Báo cáo khoa học nông nghiệp " REPORT ON BASELINE SURVEYS IN CANTHO AND AN GIANG PROVINCES " pdf

1 \ Ministry of Agriculture & Rural Development Project Progress Report CARD Project 023/06/VIE MS3: REPORT ON BASELINE SURVEYS IN CANTHO AND AN GIANG PROVINCES 24 th April , 2009 2 Baseline study had been carried out during October-November 2007 at Cantho city and during January-February 2008 at An Giang province to assess environment pollution from disposal of waste of catfish aquaculture ponds and implications for sustainable agriculture production. Two districts of Cantho city (O’Mon and Thot Not) and two districts of An Giang (Chau Phu and Phu Tan) were selected based on high numbers of fishpond present in these districts. Primary information relating to techniques, socio- economics and environment were recorded by interviews with farmer individually, and was supplemented by observations to evaluate or confirm data. This was followed by contact with local officers to collect secondary data as needed. Two groups of farmers were chosen (rice growing and fish raising groups) in equal numbers at each site. A total of 240 questionnaires were collected for data analysis. I. Socio-economics aspects Farmers practicing fishpond culture in Cantho are a little younger than those who carried out rice cultivation (43 compared to 49 yrs.); however, there were no difference in ages between these two groups in An Giang province (Table 1). In An Giang province, fish raising farmers were also rice growing farmers, who turned to the fish farming system in order to increase their income. By contrast, fish raising farmers in Can Tho are mainly migrants, who hired or bought land from local farmers which explains why the fish raising farmers are younger and with higher formal education level than rice growing farmers. Rice culture has long been practiced in the Cuu Long delta. Most of rice growing farmers have more than 20 years experience in rice farming. Meanwhile the freshwater fish industry has recently expanded. The data on number of years’ experience in fish culture clearly showed that this industry was developed during less than 10 years. The family size was not very much varied between two types of farming system. It is about 5 persons/family including a labour force of 3-4. Land tenure areas for rice farming in both Can Tho and An Giang are much higher than areas used for fish culture. The reason might be due to total cost for raising fish is much higher than rice farming (Table 1). Most of farmers in Cantho and An Giang had concrete or brick houses (80-90%). Thatch house cover less than 10% of rice farming but it is about 15-20% in the case of fish culture. Some fish raising farmers are migrants who stay on site temporarily to look after their fish. They also have permanent houses at other places. The Cuu Long delta has abundant of water that is why rice or fish culture mainly rely on canals or rivers as their water source. Survey data revealed that water pollution is a concern for 15-25% farmers. The evaluation of water quality between upper stream and down stream has also been clearly shown by fish raising farmer in An Giang and Cantho. The grade of good and medium was in reverse order between An Giang and Cantho. The reason might be water of upper stream from Cambodia is still clean because fish culture is mainly practiced in Cuu Long delta. Waste water was discharge directly to water source by about 70% in An Giang and 80% in Cantho. Fish raising farmers having settling ponds are quite few (5-8%) and about 15-25% used waste water for rice cultivation. 3 Table 1. General socio-economics aspects of rice and fish farming households Cantho An Giang Items Fish culture Rice culture Fish culture Rice culture Age of household head 43 49 47 47 Level of education 7/12 5.5/12 5.7/12 5.8/12 Years of experience 3.6 20 9.4 20 No. persons/family 5.3 5.5 5.2 4.8 No. labourers/family 3.4 3.6 3.7 3.0 Land tenure area (ha) 0.6 1.2 0.58 1.50 House types (%) - Concrete - Brick - Thatch 43 42 15 23 73 4 42 39 19 48 44 8 Irrigation water source Canal and/or river Canal and/or river Canal and/or river Canal and/or river Water quality (%) - Good - Medium - Bad 30 52 18 55 22 23 51 25 24 46 39 15 Wastewater discharge - River or canal - Paddy - Settling pond 80 15 5 100 68 24 8 100 Variation on water quality was a concern for farmers (Table 2). Water quality is good during flooding time (Aug. to Dec) mainly because of large flows of water which dilute and wash away pollutants. Waste from fishpond was the major source causing pollution of rural areas both at An Giang and Can Tho. More than 50 % of people in An Giang used river water for living purposes but more or less this proportion of people in Cantho utilized tubewell water. This figure also represented the severity of water pollution in river and forcing people to use tubewell water. Threats for fish culture might also come from pesticides discharge from paddy. The severity was more in down stream where pesticides were accumulated. Rainy season and just after flooding time also had good water for irrigation but it was only accepted by 30 % of total farmers being interviewed. II. Economic efficiencies in rice and fish culture Survey data demonstrated that fish farming generated much higher benefit than rice about 410 millions dong/ha for fish in comparison with 9 millions/ha for rice. However; total cost for raising 1 hectare of fish was 1,894.6 million dong compared to only 12.1 millions dong for rice (Table 3). There was not much difference between Cantho and An Giang province regarding economic efficiency in agriculture production for rice and fish farming. Most of farmers raising fish had to get loans either from banks or neighbours but percentages of rice farmers borrowing money were below 50% because total investment for rice production is much less than for fish culture (Table 4). 4 Table 2: Quality of water for irrigation and for living & drinking in rural areas Items An Giang (%) Can Tho (%) Water source for living & drinking River 57 17 Tube well 13 57 Public water supply 30 26 Water quality for living purpose Good 46 80 Medium 18 13 Bad 36 7 Reason for bad quality of water Waste from fishpond 91 37 Pesticides from paddy 9 15 Others 0 48 Time having good water quality for irrigation Flooding 62 58 Winter-Spring 7 13 All year round 7 5 Rainy season 28 17 Table 3: Comparison of economic efficiencies in rice and fish farming in Cantho Items Fish farming (X Mil. dong) Rice farming (X Mil. dong) T value Total cost/ha 1894.6 12.1 6.2** Yield/ha 170 6.9 6.2** Total income/ha 2305 21.2 6.4** Profit/ha 410.2 9.1 4.9** Income/family/year 178 24.8 5.4** Table 4: Credit sources for agricultural production. Items Cantho An Giang Rice farmers borrowing money (%) 35 44 Farmer raising fish borrowing money (%) 89 95 Sources of credit Bank 32 63 Private 3 4 Company (non-currency) 65 33 Interest rate/year (%) Bank 14 14.6 Private 43 48 Company 26 27.6 5 Percentages of farmers in An Giang province accessing credit from banks were higher than that in Cantho (Table 4). This might be because infrastructure of An Giang was better than in Cantho or roads networks in An Giang favoured transportation. However, late payment agreement between farmers and companies or traders were more common in Cantho than in An Giang. The reason might be due to trading and factories in Cantho had long been developed in Cantho. Generally, interest rate/month was about 1% for bank, approximately 2% for agreement of late payment and up to 4% for individual or private sources. III. Farmer practices in rice and fish farming III.1 Rice production Use of agricultural chemicals is unavoidable in rice production to control insects and pests but misuse of these will contaminate soil, water and the food chain. Survey data in Table 5 showed that brown plant hopper and blast were the most common threat to rice production in the Cuu Long Delta. 84% of farmers in Cantho and 77% in An Giang used insecticides to control brown plant hopper. Chemicals for protecting rice against other insects (leaf folder, stemborer, thrips, bugs, etc.) were second in importance and they had been applied only by 16% of farmers in Cantho and 23% of farmers in An Giang province. More than 50% of farmers in Cantho and An Giang bought fungicides to control rice blast; other fungal diseases had also been controlled but in less than 50% of cases. Survey data showed that 90% of farmers in Cantho applied correct dosages of agricultural chemicals but this figure in An Giang was lower than in Cantho (only 77%). Timing for chemical applications was varied depending on occurrences or observations on outbreak of pests. Farmers in An Giang province had a tendency to spray chemicals based on observation (80%) but farmers in Cantho preferred to use chemicals periodically (52%). Regarding environmental protection, farmers collected used chemical bottles and sold plastic wastes for recycling (70% of case in An Giang) or buried them. However, burning or discarding them were practiced by 60% of cases in Cantho and 16% in An Giang . These practices should be avoided to reduce air, soil and water pollution (Table 5). Technology dissemination and transfer to farmers are very necessary to improve their knowledge for better management of rice and fish farming. This routine work is done regularly every year. Nearly 70% of farmers in Cantho had been trained in agricultural production but in An Giang province the proportion was below 50%. Besides this farmers could also access new technologies through radio or television (Table 6). Rice varieties is one of the decisive factors to increase yield. All of farmers in Cantho and An Giang knew ways to get new varieties of rice (through research institution, centre, state farm and/or exchange with other farmers). The most severe threat to the environment is burning of rice straw in triple rice system even though farmers had been taught many alternative methods to mitigate this effect (straw mushroom cultivation, composting, feeding cattle). Shortage of labour, time, difficulty in transportation, high cost of petrol, unavailability of space for treating rice straw are reasons for non-adoption of sustainable straw management (Table 6) 6 Table 5. Uses of chemicals in rice production Items Cantho (%) An Giang (%) Insecticides BPH control (Bassa, Applaud, Actara, Apolo) 84 77 Others (Karate, Furadan, Regent, Padan) 16 23 Fungicides Blast (Beam, Flash, Fuan, Trizole, Kasai, Repsai) 60 52 Others (Tilt, Anvil) 40 48 Dosage Recommendation 90 77 Higher than recommendation 8 26 Lower than recommendation 2 7 Timing Occurrence 48 80 Fixed schedule 52 20 Container treatment Burning 60 16 Buried 20 5 Throwing 15 9 Recycling (selling) 5 70 Table 6: Accessibility to information on rice production techniques (%). Items Cantho An Giang Information Through radio, TV 90 93 Not watching TV or listening radio 10 7 Attending training course 70 47 Not being trained 30 53 Rice varieties Self multiplication 33 47 Buying from institution, centre, state farm 32 21 Exchange between farmers 35 32 Use of agricultural by products Burning 60 92 Selling for mushroom culture 29 5 Feeding cattle 11 3 III.2. Fish production Catfish has been raised in An Giang province for a long time but culture areas were limited by numbers of fingerlings that could be harvested naturally (at Chau Doc district – An Giang province) during flooding time normally at August to October when they travel down to Cuu Long delta from Tonle Sap catchment of Cambodia. Catfish industry has been developed very quickly only after the year 2000 when Can Tho 7 University developed techniques to produce fingerlings of catfish artificially and international market for export was established. Catfish industry is quite new to farmers which is why support by government in dissemination of technology is really important through broadcasting, printed materials or even sending technicians to field sites. Data in Table 7 showed that this support to fish raising farmers was considerable. An Giang province has the largest catfish industry of the Cuu Long delta both in area and total production. Fish raising farmers in An Giang paid more attention to information or techniques than those in Can Tho (82% in An Giang comparison to 75% in Can Tho). They also received support from technicians more than in Cantho (Table 7). Fish culture requires substantial labour for routine work such as feeding, pumping water and even guarding at night time as a result numbers hired labourers in An Giang was much higher than in Can Tho. Table 7: General information on fish culture Items Can Tho An Giang Information accessibility (%) 75 82 Technical support (%) 42 60 Hired labours (%) 38 72 Type of fish culture (%) Catfish (%) 86 90 Others 14 10 Average time for fish raising (month) From seed – fingerling 2.1 2.0 From fingerling – selling size 6.2 5.8 Depth of fishpond (m) Fingerling 1.7 1.5 Selling size 3.3 3.5 Density of fish /m 2 33 35 Conversion factor (feed/meat) 1.5 1.6 There was not much difference in time of raising fish or depth of fishpond as well as density of fish per square metre between the two locations. However, density was quite varied among farmers from the lowest of 12 fish to the highest of 60 fish/m 2 . There was a high positive correlation between fishpond size or area and total fish harvesting (r = +0.842) but negative correlation between area and depth of fishpond (r = -0.365). Farmers having larger areas can raise high numbers of fish so they can harvest more than those who have smaller area. On the other hand, farmers holding small areas wanted to increase their production by increasing fish density/m 2 . This had been proved by negative correlation between area and fish density (r = -0.520). Farmers in Cantho preferred to use pellets for raising catfish while those in An Giang mainly prepared feed by themselves due to availability of discard sea fish from the adjacent coastal Kien Giang province. As a result, conversion factor from feed to meat in An Giang was higher than in Cantho and this figure was more or less the same in Dong Thap province which had a conversion of 1.47 (Pham quoc Nguyen 2008). Cantho and Dong Thap had many feed companies which were close to fishpond sites. In preparation of ball feed, most farmers had to add additives either in the form of concentrated premix 8 comprising vitamins, enzymes and minerals besides using some traditional inputs like rice bran, soybean and broken rice. Most farmers gave feed two times per day (Table 8) normally at early morning and before sunset. Others fed catfish once or four times per day but these practices were not common in the Cuu Long delta. Regarding the quantity of feed given per time, all of farmers at two sites said they supplied just sufficient food for fish about 1/10 of fish weight because surplus feed can ruin water quality. The most common practice by farmer to detect any change in water quality was done by observation of water colour. Table 8: Feed quality and feeding times/day Items Can Tho An Giang Type of feed (%) Pellet (from industry) 55 27 Ball (self produce) 37 58 Mixed (pellet+ ball) 8 15 Use of additive 88 66 Types of additive Vitamin 64 69 Enzyme 57 74 Minerals 23 36 Times of feeding/day Once 23 12 Twice 43 78 Three time 27 10 Four time 7 0 Observation Detection of surplus feed 33 40 Changing feed 32 10 Catfish raising ponds experience high fish mortality. Survey data indicated that losses for raising seed was about 50% and that of commercial fish was a little more than 20% (Table 9). Diseases spreading by polluted water and fish sources were among causes for high mortality. Different diseases on catfish were reported (Table 10) mainly caused by parasites and virus. Farmers blamed fish sources for fish death but the main reason for this was caused by carrying high numbers of fingerlings in close bag or container. During transportation they were hurt by scratching because catfishes have very sharp spines on their heads. Another reason is caused by changing environment when fishes were put in to new ponds for raising. Those two causes collectively cause high mortality when re- stocking ponds. According to farmers, environment also affected fish heath but this was not so important in comparison to the other two cases cited above. Interviewed on planning for catfish production in the near future, most farmers in An Giang province (85%) and Cantho (68%) said they do not have any intention to invest more on catfish production. This revealed that farmers were not so happy with catfish production because there are a lot of uncertainties in price of selling fish, inputs (feeding, chemicals for water treatment and diseases controls). Under market oriented economics system, low level educated farmers should be assisted in production in order to increase 9 their profits. Only 25% of farmers in Cantho and 11% of those in An Giang planned to increase their production. Again this data confirms that catfish production could not attract more farmers to invest on this job. Planning for set up settling ponds was also not being considered by most of the farmers interviewed. Quite a few farmers were reluctant to answer during interview but really they have never think about it. Table 9: Percentage of mortality and causes Items Cantho An Giang Mortality rate Fingerling 47 52 Commercial fish 22 24 Causes of loss Diseases 50 32 Fish source 37 57 Environment 13 11 Current fish status Having disease 68 72 Stable 27 24 Not know 5 5 Planning for future production No plan 68 85 Increase production 25 11 Make settling pond 7 4 Concerning on the use of bio-products and chemicals for water treatment in catfish culture, nearly 50% of farmers at both sites had used Vikong, BKC, Bioca, Yulai, Aquapure, Prawbac and some other products (Table 10). They also used antibiotics to control mainly bacterial diseases in the digestive tract of catfish. Some common antibiotics like Amoxycilline, Cotrim, Penicilline, Kanamycine, Oxamet and Tetracylline had been used mainly by mixing into feeds in An Giang (96%) or putting directly into water (40% of farmers in Cantho following this method). According to farmers, these antibiotics were very effective to control catfish diseases. Fortunately, almost all of farmer used antibiotics at recommended dosage otherwise these chemicals will cause problems to the environment and possibly in international markets also. For sanitary purposes and control of algae in fishpond, 93% of farmers in Cantho and about 66% in An Giang province applied copper sulphate, BKC, Vikong, Chlorine, juka and even salt or lime (Table 10). Among these BKC and chlorine were the most common chemicals which had been used both in An Giang and Cantho. Water management is very important in catfish culture for new and current used ponds. All farmers normally spreaded lime or salt along the sides and bottom of pond after making a new one or after draining out all water after harvesting fish from ponds. Dosages of lime and salt varied from 300-400 kg/ ha. Pond will then be kept dried from 3-5 days before pumping water in for a new crop. More than 95% of farmers changed and/or added water to fish ponds regularly (about 1/3 volume of pond) and there was about 50% farmers at both sites who practiced bottom of fishpond cleaning by pumping out sludge while raising catfish to secure good water quality. However, all of farmers had 10 to pump sludge out of their pond after harvesting fish (Table 11). The practice of discharging waste directly to water source could caused water pollution. Most of farmers had handheld a pH meter to monitor water quality. Other ways to detect water quality were by observation of water colour or smelling the odour of water. If oxygen is deficient most of fishes will come to surface of water early morning; farmers will then know oxygen in fishpond is sufficient or not. Table 10: Chemicals used for water treatment. Items Cantho An Giang Bio-products (%) 48 43 Antibiotics (%) 72 54 Mixing to feed 60 96 Mixing with fishpond water 40 4 Water treatment 97 100 BKC 21 28 Vikong 43 5 Copper sulfate 7 8 Chlorine 21 10 Others 8 49 Efficacy (2+3) 100 100 Table 11: Water management in catfish culture. Items Cantho An Giang Renewed fishpond (%) 100 100 Lime (kg/ha) 425 350 Salt (kg/ha) 325 300 Dried bottom of pond (%) 100 100 Days of drying 3.5 4 Filled up and/or changed water periodically (%) 98 100 Volume of added or changed water 1/3 1/3 Water quality monitoring pH 95 90 Colour or odour 8 12 NH 3 and Oxygen 62 65 Sludge discharged During raising time (%) 50 50 After harvesting (%) 60 75 Survey data on diseases of catfish are presented in Table 12. The most severe and widespread disease to catfish is caused by bacteria (about 90%) causing death of catfish. The most common symptoms of bacterial disease called haemorrhage producing red appearance on mouth, fins and tail. Other diseases are called swelling head and slimy loss but they are of minor importance. [...]... City and in Chau Phu and Phu Tan districts of An Giang province According to data collected at the Preventive Medicine Center in O Mon and Thot Not districts during 2006 and 2007 dengue was increased This disease outbreak by the end of 2008 mainly in the south Vietnam; the situation was most severed in An Giang and Dong Thap provinces (Department of Preventive Medicine – MOH Vietnam, 2008) Data in Table... raising farms are distributed on high elevated land (no flooding) where cattle could be raised easily There are quite a few vermicompost farms in Cantho The situation is different in An Giang province because of flooding although numbers of cattle in An Giang are among the highest in this delta Data on surveys in Cantho (Table 17) showed that number of farmers used organic manures for rice production... not common mainly because of low economic efficiency though they were trained on organic farming However, numbers of farmers in Binh Thuy and Phong Dien under VAC system used manures were higher because in these areas they grow fruit trees and vegetables which are higher value than paddy 13 Table 16: Organic manure production and use for farming at Cantho city Items VAC system Paddy Binh Thuy Phong Dien... OMon Thot Not Vermiculture farm 5 1 2 1 Home made manure - Compost 14 11 5 8 - Org manure 2 3 1 - Green manure 8 6 Organic manure application 42 38 12 27 Knowledge on organic 65 72 28 16 farming Training participation (%) 7 4 15 18 VI Reports on diseases caused by water pollution: Investigations on diseases attributable to water pollution have also been completed in OMon and Thot Not districts of Cantho. .. training on recycling of agricultural byproducts to make organic manures and to reducing greenhouse gas emissions Through training, farmers will understand the role of organic matter in sustainable agriculture production This goal is realistic because prices of fertilisers and pesticides are quite high nowadays Another opportunity for encouraging farmers to raise earthworm and produce vermicompost in. .. indicated that diahorrea in 2007 was higher than in 2006 Dengue, diahorrea and dysentery in Phu Tan were much higher than those in Chau Phu and they had a tendency to increase These might be related to the closed dike system at Phu Tan district where water in canals could not be drained As presented in Table 2, most of people in An Giang province (57%) are still use river or canal waters as the main... survey in Cantho City: A broad survey of VAC practices was carried out in the suburb of Cantho city at 2 districts, namely Binh Thuy and Phong Dien Orchards or fruit tree plantations were mainly kept on elevated soil adjacent to ditches or ponds Longan, milky fruit, durian, rambutan or oranges/lime are the most common fruit trees in these areas Duck has been raised in the largest numbers among others... resulting in high pollution in these areas up to the limit that any natural fishes could survive and navigation is often obstructed due to sludge filling up rivers and/ or canals bases The conflict between Clarias fish raising farmers and people living in these areas 11 are quite common so it is quite difficult to convince them to cooperate Although local authorities had issued regulations banning direct... used for feeding high quality fishes or prawn Farmers using VAC can make use of ditches in between ridges for aquaculture V Surveys on production and consumption of vermi-compost Vermicompost is directly linked to earthworm raising Animal manures are very essential for bedding and feeding earthworms Hence most worm raising farms are located next to dairy farms or swine pens In the Cuu Long delta, earthworm... pay more labour for controlling weeds Although farmers know some benefits of organic manure for cultivation of vegetable and fruit trees but self-made compost or manure have not commonly used due to the following reasons: - Time consuming; - No visual effect of manure application; - Shortage of labour in agriculture sector; - High cost for transportation and application; - Organic products sold at . etc.) were second in importance and they had been applied only by 16% of farmers in Cantho and 23% of farmers in An Giang province. More than 50% of farmers in Cantho and An Giang bought fungicides. better than in Cantho or roads networks in An Giang favoured transportation. However, late payment agreement between farmers and companies or traders were more common in Cantho than in An Giang. . stream and down stream has also been clearly shown by fish raising farmer in An Giang and Cantho. The grade of good and medium was in reverse order between An Giang and Cantho. The reason might