The technology of polyculture between the indigo and prawn is the oyster shellfish of the family Polygonaceae. It lives in coastal mudflats and is a common economic shell in the coastal areas of China. The existing shrimp culture area along the coast of Binzhou City, Shandong Province, is 170,000 mu. Affected by shrimp viral diseases, the shrimp industry has not yet reached the bottom, resulting in great waste of land and water resources. In order to give full play to its advantages in resources, actively adjust the structure of the fishery industry, and vigorously develop the barley breeding industry, the author conducted a polyculture test on the barley and shrimp in a pond of shrimp cultivation with an area of ​​80 mu, and achieved remarkable economic, social, and ecological benefits. . The polytechnics of the barley and shrimp are summarized as follows:
I. Pond conditions
The pond is a shrimp culture pond with an area of ​​80 mu and is rectangular. There are ring grooves around the bottom of the pool. When the water level is full, the ring groove is 1.3m deep, the middle beach surface is 0.9m deep, and the ratio of the ring ditch to the beach area is 1:1.2. There is an independent intake and drainage system; the sediment of the pond is muddy and sandy; the use period of the pond has reached 12 years, and the bottom of the pond is ploughed every 3 years.
Second, the bottom flat and disinfection
On April 5th, drain the pool water, remove stones, shells, and rubble, and level the bottom of the pool with oysters. Then fill the water with 10cm. Sprinkle with 150kg/mu of quicklime and pour the whole pool of water to completely destroy the pool. Bacteria, viruses, protozoa, fish and other pests.
Three, fertilizer
5 days after the pond was disinfected, the medicinal properties of the drug disappeared. The water was filtered with a 60-mesh sieve to a depth of 50cm on the beach, and urea was applied at 1kg/mu and superphosphate 0.5kg/mu to reproduce phytoplankton.
Fourth, seed stocking
Barley seedlings were taken from the salt field and had an average shell length of 17.2 mm and an average body weight of 1.62 g. On April 11th, the water temperature reached 14.3°C, and 3933 kg of young seedlings were uniformly spread on the surface of ponds. The average seeding density was 90.2 kg/mu.
China's prawn seedlings were taken from the Wupi County shrimp nursery. On May 11th, the water temperature reached 18.2°C, and 350,000 tails with an average body length of 0.9cm were placed in the pond. The average seedling density was 4375 tails/mu.
V. Daily management
1. Feed feeding. Shrimp aquaculture is only fed with high-quality artificial compound feed, and it is forbidden to feed fresh live bait such as Artemia or blue pelicans. The method of feeding compound feed is spreading uniformly around the pond at a depth of 1.0m, and the daily feeding amount is 0.7%--1.5% of the prawn weight, but it is mainly based on the shrimp's stomach fullness rate, weather and water temperature. set. After feeding for 2 hours, check the shrimp stomach fullness rate of 50% for moderate feeding. Rainy days, sweltering days, windy days, when the water temperature is lower than 15°C or higher than 32°C, it will be fed less or not.
2. Water quality management. The color of the aquaculture pond should be yellow-green. The transparency of the water body should be kept between 30cm and 40cm, the specific gravity should not exceed 1.025, and the pH should be 7.8--8.6. O≥5mg/L, NH3-N
3. Predator control. When entering the water, make sure that the water inlet network is not damaged and prevent fish, shrimps, crabs, and other harmful organisms from entering the pool. When there is crab in the pool, it will be removed with strong light at night; if there is any water cloud in the pond, remove it out of the pool in time; when there are sea birds on the pond, use whistling, knocking and other methods to drive away.
Six, breeding results
1. Yield. After 7 months of cultivation, the barley has a total harvest of 10983.2 kg, which is equivalent to 289.55 kg per mu. After 5 months of culture, the prawns harvested 508.8 kg, which is equal to 6.36 kg per mu.
2. Growth rate and survival rate. The average length of the shells of the green barley seedlings was 17.2 mm, and the average individual body weight was 1.62 g. The average shell length was 24.8 mm, an increase of 7.6 mm, and the average individual weight was 5.20 g, an increase of 3.58 g. Calculated in terms of quantity and harvest amount, the survival rate of green barley breeding reached 87.0%; the average length of shrimp prawns was 0.9cm, the average body length after breeding for 5 months was 11.6cm, an increase of 10.7cm, and the survival rate of shrimp aquaculture was only 7.75%.
3. Benefit Analysis. The input-output ratio of this experiment is 1:2.2, and the economic benefits are significant. This experiment is based on the cultivation of barley, which is a filter-feeding organism that ingests phytoplankton, organic debris, bacteria, etc., and plays a role in purifying water quality. Therefore, the project has significant ecological benefits.
VII. Analysis and Discussion
1. Many years of shrimp rearing ponds are rich in organic matter, which is conducive to the breeding of benthic diatoms. Qingyin camp buried life, is conducive to increase the permeability of the sediment, thereby accelerating the oxidative decomposition of organic matter in the bottom mud, improve the bottom environment.
2. The shrimp feed is artificial compound feed, and the residual bait can be used as organic fertilizer to make the phytoplankton reproduce; the barley mainly ingest phytoplankton, organic debris, bacteria, etc., and can purify the water quality. Therefore, the polyculture of shrimp and shrimp is a kind of It is conducive to improving the ecological environment of farming methods.
3. In this experiment, the survival rate of green barley reached 87.0%, which was mainly due to the fact that some small-sized seedlings were immersed in shallow sand and were eaten by shrimp. The survival rate of shrimp was low, mainly due to viral diseases. It is recommended that shrimp farming ponds should be first cultivated for two years of green barnyardgrass, and then a one-year breeding mode for mixed barley and prawns should be carried out.
I. Pond conditions
The pond is a shrimp culture pond with an area of ​​80 mu and is rectangular. There are ring grooves around the bottom of the pool. When the water level is full, the ring groove is 1.3m deep, the middle beach surface is 0.9m deep, and the ratio of the ring ditch to the beach area is 1:1.2. There is an independent intake and drainage system; the sediment of the pond is muddy and sandy; the use period of the pond has reached 12 years, and the bottom of the pond is ploughed every 3 years.
Second, the bottom flat and disinfection
On April 5th, drain the pool water, remove stones, shells, and rubble, and level the bottom of the pool with oysters. Then fill the water with 10cm. Sprinkle with 150kg/mu of quicklime and pour the whole pool of water to completely destroy the pool. Bacteria, viruses, protozoa, fish and other pests.
Three, fertilizer
5 days after the pond was disinfected, the medicinal properties of the drug disappeared. The water was filtered with a 60-mesh sieve to a depth of 50cm on the beach, and urea was applied at 1kg/mu and superphosphate 0.5kg/mu to reproduce phytoplankton.
Fourth, seed stocking
Barley seedlings were taken from the salt field and had an average shell length of 17.2 mm and an average body weight of 1.62 g. On April 11th, the water temperature reached 14.3°C, and 3933 kg of young seedlings were uniformly spread on the surface of ponds. The average seeding density was 90.2 kg/mu.
China's prawn seedlings were taken from the Wupi County shrimp nursery. On May 11th, the water temperature reached 18.2°C, and 350,000 tails with an average body length of 0.9cm were placed in the pond. The average seedling density was 4375 tails/mu.
V. Daily management
1. Feed feeding. Shrimp aquaculture is only fed with high-quality artificial compound feed, and it is forbidden to feed fresh live bait such as Artemia or blue pelicans. The method of feeding compound feed is spreading uniformly around the pond at a depth of 1.0m, and the daily feeding amount is 0.7%--1.5% of the prawn weight, but it is mainly based on the shrimp's stomach fullness rate, weather and water temperature. set. After feeding for 2 hours, check the shrimp stomach fullness rate of 50% for moderate feeding. Rainy days, sweltering days, windy days, when the water temperature is lower than 15°C or higher than 32°C, it will be fed less or not.
2. Water quality management. The color of the aquaculture pond should be yellow-green. The transparency of the water body should be kept between 30cm and 40cm, the specific gravity should not exceed 1.025, and the pH should be 7.8--8.6. O≥5mg/L, NH3-N
3. Predator control. When entering the water, make sure that the water inlet network is not damaged and prevent fish, shrimps, crabs, and other harmful organisms from entering the pool. When there is crab in the pool, it will be removed with strong light at night; if there is any water cloud in the pond, remove it out of the pool in time; when there are sea birds on the pond, use whistling, knocking and other methods to drive away.
Six, breeding results
1. Yield. After 7 months of cultivation, the barley has a total harvest of 10983.2 kg, which is equivalent to 289.55 kg per mu. After 5 months of culture, the prawns harvested 508.8 kg, which is equal to 6.36 kg per mu.
2. Growth rate and survival rate. The average length of the shells of the green barley seedlings was 17.2 mm, and the average individual body weight was 1.62 g. The average shell length was 24.8 mm, an increase of 7.6 mm, and the average individual weight was 5.20 g, an increase of 3.58 g. Calculated in terms of quantity and harvest amount, the survival rate of green barley breeding reached 87.0%; the average length of shrimp prawns was 0.9cm, the average body length after breeding for 5 months was 11.6cm, an increase of 10.7cm, and the survival rate of shrimp aquaculture was only 7.75%.
3. Benefit Analysis. The input-output ratio of this experiment is 1:2.2, and the economic benefits are significant. This experiment is based on the cultivation of barley, which is a filter-feeding organism that ingests phytoplankton, organic debris, bacteria, etc., and plays a role in purifying water quality. Therefore, the project has significant ecological benefits.
VII. Analysis and Discussion
1. Many years of shrimp rearing ponds are rich in organic matter, which is conducive to the breeding of benthic diatoms. Qingyin camp buried life, is conducive to increase the permeability of the sediment, thereby accelerating the oxidative decomposition of organic matter in the bottom mud, improve the bottom environment.
2. The shrimp feed is artificial compound feed, and the residual bait can be used as organic fertilizer to make the phytoplankton reproduce; the barley mainly ingest phytoplankton, organic debris, bacteria, etc., and can purify the water quality. Therefore, the polyculture of shrimp and shrimp is a kind of It is conducive to improving the ecological environment of farming methods.
3. In this experiment, the survival rate of green barley reached 87.0%, which was mainly due to the fact that some small-sized seedlings were immersed in shallow sand and were eaten by shrimp. The survival rate of shrimp was low, mainly due to viral diseases. It is recommended that shrimp farming ponds should be first cultivated for two years of green barnyardgrass, and then a one-year breeding mode for mixed barley and prawns should be carried out.