows itself in this example. Urban agriculture is powered by people and Rosario is beginning to be transformed by self-determination and pride that its people feel. The project was possible due a small investment of time, funds and organization from city officials. It deserves to be copied in other cities.
Now, the case example from Peru incorporates the issue of soil erosion that was examined in depth earlier;

In the erosion-prone city of Villa Maria del Triunfo in Peru, where 83 percent of all urban farmers are women for whom this is the sole source of income, city officials surveyed the 70-square-kilometer urban landscape to determine what share was suitable for farming. By 2004 the municipality had established a dedicated urban agriculture office in its economic development branch; had earmarked money to subsidize seed, fertilizer, and other inputs for city farms; and encouraged an increase in local processing and marketing. The program helped create 399 family and community plots on formerly vacant land, examined sources of irrigation water, developed a municipal consolidation plan for urban agriculture through 2010, and formed a multi-stakeholder advisory group that supports ongoing implementation of the plan. (p.64)

These two examples present how much impact urban agriculture can have at the local, city-wide level when the government gets behind the project. Next, we will examine how urban and sustainable organic agriculture has played a major role in the transformation of an entire country.
Cuba is that country and in an August 13, 2006 article entitled “Cuba’s agricultural revolution an example to the world”, Andrew Buncombe explains that; Spurred into action by the collapse of the Soviet Union and the disastrous effect this had on its subsidized economy, the government of Cuba was forced to take radical steps to feed its people. The solution it chose -- essentially unprecedented both within the developed and undeveloped world -- was to establish a self-sustaining system of agriculture that by necessity was essentially organic.

Buncombe quotes Laura Enriquez, a sociologist at the University of California-Berkeley, as saying, "What happened in Cuba was remarkable. It was remarkable that they decided to prioritize food production. Other countries...exported 'what they were good at' and imported food. The Cubans went for food security and part of that was prioritizing small farmers”. Buncombe explains that “Cuba is filled with more than 7,000 urban allotments, or organoponicos, which fill perhaps as many as 81,000 acres”. These organoponicos have been established on tiny plots of land in the center of “tower-block estates or between the crumbling colonial homes that fill Havana” and have only existed in their current form since the late 1980s. Prior to that time, Cuba's economy was extraordinarily reliant on subsidies from the Soviet Union and its agricultural system’s primary aim was to produce as much sugar cane as possible, which the Soviets bought at more than “five times the market price, in addition to purchasing 95 percent of its citrus crop and 73 percent of its nickel. In exchange, the Soviets provided Cuba with 63 percent of its food imports and 90 percent of its petrol”. This relationship made Cuba extraordinarily vulnerable and, thus, the collapse of the Soviet hit Cuba extremely hard when subsidies (which including a large percentage of Cuba’s food supply) were halted almost overnight. This time is known as the Special Period. Cuba’s population felt the pinch with as Buncombe cites, “figures produced by the U.N. Food and Agriculture Organization suggest[ing] that the daily calorie intake of the average Cuban fell from about 2,600 calories a day in the late 1980s to between 1,000 and 1,500 by 1993”. This meant that the average Cuban was forced to get by on about half the food they had been eating. With no subsidies and limited resources, the Cuban regime took the decision to work with what they had within their reach to maximize food production. Buncombe explains here how this necessitated the sustainable organic agriculture approach;

By necessity, this meant a back-to-basics approach; with no Soviet oil for tractors or fertilizer it turned to oxen, with no Soviet oil for its fertilizer and pesticide, it turned to natural compost and the production of natural pesticides and beneficial insects. It is estimated that more than 200 locally based centers specializing in biopesticides annually produce 200 tons of verticillium to control whitefly, and 800 tons of beaveria sprays to control beetles. (2006)

Buncombe cites Pretty who recently wrote about Cuba’s ingenious methods here;
Cut banana stems baited with honey to attract ants are placed in sweet potato fields and have led to control of sweet potato weevil. There are 170 vermicompost centers, the annual production of which has grown from three to 9,300 tons. Crop rotations, green maturing, intercropping and soil conservation have all been incorporated into polyculture farming. (2006)

The most wonderful thing about these methods is that together they have made Cuba one of the most sustainable countries on the planet while at the same time improving the quality of life and the population’s public health. Buncombe explains here; Annual calorie intake now stands at about 2,600 a day, while UNFAO estimates that the percentage of the population considered undernourished fell from 8 percent in 1990-92 to about 3 percent in 2000-02. Cuba's infant mortality rate is lower than that of the U.S., while at 77 years, life expectancy is the same. (2006)
The new system is also vastly more energy-efficient since it is more human labor-intensive instead of machine-intensive work. Buncombe quotes Fernando Funes, head of the national Pasture and Forage Research Unit, who told Harper's magazine: "In that old system it took 10 or 15 units of energy to produce one unit of food energy. At first we did not care about economics, (but) we were realizing just how inefficient it was” (2006). Cuba is being studied by experts like Pretty so that its example can be translated to other parts of the world.

Now, the developed world has recently begun to ring in a few urban agricultural success stories of its own. Vancouver is, perhaps, one of the most notable in that 44 percent of Vancouverites grow vegetables, fruit, berries, nuts, or herbs in their yards, on their balconies, or in one of the 17 community gardens located on city property (Halwell & Neirenberg, 2007, p.48). Urban farming in Vancouver is supported its naturally mild temperatures which extends the growing season to almost twelve months of the year. Halwell and Neirenberg point out that in Vancouver;
Farming the city is part of a much larger movement that includes restaurants buying from local farms, buying clubs in which neighbors subscribe to weekly deliveries of produce, and the heavily attended Feast of Fields harvest festival twice a year on a farm outside the city that exposes city folk to rural life. (p.49)

This began as a grassroots movement a little more than a decade ago unlike Cuba which took a top-down approach. What is surprising is the comparable successes that both approaches have had in a relatively short period of time. Mlozi explains how the movement developed here;
In 1995, the city of Vancouver had 12 community gardens as most urban dwellers gardened in their households. This made the city council to consider allocating more areas for community gardening. Although common in most Canadian cities, community gardening has had a long history of being disapproved by the city authorities. In the city of Vancouver, for instance, “community activists helped to push the Vancouver Parks Board, an elected body, to adopt the first official community gardening policy document in the region in 1996…Also, activists have pushed the Greater Vancouver Department of Parks and Recreation to allocate the 7-acre land, a former penal institution to set up 420 community gardens plots for urban dwellers. (n.d.) The City of Vancouver now has a very well-known City of of Urban Agriculture that was mentioned earlier and multiple levels of government are working productively together to encourage density while maintaining quality of life in and around the city.

British Columbia’s Agriculture Land Reserve (ALR) is also playing a key role in preventing sprawl from the city’s continued population boom. Elisa Murray reported that according to “Sprawl and Smart Growth in Greater Vancouver,” a report released today by Seattle-based Sightline Institute (formerly Northwest Environment Watch) and Vancouver-based Smart Growth BC, “From 1986 to 2001, Greater Vancouver’s share of residents living in compact communities increased from 46 percent to 62 percent—in striking contrast to Seattle, which had only 25 percent of residents in compact communities in 2000” (2002). Other findings in the report are that, “Greater Vancouver’s population increased by nearly 50 percent between 1986 and 2001, a higher annual growth rate (2.6 percent) than many developing-world megacities such as Jakarta, Indonesia. The study also found that, “Greater Vancouver has met both challenges by channeling growth inward into compact neighborhoods. In contrast, greater Seattle has grown outward at the expense of both farmland and transportation choices”. Also a full “62 percent of Greater Vancouver’s residents now live in compact neighborhoods (defined as having 12 residents or more per acre), up from 57 percent just five years ago”. The study also compares Greater Vancouver’s ability to contain sprawl with that of Greater Seattle here;

Greater Seattle spreads across three-quarters more land per resident than Greater Vancouver. If Greater Vancouver had the same overall population density as Seattle about 650 square kilometers of additional land would be covered with suburban development—an area equivalent to all the remaining developable land in the Greater Vancouver Regional District (GVRD), plus four-fifths of the remaining agricultural land.

Also, the report estimates that Greater Vancouver could add another million residents without developing any new rural land through a slight increase in density throughout the region and the dedication of just “5 percent of current lower-density residential areas to new pedestrian-oriented neighborhoods of more than 40 people per acre” (2002). Pretty discusses how Vancouver has seen such gains in terms of sustainability in that;

The Food Policy Council of the City of Vancouver in Canada now uses urban agriculture to strengthen the connections between its food and its sustainability policies, while a growing number of developing country cities link urban agriculture to their food security agenda. Together with less agrarian developments, as in information and communications technologies, urban agriculture is stalling, if not erasing, the compartmentalization of spaces and times that a Western generation has come to know. These developments are transforming the way in which our cities are laid out and, more immediately, the way in which they work. No doubt these transformations will profoundly affect the very meaning of urbanity and rurality in the future. (p.25)

As Pretty eloquent prose clearly states, Vancouver is evolving into a new type of city that does not differentiate itself from the land and ecosystems that sustain it. City and country are no longer opposed in nature each exploiting the other in different ways. Instead, a new balance is being negotiated, one in which the most beneficial use of the land is being protected and new ways to increase the stock of nature are being generated.

The Humane Metropolis and Vertical Farms: Seeds for the Cities of Tomorrow

In an article entitled “The 'Humane Metropolis' -- Are We Ready?” (2007), Neal Peirce explains that for a city to be “green, healthy, sociable, civic, and inclusive, it must foster humans’ connections to the natural world”. He quotes this piece of Anne Spirn’s writing,``Nature in the city, must be cultivated, like a garden, rather than ignored or subdued” and mentions the need for “renewed attention to welcoming urban parks, from entire ``green necklace'' systems within metro areas to the emerald-green sanctuary of small vest-pocket parks”. He emphasizes that, “community gardens, green roofs, street trees and planted medians all count -- and today more than ever as antidotes to the ``urban heat island'' phenomenon and the spread of global warming-inducing greenhouse gases”. He then extends the vision of a human metropolis by explaining that the “recovery of barren industrial ``brownfields'' is one companion strategy; another is creating ecological habitats on such bleak sites as sanitary landfills”. He presents the example of “an experiment now to nurture biodiversity atop a literal landscape of death -- the Fresh Kills landfill on New York’s Staten Island, where the World Trade Center debris was deposited”. Peirce explains that these efforts are closely aligned with ``green blue'' strategies -- handling urban water in more sensitive ways, by ``daylighting'' streams once enclosed in concrete pipes and by filtering stormwater more slowly through swales and other forms of landscaping that avoid big engineering solutions in favor of nature's more modest but ecologically sound ways”.

Public health is also brought into the human metropolis mix as Peirce brings in public health researcher Anne Lusk’s recommendations for the creation of a humane metropolis. To reduce asthma-inducing auto, truck and industrial pollution, and now to attack the obesity epidemic impacting American society, Lusk suggests the need for many more linear urban parks (which could also be used at least in part to grow fresh produce), more stores offering fresh produce especially in rundown areas. It is clear that the tenets and benefits urban agriculture are central to this new and growing movement. Pierce expands his explanation here;

The ``humane metropolis'' advocates, bent on shared streets and spaces, have no single solution. Their idea is simply to protect and create all possible natural areas -- parks, greenways, forest tracts -- fostering a shared sense of ``ecological stewardship.'' They support efforts toward environmental justice, so that low-income areas are not burdened with undue, damaging pollution. And, of course, they aim to create welcoming, green places in cities -- nature within urban places that will draw people together. Adding, they hope, social justice: as Ford Foundation official Carl Anthony writes, ``issues of race and poverty, social environmental justice, must be central to the way we envision a truly humane metropolis, bringing together people and nature in the 21st century.”

The main thrust of the humane metropolis movement is to cultivate hope and energy to strengthen the social and environmental fabric of today’s cities and those of tomorrow. Urban agriculture’s role in this movement is clear in that it supports this cultivation in a hands-on experiential manner in addition to bringing back a real sense of pride and responsibility to its participants and an appreciation of natural beauty even for those who are only casual observers. A humane metropolis of the future, however, will still be expected to meet the complex and growing demands of its diverse population. The ecosystem services that cities of today use to provide for their populations is vastly unsustainable. There are some ideas involving urban agriculture that could help fulfill some of these high expectations. In his Vertical Farm Essay, Despommier explains one of them, vertical farms, here;

If traditional farming could be replaced by constructing urban food production centers - vertical farms - then a long-term benefit would be the gradual repair of many of the world’s damaged ecosystems through the systematic abandonment of farmland. In temperate and tropical zones, the re-growth of hardwood forests could play a significant role in carbon sequestration and may help reverse current trends in global climate change. Social benefits of vertical farming include the creation of a sustainable urban environment that encourages good health for all who choose to live there; new employment opportunities; fewer abandoned lots and buildings; cleaner air; and an abundant supply of safe drinking water.

In a recent article for New York Magazine, Lisa Chamberlain explains that Dickson Despommier began developing the vertical-farming concept six years ago, and that he has been contacted by scientists and venture capitalists from the Netherlands to Dubai who are interested in establishing a Center for Urban Sustainable Agriculture. Chamberlain further explains that Despommier estimates it could take a working group of agricultural economists, architects, engineers, agronomists, and urban planners five to ten years to figure out how to “marry high-tech agricultural practices with the latest sustainable building technology”. Despommier believes that “only by allowing significant portions of the Earth’s farmland to return to forest do we have a real chance of stabilizing climate and weather patterns and that merely reducing energy consumption will at best slow global warming. Chamberlain explains that;

Depending on the crops being grown, a single vertical farm could allow thousands of farmland acres to be permanently reforested. For the moment, these calculations remain highly speculative, but a real-life example offers a clue: After a strawberry farm in Florida was wiped out by Hurricane Andrew, the owners built a hydroponic farm. By growing strawberries indoors and stacking layers on top of each other, they now produce on one acre of land what used to require 30 acres. (Chamberlain, n.d.)

There are also ancillary benefits to growing crops in a controlled environment: all food could be grown organically, without herbicides, pesticides, or fertilizers, eliminating agricultural runoff. Chamberlain points out that 80 percent of the world’s population will be living in urban areas by 2050, which warrants, Despommier believes, their adoption of vertical farms as their primary means of agricultural production. She explains that Despommier cites the already existing density and infrastructure in cities needed to support vertical farms, and that super-green skyscrapers could supply “not just food but energy, creating a truly self-sustaining environment”.

In order to put into motion this and other urban agricultural projects, much more policy integration will be required. In the case of vertical farms, it may be the private sector that begins construction but it will be the cities themselves that formulate the overarching sustainability principles that ensure their success. Pretty asserts that “policy integration is vital; yet most policies seeking to link agriculture with more environmentally sensitive management are still highly fragmented” (p.72). This is perhaps the most important element of developing regional and more comprehensive urban agricultural initiatives. Once the public and private sector join forces with the general population to strengthen local food systems, the many benefits urban agriculture offers will be realized. Until then, only the inhabitants of cities that have been part of the first wave of urban agricultural policy integration will fully appreciate what it is like to live in a city where one can feel a sense of pride, connection and responsibility for the land within their reach – the land that is , after all, merely borrowed from future generations of urban farmers.

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