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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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21
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
22
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
23
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
25
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
26
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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