JPH0347810B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for killing algae, such as algae, generated during the cultivation of seaweed. Generally, seaweed cultivation is carried out near river mouths and in the open ocean by setting nets, but in many cases only green seaweed,
Miscellaneous algae such as Ulva are occurring and causing great damage to seaweed, including diseases such as red rot. For this reason, methods such as drying out or treatment with chemicals such as antibiotics and fungicides have traditionally been carried out.
Not only was the work efficiency low, but the required algaecide effect could not be obtained, and problems of chemical damage to the seaweed and workers and marine pollution occurred, posing a practical problem. Therefore, the present inventors previously proposed a method for exterminating algae by immersing seaweed in a low-PH solution containing an organic acid with an algaecide effect.
No. 12601), it was found that pH adjustment during use was troublesome and there were problems in obtaining stable processing efficiency. That is, in order to prevent or exterminate seaweed diseases caused by the growth of various algae, etc. by immersing a seaweed net in an organic acid solution prepared in a tank of a certain shape,
It is desirable to adjust the pH to about 1 to 5, and
Considering on-site work efficiency, a pH of 2 to 3 is most preferable, but each time the seaweed net is soaked, the solution is taken out of the aquarium, and new seawater and chemicals must be added each time, so this supplement is recommended. As a result, the pH of the solution changes from time to time, making it difficult to stabilize the pH of the solution. The present invention was developed in view of the current situation, and has low solubility as an organic acid, and
Treat objects to be treated such as seaweed nets with fumaric acid or a treatment liquid mainly composed of fumaric acid, whose PH value of the saturated solution in seawater is optimal for exhibiting algicidal effects. The purpose of the present invention is to provide an algaecide method that maintains a certain algaecide effect in the treatment liquid regardless of the number of times that objects to be treated, such as nets, are treated, thereby killing algaecides and other algae generated during seaweed cultivation. The gist of this is that fumaric acid is present in a treatment liquid such as seawater stored in a treatment tank in a state in which it is coated with a water-permeable coating means in an amount exceeding the saturation amount, or that the treatment liquid is In the treatment liquid, an amount of fumaric acid that exceeds the saturation amount and an amount of organic acid such that the PH of the treatment liquid becomes 1.5 to 3.5 are co-existed in a state where the treatment liquid is coated with a water-permeable coating means. This method involves immersing objects to be treated, such as fishing nets, that require water to kill algae. Hereinafter, the details of the present invention will be explained. First, as the fumaric acid according to the present invention, fine powder or acicular crystal powder is used directly or in the form of a tablet, and furthermore, as the organic acid to be coexisting with the fumaric acid, malic acid is used. , one or more selected from citric acid, tartaric acid, and succinic acid, inorganic salts or inorganic acids such as ammonium chloride, ammonium nitrate, orthophosphoric acid, and trace components such as minerals and chelating agents. Become. In addition, especially when processing seaweed at its young bud stage,
Processing solutions can also be prepared using fumarates such as sodium fumarate. In this case, the sodium fumarate and the fumaric acid may be mixed for adjustment. Therefore, the fumaric acid or its combination drug, etc. is sealed in a container made of various papers, cloth, or a synthetic resin sheet with water holes, or an outer shell with water holes, and placed in a separate aquarium. The algaecide treatment solution is prepared by immersing the bag in the seawater filled in the container, and at this time, the amount of fumaric acid to be immersed is, for example, 0.5 to 500% of the seawater.
It may be about 10% (w/v), preferably 1 to 5%
(w/v). As is clear from the graph shown in Figure 1, if fumaric acid is added in a range of at least 0.5 to 10% (w/v) to a certain amount of seawater, the treatment solution will be algicidal. This is because it exhibits a preferable PH value of around 2.2, and the value remains at a constant level without being affected much by the amount added within the above range. Therefore, considering work efficiency and economic efficiency, 1~
A range of 5% (w/v) is most desirable. On the other hand, as shown in the graph in the same figure, when other organic acids or inorganic acids are used alone, the PH value of seawater decreases with the amount added, making the treatment solution unstable. Become. Therefore, in the present invention, the treatment liquid is prepared mainly using fumaric acid, but this fumaric acid is used in combination with other organic acids, inorganic acids, inorganic salts, minerals, and further chelating agents. In this case, the fumaric acid is saturated in seawater, and the range of the algicidal effect is significant, that is, the seawater is
The respective organic acids, inorganic acids, or inorganic salts may be added within the pH range of 1.5 to 3.5, preferably 2.0 to 3.0. When used together, the pH can be easily adjusted at the beginning of treatment liquid preparation. Furthermore, when adding each of the above-mentioned chemicals and the like to seawater, if means such as stirring are used, the pH can be adjusted more effectively. Further, it is preferable that each drug according to the present invention be dissolved in seawater at room temperature, that is, in the range of 4 to 20°C. Next, the seaweed nets from the seedling-raising stage to the harvesting stage are immersed in the algaecide treatment solution prepared by the above procedure.The immersion cycle is usually 7 to 10 days, and the treatment time is determined by the water temperature of the treatment solution, the seaweed It varies depending on the growth condition of the seaweed, the state of algae attachment, the severity of the seaweed disease, etc., but generally it takes 1 to 10 minutes at the bud stage and 5 minutes at the mature stage.
The standard time is about 30 minutes. In such an algaecide method of the present invention, when the above operations are performed using the same treatment liquid, the treatment liquid in the aquarium is taken out and reduced depending on the number of treatments;
The fumaric acid or fumaric acid-based treatment liquid according to the present invention continues its dissolving action in seawater one after another from a bag containing the treatment agent, so that the algicidal component in the seawater is always saturated. Therefore, the amount of treatment liquid can be restored simply by adding new seawater, and the PH value in the treatment tank is maintained within an appropriate range regardless of the increase or decrease in the amount of treatment liquid. Next, examples according to the present invention will be described. Example 1 Powdered fumaric acid was sealed in a rayon paper bag (height 10 cm x width 6 cm) made of the following material, and immersed in seawater 1 in an aquarium to continue dissolving. Table 1 shows the changes in PH value measured.

[Table] That is, as shown in Table 1, fumaric acid is used as an algaecide, its concentration range is set to 0.5 to 5.0%, and the pH after immersing it in seawater for 5 to 10 minutes is 2.2.
It can be seen that the pH value is within the range of ~2.8, which is suitable for algaecide. Example 2 Using the treatment liquid obtained in the operation of Example 1, the number of treatments and the fluctuation of the PH in the treatment tank were investigated.
That is, in order to perform continuous treatment by repeating, and to check the stability of the PH of the treatment liquid depending on the number of treatments,
The amount of processing liquid taken out for each treatment is 10 times the original amount of liquid.
~30% (weight) was set, and the corresponding amount of seawater was replenished for each treatment, and the pH of the treated solution was measured 10 minutes after replenishment. In addition, measurements similar to those described above were conducted using various organic acids and inorganic acids other than fumaric acid shown in Table 3 for comparison. In the above case, liquid acids such as hydrochloric acid and sulfuric acid were mixed directly into seawater without using a container.

【table】

【table】

[Table] As can be seen from the results in Table 2, when fumaric acid is used, even if the seaweed net is put in and out of the same tank 10 times, the pH of the treated solution remains unchanged.
There is almost no change, therefore, even without additional addition of fumaric acid, which has been reduced in amount with the number of treatments, almost the same treatment conditions as at the time of initial adjustment can be maintained, and
Regardless of the number of treatments, algaecide treatment can be performed for the same amount of time. On the other hand, as shown in Table 3, if other organic acids or inorganic acids are used, the PH in the aquarium will gradually increase during the treatment process, so new addition of these acids will be necessary to adjust this. Not only do you need
This indicates that it becomes difficult to perform stable algaecide treatment because the treatment time and other factors associated with this addition must be changed each time. Example 3 100% seawater was placed in a water tank, and then two bags filled with 500 g of fumaric acid were each immersed in the tank, and 500 g of malic acid was added to adjust the treatment solution. Nori buds and green seaweed were each attached to the net at a length of about 4 to 6 cm, and two pieces of the seaweed net were immersed in the treatment solution as test samples to examine the treatment effect. That is, the seaweed net was repeatedly immersed in seawater at a water temperature of 15°C.
The immersion and removal operations were performed 5 times every 10 minutes, and the PH of the treatment solution was measured each time. Note that a stirring means was also used at this time. Further, the effectiveness was determined as follows by collecting each leaf body after the above-mentioned treatment operation and observing it with erythrosin staining.

[Table] In other words, even when fumaric acid is used as the main ingredient and malic acid is used in combination as another organic acid as in Example 3, the algicidal effect aimed at by the present invention can be suitably exhibited. It shows. Furthermore, when fumaric acid and other organic acids such as citric acid, tartaric acid, succinic acid, etc. were used in combination or two or more thereof, the same measurements as described above were performed for each, and the effect was almost the same as that in Example 3. The results were obtained. As described above, the algaecide method according to the present invention requires that an amount of fumaric acid exceeding a saturation amount be present in a treatment liquid such as seawater stored in a treatment tank in a state coated with a coating means having water permeability. , or the processing solution is coated with a water-permeable coating means, and the processing solution contains an amount of fumaric acid exceeding the saturation amount and the processing solution has a pH of 1.5 to
Since algaecide is performed by coexisting an organic acid in an amount of 3.5%, and immersing the treated object such as a fishing net in this treatment solution, it is possible to kill algae by immersing it in the seawater in the aquarium. Depending on the amount of fumaric acid added,
In addition to being able to adjust the treatment liquid to have an effective pH value, the pH of the treatment liquid can be maintained within a specific range regardless of the number of times the seaweed net, etc. is immersed in or taken out of the aquarium, making it possible to continuously and repeatedly kill the liquid. When treating algae, it is only necessary to replenish the amount of seawater that has been reduced by taking it out, and since a treatment solution with a suitable pH value is always available, long-term work is possible. Furthermore, since the fumaric acid, other organic acids, inorganic acids, inorganic salts, etc. are sealed in a container or shell with water passage holes, and immersed in seawater to dissolve, the fumaric acid or other organic acids can be directly dissolved. There is no contact between the seaweed fronds and crystals of acids, inorganic acids, inorganic salts, etc., and there is no local damage to the seaweed fronds during treatment, making it possible to obtain good results in algaecide.

[Brief explanation of drawings]

Figure 1 is a graph showing the relationship between the concentration of each organic acid in seawater and PH. 1... Fumaric acid, 2... Malic acid, 3... Tartaric acid, 4... Citric acid, 5... Monochloroacetic acid,
6... Malonic acid, 7... Maleic acid, 8... Oxalic acid, 9... Sulfuric acid, 10... Hydrochloric acid.

Claims (1)

[Scope of Claims] 1 Fumaric acid is present in a treatment liquid such as seawater stored in a treatment tank in a state in which it is coated with a water-permeable coating means in an amount exceeding the saturation amount, and in this treatment liquid An algaecide method characterized by immersing an object to be treated, such as a fishing net, which requires algaecide. 2. The algaecide method according to claim 1, which uses a sheet having water passage holes as the covering means. 3. The algaecide method according to claim 1, which uses an outer shell having water holes as a covering means. 4. The algaecide method according to claim 1, 2, or 3, which uses fumaric acid in tablet form. 5 0.5-10% of the processing liquid as fumaric acid
(w/v). 6 1 to 5% of the processing liquid as fumaric acid
(w/v). 7 In a treatment liquid such as seawater stored in a treatment tank, an amount of fumaric acid that exceeds the saturation amount when covered with a water-permeable coating means and a pH of the treatment liquid is 1.5 to 3.5.
A method for killing algaecides, which comprises coexisting an amount of an organic acid, and immersing an object to be treated, such as a fishing net, in this treatment solution, which requires algaecide. 8 Organic acids such as malic acid, citric acid, tartaric acid,
The algaecide method according to claim 7, which uses one or more selected from succinic acids.