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The High Barind Tract: a challengingdrought-prone agriculturalenvironmentC.R. RichesThe Barind Tract is a distinctive physiographic unit comprising a series of upliftedblocks of terraced land covering 8,720 km 2 in northwestern Bangladesh betweenthe floodplains of the Padma (known as the Ganges in India) and the Jamunarivers (the main channel of the lower Brahmaputra). Spread over parts of thegreater districts of Rajshahi, Dinajpur, Rangpur, and Bogra of Bangladesh, andMaldah District of West Bengal in India, the Barind includes 773,000 ha inBangladesh, of which 532,000 ha are cultivable. Rainfall is comparatively lowin this region, with the long-term average being about 1,250 mm in the westand 2,000 mm in the northeast, occurring mainly from late April to October.With a variable rainfall and temperature ranging from 25 to 35 °C (regularlyexceeding 40 °C) in the monsoon season, the area is considered semiarid anddrought-prone. The aman rice 1 (monsoon)-growing season ranges from 180days in the west to 220 days in the northeast but the frequency of dry periods,particularly in July and August, is the highest in the country. The Barind is at acomparatively higher elevation than the adjoining floodplain and there are twoterrace levels—one at 40 m above sea level and the other between 19.8 and22.9 m. Therefore, when the floodplains go under water during the monsoon,the Barind Tract remains relatively free from flooding and is drained by a fewsmall streams. About 47% of the Barind region is classified as highland, about41% as medium highland, and the rest is lowlands. Although 55% of the Barindwas forest in 1850, subsequent rapid population growth resulted in 70% of theland being converted to arable land by 1970. The area is now characterized byterraced slopes with bunded fields without water control other than drainageby gravity to lower-lying fields and streams.The High Barind Tract, lying in Rajshahi, Chapai Nawabganj, and Naogaon districts,is one of three distinct areas of the Barind, occupying 160,000 ha, roughly 21% ofthe region. This is the most marginal area of the Barind Tract for rainfed cropping,accounting for 12% of the drought-prone lowland rice land in Bangladesh. As shown1 Rice in the aman growing season is usually transplanted. Traditionally, farmers used photoperiod-sensitivevarieties to fix optimum flowering and harvesting dates. Modern varieties are insensitive to photoperiodand seedlings for long-duration varieties such as Swarna (> 150 days) must be planted from mid-July tomid-August for optimum yield (Zaman 1986).
Table 1. Variability in the start and end dates for combined monsoon (aus and aman) andrabi growing seasons at Rajshahi, High Barind Tract, 1947-84.Timing Earliest date 25% probability Mean date 75% probability Latest dateBegin 18 April 12 May 25 May 8 June 23 JulyEnd 6 October 3 December 28 December 9 January 20 FebruarySource: Brammer (2000).by Table 1, variability in total rainfall, timing of onset, and cessation of the rain aswell as occurrence of in-season drought periods mean that farmers must use a flexible,opportunistic approach to cropping decisions and experience considerable annual variationin production. Rice in the aus season, 2 either broadcast-seeded or transplanted onearly premonsoon showers, is important for food security in the monga period (hungryseason) of September-October prior to harvest of the main aman crop. However, theaus crop may experience drought in April to early June while in wet years seedlingscan be damaged by premature flooding.Land in the High Barind Tract exhibits gray terrace soil, is silt loam to silty clayin texture, and is poorly drained, with a 6–8-cm thick plow pan and low organicmatter content (0.8–1.2%). Most land lies fallow during the aus season and underthe traditional farming system farmers grow a single crop of transplanted rice in theaman season established after the first week of June when the onset of the monsoon isexpected in three years out of four. A premature end of the monsoon in early Octoberbrings terminal drought at grain filling, particularly for late-transplanted aman crops.Indeed, the probability of 10- and 15-day dry spells during grain filling is 73% and53%, respectively, so that a 2-week period without rain during the grain-filling periodof currently grown rice cultivars is expected once in two years. Soil moisture remainingat aman harvest in late October to late November varies from year to year and isgenerally sufficient only for an early, quick-maturing crop to be grown satisfactorilyin the postrice rabi season. There is sufficient moisture for a wheat crop to be grownwithout irrigation in the rabi season only once in four years when showers extend tomid-February. As a result of the low probability of significant rainfall after mid-October,some 80% of the area currently lies fallow in the rabi season. Approximately20,000 ha are sown to a range of drought-tolerant rabi crops planted on residual soilmoisture after the rice harvest, including chickpea, linseed, and mustard, or wheatwhere irrigation from farm ponds is available.The use of groundwater for irrigation of boro rice in the rabi season has beena major policy option contributing to a near threefold increase in rice production inBangladesh since 1960. Since 1985, the Barind Multipurpose Development Projecthas installed a network of more than 5,000 deep tube wells, bringing 162,000 ha under2Rice in the aus growing season is photoperiod-insensitive, short-duration (90–110 days), and usuallysensitive to cold (temperature below 20 °C will cause stunted growth and sterility). It is generally grownrainfed as a broadcast or transplanted crop and planted optimally between mid-March and mid-April (Zaman1986).Riches
Page 2: Improving AgriculturalProductivity
Page 5: Bangladeshi experiences with a drum
Page 8: AcknowledgmentsIRRI is most gratefu
Page 14 and 15: irrigation across the entire Barind
Page 16: Workshop synthesis
Page 19 and 20: and, with representatives from the
Page 21 and 22: Subsistence pressureLand pressure,
Page 23 and 24: HerbicidesEarlier efforts to introd
Page 25 and 26: volume). PVS is an effective way to
Page 27 and 28: Farmers may use wet-seeded DSR as a
Page 29 and 30: process and distributing HNPV to fa
Page 31 and 32: an NGO, have successfully collabora
Page 34 and 35: Workshop discussionParticipants dis
Page 36 and 37: How can we identify a short-duratio
Page 38 and 39: to fixed tenancy. The implication i
Page 40: Opportunities for improving ricepro
Page 43 and 44: that the reliability and productivi
Page 45 and 46: Table 1. Planting dates, direct-see
Page 47 and 48: Table 2. (A) Mean effect of fertili
Page 49 and 50: Table 5. On-farm trials of a drum s
Page 51 and 52: Upper toposequenceYield (t ha -1 )7
Page 53 and 54: and perennial grasses (e.g., Ischae
Page 56 and 57: Direct-seeded rice in the HighBarin
Page 58: Table 1. Sample selection for costs
Page 61 and 62:
Table 4. Variations in weed managem
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Table 7. Labor requirements (days h
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Table 10. Farmer perceptions of dis
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Farmers (no.)1412108DSRWet-seededDr
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able commercially. Other OFT farmer
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Box 1. Farmers’ comments on DSRPo
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NotesAuthors’ addresses: M.A. Jab
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This paper explores the role of som
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(Olsen method, atomic absorption),
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Mean biomass (g m −2 )1,000.000Fi
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Fig. 3. Log rank abundance of weed
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attested by Fig. 2). Diversity in t
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Bangladeshi experiences with a drum
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Table 1. Grain yield and crop durat
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Table 5. Grain yield and growth dur
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ACEy = 0.0001x + 0.7089Yield (t ha
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Table 11. Partial budget analysis f
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ConclusionsDirect wet-seeded rice u
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A 178% increase in rice production
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Table 1. Components of yield gaps d
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Table 3. Weed management in Comilla
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Table 5. Weed management practices
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Table 7. Significance (P H o ) of t
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Since 2000, there has been an incre
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Identifying varieties for the High
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Table 1. Rice varieties bred by cli
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Table 2. Grain yield advantage of J
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Table 3. Plant height and crop dura
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Table 6. Summary of adoption and sp
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Freeman GH, Perkins J.M. 1971. Envi
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Opportunities for improving rabi cr
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Grain yield (t ha -1 )2.0npp1.5LSD
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In each of the plots, numbers of He
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Table 2. Effect of IPM components o
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Unit plot size was 10 10 m and the
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Yield (t ha -1 )5Straw4321GrainP (g
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Nodulation score3AControl Soil Mo P
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even at low levels of production. B
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Integration of chickpea and other r
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Grain yield (t ha -1 )3.02.51989-99
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Improved Improved Rainfed rainfed C
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Table 1. Preharvest and postharvest
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Greater resistance to Helicoverpa p
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wheat varieties). There is also sco
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Developing seed systems fordissemin
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This paper describes attempts to em
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seed needed to attain the recommend
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introduced to permit sale beyond th
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pesticides, inoculation with benefi
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for the rabi crop in 2001. Hence, b
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where farmers decided not to relay-
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Table 2. Mean dates of T. aman harv
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Table 4. Subsistence pressure and r
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Table 7. Subsistence pressure and r
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cite the absence of rent as a facto
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abi cropping in the HBT through ear
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Formulation and dissemination ofimp
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in India, for which shorter-duratio
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Applied researchOFTsAdaptive resear
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Table 1. Recommended package of pra
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Table 2. Grain yields (kg ha -1 ) o
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Table 4. Grain yields (t ha -1 ) of
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Table 6. Mean grain yields (t ha -1
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constraints present. This in itself
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Extending rabi cropping in rice fal
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Table 1. Estimates of rice area dur
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Yield (kg ha -1 )1,2001,00080060040
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Future disseminationThrough dialogu
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Direct seeding of rice andopportuni
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Table 1. Time of establishment and
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Table 3. Weed density and biomass a
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than in Central Java and many farme
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Proportion abundance (log scale)Ran
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CAN FIELD BE DRAINED?YesCAN FIELD B
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Johnson DE, Mortimer AM. 2005. Issu
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Zhao DL, Atlin GN, Bastiaans L, Spi
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