JP2010084097A - Soil conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a soil conditioner having vegetables such as Brassica rapa var. peruviridis, Hordeum vulgare L., or Raphanus sativus L. as the object of application, excellent absorption inhibitory effects on cadmium in cadmium-polluted soil and further excellent growth promoting effects on the vegetables. <P>SOLUTION: The soil conditioner includes lherzolite baked at 600-725°C as an active ingredient. Since the lherzolite contains much magnesium silicate, and mobile cadmium in the soil can be converted into an immobile form, the cadmium absorption of the vegetables is inhibited. Furthermore, the growth promoting actions can be enhanced by baking the lherzolite within a specific temperature range. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a soil conditioner suitable for use in growth targeting sugar beet such as komatsuna, barley, or radish. More specifically, the present invention relates to a soil conditioner that suppresses the absorption of cadmium in crops and is excellent in its growth promoting effect.

There are many farms around the world that are contaminated with heavy metals such as cadmium contained in mine wastewater. Cadmium in crops produced by agricultural activities in these areas is harmful to the human body. For this reason, the WHO / FAO Codex Committee established a standard for cadmium content in crops in 2006, and in Japan it is an urgent task to improve soil improvement materials in order to reduce cadmium content. . Furthermore, it is conventionally known that soil contaminated with cadmium or the like deteriorates the growth of plants.
Conventionally, as disclosed in Patent Documents 1 to 3, using a calcium material as a soil improver, or as disclosed in Non-Patent Documents 1 and 2, using a lerzolite having a cadmium absorption suppression effect, etc. It has been known.

JP-A-48-52552 JP 2004-65192 A JP 2007-228978 A Okazaki, et al., “Suppression of Cadmium Absorption of Rice by Magnesium Oxide Material (1) Cadmium Adsorption Characteristics of Magnesium Oxide Material” Abstracts of Annual Meeting of the Japan Society of Agricultural Civil Engineers (2-66) pp.260-261, 2006 Tetsuro Kikuchi et al., “Suppression of Cadmium Absorption in Rice by Magnesium Oxide Material (2) Inhibition of Cadmium Absorption in Rice by Application of Magnesium Oxide Material (Field Experiments)” .258-259, 2006

However, the method using a calcium material as disclosed in Patent Document 1 and the like has the disadvantage that it is easy to be leached due to rain and needs to be applied every year. In this regard, as disclosed in Non-Patent Document 1 and the like, the one containing lherzolite as an active ingredient has no inconveniences as the calcium material, is durable, has a high cadmium absorption suppression effect, and is inexpensive. Moreover, since it is highly effective as a fertilizer rich in magnesium, it has been attracting attention, and there is a need for an enhanced growth promoting effect.
Then, this invention makes it the objective to provide the soil improvement agent which further improved the growth promotion effect about the soil improvement agent which uses the lherzolite excellent in the cadmium absorption inhibitory effect as an active ingredient.

As a result of diligent research to achieve the above object, the present inventors, by firing the lherzolite at a specific temperature, have a remarkably superior effect of suppressing cadmium absorption compared to a conventional lherzolite that has not been fired. At the same time, it was found that a soil conditioner having a significantly enhanced growth promoting effect can be obtained.
The soil improver of the present invention has been made based on the above findings, and as described in claim 1, contains a lherzolite baked at 600 to 725 ° C. as an active ingredient.
The soil conditioner according to claim 2 is characterized in that, in the soil conditioner according to claim 1, the particle size of the lherzolite is 0.01 to 5.0 mm.
The soil conditioner according to claim 3 is the soil conditioner according to claim 2, wherein the lherzolite is pelletized.
In addition, the soil conditioner according to claim 4 is characterized in that, in the soil conditioner according to any one of claims 1 to 3, sugar beet is an application target.
A soil conditioner according to claim 5 is the soil conditioner according to claim 4, wherein the sugar beet is komatsuna, barley, or radish.

  Peridotite is a basic rock containing a large amount of magnesium silicate. By applying lherzolite, a powder, to cadmium-contaminated soil as a soil conditioner, the growth of sugar beet is greatly improved, and mobile cadmium in the soil is reduced. It has been conventionally known that the cadmium content of sugar beet is lowered because it can be changed to an immobile form. And the growth promotion effect | action can be greatly improved by baking a lherzolite at 600-725 degreeC like this invention.

The soil conditioner of the present invention is characterized in that it contains a lerzolite fired at 600 to 725 ° C. as an active ingredient, and if the firing temperature is less than 600 ° C. or exceeds 725 ° C., significant growth promotion is achieved. There is no effect. Therefore, it is essential to set the firing temperature of the lherzolite to 600 to 725 ° C.
The firing is preferably carried out for about 1 hour by putting a fine powder of lherzolite, which is generated when collecting a lherzolite rock from a lherzolite quarry, with a dust collector or the like, into an electric furnace. The firing time at this time is determined from the viewpoint of cost effectiveness of the input energy required for firing, and the firing time is not limited to about 1 hour. In addition, the lherzolite may be stirred in a furnace during firing.

Moreover, it is preferable to use the said lerzolite as a particle size of 0.01-5.0 mm, and since the baking effect improves so that a particle size is finer, it is more preferable to use as 0.01-2.5 mm. The lherzolite grains may be those obtained by refining lherzolite rock with a crusher or a mill.
In addition to the use of the lerzolite after calcination as a granule itself, it can be used by pelletizing or liquid extraction.

  The soil conditioner of the present invention must contain the above-mentioned lherzolite as an active ingredient, but it is a general fertilizer-effect ingredient including bituminous (magnesium), silicic acid, lime (calcium), iron and the like. In addition, chemical fertilizers may be included.

The application target of the soil conditioner of the present invention is not particularly limited as long as it is a sugar beet, but includes spinach, cabbage, carrot, radish and the like, and is used for growing komatsuna, barley, or radish. Is preferred.
In addition, grains such as rice and wheat are not excluded from the application.

Next, examples of the present invention will be described with reference to comparative examples.
Example 1
As cadmium contaminated soil, cadmium contaminated soil was used downstream of the mine due to the flooding of the river into which the drainage flowed. In addition, Komatsuna (variety “Ajisai” Tohoku Co., Ltd.) was used as a growth target. Further, as the lherzolite, a lherzolite powder produced in Miyamori-mura, Kamaishi City, Iwate Prefecture was used. In this example, the lherzolite powder having a particle size of about 2 mm was baked (trade name: Electric Muffle, manufactured by ADVANTEC, FUM322FB, internal volume). : About 10 L, heater capacity: 3.2 kW, furnace temperature distribution accuracy ± 5 ° C.), set the temperature controller setting temperature on the panel surface of the baking apparatus to 725 ° C., and 1 hour What was baked was used.
Table 1 below shows the content (%) of the main components before firing of the lherzolite per unit mass.

  As shown in Table 1, the main component of Lerzolite is magnesium silicate and the others are iron, calcium, aluminum, etc., but it contains a small amount of nickel as a feature.

Next, using a 1 liter pot made of plastic (1 / 150,00 are), 1% by mass of the calcined lherzolite with respect to 1 liter of the soil, and further advanced chemical fertilizer (nitrogen: phosphorus: potassium = 10: 10: 10) ) 1g was mixed and put into the pot.
Next, the seeds of the komatsuna were sown directly on the soil, covered with soil, sprayed with tap water, and cultivated while controlling the temperature conditions in the glass greenhouse to be in the range of 20 to 35 ° C. In addition, the number of seeds was 6, and sowing was cultivated and thinning was performed so that there would be 3 strains when the true leaves were developed.

(Example 2)
Komatsuna was cultivated in the same manner as in Example 1 except that the amount of the baked lherzolite mixed with the soil was 2% by mass.

(Comparative Example 1)
Komatsuna was cultivated in the same manner as in Example 1 except that lherzolite having a baking temperature of 800 ° C. was used.

(Comparative Example 2)
Komatsuna was cultivated in the same manner as in Example 1 except that lherzolite having a firing temperature of 850 ° C. was used.

(Comparative Example 3)
Komatsuna was cultivated in the same manner as in Example 2 except that lherzolite having a baking temperature of 800 ° C. was used.

(Comparative Example 4)
Komatsuna was cultivated in the same manner as in Example 2 except that lherzolite having a firing temperature of 850 ° C. was used.

(Comparative Example 5)
Komatsuna was cultivated in the same manner as in Example 1 except that unfired lherzolite was used.

(Comparative Example 6)
Komatsuna was cultivated in the same manner as in Example 2 except that unfired lherzolite was used.

(Comparative Example 7)
Next, for control, Komatsuna was cultivated in the same manner as in Example 1 except that the soil was mixed with only the advanced chemical fertilizer without using lherzolite.

  In Examples 1 and 2 and Comparative Examples 1 to 7, cultivation was started at the same time using the same contaminated soil and the same Komatsuna seeds, and seedlings grown to about 3 cm were transplanted, followed by cultivation for 35 days.

Next, each cultivated komatsuna was harvested and washed in the order of tap water, RO water and MQ water. Next, the root part and the above-ground part (leaf part) were separated with a knife, and the above-ground part was put in a newspaper paper bag and dried in a ventilating dryer at 70 ° C. for 48 hours, and then the dry mass was measured. The result of comparing the dry mass of the above-ground part is as shown in FIG.
For reference, FIG. 2 shows a photograph showing the growth state of Komatsuna when 1% by mass of baked lherzolite is added, and FIG. 3 shows a photograph showing the growth state of Komatsuna when 2% by mass of baked lherzolite is added. .

  As is apparent from FIGS. 1 to 3, when the fired lherzolite of this example is used, the growth promoting effect is excellent as compared with the case of using unfired lherzolite or lerazolite fired at a temperature of 800 ° C. or higher. Was confirmed. Further, it was confirmed that the growth promoting effect was obtained in a small amount when using a lherzolite having a firing temperature of 725 ° C.

  Moreover, the above-ground part of dried Komatsuna was decomposed with nitric acid and perchloric acid, and the cadmium content was quantified by atomic absorption spectrometry. The results are shown in FIG.

As is clear from FIG. 4, it is clear that the fired lherzolite also exhibits an excellent cadmium absorption suppression effect, similarly to the unfired lerzolite.
Thus, according to the present invention, it is clear that a soil improver excellent in the growth promoting effect can be obtained while maintaining the cadmium absorption suppressing effect of the unfired lherzolite.

(Example 3)
Komatsuna was cultivated in the same manner as in Example 1 except that lherzolite with a firing temperature of 600 ° C. was used.

Example 4
Komatsuna was cultivated in the same manner as in Example 1 except that lherzolite having a baking temperature of 650 ° C. was used.

(Example 5)
Using lherzolite with a firing temperature of 725 ° C., Komatsuna was cultivated in the same manner as in Example 1 separately from Example 1.

(Comparative Example 8)
Next, for control, Komatsuna was cultivated in the same manner as Comparative Example 7 separately from Comparative Example 7 using soil mixed with only advanced fertilizer without using lherzolite.

  In Examples 3 to 5 and Comparative Example 8, cultivation was started simultaneously using the same contaminated soil and the same Komatsuna seeds, transplanting seedlings grown to about 3 cm, and then cultivating for 35 days.

Next, each cultivated komatsuna was harvested and washed in the order of tap water, RO water and MQ water. Next, the root part and the above-ground part (leaf part) were separated with a knife, and the above-ground part was put in a newspaper paper bag and dried in a ventilating dryer at 70 ° C. for 48 hours, and then the dry mass was measured. The result of comparing the dry mass of the above-ground part is as shown in FIG. Here, the growth state is different between the growth condition at the firing temperature of 725 ° C. in FIG. 1 and the growth condition of the same condition in FIG. 5, but this is due to the difference in the amount of sunlight, etc., because the cultivation period of both is different. It is intended only for the purpose of examining relative comparisons at each growth stage.
For reference, FIG. 6 shows a photograph showing the growth state of Komatsuna when 1% by mass of calcined lherzolite is added.

  As apparent from FIGS. 5 and 6, it was confirmed that when the fired lherzolite of this example was used, the growth promoting effect was excellent.

  Moreover, the above-ground part of dried Komatsuna was decomposed with nitric acid and perchloric acid, and the cadmium content was quantified by atomic absorption spectrometry. The results are shown in FIG.

  As is clear from FIG. 7, it is clear that an excellent cadmium absorption suppression effect is exhibited.

(Example 6)
Cultivation was carried out in the same manner as in Example 1 except that Komatsuna, which is the cultivated species, was replaced with radish (variety “Akamaru radish (Cherry Mate), Tohoku Co., Ltd.”).

(Example 7)
Japanese radish was cultivated in the same manner as in Example 6 except that the amount of the baked lherzolite mixed with the soil was 2% by mass.

(Comparative Example 9)
Japanese radish was cultivated in the same manner as in Example 6 except that lherzolite having a baking temperature of 800 ° C. was used.

(Comparative Example 10)
Japanese radish was cultivated in the same manner as in Example 6 except that lherzolite having a firing temperature of 850 ° C. was used.

(Comparative Example 11)
Japanese radish was cultivated in the same manner as in Example 7 except that lherzolite having a baking temperature of 800 ° C. was used.

(Comparative Example 12)
Japanese radish was cultivated in the same manner as in Example 7 except that lherzolite with a firing temperature of 850 ° C. was used.

(Comparative Example 13)
The radish was cultivated in the same manner as in Example 6 except that unfired lherzolite was used.

(Comparative Example 14)
The radish was cultivated in the same manner as in Example 7 except that unfired lherzolite was used.

(Comparative Example 15)
Next, for control, radish was cultivated in the same manner as in Example 6 except that it was not used with lherzolite and was used with soil mixed only with highly chemical fertilizer.

  In Examples 6 and 7 and Comparative Examples 9 to 15, cultivation started simultaneously using the same contaminated soil and the same radish seeds, transplanted seedlings grown to about 3 cm, and then cultivated for 60 days.

Next, the cultivated radish was harvested and the growth status was compared. FIG. 8 shows a photograph showing the growth state of Japanese radish when 1% by mass of baked lherzolite is added. FIG. 9 shows a photograph showing the growth state of Japanese radish when 2% by mass of baked lherzolite is added.
Furthermore, the harvested radish was washed in order of tap water, RO water, and MQ water. Next, it cut | disconnected with the knife at the root part and the leaf part, put the root part and the leaf part in the paper bag made from a newspaper each, and dried it in a 70 degreeC ventilation dryer for 48 hours, Then, dry mass was measured. The results are as shown in FIG. 10 (above ground) and FIG. 11 (root). Both the above-ground and root parts of radish are cultivated with lherzolite baked at 725 ° C., and the growth is accelerated. It has been shown that

  Nitrogen and perchloric acid were decomposed in the above-ground part and root part of dried radish, and the cadmium content was quantified by atomic absorption spectrometry. The results are shown in FIG. 12 (ground part) and FIG. 13 (root part). It is shown that the Cd content per unit mass of the radish cultivated with lerzolite baked at 725 ° C. for both the radish and root parts of radish is reduced.

(Example 8)
As shown in Table 1, the lerzolite before firing contains a large amount of magnesium oxide (MgO) that is important as a constituent element of plant chlorophyll. Furthermore, citrate-soluble magnesium oxide (C MgO) is absorbed by plants and becomes a fertilizer for growth. Therefore, Table 2 shows the results of comparison of components of total magnesium oxide (TMgO) and CMgO depending on the temperature at which the lherzolite is fired. The firing time at the firing temperature of each lherzolite was 1 hour. As the firing temperature increases, the content of T MgO tends to increase. However, it has been found that the content of CMgO, which is important for plant growth, has a peak when the burning temperature of lherzolite is 725 ° C.

Example 9
FIGS. 14 and 15 show the measurement results of the pH of the soil before and after cultivation of the radish of Examples 6 and 7 and Comparative Examples 9 to 15, and also the transition of the soil pH after 2 crops and 3 crops. The soil pH before the first crop of radish was 4.5 acidic soil, but after 1 crop, the soil pH became high and the calcined lherzolite was close to neutral in both 1% and 2% of the calcined lherzolite. The more the content, the higher the neutralization effect, which is considered to have an effect as a soil pH adjuster. It is said that Cd in soil is less likely to be absorbed by plants as soil pH is higher, and MgO contained in lherzolite has an effect of increasing soil pH, and as a result, it is considered that Cd absorption by plants is suppressed. It is done.

The graph which shows the growth promotion effect of Komatsuna of this invention Example 1 and 2 (1 mass% and 2 mass% addition of lherzolite) and a comparative example Photograph showing the growth promotion effect of Komatsuna of Example 1 of the present invention (added 1% by weight of lherzolite) and Comparative Example Photograph showing the growth promoting effect of Example 2 of the present invention (addition of 2% by weight of Lerzolite) and Komatsuna of Comparative Example The graph which shows Cd content contained per unit mass of the above-ground part of this invention Example 1 and 2 (1 weight% and 2 weight% addition of lherzolite) and the Komatsuna of a comparative example The graph which shows the growth promotion effect of Komatsuna of this invention Example 3 thru | or 5 (1 mass% of lherzolite addition) and a comparative example Photographs showing growth promoting effects of Komatsuna of Examples 3 to 5 of the present invention (addition of 1% by weight of Lerzolite) and Comparative Example The graph which shows Cd content contained per unit mass of the above-ground part of the Example 3 thru | or 5 of this invention (1 mass% addition of lherzolite addition) and the Komatsuna of a comparative example Photograph showing the growth promotion effect of Example 6 (1% by weight of lherzolite) of the present invention and radish Photograph showing the effect of promoting growth of Example 7 (2% by mass of Lerzolite) and radish of Comparative Example The graph which shows comparison of the dry mass of the above-ground part of Komatsuna of this invention Example 6 and 7 (1 mass% and 2 mass% addition of lherzolite) and a comparative example The graph which shows comparison of the dry mass of the root part of radish root of Example 6 and 7 of this invention (1 mass% and 2 mass% addition of lherzolite) and the comparative example The graph which shows comparison of Cd content contained per unit mass of this invention Example 6 and 7 (1 wt% and 2 mass% addition of lherzolite) and the ground part of the radish of a comparative example The graph which shows comparison of Cd content contained per unit mass of this invention Example 6 and 7 (1 wt% and 2 mass% of Lerzolite addition) and the root part of the radish of a comparative example The graph which shows the relationship of each calcination temperature in the case of Example 8 (1 mass% of lherzolite addition) of this invention, the frequency | count of application, and soil pH. The graph which shows the relationship between each baking temperature in the case of Example 8 (2 mass% addition of lherzolite) of this invention, the frequency | count of application, and soil pH.

Claims (5)

  A soil improver comprising, as an active ingredient, lherzolite baked at 600 to 725 ° C.   The soil improver according to claim 1, wherein the particle size of the lherzolite is 0.01 to 5.0 mm.   The soil improver according to claim 2, wherein the lherzolite is pelletized.   The soil conditioner according to any one of claims 1 to 3, wherein the preparation is applied to sugar beet.   The soil improver according to claim 4, wherein the sugar beet is Komatsuna, barley, or Japanese radish.