Maclean et al. - 2002 - Rice almanac source book for the most important e

Recent developments in the rice sector
The gross domestic product was estimated at
US$27.2 billion for 1998. Agriculture continues
to play a dominant role, contributing 21% to the
GDP and 30% of total export earnings.
Rice is the single most important crop. It is
cultivated on 4.2 million ha out of 5.7 million ha
of arable land. The planted area for rice increased
from 5.6 million ha in 1980 to 7.7 million ha in
2000. Cropping intensity has reached 183%, the
highest in the world. The rapid increase in rice
area and the intensity of rice cropping have been
made possible by heavy investment in flood
control, drainage, irrigation that turned the floodprone
ecosystem in the Mekong River Delta into
an irrigated ecosystem, and the development of
very short duration rice varieties.
In 1981, Vietnam departed from the
collective agricultural production system by
introducing the group-oriented contract system of
production. That was changed to individual
contracts, beginning in 1986. The average farm
size is very small. The number of farm
households was estimated at 9.5 million in 1994,
with 8.4 million having a size of less than 1 ha.
By official estimates, the average small-farm
household’s share of income from the crops it
harvests has risen from 20% before the 1986
reforms to around 60% in the mid-1990s.
Vietnam achieved an impressive growth in
rice production after the policy reforms in 1986.
Total output increased from 15.1 million t in 1987
to 32.6 million t in 2000, a growth of 6.1%/year.
Much of the growth came from the expansion of
the rice harvested area, as farmers shifted land
from a long-duration single-cropped deepwater
rice to double- and triple-cropped short-duration,
high-yielding modern varieties, particularly in the
south. There has also been an impressive growth
in rice yield, from 2.70 t/ha in 1987 to 4.25 t/ha in
2000, a growth of 3.3%/year.
As a result of the spectacular growth in rice
production, Vietnam has been a major rice
exporter since 1989. Initially, it captured the
international market for low-quality rice, but over
time the milling quality has improved. Exports of
milled rice have continuously increased from 1.4
million t in 1989 to 4.6 million t in 1999. Vietnam
is now the second largest exporter of rice in the
world market, after Thailand.
Rice environments
About 52% of Vietnam’s rice is produced in the
Mekong River Delta and another 18% in the Red
River Delta. The other major rice-growing
regions are the northeast and the north-central
coast. The northern provinces of Vietnam have a
total rice area of 2.5 million ha or about a third of
the total rice planted area. Almost 85% of the
total area is irrigated lowland, 12% is shallow
rainfed, and 4% is intermediate rainfed. The
dominant cropping pattern is spring-summer rice.
The Red River Delta, which is extremely
densely settled and has very small landholdings,
has long been practicing double rice cropping
with highly labor-intensive rice cultivation
methods. The winter and spring season rice crops
cover almost the same area (530,000 ha), with a
yield of 5.2 and 5.7 t/ha, respectively.
The Mekong River Delta has three major
cropping seasons: spring or early season, autumn
or midseason, and winter, the long-duration wetseason
crop. The largest rice area is cropped
during the autumn season (1.95 million ha),
followed by spring (1.45 million ha), and only a
small area is cropped in winter (0.6 million ha).
The rice yield is highest in the spring season (5.3
t/ha), and lowest in the winter season (3.3 t/ha).
Farmers in this region adopt a direct-seeding
method of crop establishment to save labor costs.
Fifty-two percent of the rice in the Mekong River
Delta is grown in irrigated lowlands, with the
remaining 48% grown under rainfed conditions.
Soils in the Mekong River Delta are highly
variable, but alluvial, acid-sulfate, and saline
soils predominate. Acid-sulfate soils cover some
1.6 million ha, or 40% of the delta, mainly in the
Plain of Reeds, Long Xuyen Quadrangle, and Ca
Mau Peninsula. The soil is rich in humus and
total N, but low in P. In addition, Al and Fe
toxicities limit yield.
Alluvial soils, prevalent in 30% of the
Mekong River Delta, are concentrated along the
banks of the Tien (Mekong) and Hau (Bassac)
rivers. This is the best soil in the delta, with
humus content of 2%, total N of 0.1–0.25%, and
medium P and K. Two to three crops can be
grown on these soils each year.
Coastal saline soils occupy about 20% of the
total area. The soils are rich in humus, N, and
clay (55–60%), but have a high salt content.
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