Systems of Rice Intensification

Environmental Benefits and Economic Feasibility

Environmental Strategies Natural Resources 431 October 25th 2004 Sinon Bamidaaye Nora Lovell Grant MacIntyre Paswell Marenya Jong O Sun Isaiah Sutton

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Table of Contents

Introduction …………………………………………………………………… 3

Sustainable Agriculture …………………………………………………….4 Sustainable Agriculture and Natural Resource Management …………….7 Principles and Practices: SRI Nuts and Bolts …………………………….8

Seed Selection Site Preparation Transplanting Water Use Harvest Economic Tools for Water Management in Irrigated Agriculture ……………12

Salinity and water logging Ground Water Depletion Chilean Water Management Case Study Conventional Rice Cultivation ……………………………………………19 Soil Chemistry ……………………………………………………………21 Labor Intensification ……………………………………………………………25 Labor Intensification and the Feasibility of SRI ……………………………31 Conclusive Recommendations and Solutions ……………………………………33 Works Cited ……………………………………………………………………36

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Introduction

Can Systems of Rice Intensification (SRI) translate into economic and ecological

profits for farmers in developing nations? SRI is a suite of management methods that

raise factor productivity of land, labor and capital. Research has demonstrated that SRI is

model of sustainable agriculture that results in reduced inputs, conserved water, improved

soil structure and increased yields. These factors synergistically interact to provide

farmers with increased net profits. There are significant obstacles that need to be

overcome in order for the monetary and environmental benefits to be recognized. The

labor intensification required to implement SRI makes the adaptation to this system

unfeasible for cash constrained rice cultivators.

As more and more areas of the world start to develop they utilize more and more

of the resources around them. This is the same crash course that developing countries are

just starting to pull out of and developing countries don’t need to go down that same path.

In developing countries local residents rely on, and often exploit, the surrounding

environmental resources in order to meet basic needs. These are traditionally people that

have deep and reverent respect for the land but often have little choice when deciding

between sustenance and environmental degradation.

New more efficient methods in agriculture, forestry, and all industry have the

potential to make the growing pains of the developing world less painful on the

environment and the people of these regions. SRI is a promising example of one of these

new methods. By introducing developing countries to new methods of production they

can increase profitability, and quality of life while decreasing environmental degradation.

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Sustainable Agriculture The numbers of poor, landless and hungry people in the world are increasing

despite the achievements of the last forty years. Most of these people live in rural areas

where they depend on farming, forestry, fisheries, and related rural industries on which

the present generation depends for food, employment and incomes. It is also these

resources they hope to bequeath to future generations. Of the 1.2 billion people

worldwide who earn a dollar a day or less, 75 percent work and live in rural areas;

projections suggest that over 60 percent will continue to do so in 2025.

Hardin (1993) noted that means of achieving a better tomorrow for the world’s poor

people and sustaining the productivity of natural resources cannot be considered

separately one from the other. Rapid population growth, grinding poverty, low

agricultural productivity, urban-biased governments have created a situation that

inevitably leads to natural resource degradation in developing countries. It is easy to

appreciate why rural poor attempting to cope under such circumstances, rank concerns

about long-term investments in resource conservation lower than meeting current survival

needs. The result is often unsustainable if not irreversible exploitation of fragile

ecosystems.

Earlier paradigms of agricultural development promoted the general view that

plenty of fertilizers, irrigation water, pesticides and herbicides, combined with high-

yielding varieties of a few crops, and mechanization would spur broad-based agricultural

and economic progress. However, evidence shows that these industrialized technologies

may also lead to serious environmental degradation. The challenge today is to find ways

of producing higher yields of crops and livestock while conserving the essential natural

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resources, like soils, water, forests and biodiversity that will be needed for the survival of

future generations. Solutions to environmental problems require awareness, knowledge

and resources, together with a societal motivation to find and implement innovative

advances (Jyoti and Kirit 2000).

Murdoch (1980) observed that development inevitably brings in its train the

disruption and loss of natural ecosystems and of hundreds of thousands of species of

plants and animals. To the ecologists, these losses of flora and fauna are tragedies. For

the global community in general there is also the problem that any species lost may

contain genetic information that might be of use to us in the future. Some analysts argue

that economic growth must be sacrificed even in poverty stricken areas, if that means

protecting the natural environment. But preventing economic growth is not a real option,

even if it were possible. Inexorable increase in human population is the greatest ultimate

threat to nature, and economic development is the only force that can stop environmental

disaster. Without rural development, in particular, the poverty-stricken agrarian

populations of the world will continue to expand onto and to destroy those wild

ecosystems that still exist. By contrast, rural development based largely on intensive

farming, can restrict movement onto marginal land providing the agrarian population

with the means to manage the land properly. It would thus help save natural

environments.

However sustainable agricultural intensification requires that the quality of soils

and non-agricultural environment either remain constant or improve and limited natural

resources (such as water and mineral fertilizer) are not overexploited. There are two

views on how this sustainable agriculture might look. In what Penning et al (1995) call

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an ecotechnology-oriented approach, sustainable agriculture resembles is an ‘integrated’

system of farm production akin to Western European agriculture, but one in which the

emerging shortcomings are minimized.

Providing what seems as an alternative view to the poverty-agriculture-environmental

degradation linkage, Paarlberg (1993) argued that poor farmers in developing countries

are assumed to abuse their own soil and water resources because they are living from

hand to mouth, their discount on the future being too high. They cannot afford to wait for

trees to mature, so they do not adopt agroforestry. They cannot afford to wait for

rangelands to recover, so they continue to overgraze. They cannot afford to wait for

investments in terracing to pay off, so they continue to plough up hillsides. Paarlberg

however asserts that despite these arguments poverty alone is a poor predictor of

agricultural resource degradation, just as wealth alone is a poor predictor of resource

protection.

The review in this section has captured certain common threads that run through

the literature on environment, development and poverty in developing regions of the

world. The major environmental concerns in developing lands revolve around poverty-

driven degradation of farmlands, communal pastures, as well as forests and water

catchments. This is compounded by institutional deficiencies that fail to define and

enforce property rights for the masses of smallholders who are expected to make long

term investments in maintaining the productivity of natural resources. Lack of

appropriate economic incentives also stand in the way of investments in long term natural

resource management and intensification especially for the masses of impoverished

smallholder producers.

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Natural Resources Management and Sustainable Agriculture

University of California Berkeley professor Miguel Altieri explores the

opportunities and limitations of agroecological approaches to spur agricultural

productivity throughout the developing world. He says that resource-poor farmers (about

1.4 billion people) located in risk prone, marginal environments, remain untouched by

modern agricultural technology. A new approach to Natural Resource Management must

be developed so that new management systems can be tailored and adapted in a site-

specific way to highly variable and diverse farm conditions typical of resource-poor

farmers. Agroecology provides the scientific basis to address the creation of self

fuctioning of diverse agroecosystems. At the heart of the agro ecology strategy is the

idea that an agroecosystem should mimic the functioning of local ecosystems thus

exhibiting tight nutrient cycling, complex structure, and enhanced biodiversity. The

expectation is that such agricultural mimics, like their natural models, can be productive,

pest resistant and conservative of nutrients

This case is made strongly by Conway (2001) who confirms that technological

advancements in agriculture are indispensable for what is now called the doubly green

revolution. This involves the use of biotechnology and modern principles of ecology as

the basis for launching what might be called a second generation technological revolution

in Agriculture that could be aimed at the hitherto underdeveloped and poor agricultural

systems. Areas in which the green revolution technologies have gained a foothold will

have their sustainability ensured with this revolution. This is especially so in view of

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evidence now emerging that there is a slow down in yield gains in areas where green

revolution has taken place partly due to negative environmental outcomes inherent in the

green revolution technologies themselves but also precipitated by inappropriate policy

and institutional conditions (Pingali and Rosengrat 2001).

Principles and Practices

SRI Nuts and Bolts SRI is a suit of management techniques that drastically change traditional

methods of rice agriculture. It is a system of careful management and precise timing. The

methods focus primarily on the factors of rice production; the rice plant, the soil, and the

water regime. The system attempts to realign cultivation methods to lie closer with the

ecological aspects of the rice plant, and in doing so improve soil, water and overall

environmental quality. According to Rabenandrasana, the success of this system is

directly related to the “synergetic development of both the tillers and roots.” This synergy

strives to maximize root production and health which is directly related to tiller

production (Uphoff 2002). These new methods … “are not a technologies but

recommended changes in management practices.” (Uphoff 2004). It is for this reason that

the system is not a concrete set of instructions but rather individual techniques. Each of

these techniques on its own can improve an existing system but create maximum

effectiveness together.

Seed Selection

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The SRI methods recommend starting at the beginning with seed selection. SRI

recommends that a farmer first separate the bad seeds from the good ones. This task is

completed by floating the seeds in a saline solution. The seeds that are no good will float

and the good seeds will separate out and fall to the bottom (ADRA). This will ensure that

only the seeds most likely to germinate will be sown into the nursery. The nursery beds in

the SRI system are very similar to traditional beds. They should be dry site at the high

spot of the property, accessible to water as needed. The most notable exception is that the

seeds are sown at wider spacing and cover generously with compost (ARDA). Wider

spacing aids in easier, gentler transplanting and better growth.

Site Preparation

Fields are prepared at the same time of year, in similar conditions, and with the

same tools as traditionally. The fields are still plowed and raked traditionally; the major

differences are the grid system that is imposed onto the field, the compost that is applied

and the drainage netwoks required. SRI strongly recommends wide plant spacing so grids

that are raked onto the field should be squares that are between 25 and 30cm on each

side. (Koma 2004)(ARDA).These wide grid patterns will decrease competition between

plants. While this system along with single transplants (see following) will decrease the

over all number of plants but the fewer plants will be substantially healthier and more

productive. (Uphoff 2004). SRI also recommends the abandonment of chemical fertilizer

and a shift to organic compost. This can be weed crops on fallow fields or even livestock

manure (Uphoff 2004)(ADRA). This will help maintain nutrient levels in the soils. This

is essential because with increased plant vigor comes with increased nutrient use

(Association Tefy Saina).

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Transplanting One big shift from traditional methods is the age of seedlings at the time of

transplantation. They recommend transplanting seedlings 8-10 days old rather than the

traditional 20-30 day old transplants (Berkelaar 2001). Earlier transplanting induces the

shock of transplant at a more convenient point in the growth cycle when they can

rebound faster and have little effect on tillerage (Uphoff 2002). The young seedlings are

to be transplanted with in 15 minutes of removal from the nursery to minimize shock

(Association Tefy Saina). This is done gently assuring that the seed sacs are not damaged

(ADRA)(Koma 2004). The seedlings are then gently pushed into the prepared field

individually (Uphoff 2002) (All SRI Readings). Singular planting is one of the biggest

leaps from traditional methods see figure 2 for a comparison of the two. By planting

seedlings close together none thrive and some die (Association Tefy Saina). This is a

waste of time, energy and resources. Using the SRI system can at least save seed costs by

producing an equal amount of rice with half the seed density (Thiyagarajan). With careful

transplanting seedling mortality is very low.

Figure 2. SRI seedlings (at left) are very widely spaced compared to seedlings planted with traditional methods (at right).These diagrams show seedlings at approximately one month of age, when seedlings are

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roughly the same size. However, SRI seedlings, having been transplanted several weeks earlier, by this time have already undergone transplant shock and may have begun to tiller. Sketches by Christi Sobel. (Berkelaar 2001) Water Use

Another significant shift from traditional methods of rice cultivation called for by

SRI is in water use and efficiency. The optimum soil conditions for rice cultivation is

moist but well drained soil. With SRI, fields are not flooded during the plants' vegetative

growth and never flooded for more then 4 days at a time. (Uphoff 2002)(Uphoff 2001).

The method of flooding is effective at weed control, but it also limits the growth potential

for the plant. Flooding causes hypoxic conditions in the soil this prevents the plants’ roots

form receiving necessary nutrients that are brought into the soil through aeration

(ADRA). It has been found that in flooded conditions rice plants may lose as much ¾ of

their root mass by the time they flower (Berkelaar 2001). The soil is kept moist most of

the time with periodic application of water to keep soil moist. The fields are allowed to

dry out, some times to the point of cracking, to allow for surface aeration. (Association

Tefy Saina) Allowing for roots to exchange gases with the atmosphere is essential to the

SRI objective increasing root growth. The SRI method of carefully applied water shows a

win-win relation ship between plant production and net water consumption. This method

does however require a significant increase in labor. By not flooding the fields and

applying water at opportune stages of plant growth farmers can realize 25-30 % water

savings (Gupta 2002). In order to change the water application methods of rice

agriculture farmers must also change their water management regimes. Fairly intricate

systems must be implemented to allow for timely irrigation and easy removal of water

from fields. This is done through various dams, dikes, ditches, levees and lagoons

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(ADRA). The implementation of these systems is intricate and time consuming, requiring

a large amount of labor.

Harvest

Harvest methods under the SRI methods are basically the same as traditional

methods. The main difference is the increased labor required for harvest. This is not a

function of a change in systems but more a function of increased yields (Association Tefy

Saina).

Economic Tools for Water Management in Irrigated Agriculture

Agriculture, especially irrigated agriculture constitutes a major user of water in

the world. Over the next 20 years the average supply of water worldwide per person is

expected to drop by a third according to a UNESCO report. This proves the need for

water conservation. The environmental consequences of excessive use of water in

irrigated agriculture especially in Asia have been documented by Pingali and Rosegrant.

(2001) While these authors recognize that the green revolution technologies contributed

immensely to food production and alleviating food scarcities in Asia, they also show that

these enormous successes in the rice and rice-wheat systems in South and South East

Asia have experienced recent obstacles. Growth in cereal yields has leveled off

especially in the irrigated lowlands of Asia and there are indications of sustained declines

in the future. This is partly due to international declines in cereal prices but also due to

deleterious ecological consequences of the intensified irrigated rice production systems

of Asia.

Lowland, agricultural intensification has serious environmental consequences.

The buildup of water salinity, the depletion and pollution of groundwater resources, soil

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compaction, changes in soil nutrient status, nutrient deficiencies and increased incidence

of soil toxicities, pest immunization to pesticides, injudicious use of agrochemicals and

the related yield losses. The environmental impact of primary concern in this paper is

salinity/water logging and depletion of water resources. The focus is not to say anything

about the relative importance of the problems listed above but to provide a focal point for

analyzing the potentialities for SRI to forestall or alleviate excessive water use depletion

of water resources in irrigation-dependent agriculture. In any case doing justice to all

these issues is clearly beyond the scope of this paper.

Salinity and water logging

Intensive use of irrigation water in areas of poor drainage can lead to hydrological

problems, namely a rise in the water table due to continual recharge of the of the ground

water. In humid areas this leads to salinity build up and in humid areas it leads to water

logging. At the root of these problems is the inefficiency of irrigation water use. An

essential component of improving water use efficiency would be pricing irrigation water

at its true cost.

Groundwater depletion

In Bangladesh, India and Pakistan the private agricultural sector has caused a

massive expansion in tube well irrigation use. These developments have stimulated rapid

agricultural growth with nearly 1.5Mha of land coming into irrigation in the 1980s as a

result. However, just as excess use of unpriced irrigation water can lead to rising water

tables and salinization it can also lead to falling water tables in tube well irrigated areas,

with negative environmental and productivity consequences.

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The main cause of excessive drawing of water in irrigated systems is that the

overdrawing of groundwater often occurs because individual pump operators have no

incentive to optimize long run extraction rates since water left in the ground can be

captured by other users, other irrigators or potential future irrigators. The

depletion therefore proceeds apace because extraction exceeds natural recharge rates. In

parts of China groundwater levels are falling by as much as 1m/year. Government

intervention to redress the depletion of groundwater has proved both difficult, due to

many dispersed operators. Even China with a strict legal system has been unable to avoid

massive overdrawing. Pingali and Rosegrant therefore suggest that governments should

move toward incentive based systems to effectively manage groundwater resources and

reduce the negative impacts and fostering the appropriate use of valuable groundwater

resources.

These problems are consequences of market failures and much the same way

other environmental conditions are caused by market failures. Other institutional failures

also exacerbate these conditions. Since irrigated water is supplied at below social costs,

the attendant overuse and externalization of costs associated with it are the direct result of

lack of appropriate market and or economic mechanisms for water pricing. Yet water as a

natural resource is increasingly scarce. Its use in any economic activity must recognize

this scarcity.

While acknowledging the institutional difficulties of monitoring water allocation

in systems characterized by many users and hence the difficulty in cost charging

appropriately for water use, the establishment of economic incentives and institutional

innovations that revolve around local management of water resources are suggested. The

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paper by Pingali and Rosegrant conclude that the implementation of tradable water rights

may represent a long term solution to water problems in irrigation systems in much of the

developing world. The Chilean example described below demonstrates a successful

implementation of a tradable water rights system.

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Box 1Tradable Water Rights: A Chilean Example

Chile introduced in 1981 an elaborate legal and institutional mechanism for the allocation of water

rights. In Chilean law water is considered a public good, but individuals can obtain private rights over

water by receiving a grant from the State for new water sources, by prescription or by purchasing water

rights. The Chilean constitution passed in 1980 (and amended in 1988) provides that ‘The rights of

private individuals, or enterprises, over water, recognized or established by law grant their holders

property over them. These rights can be consumptive or non consumptive. Non-consumptive rights (eg

hydropower generation) do not limit consumptive rights over the same water. Water use according to

the law must not limit the rights of third parties over the same water in terms of quality, quantity and

access.

Before these institutional innovations water services were provided by state owned entities which were

highly subsidized and inefficient. Those who received the water received it cheap due to the subsidies

and market solutions were intractable political issues. After the reforms active water markets have

developed in several regions both within agriculture and between agriculture and other sectors.

Transactions between farmers involve water swaps for those farmers with different requirements during

different seasons. Other farmers employ drip irrigation and sell the water to finance the investment.

One of the most important innovations of Chile’s water policy is that it allows cities to buy water

without having to buy the land or expropriate water. Growing cities now can buy rights from many

farmers, usually buying a small portion of each farmers total rights. It is reported that there have been

rare cases of negative effects in agricultural zones neighboring water demanding urban areas because

farmers mostly sell small portions of their rights and maintain agricultural production with highly

efficient irrigation technology. Farmers obtain important infusion of fresh capital in exchange for their

water rights. A farmer who increases irrigation efficiency by 30% on a 40ha farm can dispose of water

rights shares equivalent to 24l/sec, selling for $7000-$10000 without reducing agricultural production.

(Source: Material adapted from Schleyer and Rosegrant 1996)

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The Chilean example in Box1 proves the feasibility of water use management.

The principles and practices of SRI enable market actors to realize the economic,

environmental and agricultural benefits of water use management. The Chilean case

study provides a relevant example of the feasibility and necessity of water use

management. The Chilean examples illustrates how powerful appropriate institutions

mechanisms combined with economic incentives can be in solving water use issues. Such

systems are critical in designing economic incentives for water management. For instance

if farmers have tradable water quarters, then agronomic systems that help them save on

water means that the saved water is an economic asset. This asset can be traded over the

open markets and thus generate incomes. This provides powerful economic incentives for

saving on the available water. The Chilean example has shown that the institutional and

management difficulties mentioned earlier need not be insurmountable.

A second lesson from this example is that economic and market based incentives

for adequate resource and environmental stewardship go hand in hand with technical

solutions that make it possible to capture the economic benefits. While SRI as strictly

defined does not represent a distinct technology, it does represent an important set of

management principles rooted in agronomy and related sciences. In order to realize the

changes in water management that will have a discernible impact on a regional or perhaps

global scale, the principles embodied in SRI should be build into specific technologies

aimed at reducing water use in irrigated agriculture while at the same time providing

incentives to apply these technologies. These incentives as we have noted may take the

form of reduced costs of irrigation or income generation through the sale of saved water.

Especially in the poor regions of the world where normative considerations make the

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provision of irrigation water at full cost practically and politically untenable, technologies

that will reduce water use but also provide the means for capturing the benefits of such

saving provide a realistic strategy in solving excessive water use issues in agriculture.

Box 2: Policy Innovations for Successful Smallholder Irrigation Water Management

According to the international water management institute, policy thinking needs to shift from reform of

smallholder irrigation management, to the development of interventions that significantly enhance

smallholder productivity and incomes. The institutions appropriate for this are probably not pure Water

User Associations, but either farmer controlled organizations with a much broader mandate and

capacity, or specialized marketing associations with strong institutional links with agri-businesses. In a

comparative analysis of state disengagement from smallholder pump irrigation schemes in two areas of

the Senegal Valley, farmers who were involved in farmer organizations created to cushion the effects of

abrupt withdrawal fared better than those who were not. The project, however, faced great difficulties in

organizing farmers to take up activities formerly performed by the state and found it particularly

difficult to successfully organize small farmers in separate bodies, i.e., one to provide credit, another to

supply inputs, and yet another to maintain pumps. Policymakers must devise new, more farm-centered

models as they reform irrigation management agencies to operate in the wake of estate-mode farming.

Another consideration that should be built into reform is institutional ability to recognize and respond to

local conditions. The relatively high performance of farmer management in South Asian hill irrigation

schemes, for example, may be attributed to the tradition of collective self management of irrigation that

prevailed there for several hundred years. Turkey provides another example of successful irrigation

management transfer (IMT) built on a longstanding tradition of farmer participation in the maintenance

of the irrigation system through informal village-level organizations. Enabling institutions to build IMT

on existing informal mechanisms of local cooperation is likely to result in more successful farmer

managed irrigation schemes. (Source: The material is quoted from International Water Management

Institute Policy brief No. 6 January 2003. websitehttp://.iwmi.cgiar.org)

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Conventional Rice Cultivation

Rice has fed more people over a longer time than any other crop to date (Huke

1990). Today rice is grown across the globe with almost 80, mostly developing, nations

combining to produce more than 570 million tones in 2002 (Narciso 2003). Because of

this vast global distribution many variations to rice cultivation exists. Rice is grown in

fairly dry upland areas low-lying marsh land as well as on the edges of rivers and lakes.

The individual systems practiced by farmers are as different as the nations in

which they live. There are however five principle differences between agricultural rice

systems: (1) irrigation; is water available throughout the growing season, (2) control of

water supply; can the farmers effect water patterns, (3) land; what are the site conditions,

(4) labor; how much and when it is available, and (5) markets; degree of

commercialization and infrastructure in the region. (Stoop 2002)

Despite the vast variation in methods, the accepted philosophy of rice production

in developing countries is for the most part the same. The basic idea is plant old rootlets,

apply fertilizers (if affordable), and maintain flooded conditions. Seedlings are

traditionally transplanted from nurseries in clumps of 5 or more when they are more than

25 days old (Koma 2004). The clumps are then pushed into a flooded field that in close

spacing. Some fields are arranged into grids but many are not. This process is typically

not done delicately and seedlings are often damaged during this process which can be an

upward of three day journey for the seedlings (Koma 2004). The field is then flooded.

Many of the differences in regional methods have to do with the manipulation of water.

In the lowlands they take advantage of existing water sources and in dryer upland areas

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they must stock pile water during the wet season in order to maintain to constant water on

the fields. The water is not only used to supply nutrients but also acts as a pest and weed

management system. Some systems call for the occasional drainage of the field for short

increments, this usually occurs naturally thru drainage, and is usually coincided with

management schedules. (Huke 1990) Most of the time the plants are fully submerged or

at least the field is saturated. Henri de Laulanié found that the Malagasy farmers, and

probably most farmers around the world, believed water to be the most important nutrient

in the cultivation of rice (Laulanié 1992).

See Figures.1(a&b)

Figure 1. (Above) Rice farmers in China planting seedling clumps. (Below) Flooded field of semi-mature rice plants (Rahn 2004)

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Soil Chemistry

An important aspect to the implementation of SRI is the high requirement for

input material due does the rapid nutrient depletion associated with increased yields.

These inputs can be in the form of either chemical or organic fertilizers. This section of

the paper hopes to address these issues through a look at what causes them, as well as a

potential solution through crop rotation (cycling between rice and another crop to

increase soil nutrient level).

The importance of fertilizer to rice production cannot be understated. Maximum

yield can be achieved through appropriate quality and quantity of fertilizer application

(Mohammad 1999). However, fertilizer application is not always consistent. Anywhere

between 22-55 percent of nitrogen in the soil is mineralized after a successful rice crop

when fertilizer is applied (Mohammad 1999). While this is an acceptable number on the

surface, one must account for the costs of fertilizer application. Environmentally,

fertilizer application can lead to runoff that pollutes viable and valuable water resources.

Economically, fertilizer is expensive although labor costs in spreading fertilizer are

minimal compared to the increased labor required in the SRI system. Alternative ways of

introducing nitrogen into the soil are listed below.

Nitrogen accounts for 80 percent of the soil chemical content in rice growing

fields (Kundu 1999). Currently, nitrogen fertilizers are used to supplement the nitrogen

level in the soil. Nitrogen fertilizers lead to an improved nitrogen mineralization rate, as

well as increased uptake of nitrogen (Kunda 1999). Older rice research suggested that

constant flooding was optimal for rice production, but it is now apparent that constant

submersion has negative side effects, such as reduced soil permeability and nutrient

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runoff (Kunda 1999). SRI management techniques may remove this problem. According

to Kundu and Ladha, “subjecting soil to a drying period in intensively-cultivated wetland

rice fields, may be a mechanism by which each soil N pool is replenished from

successively more recalcitrant or physically-protected N pools. Seasonal drying of fields

can also maintain optimum physical, chemical and microbiological properties of the

soil.” In other words, drying a field (as done in SRI) may have beneficial aspects on the

long-term nutrients of soil.

Research has also shown that crop rotation systems are effective in replenishing

the nutrient level of the soil while maintaining (or encouraging) a high yield. After a one-

year drop in yield, a field incorporating tomato and pepper crops rotating with rice

production saw a large increase in yield, as well as available nutrients (Pascua et al.,

1999). When these systems were supplemented with nitrogen fertilizer, the yield

increased further. Timing is a very crucial aspect of this technique. If the fertilizer is not

applied or the crops are not planted at the correct time, the yield will not see significant

improvement (Pascua 1999). Witt et al. (1998) agree with this assessment, finding that

“these factors [crop rotation] have agronomically significant effects on rice nitrogen

uptake and yield.” They argue that soil aeration (exposure to air) is necessary to see the

positive effects of crop rotation (Witt 1998).

Nutrient and crop management in hydrated fields was found to increase rice

production profitability by anywhere from $4-82 over one year (Dobermann 2002). If this

success can be translated into aerated rice production, it could be a very effective tool in

promoting SRI. Site-specific nutrient management (SSNM) is the name of the system of

nutrient and crop management. Many local fields have drastically different nitrogen

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contents than what is assumed by fertilizer producers, and SSNM can be very successful

in those areas (Dobermann 2002). The argument is that fertilizers are expensive and

ineffective, while SSNM presents an opportunity to increase yield through “small,

incremental steps that involve gradual buildup of soil fertility and fine-tuning of crop

management” (Dobermann 2002).

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Labor Intensification

Systems of Rice Intensification have been successfully adopted in nearly every

corner of the globe. Systems of Rice Intensification maximize the rice plant’s natural

productivity potential. As the productivity of land, labor and water are raised

concurrently; rice yields and farmer profits increase. The benefits of SRI have been

researched and documented in thousands of case studies in hundreds of developing

nations. “Though costs of production are higher because of labor, the higher yields more

than compensate and relative profitability of SRI is better (BRAC, 2001).”

The labor intensification of SRI can be divided into 3 categories; land preparation,

transplanting and weeding. While SRI methods do increase the time and labor needed to

successfully complete each of these tasks, each and every case study in CIIFAD’s report

show that despite increased labor costs, farmers still profit from SRI. One study found

that SRI requires 2/3 days more labor per hectare in the first and second year (CIIFAD

2002). Fortunately, this value improves because there is a learning curve. After farmers

grow accustomed to the techniques and become more efficient with its practices, SRI was

calculated to only require 25% more labor that conventional rice growing methods.

Transplanting is the portion of the SRI method that requires the most labor

intensification. Even so, transplanting takes less time that standard practices because

fewer seeds are dealt with. Recommended plant spacing is larger with SRI and therefore

the time needed to transplant is offset by fewer plants actually needing to be handled

(SRI seed rate is 5-10 kg per hectare while conventionally 50-100 kg seed per hectare

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were used). (CIIFAD 2002) The extra time spent planting the smaller, individual

seedlings is saved by low planting density.

In each and every developing country that SRI has been adopted, the studies

demonstrate the same results. Initially yes, SRI methodology requires a higher input of

labor because of its management intensive practices. People are needed to carefully

transplant smaller seedlings and perform extensive weeding. However, the profit margin

of individual farmers in greatly increased because of higher rice yields and costs are

saved in other areas of the rice growing processes.

In Sri Lanka hundreds of farmers adapted to the SRI cultivation method. Across

the board, farmers in dry areas, intermediate and high rainfall zones all experienced the

same lucrative results. The average farmer at least doubled their rice yield. One farmer

measured the noticeable savings on labor from not having to apply agrochemicals four

times per season. “With the conventional system his production was 2,205 kg of paddy,

valued at Rs.28665 whereas his production with SRI was 3750kg valued at Rs.49140.

The increased cost of labor for the SRI operation was 14% but total return from SRI was

71% higher.” The value of labor intensification becomes recognized when and only

when all opportunity costs are factored into farmer’s agricultural equations.

(Rabenandrasana 2002)

In Bangladesh farmers represent 2/3 of the workforce. In this agriculturally based

economy, rice covers 75% of the crop area. The Bangladesh Agricultural Research

Council has expressed a need for an improvement on High Yield Varieties because such

strains of rice depend on expensive chemical and technical inputs (Gamini 2002). SRI is

therefore an attractive prospect for the people of Bangladesh, being the 8th most

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populated nations in the world and densely so with 2,624 people per square mile.

(CIIFAD 2002). Farmers in Bangladesh are currently investigating the benefits of SRI.

Results could fair to be promising as a result of the high availability of labor.

There has been a government initiative in Cuba to reduce rice imports as part of

an overarching plan to increase agricultural self sufficiency and food sovereignty. There

has thus been a shift towards new and improved methods of cultivation, SRI being one of

them. There are not only economic and environmental but societal ramifications of SRI.

Under rice intensification, the comparative advantage of labor induces farmers to favor

women and children workers because they can more efficiently transplant the

recommended small seedlings with their small, nimble fingers (Perez 2002). In addition,

women and children are just as effectively able to do the increased amount of weeding

necessary for rice intensification.

Rice is the stable food crop in Gambia, as in many West African countries. Case

studies conducted on actual farms demonstrated yields that consistently tripled those of

conventional methods (Ceesay 2002). Farmers paid for this increased productivity with

more labor. In Indonesia, the average farmer that adapted to SRI practices experienced

yields that were 16.4% higher while some farmer were able to increase their productivity

by as much as 51%. (Las 2002) Indonesia is an example of how cultural attitudes

determine the actions of market participants. The incredibly high yields that were

achieved in Indonesia were almost never recognized because many farmers and laborers

were initially, strongly opposed to the SRI method. Centuries of experience passed down

through the generations caused Indonesians farmers to fear that smaller seedlings would

be more readily consumed by the destructive golden snail. However, the intermittent

27

flooding of SRI effectively reduced the golden snail population. Good news traveled fast

and thousands of farmers across the nation have since adapted to the principles of SRI.

Indonesia demonstrates that cultural considerations determine the success or failure of

agricultural reform. Extensionists, scientists, researchers and policy makers must make a

concerted effort to be culturally sensitive and socially conscious of their actions because

the needs of farmers and laborers need to be addressed first and foremost in order for

positive change to come about.

Weeds grow more prolifically on SRI soils because they are not flooded. The

factor of labor is thus increased in order to control their growth. The opportunity cost of

paying extra laborers to weed must be measured against the money saved from decreased

pesticide, herbicide, weedicide and fungicide purchases. Farmer profitability is increased

under SRI because of decreased chemical input costs in conjunction with higher rice

yields. Farmers can potentially increase profits even more by increasing the productivity

of each laborer. In the Philippines, farmers provide their workers with hand pushed

weeders that remove the pests as well as oxygenate the soil (Gasparillo 2002). Simple

mechanical weeders or rotating hoes greatly increase crop yields and the vitality of rice

plants while simultaneously increasing farmer profits by decreasing the cost of labor and

herbicides. Furthermore, the average farmer in the Philippines multiplied their rice yield

by a factor of 2 with SRI practices.

In a thesis research project conducted in Morondava Madagascar, Frederic

Bonlieu demonstrated in his case study that SRI gives high returns to labor. Even though

SRI methods increase the cost of labor by approximately 5000,000 FMG, (the Malagasy

franc) 95% of the farmers that utilized the SRI yielded higher rice harvests. SRI averages

28

were 77% than conventional agricultural rice yields (Bruno 2002). In more that 90% of

the experimental groups, farmers that utilized SRI measured at least 2 tons/ha more than

the control group farmers. This 2 ton/ha increase is a significant because the price of rice

in Madagascar ranges from 3500 to 4200 FMG/kg. Research showed that even though

labor is an expensive investment for farmers to make, the returns on such an investment

are extremely profitably (Andriamanarivo and Rajaonnilison 2002). In addition, the

above calculations do not take into account the indirect monies farmers will save from

SRI practices. Bonlieu estimated savings on seeds to average at about 40kg/ha. The

benefits of reduced water costs, diminished need for agrochemical inputs, savings on seed

and increased rice yields will out weigh the increased cost of labor for the successful

implementation of SRI in developing countries.

Three hundred farmers in Sri Lanka were involved in a comparative case study.

These farmers were broken down into three groups; those who continued with their usual

practice yielded 2.9 tons/ha, those who followed the government recommended strategy

of growing rice yielded 4.7 tons/ha and those farmers that used SRI yielded 8.5 tons/ha.

The results of this study clearly show that SRI is the most productive method of rice

farming. Furthermore, costs of production were calculated to be 6, 5.65 and 3 rupees,

respectively for each of the groups. Even though the amount of money invested in labor

was greatly increases, SRI still proved to be the most attractive option for Sri Lankan

farmers (CIIFAD 2002). As a side note, Environmental strains are significant in Sri

Lanka as the country struggles to compete in the global market, to overcome a history

filled with ethnic conflict and provide an adequate standard of living for its mushrooming

population. Health hazards and the destruction of biodiversity induced by agrochemicals

29

are a major concern to the people of this small island nation. The Buddhists clergy in Sri

Lanka has actually taken a position on this issue and openly endorses SRI practices

because they do not require chemical biocides or the subsidized fertilizer that the

government promotes with its rice growing initiatives. The profit potential from SRI

methods will economically and environmentally benefit the farmers, laborers and

consumers of Sri Lanka.

30

Labor Intensification and the Feasibility of SRI

Although SRI has consistently proven to conserve water, generate profit, multiply

rice yields, decrease chemical use, help the environment and improve soil health, some

farmers are still unable to achieve these benefits. The feasibility and sustainability of SRI

are difficult to assess because costs, income and capital vary for each and every farmer.

Labor costs are a limiting factor, making SRI unsustainable for certain farmers.

Despite the obvious benefits of SRI the implementation of SRI is infeasible for

many farmers in developing countries because of the increased cost of labor

intensification. Christine Moser of the Applied Economic Department of Cornell

University did a case study of twenty five farmers in Madagascar to explain why 40% of

those who adopted SRI later abandoned its practices (CIIFAD 2002). While SRI requires

few external inputs and does yield higher crops rates and increased profits, most farmers

cannot afford the high labor investment necessary to reap the rewards. It would seem that

poverty stricken farmers would have the most to gain from SRI and its decreased need for

expensive agrochemical products. However, the cash constraints on poor farmers prevent

SRI agricultural reforms from being sustained because of high labor costs. Studies

consistently show that SRI requires approximately 25% more labor than conventional

rice growing practices (CIIFAD 2002). Between growing seasons, poor farmers are

forced to work for wages on wealthier farms, thus leaving time to complete the extra

labor required for SRI. Furthermore, these farmers have no extra funds to hire other

laborers. “The opportunity costs of investing in SRI are very high” for families that live

hand to mouth. Moser concluded from her case study that farmers with higher incomes

and rice surpluses were more economically able to afford the investment in labor.

31

Wealthier farmers have the economic means to sustain SRI practices and thus are

fortunate enough to benefit from increased rice yields and its resulting profits.

32

Conclusive Recommendations and Solutions

The practices and principles associated with Systems of Rice Intensification have

proven case study after case study to benefit farmers, consumers, the environment, local

and macro economies. The economic incentives of SRI have created monetary and

ecological profits for thousands of people in dozens of developing countries around the

world. Water conservation, high seed to crop ratio and the reduction of external inputs

are the key characteristics of SRI that save farmers money. Crop yields increase by tons

per per acre. Increased sales translate to higher profits. Farmers benefit from adapting to

SRI methodology economically and ecologically.

The benefits of SRI are universal. Environmental vitality is ensured with the

decreased use of agrochemical products. Precious water resources are conserved with

reduced water use. Soil vitality actually improves with organic farming and green

manure. The practices and principles of SRI maximize the rice plants’ natural earning

potential. SRI raises the gains on each agricultural input. SRI raises the factor

productivity of land, labor and capital. In turn, farmers economically profit from the

higher yields of SRI. Despite the obvious earning potential of SRI, the increased cost of

labor prevents poor farmers from utilizing intensification methodology. Unfortunately

there is no clear solution to the limitations imposed by poverty. There are however

multifaceted socioeconomic initiatives that could potentially alleviate some of the cash

constraints on poor farmers thus giving them to opportunity to adapt to the beneficial

practices of SRI.

With labor imposing the most formidable obstacle for poor farmers to overcome,

microeconomic management could alleviate cash constraints on poverty stricken farmers

33

thus enabling them to sustain the beneficial practices of SRI. Governments, NGOs or

various financial institutions could assist the simple transition to SRI by providing

farmers with access to credit at reasonable interest rates (CIIFAD 2002). Capital

flexibility enables farmers to invest in the future and thus make economic decisions about

potential earning rather than exclusively considering present valuation. Farmers that

have the capital means to buy agricultural equipment can increase the productivity of

their labor input and thus decrease their labor costs. When subsistence farmers live hand

to mouth growing enough food for dinner is more important than purchasing a weeder or

ox. However, if farmers had access to credit at reasonable interest rates they could

potentially increase their factors of productivity, crop yields and most importantly profits.

The diversification of income can ensure economic stability between growing seasons

(CIIFAD 2002). Income diversification could simply mean crop diversification. If

farmers adopted polycultural practices or planted cash crops in addition to rice, they

could maximize the productivity of their land while increasing earnings and food

stability, especially during the hungry season that farmers in developing nations struggle

through annually. Additionally, crop rotation systems can improve soil chemistry while

generating alternative means of income.

Governments, NGOs and extensionists have the ability to facilitate the adaptation

of agricultural methodology to SRI through existing institutions. Every nation in the

world has their variation on The Ministry of Agriculture. The infrastructure already

present through such bureaucracies could be utilized for the purposes of SRI. Farmers

need to be educated on the principles and practices of this sustainable agricultural

method. Higher crop yields and increased productivity can only be recognized by those

34

farmers that can afford the initial costs of labor intensification. Agricultural guilds and

farming cooperatives could be created or those that already have members could join

together and assist one another by sharing labor. Most farmers do not have the means to

harvest their own fields let alone pay other laborers to do the extra work required by SRI.

However, if seeding, transplanting, flooding and harvesting were coordinated through

agricultural association, careful coordination and staggered timing could enable farmers

to share the labor and thus increase output together, by a larger factor. Private ownership

of land could remain intact, only the increased yields and profit would be shared.

Countless other reforms could potentially facilitate farmers in developing nations to adapt

to the principles and practices of SRI.

The universal benefits of an SRI revolution will not only improve the lives of

thousands of individual farmers by increasing input factor productivity, crop yields and

profits but also protecting the environment from degradation caused by agriculture. The

benefits of SRI are multiplicative. If thousands of farmers utilize SRI, millions of gallons

of agrochemicals will not be applied to crops and billions of gallons of water will be

conserved. Furthermore, perhaps less natural environments will be converted to

agricultural land because of SRI productivity. Although many obstacles have prevented

the widespread use of SRI thus far, this cultivation transformation cannot happen by itself

and thus can only improve the lives of rice farmers if a concerted effort is made by NGOs

or governments in developing nations to facilitate this economically and environmentally

beneficial process.

35

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