CN100377640C - A method for improving the ecological environment of seawater ponds - Google Patents

Abstract

The invention discloses a method for improving the ecological environment of a seawater pond, which is characterized in that a culture raft frame is set in the seawater pond, and a net for cultivating laver is all seedlings, and the ratio of the laver cultivation area to the entire water surface area is kept at 1 : 10～30, the application of the present invention can greatly reduce the nutrient element indicators such as nitrogen and phosphorus in seawater ponds, and is conducive to the zero discharge or negative discharge of nutrients such as nitrogen and phosphorus in seawater ponds, so that the planktonic in the water body Animals and benthic algae or planktonic algae are dynamically balanced, increasing the dissolved oxygen in the water body, reducing carbon dioxide, appropriately increasing the pH value of the water body, and improving the bottom quality in seawater ponds; the invention can reduce the number of water changes in seawater ponds, Increasing the growth time of economic animals can also save manpower and material resources for changing water, as well as energy and water consumption; the invention can also increase the additional income of laver at the same time.

Description

A method for improving the ecological environment of seawater ponds

technical field

The invention relates to a method for improving the ecological environment of puhai ponds.

Background technique

Most of the existing seawater ponds are mainly used for cultivating economic animals, such as shellfish such as razor clams and clams, as well as fish, shrimp and crabs. During the breeding process, the residual bait, animal corpses and excrement and excrement will increase the concentration of nutrients in the water, resulting in a decrease in dissolved oxygen in the water and an increase in the concentration of ammonia nitrogen, thereby destroying the ecological environment of the breeding water, especially the concentration of ammonia nitrogen. If it is too high, it will have a greater toxic effect on common economic animals. In addition, one or more types of benthic algae or planktonic algae often exist in the aquaculture water body, and when conditions are suitable, they will grow rapidly and their density will continue to increase, which will also have a greater impact on the aquaculture of economic animals. With the intensification of human economic activities and the rapid improvement of living standards, a large amount of industrial and agricultural wastewater and domestic sewage flow into rivers and lakes, and finally this is discharged to the offshore, coupled with large-scale marine development activities, the pollution of the breeding environment itself has led to The high eutrophication of aquaculture waters has caused the overload of the self-purification ability of nutrients in the coastal water ecosystem, and the pollution of the marine environment has become increasingly serious. The main feature of eutrophic water quality is that the concentration of nutrients such as nitrogen and phosphorus in the water body is too high. When the conditions are right, it is easy to cause a large number of phytoplankton algae in the water body. The time is also longer. At present, the general measures taken to improve the ecological environment of seawater ponds are to change the water one to three times a month to reduce the impact of benthic algae or planktonic algae and ensure good water quality in seawater ponds. But this is time-consuming and labor-intensive, and consumes a lot of manpower and material resources. If the water is changed too little or not in time (this is a phenomenon that often occurs in small tides), it is easy to cause a large number of benthic algae or planktonic algae to form water blooms or red tides, commonly known as pond turning, which affects the normal growth of economic animals; and If the water is changed too frequently, it will lead to increased costs. Another problem is that changing water in large-scale sea ponds often causes the discharged water to be reintroduced into aquaculture water, thereby reducing the efficiency of water exchange. The long-term exposure of seawater ponds will directly affect the survival rate of economic animals. Another method for improving the ecological environment of seawater ponds is to use water quality improvers or substrate improvers to inhibit the growth of phytoplankton, as disclosed in the Chinese invention patent No. 03126702.5 issued on October 20, 2004. The improver for the ecological environment of the bottom of the breeding pond and its use method can better improve the ecological environment of the pond culture, but the use of this improver can only play a short-term effect once every 10 to 20 days. Apply once, the cost is relatively high.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for improving the ecological environment of seawater ponds, which can maintain the dynamic balance of zooplankton and benthic algae or planktonic algae in the water body for a long period of time. , not only can reduce the pressure on water quality eutrophication, improve the ecological environment of seawater ponds, but also produce good additional economic benefits.

The invention discloses a method for improving the ecological environment of seawater ponds, which includes setting a culture raft frame in the seawater pond, and a whole seedling net for cultivating laver, and keeping the ratio of the laver cultivation area to the entire water surface area at 1:10-30.

The laver cultivation area is preferably set in the ring ditch of the seawater pond.

The direction of the culture raft frame is preferably set to be perpendicular to the wind direction.

In the process of cultivating laver, harvest 7-15% of laver each time, and increase the corresponding number of new whole seedling nets to ensure the amount of laver cultivation.

In the process of laver cultivation, the whole seedling net should be shaken in time to remove the sediment on the surface of the fronds.

In the laver culture process, according to the growth of the seedling net, by adjusting the length of the sling on the raft, put the net into the water or dry the seedling net out of the drying net to ensure that the laver has a normal and suitable growth rate. Regulate the population of benthic microalgae or planktonic microalgae through the growth of laver, combined with water quality detection and analysis, measure the population dynamics of laver, economic animals and phytoplankton, the concentration of N and P in the water body, and measure the concentration of the water body The degree of transparency and the intensity of light have an impact on the population quantity and quality of all organisms in the water body. The growth of benthic algae or planktonic algae and Porphyra thallus is synchronous. The concentration of N and P is high, the transparency is high, and the light is strong, and the population will increase. At this time, the growth and quantity of Porphyra should be appropriately increased; N, P If the concentration of laver is low, the transparency is small, and the light is weak, the growth and quantity of laver should be appropriately reduced, and the method of adjusting the water layer should be combined to ensure the normal growth of laver fronds.

It takes 2 to 3 hours to dry out the drying net each time.

The whole seedling net can be a sea area seedling raising net or a cold storage net.

The application of the present invention can greatly reduce the indicators of nutrients such as nitrogen and phosphorus in seawater ponds, and is beneficial to the zero discharge or negative discharge of nutrients such as nitrogen and phosphorus in seawater ponds, so that zooplankton and benthic algae in the water body Or the dynamic balance of planktonic algae can increase the dissolved amount of oxygen in the water, reduce carbon dioxide, appropriately increase the pH value of the water body, and improve the substrate in the seawater pond; the laver fronds affect the nutrient salt of the planktonic algae by competing for nutrients. Absorption; laver fronds cover seawater ponds, which affects the absorption of light by planktonic algae, weakens photosynthesis of planktonic algae, and causes slow growth of planktonic algae; the present invention can reduce the number of water changes in seawater ponds and increase the growth rate of economic animals time; it can also save manpower and material resources for water change and energy and water consumption; setting the seaweed cultivation area in the ring ditch of the seawater pond is conducive to operation and management; It is beneficial to the exchange of water in the laver breeding area; timely oscillation of the whole seedling net is beneficial to remove the sediment on the surface of the fronds; timely putting the net into the water or drying the seedling net out of the drying net can ensure the normal and suitable growth of laver Speed; in the cultivation of seaweed in seawater ponds, a large number of biological populations appear on the surface of seaweed fronds, resulting in some floating into seawater ponds to cultivate a technical system for the ecological regulation of seaweed whole seedling nets, ensuring that the time-consuming and labor-intensive situation is minimized Under this condition, the growth of laver is completely normal, reducing the eutrophication pressure on the environment. The invention can also increase the additional income of laver at the same time.

Description of drawings

Fig. 1 is the cross-sectional structure schematic diagram of the seawater pond that the method of the present invention applies.

In the figure, 1 is a seawater pond, and 2 is a ring ditch.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Embodiment one: From November 15th to December 12th, 2003, it was carried out in the seawater pond of Nantiantang Breeding and Development Company, Xiangshan County, Zhejiang Province. The depth is 0.9 meters, and the depth of the ring ditch is 1.8 meters. The laver seedling net uses the sea area seedling net and is directly hung on the seawater pond. 2 units are arranged on the ring ditch in the north and the south, and they are dried for 2 to 3 hours on November 19, November 22, November 27, December 2, and December 7.

The water quality factors such as dissolved oxygen, pH value and oxidation-reduction potential of the water body were measured with the YSI6600 water quality measuring instrument. After laver cultivation in the ponds, compared with the seaweed ponds in the comparison, they all increased by 10-30%. Inorganic nitrogen decreased from the initial 956.94 μg/L to 108 μg/L, the level of total inorganic phosphorus decreased from 19.96 μg/L to 2 μg/L, and the concentrations of ammonia nitrogen, phosphate, nitroso nitrogen and nitro nitrogen were compared with those of The initial level has dropped by 84%, 89%, 80% and 95%, and the nitrogen and phosphorus indicators of the water quality have reached the first-class seawater standard.

Laver was harvested on November 22, December 2 and December 12, and 207, 182, and 226kg of dehydrated fresh vegetables were harvested. Calculated at 1 yuan/kg, the output value increased by 615 yuan, and the net income was 385 yuan after removing the cost. Yuan. Red tides appeared in other ponds due to Xiaoyangchun, resulting in a loss of 50,000 to 120,000 yuan for 70% of the ponds. In the ponds where laver is cultivated, there is basically no death of economic animals.

Embodiment two: carried out in the seawater pond of Hepu, Xiangshan County, Zhejiang Province from March 12 to April 17, 2004. The pond is 135 meters * 40 meters, and runs north-south. The depth of the beach surface of the seawater pond is 0.8 meters, and the depth of the ring ditch is 1.8 meters. Laver seedling nets are provided by Ningbo University’s cold storage nets, which are directly hung in seawater ponds. The size of each laver seedling net is 2.4m x 2.4m, and 8 pieces form 1 set, and 2 sets are arranged on the north and south ring ditches respectively. , respectively on March 18, March 22, March 27, April 2, and April 7 for 2 to 3 hours.

The dissolved oxygen, pH value, oxidation-reduction potential and other water quality factors of the water body were measured with the YSI6600 water quality analyzer. After the seaweed cultivation in the ponds, compared with the seawater ponds in the control, they all increased by 10-30%. The analyzer determined that the total inorganic nitrogen in the pond dropped from the initial 1174.4μg/L to 171μg/L, the level of total inorganic phosphorus dropped from 23.55μg/L to 2.4μg/L, ammonia nitrogen, phosphate, nitroso nitrogen, nitrate The concentrations of basal nitrogen were decreased from the starting level. The nitrogen and phosphorus indicators of the water quality can reach the first-class seawater standard. Laver was harvested on March 27, April 9 and April 17, and 179, 202, and 196kg of dehydrated fresh vegetables were harvested. Calculated at 1 yuan/kg, the output value increased by 577 yuan. 179, 202, and 196kg of dehydrated fresh vegetables, calculated at 1 yuan/kg, increased the output value of 577 yuan, and the net income was 350 yuan after removing the cost.

Embodiment three: from November 2 to December 16, 2004, it was carried out in the seawater pond of Nantiantang Breeding and Development Company in Xiangshan County, Zhejiang Province. The pond was 67 meters * 40 meters, and the direction was north-south. The depth of the beach surface of the seawater pond is 0.9 meters, and the depth of the ring ditch is 1.8 meters. Laver seedling nets are provided by Xiangshan Longxin Laver Co., Ltd., which are taken from the sea area. After drying in the shade, they are directly hung in seawater ponds. The size of each laver seedling net is 2.4m x 2.4m, and 6 pieces form a set, respectively in the north and south circles. 2 units were arranged on each ditch, and they were dried for 2 hours on November 6, November 10, November 14, November 17, November 24, and November 30. On November 6, Laver was harvested on November 14, November 23, and December 6, and 238, 202, 175, and 211kg of dehydrated fresh vegetables were harvested, totaling 826kg of dehydrated fresh vegetables. Calculated at 0.9 yuan/kg, the output value increased by 730 yuan , excluding the cost, the net income is 480 yuan. The dissolved oxygen, pH value, oxidation-reduction potential and other water quality factors of the water body were measured with the YSI6600 water quality measuring instrument, and compared with the control seawater pond, they all increased by 10-35%. Due to Xiaoyangchun, red tides appeared in other ponds, which caused 70% loss of ponds, and the loss reached 50,000 to 120,000 yuan. However, there is basically no obvious economic animal death in the ponds where laver is cultivated.

It was observed that after laver was mixed in the pond, the activities of shrimp and fish were more frequent in this area, and there were more fluctuations in the water body, which indicated that the cultivation of laver in the pond improved and enriched the diversity of the living environment of economic animals , economic animals that are conducive to farming are relatively concentrated in the area where laver is cultivated.

Claims (8)

1. a method of improving ecological environment of enclosed seawater pond is characterized in that it is that culture raft frame is set in enclosed seawater pond, the whole seedling net of cultivation of porphyra, and the area of laver culture and the ratio of whole water surface area remain on 1: 10～30.

2. a kind of method of improving ecological environment of enclosed seawater pond as claimed in claim 1 is characterized in that described laver culture zone is arranged in the circular groove of enclosed seawater pond.

3. a kind of method of improving ecological environment of enclosed seawater pond as claimed in claim 1 is characterized in that described culture raft frame moves towards to be arranged to vertical with wind direction.

4. a kind of method of improving ecological environment of enclosed seawater pond as claimed in claim 1 is characterized in that in cultivating the laver process, 7～15% the laver of at every turn gathering, and guarantee the laver culture amount by the new whole seedling net that increases respective numbers.

5. a kind of method of improving ecological environment of enclosed seawater pond as claimed in claim 1 is characterized in that the whole seedling net that will in time vibrate in the laver culture process, remove the lip-deep sediments of thallus.

6. a kind of method of improving ecological environment of enclosed seawater pond as claimed in claim 1, it is characterized in that will be according to the growing state of seedling net in the laver culture process, by regulating the length of lifting rope on the culture raft frame, put the net entry or make the seedling net do the solarization net, guarantee the growth rate that laver has normally, suits.

7. a kind of method of improving ecological environment of enclosed seawater pond as claimed in claim 6 is characterized in that do the time of shining net is 2～3 hours at every turn.

8. a kind of method of improving ecological environment of enclosed seawater pond as claimed in claim 1 is characterized in that described whole seedling net is breeding in sea net or cold net.

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