‘Gher’ farming system of Bangladesh: a win-win strategy for agricultural development?
Basanta K Barmon Department of Economics, East West University, Dhaka, Bangladesh Sanzidur Rahman School of Geography, Earth and Environmental Sciences, University of Plymouth, UK
Address for correspondence Dr. Sanzidur Rahman Associate Professor in Rural Development School of Geography, Earth and Environmental Sciences University of Plymouth Drake Circus Plymouth, PL4 8AA Phone: +44-1752-585911 Fax: +44-1752-585998 E-mail:
[email protected]
November 2010
‘Gher’ farming system of Bangladesh: a win-win strategy for agricultural development?1 Basanta K Barmon Department of Economics, East West University, Dhaka, Bangladesh Sanzidur Rahman School of Geography, Earth and Environmental Sciences, University of Plymouth, UK Abstract The present chapter provides a detailed examination of the present status of ‘gher’ farming system, i.e., an integrated prawn-fish-rice joint culture, which is practiced widely in southwest region of Bangladesh. It is an efficient and diversified farming system that produces a staple food crop (rice and fish) in conjunction with a high value cash crop (prawn) and provides a range of social, economic and environmental benefits. Gher farming is already playing an important role in Bangladesh economy by earning valuable foreign exchange, increasing food production and providing employment opportunities. The system is potentially a win-win agricultural development strategy that positively contributes towards food security as well as promotes livelihoods of farmers associated with this farming system. However, to date, the diffusion of this system remains marginal in other parts of the country. This is because, a number of challenges, including weather (flood, drought and cyclone), prawn diseases, constraints related to prawn marketing, and social conflicts are inhibiting its expansion to other regions of the economy. In light of this comparative analysis of present status, we judge the future prospect of this farming system that can serve as a desirable strategy for agricultural growth and development in Bangladesh. Keywords: Prawn, fish, rice, integrated farming, food security, livelihoods promotion, Bangladesh. 1
This chapter heavily draws on materials presented in Barmon et al., (2006; 2008a; 2008b; 2009; and 2010) and Rahman et al., (2010).
1. Introduction The economy of Bangladesh is largely dependent on crop agriculture although aquaculture is gaining importance in recent years. Bangladesh is considered as one of the most suitable countries in the world for freshwater prawn (Macrobrachium rosenbergii) farming, because of its favourable resources and agro-climatic conditions. A sub-tropical climate and a vast area of shallow water bodies provide a unique opportunity for freshwater prawn production (Ahmed et al., 2008a). Within the overall agro-based economy in Bangladesh, M. rosenbergii farming is currently one of the most important sectors. During the last three decades, its development has attracted considerable attention due to its export potential. The freshwater prawn is a highly valued product for international markets; almost all prawns are therefore exported particularly to the USA, Europe and Japan (Ahmed et al., 2009; Islam, 2008). In 2007-08, Bangladesh exported 49,317 tons of prawn and shrimp 2 valued at US$415 million, of which 25% was contributed by prawn (DOF, 2009). Prawn marketing potentially provides economic returns and social benefits to thousands of rural poor. The total area under prawn cultivation, in particular, in Bangladesh is estimated to be around 60,000 ha (Khondaker, 2009). Most prawn farms (71%) are located in southwest Bangladesh, mainly Bagerhat, Khulna and Satkhira districts, with the remainder in the southeast region (Ahmed et al., 2008a). The practice of small-scale prawn farming in rice fields is widespread in southwest Bangladesh due to the availability of wild postlarvae and low-lying rice fields, a warm climate, fertile soil, and cheap and abundant labour. The most spectacular development of prawn farming has taken place in Bagerhat district, where thousands of farmers have converted their rice fields to prawn farms to accommodate profitable prawn culture. The innovation of prawn farming in rice fields, combined with high 2
The term ‘shrimp’ is used for species in the family penaeidae.
prices of prawn in the international market, and rice for household consumption, has led increasing numbers of farmers to convert their rice fields to prawn farms (Ahmed et al., 2010). Even though this farming system is on the rise largely in coastal areas, there is limited information on its relative profitability and associated impacts. Given this backdrop, the present chapter provides a detailed analysis of this farming system in comparison to the most commonly practiced farming system in Bangladesh, i.e., the year round modern varieties (YRMV) of rice farming system, also known as the ‘Green Revolution’ technology. The chapter proceeds as follows. The next section briefly describes the RPG farming system and the YRMV rice farming system. Section 3 presents the research methods including description of the study areas and the data. Section 4 presents the results. Section 5 provides an overview of the constraints and opportunities of expanding the RPG farming system. The final section concludes and draws policy implications. 2. ‘Gher’ and ‘Modern Rice’ farming system in Bangladesh 2.1 The ‘Rice-prawn gher (RPG)’ farming system The term ‘gher’ refers to the modification of a rice field to enable operation of three enterprises: prawn (principal enterprise), carp, and MV rice. The middle of the ‘gher’ is surrounded by high and wide dikes with canals dug at the inner periphery of the dikes. The whole area of ‘gher’ is filled with rain-water during monsoon season, specifically from June to December, and closely resembles a typical pond. The ‘gher’ becomes dry naturally from January to April except the canals. [INSERT FIGURE 1 HERE]. A typical ‘gher’ cycle begins in May when farmers release freshwater prawn (M. rosenbergii) postlarvae into the ‘gher’. Farmers use lime during ‘gher’ preparation to reduce soil acidity. During the growing period, farmers provide supplementary feed to the prawn.
Traditionally, only snail meat was used as prawn feed, but nowadays farmers use a wide range of homemade and commercially available supplementary feeds to increase production. Before releasing prawn postlarvae (PL), farmers repair the ‘gher’ dikes and trenches almost annually. The carp fingerlings were also released into the ‘gher’ during May-June and are cultured for nine months or so (as long as sufficient water is retained in the ‘gher’). Usually, no specific supplementary feed is provided for the carps. Carps share the feed supplied to the prawns. Between January to April, farmers grow MV Boro rice on the land inside the ‘gher’, which is irrigated by water from the inside canals using either traditional methods (swing basket) and/or pumps. 2.2 The ‘Year-round Modern Variety (YRMV)’ farming system Currently three types of rice are produced in Bangladesh in three distinct seasons: aus (April to August), transplanted aman (T. aman) (August to December), and boro (January to April). Among them, aus and T. aman rice are produced under rainfed conditions and MV boro rice is produced in irrigated water (ground water or rivers and canals). Modern varieties of rice were introduced in Bangladesh for the boro and aus season in 1967 and aman season in 1970 (Hossain et al, 1990). In 2002, only 32% area was irrigated under MV rice production in Bangladesh, (BBS, 2002). Irrigation and chemical fertilizers are not generally used in local aus and T. aman rice production because the rice fields go under water. Farmers transplant MV boro rice from mid-January to mid-February, and harvest from mid-April to mid-May. Farmers usually use chemical fertilizers, pesticides, and irrigation for boro rice production. Along with rice crops, farmers also cultivate oil seeds, potato, and vegetables in the comparatively high land during the winter season. 3. Methodology 3.1 The study areas
The present research was conducted in Bilpabla, which is located about 7 km west from headquarter of Khulna district, and about 310 km south from the capital Dhaka. Bilpabla village was selected purposively because it is one of the typical villages in RPG farming. The demographic characteristics of the villages are very similar to other villages where RPG farming is practiced. Also, two year-round modern varieties (YRMV) of rice farming villages were purposively selected. These are Lebubunia and Chanchra village. Lebubunia village was selected purposely because the cropping pattern of Lebubunia was similar to Bilpabla village prior to the RPG farming system. Moreover, Lebubunia is the neighbor of Bilpabla village. The altitude level of rice fields in Lebubunia is slightly higher than the land for RPG farming in Bilpabla village. As a result, the farmers in Lebubunia village cannot convert their rice field into gher farms. The farmers in Lebubunia village mainly grow YRMV rice twice a year. The location of RPG farming (Bilpabla village) and YRMV rice farming (Lebubunia village) is exhibited in Figure 2. Twenty farmers were randomly selected from Lebubunia who mainly practice YRMV rice farming throughout the year. [INSERT FIGURE 2 HERE] Chanchra village is located in neighboring Jessore district which is about 60 km from Khulna district. The farmers mainly produce YRMV rice twice a year. One hundred farmers were randomly selected. Information collected include general information of the households, main inputs used such as chemical fertilizers, irrigation, pesticides, plowing, laborer, etc and outputs of MV rice produced throughout the year. The climate of the study area is of tropical monsoon-type with wide seasonal variations in rainfall, moderately warm temperatures, and high humidity. The rainy season formally starts from June to October when the monsoon air stream sweeps in from the Bay of Bengal. During this time, Bangladesh receives heavy rainfall and most places receive more than 2,538
mm with a wide range 1,937 to 2,949 mm of rain in 2001 (BBS, 2002). Khulna district annually receives, on an average, 1,696 mm with wide range between 1,159 to 1,994 mm. The average monthly humidity was 77%, which varies between 61% (March) and 84% (August) in 2001. However, the average monthly humidity was 79% with range between 66% (March) and 87% (July). The mean temperature was 270C in 2005 (BBS, 2002). RPG farming system, YRMV boro and local aman rice are the well adopted agricultural farming systems in Bilpabla, Lebubunia and Chanchra village. However, RPG farming is newer as compared to YRMV boro and local aman rice production. Before the RPG farming had started, the farmers in Bilpabla village produced only local aus and aman rice. On the other hand, the farmers in Lebubunia and Chanchra villages are now cultivating MV boro and aman instead of the traditional local aus and aman rice. 3.2 The farm surveys Several field surveys were conducted between 2006 and 2007. Farm survey methods, and data collection periods and procedures are presented in Table 1. The first survey was conducted from November to December in 2006. First, a census was conducted in Bilpabla village to collect the general descriptions of RPG farm households. Second, 90 RPG farmers were randomly selected from Bilpabla village and the basic information concerning main inputs and outputs of MV rice and prawn production as well as household income and labor demand was collected. To compare the main inputs and outputs of MV rice production, household income and labor demand of RPG farmers, 100 YRMV rice farmers were also randomly selected from Chanchra village. [INSERT TABLE 1 HERE] 3.3 Soil sampling and soil analysis methods In order to assess the impact of RPG farming system on soil quality of MV rice fields, the soil samples were taken from RPG and YRMV rice farming systems. A total of 40
farmers (20 farmers from RPG and 20 from YRMV rice farming) were randomly selected from two study villages. Each of the sampled 20 RPG and YRMV rice farmers belonged to 30 farm plots. Soil samples were collected first at the beginning of rice transplantation and second after harvesting of MV rice of both RPG and YRMV rice farmers of Lebubunia village who produced rice in 2005-06. Soil samples of YRMV rice farming of Chanchra village of Jessore were not collected because of time and resource limitation. Each sample of soil was a mixture of nine sub-samples collected from nine different places of a particular farm plot. The soils were taken at 0-15 cm depth, which represents the cultivated topsoil. After collecting soils, the sample soils were placed in polythene bags and well dried by natural sunshine. After drying, the soils were again placed in polythene and levelled numerically and sealed for transportation to the laboratory for testing. As the present study conducts to explore the impact of RPG farming on soil quality (fertility), therefore, the samples as well as plots number were identified with same numerical value at the beginning of rice transplanting and at the harvesting times of MV rice cultivation. Soils were dried in air, grinded, and sieved with 0.5 mm mesh. Some soil chemical properties were analyzed by routine methods; briefly, pH (H2O, 1:2.5), pH(KCl, 1:2.5), EC (1:5), total carbon and nitrogen by the combustion method (C-N analyzer, Sumigraph NC1000), exchangeable cations extracted with ammonium acetate, phosphorus absorption coefficient, available P by the Troug method, hot-water extractable NH4-N and B, available zinc and cupper extracted with 0.1 mol/L HCl and easily reducible Mn. The present study also collected various combinations of prawn feed that the farmers used in one prawn production cycle in 2005 through a farm records in order to explain the soil nutrient status of RPG farming. 4. Results and discussions 4.1 Impact of RPG farming system on the cropping pattern in the study villages
As mentioned earlier, three types of rice are produced in Bangladesh in three distinct seasons: aus (April to August), transplanted aman (T. aman) (August to December), and boro (January to April). Among them, aus and T. aman rice are produced in rainfed water and MV boro rice is produced in irrigated water (ground water or rivers and canals). Modern varieties rice was introduced in Bangladesh for the boro and aus season in 1967 and aman season in 1970. In 2002, only 32% area was irrigated under MV rice production in Bangladesh, (BBS, 2002). Irrigation and chemical fertilizers are not used local aus and T. aman rice production because the rice fields go under water. Farmers transplant MV boro rice from mid-January to mid-February, and harvest from mid-April to mid-May. Farmers usually use chemical fertilizers, pesticides, and irrigation for boro rice production. Along with rice crops, farmers also cultivate oil seeds, potato, and vegetables in the comparatively high land during the winter season. The cropping pattern of the study villages is presented in Figure 3. Before the advent of RPG farming in Bilpabla village, the farmers cultivated only local aus and broadcasted aus and aman rice in swampland and transplanted aman (T. aman) rice in the upper lands. The familiar broadcasted aus and aman rice has almost disappeared mainly because of siltation of inland rivers and canals, embankments of rivers, and environmental changes. Oil seed crops such as rape, mustard and sesame were also produced on the land with comparatively high altitude located along the riverside. The life cycle of broadcasted aman was longer than the broadcasted aus rice though the sowing time was same for both types of rice. The sowing time of aus and aman rice is in April/May and harvesting time is in August for broadcasted aus and December for broadcasted aman. The farmer sowed aus and aman seeds together in April/May because after June/July the whole area was go underwater due to heavy rain and at that times it was not possible to transplant aman (T. Aman). This production system of local aus and floating aman rice together was locally known as “Domuti”.
[INSERT FIGURE 3 HERE] RPG farming system has changed the cropping patterns dramatically in the study area (Figure 3). The construction of RPG farming has created opportunity for crop diversification. Along with prawn and fish, farmers can now cultivate MV boro rice on the mid-field and vegetables on the dikes of the gher mainly for home consumption. Prior to the RPG farming, farmers cultivated oilseeds such as rape, mustard and sesame after the harvest of local broadcasted aman rice however, the RPG farmers are not able to cultivate oilseeds due to physical construction of RPG farming. The RPG farming system has increased vegetables production compared to the past. The farmers have also planted fruit trees (coconut, mango, guava, jackfruit, banana, papaya etc.) on the dikes. The production period of prawn and fish start from May/June to December/January; MV boro rice from the end of January to end of April; and vegetables throughout the year. Farmers in Chanchra village usually practice YRMV rice farming because the farms are located in relatively high altitude level that are not possible to convert into RPG farming system like Bilpabla village in Khulna district. MV boro rice is produced during January to April followed by local variety T. aman rice during July to December. The cropping system of Chanchra village is also presented in Figure 3. 4.2 Impact of RPG farming system on soil fertility status of the rice fields 4.2.1 The physical and chemical properties of soils The chemical and physical properties of soils in RPG and YRMV rice farming are presented in Table 2. Soil pH The term pH refers to the alkalinity or acidity of a growing media water solution. Soil pH and base saturation are the important chemical properties that influence soil nutrient availability and plant growth and the activities of soil micro-organisms and organic matter
decomposition. All plants are not able to tolerate acidic or alkaline soils. Most of the field crops prefer neutral or slightly acidic soils because it promotes solubility of micro and macro nutrients for plant growth and development. Rice crops usually prefer slightly low acidic soils as compared to other crops. On average, the mean soil pH in rice field in RPG farming system at the beginning of transplanting and at the harvesting time of rice cultivation was 6.6 and 6.0, respectively. On the other hand, the mean pH in rice field in the YRMV rice at the beginning of transplanting and harvesting time of rice cultivation was 6.5 and 7.1, respectively. The mean pH of RPG farming has decreased after rice production, whereas, it has increased in YRMV rice farming after rice production. [INSERT TABLE 2 HERE] Electrical Conductivity (EC) Electrical conductivity (EC) is an important soil property related to salinity, and is often used for delineating other soil properties. EC measures the amount of total dissolved salts or the total amount of dissolved ions in the water. The mean values of EC at the beginning and at the end of MV production in Bilpabla and Lebubunia village is shown in Table 2. It appears from the table that the mean value of EC was low (71 Sm/m) at the beginning (December) of MV rice production under the RPG farming system, whereas, this value was more than twice (159 Sm/m) for YRMV rice production in Lebubunia village. However, the average value of EC at end of rice harvesting (April) was almost the same for both farming systems. This result indicates that under RPG farming system, the mid-rice fields are washed out at the beginning of transplanting due to prawn production. On the other hand, at the end of rice harvesting, the EC value has increased, which indicated that the salts have accumulated along with production in both farming systems. Thus it could be concluded that even though the salts accumulate in rice fields in RPG farming system, after prawn production the rice field escaped from the problem of salinity.
Cation Exchange Capacity (CEC) Cation exchange capacity (CEC) refers to the amount of positively charged ions of soil and it is a useful indicator of soil fertility. Because it shows the ability of soil’s important plant nutrients such as calcium (Ca++ ), magnesium (Mg++), potassium (K+), sodium (Na+) aluminium (Al+++), and ammonium (NH4+). In general, a soil contains more clay and organic matter (OM), which indicates its higher CEC. The CEC of soil in RPG farming was higher both at the beginning and at the harvesting of MV rice compared to YRMV rice farming, indicating that the soil in RPG farming system contains more clay and higher OM. In other words, the soil in RPG farming system is more fertile than that of the soil of YRMV rice farming. Total Carbon (C) Soil organic carbon is the biggest part of the soil organic matter (SOM) and it is considered as the most important indicator of soil quality and productivity. SOM affects a soil's structure, water storage capacity and nutrient supply. On average, the total organic carbon (C) in the soils of rice field in RPG farming system was almost four times higher than the YRMV rice farming system, which also indicates that the soils in RPG farming system were more fertile than YRMV rice farming system. Total Nitrogen (N) Nitrogen is a major component of proteins, hormones, chlorophyll, vitamins and enzymes essential for plant life. It is the most important soil element for crop production. The availability of optimal nitrogen for crop production influences the crop yields and deficiencies reduce yields. The nitrogen content of soils was also higher (more than three times) in the soils of rice fields of RPG farming compared to YRMV rice fields, which indicates that the soils in RPG farming system accumulate more nitrogen that enhance the land productivity as compared to YRMV rice farming.
Carbon Nitrogen (C/N) Ratio Carbon Nitrogen (C/N) ratio depends on the total C and N in the soils. C:N ratio of soils were almost same at the beginning of rice transplanting and at the harvesting of rice in RPG farming system. The C:N ratio was comparatively higher in the soils in RPG farming system than in the soils of YRMV rice farming system. This indicates that the RPG farming system has significant impacts on the soil fertility for MV rice production. Available Phosphorus Phosphorus is essential for plant growth. It is also necessary for seed germination, photosynthesis, protein formation and metabolism in plants. It is essential for flower and fruit formation. Deficiency symptoms are purple stems and leaves; maturity and growth are retarded. Yields of fruit and flowers are poor. Premature drop of fruits and flowers may often occur. In general total P content in soil varies the range between 200-1500mg/kg. In the study area, the P content is higher than the general P content level in the soil. The P content has decreased significantly after rice production. Base Saturation The percentage base saturation (BS%) is termed as the proportion of CEC satisfied by basic cations (Ca++, Mg++, K+, and Na+) and it is inversely related to soil acidity. In general, BS% increases when the pH of soil increases. The availability of nutrient cations such as Ca++, Mg++, and K+ to plants increases with increasing BS%. Base saturation is usually close to 100% in arid region soils. Base saturation below 100% indicates that part of the CEC is occupied by hydrogen and/or aluminum ions. Base saturation above 100% indicates that soluble salts or lime may be present, or that there is a procedural problem with the analysis. The base saturation (BS%) of soils in rice fields in the both types of farming system was above 100% at the transplanting and at the harvesting of rice. However, the BS% was lower
in the soils in RPG farming system than YRMV rice farming which indicates that more soluble salts existed in the soils of YRMV rice farming system than RPG farming system. 4.2.2
Quantity of nutrient concentrations of applied feed to prawn production The quantity of nutrient concentrations of applied feed to prawn production is
presented in Table 3. The present calculation was made based on per ha basis because the present study explores how much nutrient concentrations come from providing feeds to prawn production in 2005-06. It is noted that usually farmers supply feeds to prawn on the mid-rice field instead of canals because the prawns come onto mid-rice field of gher (locally known as chatal) in night for feeding. Therefore, the present study considers only the midrice field as a measurement of rice farm area even though some of the supplied feeds move from mid-rice fields to canal by prawns’ feeding nature. It appears from Table 3 that the meat of mud snails, fishmeal and legume grain (pulses) are the main sources of total nitrogen (TN), soil organic C (SOC), available phosphorus (AV), as well as other soil nutrients. The experimental results show that on an average, about 257 kg, 64 kg and 34 kg N, and 1,105 kg, 626 kg and 307 kg SOC, respectively, came from meat of mud snails, fishmeal and legume grain (pulses) that farmers applied in per ha prawn production in 2005/06 production cycle. It is not clear that how much leftover feeds remain on per ha of mid-rice field, and how much nutrients were gathered on the mid-rice field as prawn faeces. But it is believed that a large amount of nutrients accumulate on the mid-rice field that is not possible in YRMV rice farming system. As a result, the soils in RPG farming become more fertile owing to the leftover feeds of prawn production. [INSERT TABLE 3 HERE] 4.3. Profitability of RPG farming system 4.3.1 Characteristics of the farm scale Summary statistics of the farm sizes of the sampled farmers involved in the RPG and
YRMV rice farming is presented in Table 4. Table 4 shows that the average RPG farm was 4.09 bigha, and that the size varied from 1.0 bigha to 21.0 bigha. The average rice farm size of the Chanchra area was 3.14 bigha, with a range of 0.66 to 15.18 bigha. In Bilpabla the average size was 2.52 bigha, with a range of 0.50 to 15.0 bigha. Generally, in Bilpabla it can be assumed that about 50 to 70% of RPG farmland is used for MV rice production. [INSERT TABLE 4 HERE] 4.3.2
Costs, returns, and profitability of RPG farming system
As mentioned in the introduction, prawn and MV boro rice are the main products of the RPG farming system. In the early stages of RPG farming (1985-1995), farmers mainly used the meat of mud snails collected from small rivers, canals, swamplands and local ponds, as prawn feed. When the whole of the wetlands (swamplands) were converted into gher farming, mud snails gradually disappeared from these areas. Now farmers are applying various combinations of feed to prawns, on the basis of a trial-and-error method. The utilization of labor in agricultural sectors depends on many factors, such as cropping patterns, cropping intensity, potentiality of irrigation, and other intensive agricultural activities (Suryawanshi and Kapase, 1985). The green revolution has changed the agricultural land and labor productivity, and it has had considerable impact on labor demand and/or employment in developing countries. The adoption of new technology has substantially increased total agricultural employment, and has significantly contributed to the household income by increasing labor demand in developing countries (Estudillo and Otsuka, 1999). The diffusion of modern technology has increased the size of the labor market by increasing the demand for hired labor in Bangladesh (Hossain et al., 2000). However, Alauddin and Tisdell, 1995) argued that modern agricultural technology increased labor demand four-fold from the 1960s to the 1980s in the dry season, but the labor demand was stagnant in the wet season. The employment-generating effects of modern agricultural technology have slowed
down in recent years in Bangladesh. The green revolution has increased labor absorption at its early stage, but the labor absorption decreased in most developing countries after the adoption of the new labor-saving chemical and mechanical innovations (Jayasuriya and Chand, 1986). [INSERT TABLE 5 HERE] The RPG farming system has created more temporarily hired and permanently hired labor as well as family labor demand compared with the YRMV rice farming, in southwest Bangladesh. RPG farming is a labor-intensive farming system. Temporarily and permanently hired labor mainly depends on family labor (Barmon et al., 2004b; Rutherford, 1994; and Kendrick, 1994). Usually, family laborers and temporarily hired laborers are used for MV boro and aman rice production. Temporarily-hired laborers are employed on a daily basis at the prevailing market wage rate at the time of employment. The cost of items associated with the RPG farming system includes the cost of prawn and carp fish fingerlings, various kinds of feed, labor, medicine, watching house, rice and vegetable seed/seedlings, land preparation (bullock), irrigation, pesticides and fertilizers. Gross return of gher farming includes revenue from prawn, fish, rice and vegetables. The costs, gross revenue, and profit of RPG and the YRMV rice farming are presented in Table 5 (detail explanation is in Barmon et al., 2008). 4.4 Productivity of two main inputs in RPG farming system 4.4.1 The concept of water productivity In general, productivity is a measure of performance expressed as the ratio of output to input. Water productivity is defined as the ratio of per unit amount of grain yield to per unit water used in crop production. Depending on the water flows, water productivity can be defined as rice grain yield per unit water evapotranspired or grain yield per unit total water input including irrigation and rainfall (Bouman and Tuong, 2001). The numerator (output
derived from water use) can be defined in the following two ways- either physical output that can be total biomass or harvestable product or economic output that can be monetary value of output of agricultural production. The water input can be specified as volume (m3) or as the value of water expressed as the highest opportunity cost in alternative uses of the water. The economic output (monetary unit) is particularly convenient than physical output to measure water productivity when comparing different crops or different types of water use (Playan and Mateos, 2006). Water productivity can be increased by increasing yield and/or reducing water use. Bouman and Tuong (2001) showed that water productivity depends on water evapotranspiration. A wide variation of evapotranspiration reflects large variation of grain yield in the lowland rice production in the tropics. The yield also depends on the variety of germplasm of MV rice and production environments such as climate, soil characteristics, and production management. A large number of studies have been explained on water productivity on MV rice production on the basis of rain and irrigated water in tropical countries (Bhatti and Kijne, 1992; Bhuyan et al, 1995; Sandhu et al, 1980; Kitamura 1990; Misra et al, 1990; Khepar et al, 1997; Cabangon et al, 2002; and Dong bin et al, 2001). The present study considers monetary values of water usage in MV boro rice production because of the lack of data on total quantity of water usage in per unit MV boro rice production in YRMV rice farming system. Moreover, the evapotranspiration of water, outflows, runoff and leakage of water from MV rice field have ignored due to lake of data as well as for the sake of simplicity of the calculation of water productivity of MV boro rice production between RPG and YRMV rice farming. 4.4.2
Water Productivity and water-saving An attempt has been made to compare water use in MV boro rice production under
RPG and YRMV rice farming in this section. As mentioned earlier that only data on water
used in MV boro rice production are available. The secondary data of water used in per MV rice production in YRMV rice production were incorporated from other secondary sources (Hassal and Associates, 1998). Moreover, due to time and resource limitations, only water used in two rice fields of two RPG farmers were considered. In Bangladesh, usually the crop cycle of MV boro rice is 120 days. As a result, the water used in MV boro rice production in RPG farming system is calculated for 120 days and compared with secondary data on water consumption of MV rice production (Hassal and Associates, 1998). The water input used in MV boro rice production in RPG and YRMV rice farming is presented Table 6. The table shows that one an average, about 3,000 m3 and 10,368 m3 water used in per ha MV boro rice production in RPG and YRMV rice farming, respectively. In other words, about more than four times higher water requires for MV boro rice production in YRMV farming compared to RPG farming. [INSERT TABLE 6 HERE] 4.4.3
Factor shares, water and labour productivity of RPG farming system The factors share as well as water productivity of MV rice production under two
farming system are presented in Table 7. It appears from the Table 7 that the water input (irrigation) was higher in MV boro rice production in RPG than YRMV rice farming. Per ha grain yield is higher in RPG farming in comparison with YRMV farming, whereas, irrigation cost is significantly lower in MV boro rice production in RPG than YRMV rice farming. The water productivity of MV boro rice production was about 27 and 11 in RPG and YRMV rice farming, indicating that the water productivity was more than two times higher in RPG farming as compared to YRMV farming. In other words, water input was efficiently used in MV boro rice production in RPG farming compared to YRMV rice farming. [INSERT TABLE 7 HERE] 5. Constraints in expanding RPG farming system
The RPG system has also had significant impacts on the environment and ecology in Bangladesh (Kendrick, 1994; Kori, 1996; Ansary, 2000; Abedin et al 2000; Islam et al 2001; and Toufique 2002). 5.1 Impacts on the environment and ecology The RPG farming system has negative impacts on ecology. Fish diversity and fish catches has decreased in the swamplands, canals and rivers, because of the siltation or blockage of fish migration routes, water pollution as well as decreased swampland area due to gher construction (Abedin at et, 2000; and Islam, 2001). They concluded that indigenous fish are disappearing day by day, and some indigenous varieties have already become extinct. Along with indigenous fish, tortoise and frogs are also disappearing. Another study was conducted by Islam et al (2001) and concluded that fish availability is decreasing due to over fishing of Post Larvae (PL). The main input of prawn production – the mud snail has two direct significant negative impacts on ecology and human health. People have collected mud snails (Pila globosa) intensively from swamplands, canals and river to use as feed for prawn production; as a result, the mud snail has already disappeared in greater Khulna district. Now the farmer is importing mud snail from other districts as well as India. This unplanned intensive harvest of mud snail has negative impacts on ecology (Kendrick, 1994; Chowdhury, 1999; Dutta, 2001; and Islam, 2001). Dutta (2001) mentioned in his study that mud snails play an important role in wetland ecosystem and soil chemistry. Williams and Khan (2001) mentioned that the women and children who crush the mud snail for prawn feed suffer from skin irritations and respiratory complaints. In addition, the farmers often dump the shell of mud snails at the edge of roads or in nearby canals, thereby, polluting the local waterway and sometimes blocking the natural drainage system. However, recently this shell is being used as an input of poultry feed and lime. The grinding process of the shells creates a great deal of
dust that also causes respiratory problems for human health because the grinding mills are mainly located in residential areas (Barmon, 2006). 5.2 Impacts of RPG farming system on Livestock The impact of RPG farming on livestock is ambiguous. Kendrick (1994), Williams and Islam (1999) and Williams and Khan (2001) argued that livestock has decreased mainly due to unavailability of grazing land and unavailability of fodder crop. On the other hand, Barmon et al (2003) concluded that this farming system has a positive impact on livestock. Livestock and poultry have increased compared to shrimp gher farming. Before rice-prawn gher farming had started, landlords or rich farmers had a large number of cows and buffaloes and hired boys to take care of the cows but most of the small, landless and marginal landowners had no cow or some-times only owned a few in numbers. Livestock was not equally distributed among the people. Now, most are rearing more than two to three cows for milk and cow-dung. Instead of unavailable grazing fields, the gher farm owners’ as well as landless farmers collect feed (grasses) from embankments and store by-product of rice (straw) for cattle feed on gher embankments. The farmers usually use stored straw in the rainy season when feed is not available. 5.3 Land Tenurial Arrangement The RPG farming system has significant impacts on institutional change in land tenurial arrangement. The land tenurial arrangement has changed from traditional sharecropping to a fixed rent system after the introduction of the RPG farming system. The RPG farming system is a capital intensive enterprise and needs proper management for optimal production to protect virus disease as well as poaching of prawns. Moreover, the landlords and the tenants cannot predict the main output before harvesting. As a result, the land tenurial arrangement has converted from traditional sharecropping system to fixed rent system. The land rent depends on land productivity, distance from river, and altitude level.
The land rent has increased over the years because of larger participation of marginal and landless farmers as it is a profitable enterprise compared to rice farming. The landlords mainly engage in non-farm activities and a small portion of their total gher farm is operated mainly for home consumptions using permanent hired labor. Even though the RPG farming is a profitable enterprise, landlords do not operate total gher farm because permanent hired labor disrupt prawn production at every step. As a result, the landlords rent out gher farms to marginal and landless farmers on fixed rent agreement basis. The RPG farming system has redistributed the landholding patterns due to the participation of marginal and landless farmers. Some marginal and landless farmers became small landowners after the successful operation of RPG farming (Barmon, 2006). 5.4 Constraints of production and marketing system of prawn under RPG farming 5.4.1 Risk and Uncertainty of Prawn Production3 Risk and uncertainty are pervasive characteristics of agricultural production and play a significant role in the production choice, output, and its future market price. Risks and uncertainties are always associated with RPG farming. The main product of RPG farming is prawn, and the optimal production of prawn depends on several uncontrollable environmental conditions or factors such as adverse weather conditions (seasonal flooding, high temperature and draught), viral diseases and controllable factors such as feeding system, feeding types, and proper managements. But the natural risks such as optimal rain, higher temperature, flood and unknown viral disease are beyond the control of farmers and these factors, particularly viral diseases and higher temperature and draught (the leasing time of prawn fingerlings) seriously affect mortality rate of postlarvae as well as the yield of prawn. In addition, the feeding types and system also affect prawn production. Usually meat of mud snails is the main feed for optimal growth of prawn. Along with mud snail, the
3
This section has heavily drawn on Barmon (2004a).
farmers also use different types of home-made feed. As a result, the yield of prawn widely varies within the gher farming. In general if the natural risks such as viral disease and weather conditions are not severe and the farmers use meat of mud snails for prawn feed and take care properly the farmers get optimal production of prawn. The results of field surveys suggested that high risks and uncertainties are associated with rice-prawn gher farming; thus, the production is very erratic. 5. 4.2 Constraints in prawn marketing The main product of gher farming system shrimp/prawn is the second largest export item in Bangladesh and reached the international markets through a number of channels. Every channel receives a substantial profit, therefore, per unit market price of shrimp/prawn have increased in every channels. In other words, every segment of the channel have significant profit margin. The field survey showed that the commission agents receive only commission fee taka 20 for per shrimp/prawn sale to processors and exporters. Therefore, no financial risk involve in this segment of the marketing channel. Faria (traders) play very interesting role in the marketing channel, because sometimes, they buy per kg shrimp/prawn from farmers at local market price. However, they earn profit. They buy shrimp/prawn from farmers without grading or underweight or dry weight of shrimp/prawn at gher farming areas. After buying, they grade according to size of grading system, and keep shrimp/prawn into water of plastic containers or big aluminum pot for 1-2 hours. After absorbing water, weight of shrimp/prawn increases as compared to gher farming areas. Therefore, even though they buy shrimp/prawn from farmers at the same existing market price, they earn substantial profit from their trading. Processors and processors/exporters are the final segment of the marketing channel. As they invest a large amount of money in this trading system and a large number of financial risks are involved, they earn maximum profit from this marketing channel. Usually, the
exporters/processors export the shrimp/prawn in the markets of EU, USA and Japan through air freight and ship. Sometimes, the international company send back to the exporters because of proper packing, proper HACCP criteria etc. As a result, they face huge financial loss from this trading. Both backward and forward agents/actors are linked in the shrimp/prawn industry. The backward agents/actors play roles at the different points from fry collection from natural sources or hatcheries to selling farmers and the forward agents/actors play role from the different points from production to selling in international markets. The field survey reports that the agents/actors of the backward segments do not have any monopoly or monopsony power to set market price. The market price mainly depends on the availability of wild fry from natural sources as well as hatcheries. However, the agents/actors of the forward segments have monopoly and monopsony power to set market price. The middlemen of the forward segments named aratdar and faria set the market price to discuss with the other faria and aratdar in the same local market. Moreover a number of constraints those hinder smooth prawn marketing reported by farmers and traders, including poor road and transport facilities, higher transport costs, poor supply of ice, and lack of money for the business. In addition, poor electricity supply, labor unrest, and political disturbances (i.e., road blocks, strikes) also affect prawn marketing (Ahmed et al. 2009). 5.4.3 Social Status and Social Conflicts The RPG farming has both significant positive and negative impacts on the local societies. All participants in the RPG farming including farmers, local traders (faria and bepari), and agents, have improved their standards of living, social status, purchasing power, ability as an economic sector, food consumption, children’s education, health facilities, sanitation and drinking water supplies through tube-wells. However, local prawn traders have
gained more than the farmers. Traders have improved their social and economic conditions through prawn marketing. They have broadly improved their housing conditions, and profits are used to replace bamboo roofs and walls with tin sheets and wood. On the other hands, most of the prawn farmers did not improve their socioeconomic conditions due to lack of skills, poor education, inadequate financial support, and high interest loans from moneylenders (Ahmed et.al. 2010). The RPG farming has substantially improved food security in the locality. Prior to PRG farming, almost all poor farmers took food twice a day. Nowadays, they are able to eat rice three times a day and also eat better quality food, including fish, meat, milk, eggs, fruits and vegetables. Vegetables are now more abundant and are also cheaper as a result of dike cropping, and farmers have benefited from selling these. Most the farmers are enjoying fish (from gher), milk and eggs (rearing homestead), and fruits (from dike of gher) that were not possible in the past (Ahmed et. al. 2010; Barmon et al. 2006). The RPG farming has negative impacts on the local society as well. The RPG is a capital-intensive enterprise and a number of risks and uncertainty including disease, draught floods etc involved in prawn production. The poor and small farmers borrowed loans from local moneylenders, landlords and local traders with high interest rate at about 120% annually. Farmers often used their principal asset, land, as collateral. Sometimes they do not get good production of prawn due to lack of technical knowledge, uncontrollable flood, draught, disease etc. Consequently, they sell their piece of lands to landlords and moneylenders. As a result, many of them actually became poorer, or at least potentially more vulnerable. In some cases, rich farmers and wealthy people forced poor farmers to sell their land. Friction between the two sides sometimes led to scuffles involving villagers and hired enforcers employed by the wealthy. Some of the minority Hindu people feel insecure due to
conflict with Muslims, and a number have migrated to India, selling their land and prawn farms to others. The RPG farming has also disrupted social bonding (social process and system), increased sexual harassment, decreased rate of higher education in the locality. Usually poor women work in various activities of prawn production with male laborers. Moreover, mainly women are engaged in de-heading, icing, packing etc. and most of these operated at night. Sometimes, women sexually harassed by their counterpart male labour and depot owners. 6. Conclusions and policy implications (needs to be shortened and revised) RPG farming system is an indigenous technology solely developed by local farmers since the mid 1980s in southwest parts of Bangladesh. RPG was an advanced agricultural technology followed by “Green Revolution” in Bangladesh. The RPG farming is locally known as “White Revolution” and prawn as “White Gold”. RPG farming has significantly positive impacts on soil quality and land productivity as compared to YRMV rice farming system in Bangladesh. Soils of rice fields of YRMV rice farming is more salinity affected than that RPG farming. The main reason is that the rice fields under RPG farming are washed out every year during prawn production. The leftover feeds of prawn production provide a significant amount of soil nutrients such as nitrogen, soil organic matter, phosphorus, potassium and other nutrients to soils in fields for MV rice under RPG farming system. As a result, farmers in RPG farming used comparatively less chemical fertilizer for per ha MV rice production compared YRMV rice farming. Some farmers do not apply chemical fertilizer at all in rice fields in MV production even though the per ha yield is almost similar to other RPG farmers which also indicated that the soil quality as well as soil fertility has improved due to the leftover feeds of prawn. MV boro rice grain yield in per ha land was higher in RPG farming system as compared to the YRMV boro and aman rice production. Farmers have gained more agricultural income
(more than five times higher) as well as household income (more than double) from RPG farming as compared to YRMV boro and aman rice production in Bangladesh. The household income per capita in the RPG farming area is about double that of the YRMV rice farming area, and about four times higher than that of the people in rural Bangladesh. Therefore, it can be concluded that the RPG farming system has created a good production environment for MV rice farming. This farming system has also created employment opportunities both for hired and family labor, which has significant impact on household income. RPG farming has significantly positive impacts on water productivity for MV boro rice production compared to YRMV rice farming. Water input is also efficiently used in RPG farming than YRMV farming. Unproductive water runoff and/or water outflows are very small during irrigation times of crop growth period MV rice production in RPG farming than YRMV rice farming. Moreover, large-scale water is required for soaking of land preparation for rice transplanting in YRMV rice farming. As ground water is used in MV rice production, the rice fields were affected by sanilization. Preserved water that comes from rainfall and flooding in rainy season, used in MV rice production in RPG farming system. The rental contract agreement also changed from a variable sharecropping to a fixed rent system. Since more natural risks and uncertainties are involved in gher farming as compared to rice production, therefore, the land tenure system has changed from traditional sharecropping system to fixed cash system. A large number of value chain activities are involved in shrimp/prawn industry from production stage of shrimp/prawn to final exporting stage aboard. All segments of mud snail trading channel, fry trading channel, shrimp/prawn exporting channel as well as agro-based industry that established using shell of mud snails and legs of shrimp/prawn add a significant value chain. Male and female laborers, as well as children are engaged in various activities in
the trading channels in shrimp/prawn industry. Even though the farmers bear all the production risks, they did not get the profit like other agents of the marketing channels of shrimp/prawn industry. All agents of marketing channels gain more financial benefits than the producers of shrimp/prawn of Bangladesh. Nevertheless, after considering all the pros and cons of gher farming system, it can be safely concluded that the system has provided a largely win-win solution to the farming population and associated stakeholders and could be a desirable strategy to foster future growth of the Bangladesh agricultural sector.
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Islam, M.S., 2008. From pond to plate: Towards a twin-driven commodity chain in Bangladesh shrimp aquaculture. Food Policy, 33: 209-223. Islam, K.R., and R.R. Weil., 2000. “Land Use Effects on Soil Quality in a Tropical Forest Ecosystem of Bangladesh”. Agriculture, Ecosystems and Environment, Vol. 70, pp. 916. Jayasuriya, S.K. and R.T. Shand., 1986. “Technical Change and Labor Absorption in Asian Agriculture: Some Emerging Trends”. World Development, Vol. 14, pp. 415-428. Kendrick, A., 1994. “The Gher Revolution: The Social Impacts of Technological Change in Freshwater Prawn Cultivation in Southern Bangladesh”, The Report of a Social Impact Assessment Prepared for CARE International in Bangladesh with Support from the Bangladesh Aquaculture and Fisheries Resource Unit (BAFRU). Khepar, S.D., Sondi, S.K., Kumar, S. and K. Singh., 1997. Modeling Effects of Cultural Practices on Water Use in Rice Fields – A Case Study. Research Bulletin, Publication No. NP/SWE-1, Punjab Agricultural University, Ludhiana, India. Kitamura, Y., 1990. Management of an Irrigation System for Double Cropping Culture in the Tropical Monsoon Area. Technical Bulletin 27, Tropical Agriculture Research Centre, Ministry of Agriculture, Forestry and Fisheries, Tsukuba, Ibaraki, Japan. Khondaker, H.R., 2009. Prawn hatchery development in Bangladesh: problems and potentials. In: M.A. Wahab and M.A.R. Hossain (eds.), Abstracts – National workshop on Freshwater Prawn Farming in Bangladesh: Technologies for Sustainable Production and Quality Control, 9 July 2009, Dhaka, Bangladesh, p. 11. Mishra, H.S., Rathore, T.R. and R.C. Pant., 1990. “Root Growth, Water Potential, and Yield of Irrigated Rice”. Irrigation Science 17, 69–75. Nijera Kori., 1996. Profit by Destruction. International Workshop on Ecology, Politics and Violence of Shrimp Cultivation, 2/4, Block-C, Lalmatia, Dhaka-1207, Bangladesh.
Rahman, S., Barmon, B.K. Ahmed, N. 2010. “Diversification economies and efficiencies in a ‘blue-green revolution’ combination: a case study of prawn-carp-rice farming in the ‘gher’ system in Bangladesh” ‘Aquaculture International’ (in press). Rutherford, S, 1994. “CARE and Gher: Financing the Small Fry”, The Report Prepared for CARE International in Bangladesh with Support from the Bangladesh Aquaculture and Fisheries Resource Unit (BAFRU. Sandhu, B.S., Khera, K.L., Prihar, S.S. and B. Singh., 1980. “Irrigation need and Yield of Rice on a Sandy Loam Soil as Affected by Continuous and Intermittent Submergence”. Indian Journal of Agricultural Science, Vol. 50, No. 6, pp. 492–496. Suryawanshi, S.D., and P.M. Kapase., 1985. “Impact of Ghod Irrigation Project on Employment of Female Agricultural Labor”. Indian Journal of Agricultural Economics, Vol. 60, No. 3, pp. 240-244. Toufique, K. A. (2002). Community responses to environmental degradation due to shrimp aquaculture in Bangladesh. Bangladesh Institute of Development Studies (BIDS). Paper for presentation in the 9th Biennial Conference of the International Association for the Study of Common Property on the Commons in an age of Globalization to be held in Victoria Falls, Zimbabwe, 17-21 June. Williams, D., and S. Islam (1999). Study report on impacts of gher farming on agriculture and livestock. Greater options for local development through aquaculture (GOLDA) project,
CARE-Bangladesh.
Funded
by
the
Department
For
International
Development (DFID), UK. Williams, D., and N.A. Khan (2001). Freshwater prawn farming in gher systems: Indigenous technology developed in south-west Bangladesh. Greater options for local development through aquaculture (GOLDA) project, CARE-Bangladesh, GPO Box No. 226, Dhaka 1000.
Figure 3. Cropping patterns of the study villages Crops
Jan
Feb
Mar
Months April May June July
Aug
Sep
Oct
Nov
Dec
Bilpabla village (RPG farming) Before the introduction of RPG farming: Swampland: Broadcasting aus paddy Broadcasting aman paddy Rainfed upland: Aus paddy T. aman paddy Rape/Mustard/Sesame After the introduction of RPG farming: Prawn Fish MV boro paddy Vegetables Chanchra village (YRMV paddy farming) Before the green revolution Local aus paddy T. aman paddy After the green revolution MV aman paddy MV boro paddy Source: Adopted from Barmon, et.al., 2009a. Notes: indicates the period up until the sowing of paddy, and releasing of prawn and fish is carried out. indicates when the harvesting period starts. T. aman indicates transplanting aman paddy.
Table 1. Duration of farm survey and soil test experimental time of the present research study Particulars 1. Soil samples collection:
Farm survey and soil samples collection time First collection: December, 2005 (at the beginning of rice transplanting) RPG farming : 30 Samples of 20 RPG plots of Bilpabla village YRMV rice farming : 30 Samples of 20 YRMV rice farmers Lebubunia village Second collection: April, 2006 (at rice harvesting time) RPG farming : 30 Samples of 20 RPG plots of Bilpabla village YRMV rice farming : 30 Samples of 20 YRMV rice farmers Lebubunia village
Soil samples test:
Soil analysis time : October, 2006 to May, 2007
2. Farm survey:
RPG farming : Bilpabla village, Khulna district Number of RPG farming : 90 Farm survey time : April and October-December, 2006 YRMV rice farming : Lebubunia village, Khulna district Number of YRMV rice farming : 20 Farm survey time : April, 2006 YRMV rice farming : Chanchra village, Jessore Number of YRMV rice farming : 90 Farm survey time : October-December, 2006
3. Water measurement record Water measurement time : Every week 1 May 2006 to 30 April, 2007 Source: Adapted from Barmon, 2006.
Table 2. Some chemical and physical properties of soils in Bilpabla and Lebubunia Bilpabla Properties of soil pH(H2O) pH(KCl) ∆pH EC Total C Total N C/N ratio Exchangeable cation
(mS/m) (g/kg) (g/kg) Ca++ Mg++
(cmolc/kg)
K+ Na+ CEC Base saturation Cation ratio [based cmol] Available P (Troug) PAC 0.1 N HCl Hot H2O ext.NH4-N Easily reducible Mn Hot water ext. B Appar. specific gravity Abbreviations:
(cmolc/kg) (%) Ca/Mg Mg/K Ca/K (mg P/kg) (g P/kg) Zn Cu
(mg/kg) (mg/kg) (mg/kg) (mg/kg) (g/cm3)
Lebubunia
Dec. 2005
Apr. 2006
Dec. 2005
Apr. 2006
6.6
6.0
6.5
7.1
5.9 -0.8 71 78 6.1 13 43 12 0.9 3.8
5.5 -0.5 161 78 5.9 13 39 11 0.7 5.3
5.8 -0.7 159 21 2.0 10 25 10 0.8 3.4
6.5 -0.6 143 19 1.7 11 24 9 0.7 4.6
50 121 3.5 14
52 110 3.4 18
31 137 2.6 13
30 129 2.8 12
49 83 6.5 2.7 1.2 120 72 3.3
62 70 6.4 3.1 1.5 75 57 2.7
34 75 4.4 2.7 7.3 61 72 2.1
33 86 4.2 2.3 6.2 54 74 2.2
1.00
1.03
1.10
1.09
EC: electro conductivity CEC: cation exchange capacity PAC: phosphorus absorption coefficient Source: Adapted from Barmon, et.al., 2010.
0.03 15.08 1.17 2.74 0.66 1.89 0.27 8.18 11.19
0.60
64.83
8.21
33.62
6.32
9.80
4.18
10.77
257.43 41.3
(kg) 0.12
(kg) 0.44
396.2
P
N
Source: Adapted from Barmon, et.al., 2010.
Total element con.
Meat of mud snail
Wheat bran
Oil cake (soybean)
Oil cake (mustard)
Broken rice
Legume grain
Beaten rice (Chira)
Fish meal
Wheat noodles
Starter 1
Feed items
59.9
27.98
6.03
1.43
2.92
0.66
7.55
1.17
12.06
0.06
(kg) 0.06
K
230.3
193.07
0.86
0.27
1.20
0.00
1.37
0.00
33.17
0.00
(kg) 0.34
Ca
31.1
19.59
4.31
0.16
0.86
0.33
0.69
0.59
4.52
0.00
(kg) 0.04
Mg
3.6
0.59
0.37
0.05
0.25
0.20
0.34
0.04
1.77
0.00
(kg) 0.01
Fe
0.5
0.1000
0.1100
0.0030
0.0100
0.0100
0.0300
0.0100
0.2400
0.0003
(kg) 0.0010
Mn
0.6
0.3400
0.0500
0.0040
0.0100
0.0040
0.0300
0.0100
0.1100
0.0003
(kg) 0.0010
Zn
Cu
0.1
0.0500
0.0030
0.0010
0.0002
0.0010
0.0100
0.0010
0.0300
0.0001
(kg) 0.0002
Table 3. Element concentration of applied feed to prawn production in RPG farming in 2005-06 production cycle (Per ha basis)
76.3
5.60
7.75
0.27
1.72
1.00
2.74
1.17
55.78
0.00
(kg) 0.30
cr.Si
15.5
6.75
0.56
0.00
0.05
0.00
0.10
0.03
7.95
0.00
(kg) 0.07
Na
2758.8
1105.27
200.31
24.75
79.07
139.27
306.66
261.02
625.64
13.40
(kg) 3.38
C
2.52
Rice production area (bigha)
3.14
MV aman rice field (bigha)
Note: One bigha is equal to 0.5 acres or 0.2024 ha in the locality.
Source: Adopted from Barmon, et.al., 2008a.
3.14
MV boro rice field (bigha)
Year-round MV (YRMV) rice farming
4.09
Mean
Gher area (bigha)
Rice-prawn gher (RPG) farming
Farming systems
Table 4. Statistics of rice-prawn gher and year-round MV rice farming
15.18
15.18
0.50
21.00
Max
0.66
0.66
15.00
1.00
Min
2.63
2.63
2.12
3.23
SD
A. Variable costs 1. Prawn fingerlings 2. Carp fingerlings 3. Feed 4. Hired labor 5. Family labor 6. Medicine Sub total (A) MV rice production B. Variable costs 1. Seedlings 2. Land preparation 3. Hired labor 4. Family labor 5. Irrigation 6. Pesticidies 7. Fertilizers 8. Others Sub total (B) C. Fixed costs 1. Dep. of gher preparation 2. Monitoring house 3. Farm land 4. Land rent Total fixed cost ( C )
Prawn production
-
1,583 2,713 11,185 2,297 3,460 2,409 5,024 522 29,193 18,800 1,478 20,278
972 677 4,500 1,677 1,051 818 896 652 11,243 1,007 678 12,567 9,722 23,974
(Taka) -
Chanchra village
(Taka) 45,080 1,155 57,419 19,734 23,785 1,470 148,643
Bilpabla village
Table 5. Cost and returns of rice-prawn (RPG) and year-round MV (YRMV) rice farming system Gher farming MV rice farming Particulars
D. Total cost (A+B+C) 183,860 49,471 E. Revenue 1. Prawn 262,408 2. Fish 13,045 3. Rice 28,713 64,812 4. Straw from rice 2,719 9,051 5. Vegetables 403 Total Revenue (E) 307,288 73,863 Total Profit (E-D) 123,428 24,392 Source:Adapted from Barmon, et.al., 2008a. Notes: (1) Number of gher and MV rice farms sampled was 90 and 100, respectively. (2) Average gher and MV farm sizes were 4.09 bigha and 3.14 bigha, respectively. (3) One bigha is equal to 0.5 acres or 0.2024 ha in the locality. (4) 1 US$ = 72.65 Taka, December, 2006. (5) Depreciation of gher construction and the monitoring house was calculated by the straight-line method. In this method the depreciation is calculated by dividing the total expected depreciation value equally among the expected number years of the life of the gher (Hopkins and Heady, 1955). On the basis of the farm survey data, the economic life of gher farming was considered to be 25 years.
3411.99
RPG-2
1016.79
943.83
Water used (m3)
RPG farming
Note: Hassal and Associates (1998)*.
Source: Adapted from Barmon, et.al., 2008b.
3449.2
Area (m2)
RPG-1
Farms
2980.05
2736.37
Water used (m3)/ ha
Table 6. Water used in rice production under RPG farming
10,368
10,368
Water used (m3)/ha*
YRMV rice farming
3.45
3.79
Ratio
1,051 818 854 4,932 3,467 1,465 9,180
28,713
Irrigation
Pesticides
Chemical fertilizers
Total labor cost
Hired
Family
Total input cost
Total output (Taka) 0.03 0.02 0.04 0.03 0.03 0.17 0.12 0.05
Seeding
Land preparation
Irrigation
Pesticides
Chemical fertilizers
Total labor cost
Hired
Family
Factor Share:
677
Land preparation
0.00
0.18
0.18
0.10
0.04
0.09
0.04
0.02
36,946
17,232
93
6,549
6,642
3,582
1,375
3,344
1,392
897
Boro rice
Boro rice 878
YRMV rice farming
RPG farming
Seeding
Input costs (Taka):
Particulars
Table 7. Input costs, output and factor shares of MV rice production
5.82
Labor productivity
Source: Adapted from Barmon, et.al., 2008b. Note: US $ 1 is equal to 68.40 taka (December, 2007).
27.32
Water productivity
Productivity: 5.56
11.05
