Let’s make climate change talks inclusive M. S. SWAMINATHAN & KANAYO F. NWANZE

Climate-resilient sustainable agriculture requires knowledge. Successful projects such as these can provide a model for others to follow. Knowledge transfer that brings the benefits of research from the laboratory to the farm is essential.
The HinduClimate-resilient sustainable agriculture requires knowledge. Successful projects such as these can provide a model for others to follow. Knowledge transfer that brings the benefits of research from the laboratory to the farm is essential.

Price volatility and the persistence of widespread and hidden hunger underline the need for enhancing the productivity and profitability of smallholder agriculture in an environmentally sustainable manner.

When world leaders sit down again to discuss climate change, we hope that the people who live and work on the world’s 500 million small farms will be with them, at least in spirit. Their voice — and the issue of agriculture as a whole — has, for too long, been missing from the conversation. But without increased support to smallholder farmers now, the number of hungry people will grow, and future food security will be placed in jeopardy.

The upcoming 17th Conference of the Parties (COP17) to the United Nations Framework Convention on Climate Change (UNFCCC), and the United Nations Conference on Sustainable Development (UNCSD) in Rio de Janeiro in June 2012 — marking the twentieth anniversary of the landmark Earth Summit that produced Agenda 21, “a roadmap” for sustainable development — will both need to ensure that agriculture and the world’s smallholder farmers are high on the agenda if we are to overcome the many challenges we face in achieving the Millennium Development Goal 1.

The front line

In the last 20 years the global population has risen from about 5.3 billion to seven billion; the reality of climate change has been accepted beyond doubt; and the number of hungry people in the world has remained stubbornly around the one billion mark. Meanwhile, aid to agriculture has only just recently begun to pick up after decades of stagnation. More needs to be done — a lot more — and supporting smallholder farmers must be at the heart of any agenda.

The rural poor across the world, including India, have contributed little to human-induced climate change, yet they are on the front line in coping with its effects. Farmers can no longer rely on historical averages for rainfall and temperature, and the more frequent and extreme weather events, such as droughts and floods, can spell disaster. And there are new threats, such as sea level rise and the impact of melting glaciers on water supply.

How significant are small farms? As many as two billion people worldwide depend on them for their food and livelihood. Smallholder farmers in India produce 41 per cent of the country’s food grains, and other food items that contribute to local and national food security. Small farmers cannot be ignored, and special attention must be given to the most vulnerable groups — particularly women, who make up a large percentage of farmers in the developing world.

Small farms also add up to big business: In the world’s 50 least developed countries, agriculture is the backbone of the economy, accounting for 30 to 60 per cent of Gross Domestic Product and employing as much as 70 per cent or more of the workforce. Addressing the plight of smallholders isn’t just a matter of equity, it’s a necessity if we are going to be able to feed ourselves in the future. Smallholders farm 80 per cent of the total farmland in sub-Saharan Africa and parts of Asia. If we don’t help them to adapt to climate change, their achievements — feeding a large portion of humanity — will be endangered.

With appropriate support, smallholders can play a key role in protecting our environment, for example through actions that contribute to carbon sequestration and limit carbon emissions (planting and maintaining forests, engaging in agro-forestry activities, managing rangelands and rice lands, and watershed protection that limits deforestation and soil erosion).

To continue farming in a sustainable way in the face of climate change, rural women and men need to be given the resources to cope with the challenges. Smallholder farmers need support such as resilience-building technologies (including drought- and salt-tolerant seed varieties and new methods of rainwater harvesting), and training in sustainable practices of conservation agriculture, such as minimum-till farming to reduce erosion and moisture loss. Investing in adaptation measures now will be far less costly than in the future.

The International Fund for Agricultural Development (IFAD) and the M.S. Swaminathan Foundation, together with the government of India and other partners, have undertaken a range of projects to do just that.

For example, in Tamil Nadu, we have been supporting rural communities to produce and market nutri-cereals like millet, which can easily grow in dry and arid environments. We worked with smallholder farmers to use simple techniques to increase their yields, while also helping rural women create and market modern recipes — for example, a millet malt drink now being sold in major health food stores in India. The result has been not only increased food for the community, but also increased income and non-farm employment opportunities.

To help farmers adapt to increasingly dry conditions, a programme in Chhattisgarh has expanded cultivation of traditionally produced Niger seed oil, which grows well in areas that receive little rain. Land and forest regeneration were promoted to improve soil structure and moisture levels, and solar energy technology and biogas digesters have been introduced, which reduce greenhouse gas emissions as well as the need for fuelwood. Another project in the northeast has helped restore degraded jhumland and has benefited almost 40,000 households in 860 villages.

Climate-resilient sustainable agriculture requires knowledge. Successful projects such as these can provide a model for others to follow. Knowledge transfer that brings the benefits of research from the laboratory to the farm is essential.

Programmes targeted at vulnerable groups such as women and tribal communities are particularly important. IFAD-supported programmes and projects in India promote tribal development by building and strengthening grassroots institutions that enable vulnerable people to plan and manage their own development, negotiate improved entitlements, and broaden their livelihood opportunities. Conferences and talks among world leaders can do many things but they don’t feed people. We hope that leaders will keep in mind those who do: the smallholder farmers. Price volatility and the persistence of widespread, endemic and hidden hunger underline the need for urgent attention to enhancing the productivity and profitability of smallholder agriculture in an environmentally sustainable manner. This is the pathway to increasing agriculture’s contribution to climate change mitigation as well as to sustainable food security.

(Prof. M.S. Swaminathan is Member of Parliament, Rajya Sabha, and Chairman, M.S. Swaminathan Research Foundation. Kanayo F. Nwanze is President, International Fund for Agricultural Development, a U.N. agency and international financial institution dedicated to helping poor, rural people overcome poverty.)

A visit to Subhash Sharma’s organic farm, Chhoti Gujri, Yavatmal, Maharashtra

 (Source: India Water Portal)

This presentation by Sultan Ismail, deals with the experiences of Subhash Sharma of Yavatmal, Maharashtra in organic farming. As he watched the decline of his soil and agricultural yields he let nature be his teacher and tried to understand the agro-economics of agriculture. He abandoned insecticides and chemical fertilisers and relied instead on the cow, trees, birds and vegetation with remarkable results. Click: Economics of agriculture under natural farming – Research paper – Subhash Sharma – Yeotmal – OFAI SAC (2009) 62.29 KB)

Community Managed Sustainable Agriculture-Interview with Raidu DV

The Andhra Pradesh agriculture department has decided to join hands with the rural development ministry’s Society for Elimination of Rural Poverty (SERP) to take the Community Managed Sustainable Agriculture (CMSA)  programme forward. This ushers in good news as it indicates the acceptance of chemical free agriculture by the agriculture department, which is usually known to back chemicals in the name of productivity.DV Raidu, Director, Community Managed Sustainable Agriculture (CMSA) in an interview with Savvy Soumya Misra talks about the success of the programme and its future  with the agriculture ministry.


How do you see the partnership with agriculture department panning out in promoting sustainable agriculture in the state?

With this partnership, we will be looking to build on each other’s strengths. The community based character of the program through decentralized extension model will converge with technical strength of Agriculture Technology Management Agency (ATMA) and take Integrated Pest Management (IPM) and Integrated Nutrient Management (INM) to its logical conclusion. We start working at farm (household) economy comprehensively in addition to production and productivity. Further SERP’s efforts in trying to find out “end to end” solution by integrating dairy, poultry and small ruminants will be a big strength. Already we are working in convergence with the animal husbandry department in a small way; this will further strengthen our programme.

 

What do you envisage will be the role of the agriculture ministry in the scheme of things?

The ministry of agriculture will bring in the latest technology that will help farmers’ to reduce dependency on external inputs and help them revisit their own traditional wisdom. They will help communities to better implements like neem pulverizer, power weeder, small transplanters, small harvesters to reduce drudgery and improve efficiency of workforce. The ministry of agriculture would facilitate work on empowering farmers by mobilizing them into ‘joint liability groups’ (JLG) or ‘producer companies’. These farmers’ organizations will play critical role in accessing credit, improving marketing facilities and deciding markets for better prices.


How has CMSA changed agriculture in Andhra Pradesh since 2004?

Currently the programme is being implemented in 8033 villages of 503 mandals across 22 districts with 10.47 lakh farmers and 27.05 lakh acres. The emphasis of CMSA has been on reducing the cost of cultivation through non pesticide management (NPM) methods, restoring ecological balance, promoting green manure and dung based inoculants. The emphasis is on reduced dependency on external inputs and using locally available resources and this has improved the profitability of farmers. By preserving beneficial insects we are able to withdraw chemical pesticides. A survey followed by a third party assessment in 2008 showed a 70-80 per cent reduction in cost of pest management and 50 per cent reduction in fertilizer cost. The number of cases of hospitalization due to pesticide poisoning has also reduced. There is growing demand for this kind of agriculture.


Talking of pesticide poisoning, pesticides are also associated with a lot of health problems. Has there been an improvement in health after shifting to NPM?

In areas where NPM is practiced, cases of acute toxicity due to spraying of pesticides have completely gone away. It has also benefited those who weed chili fields, the leaves of which were always covered with pesticides and were prone to skin and breathing ailments. NPM has improved the quality and freshness of vegetables. In our interaction with women, we learn that their health has improved. We need to study the health impacts of the agricultural interventions. There is a plan to do such a study with organizations like IFPRI and the rural development ministry at the centre.


How difficult was it to get farmers to shift from the conventional agriculture to non pesticide management of farming?

Initially it was difficult. They were unsure how pests that were not being killed with powerful pesticides could be killed with botanicals. But they were keen on getting rid of chemicals. They were explained how the life cycle of pest should be observed and non chemical methods like summer ploughing and other nine practices called non-negotiables would be adopted for pest control. They were told about the importance of family labour in monitoring fields and pests. Farmers were encouraged to try NPM farming on a quarter of an acre initially and compare it with the other area for the entire season. It was a slow but a steady process.


What are the key inputs of Non Pesticide Management farming technique?

Locally available natural resources are the inputs for NPM. The only exception is pheromone trap which can be purchased. Communities identified 108 plants from which extracts could be made for controlling pests. The thumb rule is that any leaf which is not eaten by goat or sheep can be used for preparation of botanical extracts. The most prominent inputs are plants like neem, vitex, lantana, dathura and cow dung and cow urine. Moreover, farmer’s knowledge is the basic input here. Harvesting sun light by covering land in several tiers is key to raise productivity and incomes. The technology promoted under Integrated Pest Management (IPM), is followed here also without the option of chemicals as last resort. The availability of community based platform in AP facilitates the decentralized extension in transmission of technology.

 

CMSA now plans to convert to organic farming. What are the key changes you would bring in to convert to organic farming?

The key element in moving towards organic farming is to bring life back into the soil. And this can be done by using animal dung and urine which will help increase the microbial content of the soil by proliferating native earthworms. Rainwater harvesting has to be encouraged. The farmer has to be trained to shift from mono-cropping to poly-cropping with special emphasis on legumes except perhaps paddy. As leaves are integral to composting and compost is integral to NPM, so trees have become the focus of farming now. Leaves contain 85 per cent of the nutrients removed from the soil. The CMSA model has identified farmers to take this to its logical end. We are overlaying the Participatory Guarantee System (PGS) with the help of the National Centre of Organic farming (NCOF). But the important point is to ensure that there is no reduction of yield and there is access to market premiums for pesticide free produce. It has happened in case of chillies in Guntur, where farmers have produced pesticide free chillies and exported to European markets with a premium of Rs.1800/- per quintal. Some farmers are migrating to organic farming.


Organic cultivation or Non Pesticide Management (NPM) method both are very labour intensive. With more and more people moving out of agriculture, especially the younger generation, do you think that a labour intensive farming method like organic cultivation or NPM is something farmers that would go for?

Organic or CMSA methods are most relevant to small and marginal farmers who are 80 per cent in number and area. Most of the times they are underemployed. With the popularization of ½ acre model under irrigated conditions the farmer’s family is gainfully engaged for 365 days. We have also noticed that a good number of farmers, especially women farmers, are young and they feel excited that they have control on the inputs and processes. These young women bring to the field traditional wisdom. So more and more people are getting attracted towards farming.


CMSA works on the concept of Self Help Groups. Is there a chance that there could be a certain section of the society (class or caste) that could be excluded due to any reason?

It’s an inclusive model. Self Help Groups comprise of four categories of rural house holds- poorest of the poor, poor, not so poor, Above Poverty Line. Further special efforts are made to rope in poorest of the poor women i.e Scheduled Caste /Scheduled Tribes and others who don’t have enough money for monthly savings. Government is supporting –initially to help contributing to their savings. Big farmers in the village are also included in the program. The groups work on two broad categories- one with farmers from SHG’s and the others outside of the SHG’s which also includes poor outside the fold of the self help groups. Thus there are no chances for exclusion of certain sections of farmers.

 

Have other states approached CMSA for promotion in their states?

They are now approaching us through the ministry of rural development at the centre. For some time we couldn’t take the offer in view of our own heavy engagement in the state; now we are willing to offer services of two to three experts for five days a month basis.

 

How much can one profit by converting to NPM?

At present, our experience shows, that farmers earn a profit of about Rs 2000- Rs 4000 per acre. There is substantial scope for further enhancement of profits if the farmer implements Rain Fed Sustainable Agriculture model and half acre model in mission mode.

 

It is always contested by agriculture department that organic cultivation and chemical free agriculture cannot be the solution to the country’s food security problem. Do you agree with this notion that our policy makers have at the centre?

No, we don’t agree. What we are practicing is basically Integrated Pest Management (IPM) and Integrated Nutrition Management (INM) approved by the Indian Council of Agricultural Research. Regarding IPM, we are clear about withdrawing pesticides immediately. About INM, it is a gradual reduction of chemical fertilizer, simultaneously replacing with leaf based organic manure with dung as inoculant. For example, urea will be replaced gradually with azolla in paddy. Subsoil nutrients are recycled through tree based farming and leaves going back to soil. We should not get bogged down by calling it organic farming; this is ‘sustainable agriculture’. Chemicals will get reduced gradually; maintaining or improving the present yield levels, hence food security is not compromised.


 

Baba Ramdev demands a shift to Sustainable Agriculture

Swami Baba Ramdev is calling a fast from 4th June onwards against Corruption and Black Money Hoarding.  Sustainable Agriculture and related matters are in his major demands ( in his main letter to the Prime Minister).  Today, Swami, Acharya Balakrishna and Devinder Sharma along with others in his team was invited for a discussion with Cabinet ministers led by Pranab Mukherjee.  Kapil Sibal, Pawan Bansal and Subhodh Kant sahai and the Cabinet Secretary was also there for the discussion.  Today Swamiji’s team presented the demands.  Devinder presented the demands on agriculture.  The following are broadly the demands on agriculture

Land Acquistion

1. No Agriculture Land should be acquired for non-agri purposes
2. No Land should be acquired without the permission of the Grama Sabhas

GM and Seeds
3. A 10-year moratorium on Bt-Brinjal and all field trials and commercial release of all GM crops
4. Price regulation on Seeds
5. Every district to have a Community Controlled Seed Centre with a gene bank for traditional seeds

6. Liability in case of contamination of non-GM crops

7. BRAI Bill to be jointly drafted in consultation with civil society
8. Ban on import of all GM food products and allow imports only if they carry a GM free label

 

Pesticides
6. A ban on all the 67 pesticides that have been banned in other countries but still used in India.

Sustainable Agriculture
7. 12th Five Year Plan to have 25% of total agriculture area brought under Non-Pesticidal Management as in the CMSA in Andhra Pradesh (the NPM has been repeated in 3 places in the demand annexes)
8. A Land Conservation fund for farmers to the tune of Rs. 5000 crore to be allocated each year

Other farmers issues
9. A Farmers Income Commission to be setup and income guaranteed to the farmer through a Farmers Income Guarantee Act (FIGA)
10. MSP to incorporate the farmers contribution as a Skilled Labour and not as General Labour and the MSP be calculated after fixing at 50% higher that the C2 Cost.
11. 24-hr water and electricity supply to be given to farmers
12. Community grain banks in every panchayath

Education in the Agriculture, Health and Engineering Sectors to be in Hindi and other State languages.

Report of Special Rapporteur on the Right to Food, Olivier De Schutter

Download the report

The reinvestment in agriculture, triggered by the 2008 food price crisis, is essential to the concrete realization of the right to food. However, in a context of ecological, food and energy crises, the most pressing issue regarding reinvestment is not how much, but how. This report explores how States can and must achieve a reorientation of their agricultural systems towards modes of production that are highly productive, highly sustainable and that contribute to the progressive realization of the human right to adequate food. Drawing on an extensive review of the scientific literature published in the last five years, the Special Rapporteur identifies agroecology as a mode of agricultural development which not only shows strong conceptual connections with the right to food, but has proven results for fast progress in the concretization of this human right for many vulnerable groups in various countries and environments. Moreover, agroecology delivers advantages that are complementary to better known conventional approaches such as breeding highyielding varieties. And it strongly contributes to the broader economic development. The report argues that the scaling up of  these experiences is the main challenge today. Appropriate public policies can create an enabling environment for such sustainable modes of production. These policies include prioritizing the procurement of public goods in public spending rather than solely providing input subsidies; investing in knowledge by reinvesting in agricultural research and extension services; investing in forms of social organization that encourage partnerships, including farmer field schools and farmers’ movements innovation networks; investing in agricultural research and extension systems; empowering women; and creating a macro-economic enabling environment, including connecting sustainable farms to fair markets.

Organic farming – India’s future perfect?

Nishika Patel

A budding interest in organic food offers farmers soaring incomes and higher yields, but critics say it’s not the answer to India’s fast-rising food demands

MDG : Organic farming in India

An Indian farm labourer displays a cabbage grown on an organic farm in India’s Gujarat state. Photograph: Sam Panthaky/AFP/Getty Images

India’s struggling farmers are starting to profit from a budding interest in organic living. Not only are the incomes of organic farmers soaring – by 30% to 200%, according to organic experts – but their yields are rising as the pesticide-poisoned land is repaired through natural farming methods.

Organic farming only took off in the country about seven years ago. Farmers are turning back to traditional farming methods for a number of reasons.

First, there’s a 10% to 20% premium to be earned by selling organic products abroad and in India’s increasingly affluent cities, a move towards healthy living and growing concern over toxic foods and adulteration plaguing the food market.

Second, the cost of pesticides and fertilisers has shot up and the loans farmers need to buy expensive, modified seed varieties are pushing many into a spiral of debt. Crippling debt and the burden of loans are trriggering farmer suicides across the country, particularly in the Vidarabha region of Maharashtra. Organic farming slashes cultivation and input costs by up to 70% due to the use of cheaper, natural products like manure instead of chemicals and fertilisers.

Third, farmers are suffering from the damaging effects of India’s green revolution, which ushered in the rampant use of pesticides and fertilisers from the 1960s to ensure bumper yields and curb famine and food shortages. Over the decades, the chemicals have taken a toll on the land and yields are plunging.

“Western, modern farming has spoiled agriculture in the country. An overuse of chemicals has made land acidic and hard, which means it needs even more water to produce, which is costly,” says Narendra Singh of Organic India. “Chemicals have killed the biggest civilisation in agriculture – earthworms, which produce the best soil for growth.”

Umesh Vishwanath Chaudhari, 35, a farmer in the Jalgaon district in Maharashtra, switched to organic farming seven years ago after experiencing diminishing yields from his 8-hectare (20-acre) plot. He came across a book on organic farming techniques using ancient Vedic science. He started making natural fertilisers and pesticides using ingredients such as cow manure, cow urine, honey and through vermicomposting – the process of using earthworms to generate compost. Since then, his yields and income have risen by 40%, and worms have returned to his soil. He sells lime, custard apple and drumsticks to organic stores in Pune, Mumbai and other cities, while his cotton is bought by Morarka, a rural NGO.

He plans to convert another 2 hectares to organic cotton and buy 10 cows to make his own manure, rather than buying it. “Using manure instead of pesticides and fertilisers has cut my costs by half, and I get a premium on these goods,” he says. “I used to drive a scooter, but in the past few years I’ve been able to afford a bike and car – and even two tractors.”

Udday Dattatraya Patil, 43, an agriculture graduate, turned to organic farming after his crops were showing a deficiency in feed, leading to rising fertiliser costs. In addition, his banana crop was being wrecked by temperature fluctuations and climate change. “Because bananas are sensitive to temperature change, 20% went to waste. Organic bananas can withstand this. Now none are wasted,” he says. Now he has 40 cows and bulls whose manure he can use for fertiliser, as well as vermicompost units. His yields have increased by 20% and income by 30%.

Although he is hailed as a progressive agriculturalist by his fellow villagers, he is the only organic farmer out 3,000 in Chahardi, in Jalgaon district. “Some have tried but they give up if there aren’t immediate results. Organic farming requires effort, and you have to invest in organic inputs,” he adds.

Many farmers are reluctant to make the leap because they fear a drop in yields in the initial period; good results tend to show after three years. Moreover, the market is growing by 500% to 1,000% a year, according to Morarka, but it only represents 0.1% of the food market.

Kavita Mukhi organises a weekly organic farmers’ market in Mumbai, where producers sell direct to consumers. She is trying to boost awareness about organic food. “The only way you hear about it is if you stumble on an organic shop,” she says. “There’s no widespread marketing or awareness of the benefits.”

Once the awareness increases, organic agriculturalists believe more farmers will join the movement because it’s favourable to small farmers. They already have the cows and buffalos needed to recycle biomass at the farm level, which is, essentially, the foundation of organic farming.

“Unlike Europe, India’s modern farming revolution is not very old, meaning they still possess the knowhow for cultivation without modern chemical inputs,” says Mukesh Gupta of Morarka.

While critics argue that organic farming is not the answer to India’s rising food demands, those in favour say it’s the only sustainable way out for impoverished farmers

Organic farming can feed the world, U-M study shows

ANN ARBOR, Mich.—Organic farming can yield up to three times as much food on individual farms in developing countries, as low-intensive methods on the same land—according to new findings which refute the long-standing claim that organic farming methods cannot produce enough food to feed the global population.

Researchers from the University of Michigan found that in developed countries, yields were almost equal on organic and conventional farms. In developing countries, food production could double or triple using organic methods, said Ivette Perfecto, professor at U-M’s School of Natural Resources and Environment, and one the study’s principal investigators. Catherine Badgley, research scientist in the Museum of Paleontology, is a co-author of the paper along with several current and former graduate and undergraduate students from U-M.

“My hope is that we can finally put a nail in the coffin of the idea that you can’t produce enough food through organic agriculture,” Perfecto said.

In addition to equal or greater yields, the authors found that those yields could be accomplished using existing quantities of organic fertilizers, without putting more farmland into production.

The idea to undertake an exhaustive review of existing data about yields and nitrogen availability was fueled in a roundabout way, when Perfecto and Badgley were teaching a class about the global food system and visiting farms in Southern Michigan.

“We were struck by how much food the organic farmers would produce,” Perfecto said. The researchers set about compiling data from published literature to investigate the two chief objections to organic farming: low yields and lack of organically acceptable nitrogen sources.

Their findings refute those key arguments, Perfecto said, and confirm that organic farming is less environmentally harmful yet can potentially produce more than enough food. This is especially good news for developing countries, where it’s sometimes impossible to deliver food from outside, so farmers must supply their own. Yields in developing countries could increase dramatically by switching to organic farming, Perfecto said.

While that seems counterintuitive, it makes sense because in developing countries, many farmers still do not have the access to the expensive fertilizers and pesticides that farmers use in developed countries to produce those high yields, she said.

After comparing yields of organic and non-organic farms, the researchers looked at nitrogen availability. To do so, they multiplied the current farm land area by the average amount of nitrogen available for production crops if so-called “green manures” were planted between growing seasons. Green manures are cover crops which are plowed into the soil to provide natural soil amendments. They found that planting green manures between growing seasons provided enough nitrogen to replace synthetic fertilizers.

Organic farming is important because conventional agriculture—which involves high-yielding plants, mechanized tillage, synthetic fertilizers and biocides—is so detrimental to the environment, Perfecto said. For instance, fertilizer runoff from conventional agriculture is the chief culprit in creating dead zones—low oxygen areas where marine life cannot survive. Proponents of organic farming argue that conventional farming also causes soil erosion, greenhouse gas emission, increased pest resistance and loss of biodiversity.

For their analysis, researchers defined the term organic as: practices referred to as sustainable or ecological; that utilize non-synthetic nutrient cycling processes; that exclude or rarely use synthetic pesticides; and sustain or regenerate the soil quality.

Perfecto said the idea that people would go hungry if farming went organic is “ridiculous.”

“Corporate interest in agriculture and the way agriculture research has been conducted in land grant institutions, with a lot of influence by the chemical companies and pesticide companies as well as fertilizer companies—all have been playing an important role in convincing the public that you need to have these inputs to produce food,” she said.

Organic agriculture and the global food supply
Catherine Badgley,Jeremy Moghtader,Eileen Quintero,Emily Zakem,M. Jahi Chappell,Katia Avilés-Vázquez,Andrea Samulon and Ivette Perfecto (2007).

Renewable Agriculture and Food Systems, Volume 22,
Issue 02, June 2007 pp 86-108

http://journals.cambridge.org/action/displayAbstract?aid=1091304