Rice-Wheat Atlas of Bangladesh

Transcription

1 Rice-Wheat Atlas of Bangladesh Eleanor Huke, Robert Huke, and Terence Woodhead IRRI IN'raRNATIONAL RICE REsEARQ{ INSTITUTE '' GMMYT International Maize and Wheat Improvement Center ~WW-ti ~~) ~8ARC~ BARC Bangladesh Agricultural Research Council

2 Rice-Wheat Atlas of Bangladesh Eleanor Hulce, Robert Hulce, and Terence Woodhead IRRI IN'lnNATIONALRl:CE REsEAROi INsmurE International '' C MYT Maize and Wheat Improvement Center.) BARC ~llarc~ Bangladesh Agricultural Research Council

3 International Rice Research Institute P.O. Box Manila Philippines Centro Internacional de Mejoramiento de Maiz y Trigo International Maize and Wheat Improvement Center Lisboa 27 Apdo. Postal Mexico D.F. Mexico Bangladesh Agricultural Research Council Airport Road Farm Gate Dhaka Bangladesh

4 PREFACE The maps and text in this atlas seek to illustrate and interpret various spatial changes that have occurred in the Bangladesh rice and wheat production systems during the past three decades. This atlas is one of a series of five : similar mappings and texts have been compiled for four other major rice-wheatgrowing countries (China, India, Nepal, and Pakistan) as part of a collaboration among national agricultural research systems, the International Maize and Wheat Improvement Center (CIMMYT), and the International Rice Research Institute (IRRI). For each of the five countries, the objective of the compilation was to aggregate, display and interpret agricultural statistics that relate to the production, productivity, and sustainability of rice-wheat cropping sequences, in which monsoon-season rice (usually grown on irrigated puddled soil) is followed in the same field by wheat (also irrigated) that grows during cooler, drier months. However, compilations of agricultural statistics usually relate to individual crops (such as rice or wheat), rath~r than particular crop sequences (such as rice-wheat or jute-rice-wheat). Analytical procedures to estimate statistics for the rice-wheat sequences were therefore developed, and are described in the atlas' explanatory texts. The maps and their database were assembled and processed using the Atlas*Pro mapping system and a Macintosh-Plus computer. For Bangladesh, and other South Asian countries, the data and maps were processed and presented by greater district or by district; for China, analyses were made at the next-higher level of governance - the administrative provinces. For all countries, copies of the database are available from IRRI's Geographic Information Systems Laboratory, and request may also be made to that Laboratory for a mapping of any component of the database that is needed in a format that is different from that used in these atlases. For Bangladesh, our analyses indicate that rice-wheat-sequence cropping has increased in total area by some eight-fold during 1960 to 1990, with substantial increases in the greater districts of Comilla, Faridpur, and Rajshahi. Rice-wheat cropping now occupies 5% - an appreciable proportion - of the Bangladesh total of arable plus permanently cropped land. However, the analyses indicate also that proportional increases in production of rice-plus-wheat (whether grown in sequence or otherwise) were less than the proportional increases in human population during 1960 to such that per caput iii

5 production of rice-plus-wheat decreased from 234 to 209 kg grain/year. But there are indications that since 1980 annual increases in production may in fact be equal to annual increases in population. Collectively, our five individual-country atlases indicate that areas of rice-wheat cropping now involve about 0.5 Mha in Bangladesh, 9.1 Mha in China, 9.2 Mha in India, 0.4 Mha in Nepal, and 1.4 Mha in Pakistan. The total area, about 21 Mha, represents about one-third of Asia's total of irrigated riceland, and a rather larger fraction of its irrigated wheatland. The rice-wheat sequences of South Asia and China thus constitute a major component of Asia's food-production system. It is the hope of the authors that this set of five atlases will help enhance knowledge and awareness of these important sequences. For this Bangladesh atlas, the maps and interpretations have drawn extensively on the experience and wisdom of several colleagues in Bangladesh, at CIMMYT, and at IRRI. We acknowledge the helpful discussions with all of those colleagues, and also the invaluable contributions made by many anonymous enumerators and compilers of agricultural and human-population statistics. For assistance in preparing the database, maps, and text, and in producing the compiled atlas, we sincerely thank Edna-Marie de San Agustin Punzalan, Remedios Lagac, Laarni Balababa, Jesus Recuenco, and Rosario Jimenez. Publication of this atlas was made possible in part through a Technical Assistance Grant provided by the Asian Development Bank. December 1993 Eleanor Huke, Robert Huke, and Terence Woodhead l.v

6 CONTENTS iii Preface 1 Objective of the atlas 1 Rice-wheat cropping sequences in Bangladesh 3 Procedures of map-making 6 The maps and their interpretation Map 1 Map 2 Map 3 Map 4 Map 5 Map 6 Map 7 Map 8 Map 9 MaplO Map 11 Map 12 Map13 Map14 Map15 Map 16 Map 17 Map 18 Map 19 Base map of Bangladesh by greater district Rice area Rice area Change in rice area to Wheat area Wheat area Change in wheat area to Rice-wheat-sequence area Rice-wheat-sequence area Change in rice-wheat-sequence area to Rice-wheat as fraction of land area Rice-wheat as fraction of land area Proportional change in rice-wheat area to Human population 1960 Human population 1990 Change in population 1960 to 1990 Rice plus wheat production per caput Rice plus wheat production per caput Change in rice plus wheat per caput to References cited v

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8 OBJECTIVE OF THE ATLAS This atlas of rice-wheat systems in Bangladesh is part of a project to construct a geographic, economic, and biophysical database for those rice-wheat systems. That database will support research and technology-extension activities that aim to raise the profitability and sustainability of productivity in the various cropping sequences that include both rice and wheat. Similar projects are underway for the rice-wheat systems of China, India, Nepal, and Pakistan. A preliminary (combined) atlas for the four South Asian countries was compiled earlierl. The database and atlases will facilitate the analysis and display of features and variables that affect the production, productivity, profitability, and sustainability of rice-wheat systems. They will also allow the analyses for each country to discriminate among specific administrative units (such as provinces, divisions, districts, or greater districts), and eventually among agroecological zones. A prerequisite of the analyses is an identification of the locations and areal extent (and time trends) within countries of the rice-wheat sequential cropping (agricultural statistics are more generally assembled according to individual crops rather than to cropping sequences). Such identification allows estimation of the total extent of rice-wheat and its magnitude in relation to alternative cropping or farming systems. Knowledge of this extent and magnitude, together with interpretations that identify factors that locally constrain or enhance rice-wheat productivity and profitability, will suggest zonal or divisional priorities for policy on infrastructural or trade interventions, for technology-extension, and for research. Ratios of rice and wheat productions to human population for a particular district or division - and the time-trends in those ratios - will quantify the extent to which farmers (including rice-wheat-sequence farmers) have been able to maintain or increase per caput production of the two staples. Trends in these ratios can be analyzed in relation to biophysical and socioeconomic components of the database. Thus, districts or greater districts that have previously been able to increase the production/ population ratio, but for which the database identifies emerging constraints to productivity, or for which in recent years there has been a slowdown in rates of yield increase, may be identified, and appropriate responses defined. RICE-WHEAT CROPPING SEQUENCES IN BANGLADESH In several parts of Bangladesh, rice and wheat are grown sequentially in the same field in the same farming year, in one or another of several distinct cropping patterns - including rice-wheat, rice-rice-wheat, jute-rice-wheat, and rice-wheat-legume. The wheat is often 1

9 intercropped with a legume or oilseed crop2. The cropping pattern that best suits a specific location (or field) is determined in part by economics and the availability of labor and irrigation (about 20% of the Bangladesh riceland is irrigated3, and perhaps rather more of the wheat land4,5) - but primarily by the local patterns of land elevation, groundwater hydrology, and depth and likelihood of land submergence in the monsoon season6,7,8. The wheat season is necessarily during the low-sun cooler period (November to March). This period, although not rainless, is substantially drier than the high-sun, warmer, monsoon or rainy season which best suits rice. In the two types of one-rice-one-wheat annual cropping, wheat follows either an (Aus) rice-fallow sequence or a fallow-(aman) rice sequence5,7. The Aus rice is either directseeded in late March or April, or transplanted in April from March-sown nurseries, and is harvested in July. The Aman rice is transplanted in July from June-sown nurseries, and is harvested in November. For rice-rice-wheat5,7, the first (Aus) rice is either directed-seeded in March or transplanted in April, with harvest in late June or early July, and the second (Aman) rice is transplanted during mid-july to early August (using seedlings from nurseries sown in June or early July) and harvested in November or December (causing some delay to wheat sowing). In jute-rice-wheat sequences 7, jute is sown in mid-april and harvested in late July or early August; Aman rice is correspondingly transplanted as soon after jute harvest as is practicable, and is harvested in November or December. For both Aus and Aman rice, in ricewheat or rice-rice-wheat sequences, harvest dates depend not only on seeding date, but also on choices of rice cultivars. Moreover, in submergence-prone fields at low elevation, farmers may grow Boro (winter) rice in preference to wheat - especially if tubewell irrigation is available. For the transplanted rice crops, the soil puddling 7 comprises 5-6 bullock-powered ploughings and 3-4 harrowings; transplanting - in random array - is accomplished manually. For the direct-seeded rice 7 and the post-rice wheat5, seedbed preparation comprises 1 or 2 tractor-powered tine cultivations followed by 3-6 bullock-powered ploughings and 3-7 bullock-drawn passes of a heavy timber (ladder) to break soil clods. Rice and wheat seeds are invariably broadcast, before the last pass of the plough and the ladder. The area of rice-wheat cropping9 expanded considerably during 1960 to 1985, but has remained roughly constant since Yields in these sequences in recent years, and averaged over all Bangladesh5,8, have been about 2.1 t/ha of rough (Aus) rice, 3.4 t/ha of (rough) Aman rice, and 2.6 t/ha of unmilled wheat grain. There are indications 10 that wheat yields less when it is grown in previously puddled soil (after rice) than when it is grown in non-puddled soil (after non-rice crops or fallow). The extensions (since 1960) of ricewheat zones, and associated increases in productivity, were made possible by the development of short-duration photoperiod- 2

10 insensitive rice and wheat cultivars, by expansion of irrigation and fertilization, and by improvements in soil and crop management 11. They were made necessary by increases in population and food requirement and by the lack of unused farm land, which dictated that increased production would need to be derived from intensified use of land already under cultivation. Rice and wheat are indeed important components of the Bangladesh food requirement Trends during in the productivities of these two cereals - whether grown in sequence or otherwise - are shown in Figure 1. The productivities are presented as national averages in t/ha of rough rice or wheat grainl2,13,14. The influences (on the yield trends) of large year-to-year variations - perhaps resulting from extremes of weather or pest outbreaks - are lessened by the representation of a particular year's yield by its five-year moving mean: thus the wheat yield shown for 1963 was calculated as the average for the years 1961 through 1965, and for 1964 as the average for 1962 through Figure 1 shows that average rice yield increased progressively from 1.3 to 1.7 t/ha during the 1950s, remained at 1.7 t/ha during the 1960s, and (with modern cultivars and increased fertilization) increased steadily during and rapidly during to its current 2.5 t/ha. Wheat yield increased steadily from 0.6 to 0.9 t/ha during and (with increased fertilization and modern cultivars) rapidly during and more steadily during to a maximum (fiveyear moving mean) of 2.1 t/ha; it then decreased dramatically to 1.7 t/ha during The peak yield of 2.1 t/ha in part reflects an anomalously high 2.3 t/ha yield in 1984 achieved as a response to a severe loss in the preceding rice; but the subsequent continuous yield decline may be due partially15 to some of the better wheatlands (and their irrigation) being used for Boro rice or left unused in order to have a prompt establishment of an irrigated Aus rice; both Boro and Aus rice generate more profit than wheat (for which farmers perceive prices as too low). PROCEDURES OF MAP-MAKING The components of the rice-wheat database that are presented in this Bangladesh atlas are concerned primarily with magnitudes and time-trends in areas of rice, wheat, and ricewheat, and in the relationships of production to human population. Although analyses of the causes of these trends and relationships are beyond the scope and objective of this atlas, such analyses by appropriate specialists may nonetheless be assisted by a future augmentation of the database to include quantitative information on agricultural infrastructures, irrigation/hydrology, climate, soils, agricultural inputs, farm enterprises, and farm households. Maps and statistics in this current atlas are aggregated and interpreted at greater district 3

11 Yield (t/ha) 3.o.--~~~~~~~~~~~~~~~~~~~~-----, 2.0 Rough rice 1.0 Wheat grain o.o... ~~~~---~~~~~,_._~~~~---~~~~---'--i Median Year Figure 1. Progressions during for national average yields of rice and wheat in Bangladesh. Data presented as five-year moving means (e.g. displays for 1966 are means for 1964 through 1968) - thus lessening within the trends the effects of high year-to-year variability. 4

12 level. Procedures to assemble the database and maps - in particular to estimate the area for the rice-wheat sequence - were therefore developed to be suitable for use with published statistics aggregated at greater district level for the individual years 1960 through The various statistics were obtained from Statistical Yearbooks of Bangladeshl2, Yearbooks of Agricultural Statistics 13, and the 1990 Revision of World Population Prospects 16. A base map of the greater district boundaries was captured electronically using the Atlas*Pro mapping system and a Macintosh-Plus computer; this system was used also to process and display the data, and to create the corresponding maps. Estimates for each greater district for changes over time in areas or productions of rice, wheat, or rice-wheat (or in the ratios of productions to population) were determined as differences between the corresponding statistics in later and earlier years. To ensure that these differences would not be distorted by a chance choice of years with unusually high or unusually low values for area or production, the differences were calculated between statistics averaged over three consecutive years - usually three early years and three late years of the data series. The maps of areas and productions of rice and wheat in Bangladesh are thus presented for the two three-year sequences and The area of rice-wheat in each greater district in a particular sequence of years (e.g ) was estimated as 0.85 times the smaller of the greater district's calculated rice area or wheat area averaged for those three years. The fraction 0.85, derived from surveys and enquiries in Bangladesh and other countries of South Asia, is believed to be a realistic representation for all of Bangladesh. The remaining 0.15 fraction is an estimate for the proportion (of the smaller of the crop areas) that is used for jute, fodder, oil crops, or other purposes. The ratio of rice-plus-wheat production to human population in a particular greater district in a sequence of farming years (e.g , , ) was calculated as the sum of the greater district's average productions of rice (1960, 1961, 1962) and wheat ( , , crops) divided by the greater district's human population (1960). Because the farming years selected for mapping those ratios were not population-census years, the estimates for population were derived from projections of census enumerations made closely before or after the chosen year. In all the maps in this atlas, the statistics - whether of crop area, production, human population, or derived variables, and whether for specific years or changes over time - are displayed as single values for an entire greater district. In most maps, the statistics are represented by a particular intensity of shading. For a few variables - such as humanpopulation number and change - the statistics are displayed for an entire greater district as an assemblage of dots, with each dot representing a specific amount of the concerned variable (e.g. 100,000 persons). The distribution 5

13 of dots or circles within a greater district is random : it does not indicate any local concentration or sparsity of the displayed property. THE MAPS AND THEIR INTERPRETATION The nineteen maps of this atlas collectively display the areas of rice and wheat and of the rice-wheat sequence (and the trends in those areas during the three decades ) in the 21 greater districts of Bangladesh. lbey show also the distribution and change in human population, and the extent to which for each greater district the production of rice plus wheat per resident person has or has not been maintained or increased through those three decades (which saw more than a doubling of the Bangladesh total population). We here make brief commentary to help interpret the various individual maps, and where appropriate make reference to and comparison with other published sources. Map 1 is the base map for the analyses and database; it indicates names and boundaries of the various greater districts. Maps 2, 3, and 4 show the harvest areas of rice in and and the changes between those two sequences of years. In , total harvest area of rice was 8. 7 Mha, of which almost one half was contributed by 6 of the 21 greater districts - Barisal, Comilla, Faridpur, Rajshahi, Rangpur, and Sylhet However, the harvest-area total includes a substantial contribution from areas of land that had two rice harvests per year during The physical riceland-area total in was about 6 Mha. By , the harvest area of rice had increased by 1.6 Mha (18%) to 10.3 Mha, of which Rangpur and Sylhet each contributed more than 0.8 Mha. The harvest-area total (similarly to the total) includes a substantial contribution from land that grew more than two rice crops per year. The physical riceland-area total in was about 7 Mha; the Bangladesh total of arableplus-permanently cropped land in 1988 was 9.3 Mha 14. The map of change in rice-harvest area shows that the largest increases were in Dinajpur, Noakhali, and Rangpur. Rice-harvest area decreased during in the greater districts of Comilla, Dhaka, Pabna, and Rajshahi. The wheat area (Maps 5, 6, and 7) was only 0.06 Mha in , during which years only Rajshahi and Rangpur among the 21 greater districts had more than 0.01 Mha of wheat By , the wheat area was nine times larger than in , extending to 0.58 Mha; the increases in area (Map 7) were greatest in Comilla, Dinajpur, Jessore, Pabna, and Rangpur. For all of Bangladesh in , the total area of wheat was about one-twelfth of the physical area of riceland, and about oneeighteenth of the rice-harvest area. Estimates for the rice-wheat-sequence area are shown in Maps 8 and 9. The rice-wheat 6

14 area for all of Bangladesh in was estimated as only Mha, representing 1 % of the physical area of riceland and 85% of the total area of wheat Among greater districts, rice-wheat area approached or exceeded Mha only in Faridpur, Pabna, Rajshahi, and Rangpur. By , rice-wheat area was 0.50 Mha, some nine times larger than in The greater districts of Comma, Dinajpur, and Rangpur each had more than 0.05 Mha of rice-wheat cropping, and Faridpur, Pabna, and Rajshahi each had between 0.04 and 0.05 Mha. As a proportion of the individual rice and wheat areas in Bangladesh in , the 0.50 Mha of rice-wheat includes 7% of the physical area of riceland and 85% of the wheat area. Map 10 shows changes in rice-wheat area between and Increases larger than 0.05 Mha occurred in Comma, Dinajpur, and Rangpur, and of Mha in Dhaka, Faridpur, Jessore, Kushtia, Pabna, and Rajshahi. Maps 11 and 12 show for and the fraction of the total land area of each greater district that was devoted to the ricewheat sequence. In , the fractions approached or slightly exceeded 1 % only in Faridpur, Kushtia, and Pabna. For all Bangladesh, rice-wheat systems occupied 0.4% of total land area, and 0.6% of the total of arable plus permanently cropped land. By , the proportion of total land area allocated to ricewheat sequences approached or exceeded 5 % in nine greater districts, exceeding 8% in Comilla, Dinajpur, and Pabna, and attaining 11 % in Kushtia. For Bangladesh as a whole, the 0.50 Mha of rice-wheat systems in represented 3.5% of the total land area, and 5.4% of the total of arable plus permanently cropped land - a quite appreciable proportion. Changes between and in the percentage of land used for rice-wheat cropping are shown on Map 13. They were calculated as the percentage for minus the percentage for , and expressed as a percentage fraction of the percentage value. Thus, in greater districts (the majority) where the rice-wheat proportional area was small, a large percentage change could derive from a modest increase or decrease in the actual area (ha) of rice-wheat. Large increases are indeed seen for many greater districts : more than half of the 21 greater districts showed a percentage increase of 1000% or more, indicating that rice-wheat area increased more than ten-fold during For all of Bangladesh, the aggregate change (as was remarked in the commentary on Maps 8 and 9) was a roughly eight-fold increase in the proportion of land devoted to rice-wheat, corresponding to a compound increase rate of 8.6% per year. Maps 14, 15, and 16 show greater district totals for human population in 1960 and 1990, and the changes (increases) between those years. The total Bangladesh population increased by 110% during , equivalent to an annual compound increase rate of2.6%. The relationship to human population of rice-plus-wheat production (whether production 7

15 derived from the rice-wheat sequence or otherwise) is shown for and in Maps 17 and 18. The relation (ratio) for each greater district and year-pair was calculated as kg/year of rice-plus-wheat production per resident person. A negative change in that ratio over time would indicate that production of riceplus-wheat (for a greater district or for all of Bangladesh) had not been able to achieve that needed to maintain production per person as population grew, and that in order to sustain or improve nutrition there was need to import rice and wheat into districts and internationally. To estimate the annual per caput production of rough-rice-plus-wheat grain needed to satisfy the milled-rice-plus-wheat component of the per caput nutritional requirement (averaged for all of Bangladesh), we assumed Bangladeshi persons to have an average mass (weight) of 50 kg (males) and 45 kg (females), and to live at an annual mean air temperature of C. This results in an estimated calorie requirement 17 (as distinct from a calorie supply, which may be less) of 1900 calories per person per day (or 1900 cavcap.d). We further assumed that about four-fifths of this requirement3,18 (1500 cal/ cap.ct) might be supplied by rice-plus-wheat Assuming a 20% loss of production to wastage and pests, this 1500 cal/cap.ct is approximately the calorific food value of the polished grains or milled wheat flour from 300 kg/cap.yr of rough rice or wheat grain. In (Map 17), out of 21 greater districts, only three (Barisal, Dinajpur, and Kishorganj) met this 300 kg/cap.yr requirement. An additional five greater districts produced between 250 and 300 kg/cap.yr. However, of this total of eight greater districts, only Rajshahi had an appreciable area of rice-wheat cropping in The all-bangladesh-average production/caput in was 234 kg/cap.yr. By , when population was more than double that of , three greater districts (Bogra, Kishorganj, and Patuakhali) were able to produce at least 300 kg/cap.yr of rough-riceplus-wheat grain (Map 18). An additional three greater districts (Dinajpur, Jamalpur, and Rangpur) each produced between 250 and 300 kg/cap.yr. Among those six greater districts, Dinajpur and Rangpur both had more than 0.05 Mha of rice-wheat cropping in Map 19 shows that for all Bangladesh there was between and a decrease from 234 to 209 kg/cap.yr of roughrice-plus-wheat grain a decrease of 25 kg/cap.yr or 11 % of the value. Among the 21 greater districts, no fewer than 14 showed a decrease in rice-plus-wheat production during Moreover, decreases exceeded 100 kg/cap.yr in three greater districts - though none of those three had an appreciable area of rice-wheat systems in Conversely, seven greater districts increased their production per caput during , but among them, only Rangpur was a major practitioner of rice-wheat cropping. However, though the national-average production/caput of rice-plus-wheat in (at 209 kg/cap.yr) was substantially less than in (at 234 kg/cap.yr), that comparison is 8

16 not able to reveal that the decrease in production/caput was essentially completed by 1979, and that during the 1980s the production/caput was constant9, with rice-plus-wheat total production increasing at the same rate as population. Thus during , the annual rate of increase of rice production (for all Bangladesh) was 3.1 % (compared to 1.8% during ), but wheat production decreased at 2.6%/yr (compared to an 18%/yr increase during ). Rice-plus-wheat production during increased at 2.8%/yr9, and during at 2.1 %/yrl8, compared to a rate of population increase of 2.7%/yr. 9

17

18 THE MAPS 11

19 26'N 88'E Map 1 Names and Boundaries of the Greater Districts of Bangladesh 92'E Sylhet Kho Ina 22'N 88'E 90'E Huke - IRRI 1993 This base map shows the boundaries of the greater districts of Bangladesh. The same boundaries are shown in each of Maps 2 through 19. The base map has been purposely placed on a left-hand page so that it may easily be viewed in conjunction with any of the following maps. I 200 kilometers 12

20 Map2 Area Sown to Rice : Huke-IRRI 1993 Total harvest area of rice, averaged for 1960 to 1962, was 8.7 Mha. Almost one-half of this total was contributed by just six of the twenty-one greater districts. However, harvest-area total includes a substantial contribution from areas of land that had two rice harvests per year. Physical riceland-area total in was about 6 Mha. (The number of greater districts having a riceharvest area within each chosen class is specified within the caption: thus three greater districts had between 0.4 and 0.5 Mha.) Rice Area (OOOha) 50 to to to to to to

21 Map3 Area Sown to Rice : Huke-IRRI 1993 Rice Area (000 ha) 1 D 50 to D 200 to III 300 to ltlllllh 400 to 500 7Bf l1jd 500 to to 1000 During 1987 to 1989, total harvest area of rice was 10.3 Mha. Rangpur and Sylhet each had more than 0.8 Mha of rice cultivation. However, harvest-area total includes a substantial contribution from areas of land that had two rice harvests per year. Physical riceland-area total in was about 7 Mha. 14

22 Map4 Rice Area Change : t<;> Change in Rice Area (000 ha) to to 0 0 to to to to to 300 Between and , total harvest area of rice increased by 1.6 Mha (18% of the value). Largest increases occurred in Dinajpur, Noakhali, and Rangpur. Rice-harvest area decreased in four greater districts. However, harvest-area totals include substantial contributions from areas of land that had two rice harvests per year. Physical riceland-area total increased by about 1 Mha between and

23 Map5 Area Sown to Wheat : Huke-IRRI 1993 Wheat Area (OOOha),, 2_D..., 14 f 1 O to to10 2 LI 10 to 20 negligible wheat 0 m 20 to 40 o II 40 to so Total wheat area, averaged for 1961 to 1963, was only 0.06 Mha. Among the 21 greater districts, only Rajshahi and Rangpur had more than 0.01 Mha of wheat. 16

24 - Map6 Area Sown to Wheat: Wheat Area (000 ha) 0 to 5 5 to to to to 80 During 1988 to 1990, total wheat area was 0.58 Mha. Comilla, Dinajpur, and Rangpur each had more than 0.06 Mha of wheat. 17

25 Map7 Wheat Area Change: to Huke-IRRI 1993 Change in Wheat Area (000 ha) to to 0 0 to 5 5 to to to to 80 Between and , total wheat area increased by 0.52 Mha, and was thus nine times larger in than in The largest increases were in Comilla, Dinajpur, Jessore, Pabna, and Rangpur. 18

26 Map8 Rice-Wheat Sequence Area HUKE - IRRI 1993 Rice-Wheat Area : (000 ha) 10 I I 61 : : : :I 5 IA@:>] od od od od od 0 to 1 1 to 5 5 to to to to to to 60 During , total area for rice-wheatsequence cropping is estimated to have been only 0.05 Mha. Rice-wheat area approached or exceeded Mha only in Faridpur, Pabna, Rajshahi, and Rangpur. 19

27 Map9 Rice-Wheat Sequence Area HUKE - IRRI 1993 Rice-Wheat Area: (000 ha) 0 to 1 1 to 5 5 to to to to to to 60 During , total area for ricewheat-sequence cropping is estimated to have been 0.50 Mha. Six greater districts had more than 0.04 Mha of rice-wheat systems, among which Comilla, Dinajpur, and Rangpur each had more than 0.05 Mha. 20

28 Map 10 Rice-Wheat Sequence Area Change to HUKE-IRRI 1993 Change in Rice-Wheat Area to (000 ha) -1 to 0 0 to 1 1 to 5 5 to to to to to 60 Between and , the area of rice-wheat-sequence cropping increased by 0.44 Mha, and was thus nine times larger in than in Increases exceeded 0.05 Mha in Comilla, Dinajpur, and Rangpur. 21

29 Map 11 Rice-Wheat as Fraction of Land Area Percentage of Land Area in Rice-Wheat I I 4L od I od 2 Eilll 0.0 to to to to to 2.0 During , the proportion of total land area allocated to rice-wheat sequences approached or exceeded 1 % only in the greater districts of Faridpur, Kushtia, and Pabna. For all Bangladesh, rice-wheat systems occupied 0.4% of total land area, and 0.6% of the total of arable plus permanently cropped land. 22

30 Map 12 Rice-Wheat as Fraction of Land Area Percentage of Land Area in Rice-Wheat to to to to to to 20.0 In , the proportion of total land area allocated to rice-wheat sequences exceeded 5% in nine greater districts; it exceeded 11 % in Kushtia. For Bangladesh as a whole, rice-wheat systems occupied 3.5% of total land area, and 5.4% of the total of arable plus permanently cropped land. 23

31 Map 13 Rice-Wheat Area Proportional Change to HUKE - IRRI 1993 Percentage Change in Rice-Wheat Area to &1-0.1 to [:=:J 0.0 to D o.5 to ktr='='=?t/] 1.0 to Efill 2.0 to B 3.0 to 6.0 Between and , the proportional change in rice-wheat-sequence area, expressed as a percentage of the value, exceeded 1000% (that is, increased more than 10-fold) in twelve greater districts. Large percentage changes could result where the area was relatively small. 24

32 I ~ i I ' I I Map 14 Population Distribution : 1960 I.. Huke-IRRI 1993 I I Distribution of Human Population 1960 Each dot represents 100,000 persons Population total for all Bangladesh in 1960 was 54 million persons. 25

33 Map 15 Population Distribution : 1990 ~... I >,. Huke-IRRI 1993 Distribution of Human Population 1990 Each dot represents 100,000 persons Population total for all Bangladesh in 1990 was 113 million persons. 26

34 Map 16 Population Increase: 1960 to 1990 I "' Huke-IRRI 1993 Change in Human Population 1960 to 1990 Each dot represents 100,000 persons Between 1960 and 1990, population total for all Bangladesh increased by 58 million persons. Population in 1990 was 2.1 times larger than in

35 Map 17 Rice + Wheat Production per Caput : Huk:e-IRRI 1993 Production of rice-plus-wheat - whether grown in sequence or otherwise - amounted to 234 kg per year per caput of population (for all of Bangladesh) during (that is, in farm years , , and ). Among rice-wheat-practising greater districts, production per caput ranged from 200 to 300 kg/yr. Three greater districts produced more than the notional caloric requirement for rice-plus-wheat which is estimated to be 300 kg/cap/yr. But none of those three greater districts had appreciable area of rice-wheat cropping in Rice + Wheat per Caput : (kg per year) 2 D 50 to C::J 150 to li ':\:ti 200 to MHttttl 250 to B 300 to II 400 to

36 Map 18 Rice + Wheat Production per Caput: Production of rice-plus-wheat - whether grown in sequence or otherwise - amounted to 209 kg per year per caput of population (for all of Bangladesh) during (that is, in farm years , , and ). Among rice-wheat-practising greater districts, production per caput ranged from 100 to 350 kg/yr. Three greater districts (out of 21) produced more than the notional caloric requirement for rice-plus-wheat which is estimated to be 300 kg/cap/yr, but none of these greater districts had an appreciable area of rice-wheat cropping in However, Dinajpur and Rangpur, which did have substantial areas of rice-wheat, produced more than 250 kg/cap/yr. Rice + Wheat per Caput : (kg per year) 1 D 50 to 1so 8 1- : -: =- =- =- :I 150 to l=t::= i d 200 to mrrrn 250 to Bii 300 to to

37 Map 19 Rice + Wheat Production per Caput Change to Huk:e-IRRI 1993 Change in Rice + Wheat per Caput to (kg per year) -200 to to 0 0 to to to 300 Between and , the per caput production of rice-plus-wheat (whether grown in sequence or otherwise) decreased such that production per caput of the all-of-bangladesh population fell by 25 kg/cap/yr. Decreases in production per caput occurred in 14 out of the 21 greater districts. Seven greater districts increased their production per caput, but among them, only Rangpur was a major practitioner of rice-wheat cropping. 30

38 - REFERENCES CITED 1. Huke R, Huke E (1992) Rice/wheat atlas of South Asia. Draft publication. International Rice Research Institute, Los Banos, Philippines. 50 p. 2. Hoque M Z, Hobbs P R (1981) Rainfed cropping systems: Report of research findings at Brogra Village Publication No. 46. Bangladesh Rice Research Institute, Gazipur, Bangladesh. 3. IRRI - International Rice Research Institute (1993) IRRI rice almanac. IRRI, Los Banos, Philippines. 4. Saunders DA (1990) Report of an on-farm survey: Dinajpur District: Farmers' practices and problems, and their implications. Monograph No. 6. Bangladesh Agricultural Research Institute: Wheat Research Center, Dinajpur, Bangladesh. 39 p. 5. Saunders D A (1991) Report of an on-farm survey: Jessore and Kushtia: Wheat farmers practices and perceptions. Monograph No. 8. Bangladesh Agricultural Research Institute: Wheat Research Center, Dinajpur, Bangladesh. 30p. 6. Razzaque M A (1980) New research information on wheat. Pages 4147 in Proceedings of Workshop on Modem Rice Cultivation in Bangladesh. Publication No. 48. Bangladesh Rice Research Institute. Gazipur, Bangladesh. 7. Islam MR, Ahmed N U, Bhuiyan AM, Alam M M, Ghani M U, Quddus M A, Islam M T (1992) Diagnostic analysis of rice- wheat systems research at Chuadanga site in Bangladesh. Paper presented to Workshop on Methods of Measuring Productivity and Sustainability lbrough Farm Monitoring. International Maize and Wheat Improvement Center, Lisboa, Mexico. 32 p. 8. Meisner C A (1992) Report of on-farm survey of the Mymensingh Region and Tangail Wheat growers' practices, perceptions and their implications. Monograph No. 9. Bangladesh Agricultural Research Institute: Wheat Research Center, Dinajpur, Bangladesh. 31 p. 9. Woodhead T, Huke R, Huke E (1993) Areas, locations, and ongoing collaborative research for the rice-wheat systems of Asia. Communication to Regional Expert Consultation on the Sustainability of the Rice-Wheat Production System in Different Agro-Ecological Settings in Asia. PAO/RAPA, Bangkok, Thailand. 30p. 10. BRRI - Bangladesh Rice Research Institute (1992) Annual report for Publication No. 98. BRRI, Gazipur, Bangladesh. 11. Ahmed N U (1992) A review of BRRI cropping systems research Publication No Bangladesh Rice Research Institute, Gazipur, Bangladesh. 173p. f 31

39 12. Statistical yearbook of Bangladesh (Annual) Bangladesh Bureau of Statistics, Ministry of Planning, Dhaka, Bangladesh. 13. Yearbook of agricultural statistics (Annual) Bangladesh Bureau of Statistics, Ministry of Planning, Dhaka, Bangladesh. 14. AGROSTAT (Annual) Information system of The Food and Agricultural Organization (FAQ), Rome, Italy. 15. Islam M N, Islam M S, Ghani M A, Bhuiyan SI (1991) Rice-wheat trade-off in the North Bangladesh Tubewell Project. Paper presented at a Workshop on Applied Research for Increasing Irrigation Effectiveness and Crop Production. Bangladesh Agricultural Research Council, Dhaka, Bangladesh. 16. UN - United Nations (1990) 1990 Revision of world population prospects. United Nations, New York, USA. 17. FAO - Food and Agricultural Organization (1990) Calorie requirements. FAO, Rome, Italy. 18. FAQ/RAPA - Food and Agricultural Organization - Regional Office for Asia and the Pacific (1992) Selected indicators of food and agriculture development in Asia Pacific Region FAO/RAPA Publication 1992/15. Bangkok, Thailand. 211 p. 32

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