ORGANIC TOP SOIL COMPOSITION USEFUL FOR GROWING OF SEEDING AND TOP SOIL MAT MADE OF THE COMPOSITION TECHNICAL FIELD The present invention relates to an organic bed soil composition for use in growing of seedling, which comprises a seedling-growing organic material and a paper fiber, as active ingredients, and to a bed soil mat formed from the composition and a preparing method of the mat.

BACKGROUND ART The prior seedling-raising bed is obtained by putting seedling-raising powdery bed soils or seedling- raising sheets in a box, sprinkling water, seeding the bed soils or sheets with seeds, and covering the seeds with soils. Thus, such a bed has problems in that it is complicated to prepare and requires much labor for its use.

In order to improve such problems, there have been made various attempts to provide either seedling- growing bed soil compositions as a substitute for the bed soil, or methods of the preparation of seed- attached sheets or papers, nursery boxes, nursery sheets or the like. As a weight of the seedling- growing bed approximates to 5-6kg including a weight of the nursery, heavy labor is imposed on a farmer advanced in age. For this reason, a light bed soil was proposed. This is prepared by adding mellow chaff, zeolite and perlite, etc. to a horticulture bed soil (peat or coconut shell powder, etc.), and largely supplied in the form of a unit package containing a suitable amount of water as in the case of organic composts. However, because such a light bed soil is only an alternative to the general bed soil, it needs to be personally formed into the seedling-growing bed

by a user, according to the same method as the case of using the general bed soil. Thus, the preparation of the seedling-growing bed from the light bed soil is complicated. In addition, the light bed soil is expensive, and also it burdens a user with marketing cost.

In Japan, there was recently developed a substitute for the prior seedling-growing bed that has half as much weight as the prior bed soil and is inexpensive. This substitutional bed is prepared by subjecting mellow chaffs to compression processing and cutting the compressed material. However, due to a low productive efficiency of 100 pieces/hour, the substitutional bed cannot be overcame with respect to a productivity and a competitive price and also is limited in mass distribution.

Moreover, Korean Utility Model Laid-open Publication No. 97-53076 discloses the preparation of a nursery bed soil sheet, which comprises laying a vinyl sheet on the nursery; seeding a thin paper sheet with seeds; folding the paper sheet; and then sprinkling water on the paper sheets. However, such a bed soil sheet is disadvantageous in that the seeds stacked vertically zigzag on the paper sheet are much in useless and it requires a subsequent care. Also, as the bed soil sheet is a sheet type that is very weak for use as an alternative to the bed soil material, the practicality is problematic. In addition, the bed soil sheet has a difficulty associated with the management of seedling.

Korean Utility Model Laid-open Publication No. 98- 063774 discloses a non-woven fabric sheet for use in a transplanting nursery box. This sheet is reflected only by an extremely simple principle to prevent the root spreading of seedlings toward holes formed at the lower end of the nursery. However, this sheet involves

the inconvenience of treatments after being taken off for the transplanting of seedlings, and thus has problems to be solved for practical use. Regarding such problems, Korean Utility Model Laid-open Publication No. 99-33768 discloses a nursery box including a non-woven fabric. However, the latter publication is directed only to the non-woven fabric included in the nursery box.

A bed soil sheet was recently marketed that is prepared by subjecting horticulture bed soils to a compression molding and then drying completely the compressed material. However, owing to the compression molding, the bed soil sheet is very compact in its mat structure and has no pores formed therein, which makes the water or air permeability thereof is poor. Thus, the bed soil sheet cannot provide an environment suitable for germination of seeds and growing of the seedlings, so that it becomes unsuitable for use as a seedling-growing bed for germination of seeds and raising of the seedling. Moreover, the mat structure is likely to be broken due to its insufficient breaking strength. Additionally, due to properties of the horticulture bed soil and the compression system thereof, an excessive production cost is needed, and mass production and distribution cannot be realized.

Furthermore, Korean Utility Model Laid-open Publication No. 99-135756 discloses a slope-protecting mat including lawn seeds. The disclosed mat is characterized by a web layer consisting of irregular spaces formed between vegetable monofilaments. For the formation of the web layer, the vegetable monofilaments are deposited in the non-woven state on a top layer of a vegetable adhesive layer applied on the surface of a non-woven fabric. According to the latter publication, the spaces formed within the mat act as air vents so that they stabilize the germination rate and time of

lawn seeds. However, the disclosed mat is prepared by adhering the vegetable filaments to be entangled one another, on the non-woven fabric substrate with the adhesive.

Accordingly, there is a need to provide a seedling-raising bed soil mat which has excellent air and water permeability to make germination of seeds and raising of the seedling easy, and which is high in breaking strength and light in weight to render its delivery characteristic excellent. In addition, there is a need to provide a method of preparing the seedling-growing bed soil mat at a low cost and a high productivity.

DISCLOSURE OF INVENTION The present invention is directed to an organic bed soil composition for use in raising of seedling, comprising a seedling-growing organic bed soil material and a paper fiber, as active ingredients. Also, the present invention relates to an organic bed soil mat formed from the inventive composition and a preparing method thereof, which has excellent air and water permeability to make germination of seeds and raising of the seedling easy, and which is high in breaking strength and light in weight to render its delivery characteristic excellent. The preparing method of the mat according to the present invention is advantageous for industrialization, as it permits mass production within a short time using a vacuum forming method and thus has a high productivity.

Another object of the present invention is to provide an organic bed soil composition for use in raising of seedling, comprising a seedling-growing organic material and a paper fiber, as active ingredients, with the organic material and the paper fiber being present at a weight ratio of 60 : 40 to

90 : 10.

Further object of the present invention is to provide an organic bed soil mat for use in raising of seedling, which is prepared by subjecting the bed soil composition to vacuum forming and which is characterized by high porosity and thus, high air and water permeability, light weight and high breaking strength.

Also, other object of the present invention is to provide a method for preparing an organic bed soil mat for use in raising of seedling, which comprises: a first step of adding water and microelements to an organic material and a paper fiber, stirring and dissociating while adjusting the pH to obtain a mixture; a second step of introducing and immersing said mixture in a mat-forming tank, vacuum sucking moisture to form a mat on the vacuum suction mold; and releasing the mat from the vacuum suction mold; and drying the released mat.

Still, another object of the present invention is to provide a bed soil mat for use in raising of seedling, which comprises a bed soil composition and seeds, the bed soil composition comprising a seedling- growing organic material and a paper fiber. Also, the present invention provides a multi-layer bed soil mat comprising a first mat layer containing seeds, and a second mat layer not containing seeds.

Yet, other object of the present invention is to provide a method for preparing an organic bed soil mat for use in raising of seedling, which comprises the steps of: stirring and dissociating a seedling-growing material and a paper fiber in water while adjusting a pH of the mixture to 6-6.5 to make a mixture of a bed soil composition; adding seeds to the mixture ; introducing the suspension in a mat-forming tank ; immersing a vacuum suction mold in the mat-forming

tank ; applying vacuum to the suspension through the vacuum suction mold to form a first mat layer containing the seeds on the vacuum suction mold ; superposing a second mat layer not containing the seeds, on the first mat layer containing the seeds ; and subjecting the resulting mat structure to vacuum forming.

BRIEF DESCRIPTION OF DRAWINGS The above and other objects and aspects of the invention will be apparent from the following description of embodiments with reference to the accompanying drawings, in which: Fig. la schematically shows a bed soil mat of the present invention consisting of only a bed soil composition of the present invention ; Fig. lb schematically shows a seed-containing bed soil mat according to the present invention ; Fig. 2a is a schematic sectional view showing a seedling-raising organic bed soil mat according to the present invention, the mat consisting of a seed- containing mat layer and a seed-not containing mat layer; Fig. 2b is a schematic perspective view of the mat according to Fig. 2a ; Fig. 3 is a schematic sectional view of a vacuum suction mold which comprises a mold body; a mat-shaped cavity formed on the upper portion of the mold body; air vent holes through which air may be sucked from the cavity ; a grille which is mounted all over the inner surface of the cavity and on which a bed soil composition is adhered detachably; an air pipe by which the cavity may be communicated with a vacuum pump and an aluminum plate serving to support the mold ; Fig. 4 is a schematic sectional view showing a releasing mold serving to release a mat formed on the

grille of Fig. 4, which releasing mold is almost identical to the forming mold of Fig. 4, but is of small hole number.

Fig. 5 is a photograph showing a rolled mat of the present invention, which was seeded with rice seeds and then maintained for 9 days under an environment in which the rice seeds may be germinated and raised ; and Fig. 6 is a photograph showing a mat of the present invention, which was seeded with rice seeds and then maintained for 13 days under an environment in which the rice seeds may be germinated and raised.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is directed to an organic bed soil composition for use for raising of seedling, which comprises, as active ingredients, a seedling- raising organic material permitting germination of seeds, and a paper fiber. Also, it relates to an organic bed soil mat formed from the bed soil composition of the present invention, and a preparing method of the mat.

In one embodiment, the present invention provides an organic bed soil composition for use in raising of seedling, which comprises, as active ingredients, a seedling-growing organic material permitting germination of seeds, and to a mat formed from the same.

Examples of the organic material that can be used in the practice of the present invention include peat moss, coconut peat, or a combination thereof. Where the combination of peat moss and coconut peat is used as the organic material, the content of coconut peat in the combination must not exceed the content of peat moss in view of their properties. These organic materials are used mainly after impurity removal, fiber length adjustment, neutralization and selection. For

instance, the peat moss is used mainly after washing of its middle and high layer peat with water to remove ashes, drying, selection with a screen, adjustment to pH 6-6.5 and sterilization. The selection of peat moss provides organic materials having a 1-1.5 mm length.

The peat moss is a water-absorbing organic material and has an improved moisture-holding property, a high porosity of 85% or above by its fibrous material, a base exchange capacity (BEC) of 80-150 m. e./100 g, and a carbon-nitrogen ratio (C/N) of 15-25%. Thus, the peat moss physically endows the mat with air permeability and serves to prevent a beat phenomenon of the mat (namely, a twisting phenomenon) due to over- drying. Also, the peat moss occurs no secondary fermentation during raising of seedling by virtue of its cellulose component and has a lasting effect for the depression prevention and the plant growth maintenance. In addition, the peat moss is also ordinarily used as a horticulture bed soil or a material for seedling-growing pot.

Moreover, as a paper fiber, there is used a paper fiber obtained from a corrugated cardboard (carton box), a graft paper, or a waste newsprint paper. For example, a paper fiber is used which is obtained after removal of impurities, such as inks and synthetic resins, and pH adjustment. Among the paper materials, the graft paper is preferably controlled with respect to the contents of carbons, ashes, fiber, and lignin, etc contained therein, such that the plant growth is not hindered. In the prior art, there is a seedling- growing bed soil composition, which contains peat moss as an active ingredient. Such a prior composition is packed in the form of grains in a sack and marketed.

However, this prior composition has a shortcoming in that a user must personally prepare a mat using the composition. In addition, it has a problem in that a

mat prepared from the prior composition by compression molding is likely broken due to its low breaking strength. To solve such problems, the present invention employs the paper fiber. Where a pH of the paper fiber is adjusted to 6-6.5, it become an organic material similar to a standard of plant growth and is easily decomposed in soils, so that it is easily fermented and facilitates a soil improvement.

Examples of the paper fiber include a graft paper, a long fiber of corrugated cardboard, a short fiber material of newsprint, and the like. As the short fiber is varied in tension and beat phenomenon depending on its concentration and concentration gradient, it is highly critical that the paper fiber is contained at a ratio suitable for binding to the peat moss and for forming into a mat. Accordingly, the weight ratio of the paper fiber to the organic material is preferably 60: 40 to 90: 10, and more preferably 70: 30 to 80: 20. If the content of the paper fiber in the inventive bed soil composition or the bed soil mat formed from it is excessively high, the breaking strength of the resulting bed soil mat is too high such that the beat phenomenon occurs when the bed soil mat is over-dried during raising of seedling. This makes the germination of seeds difficult and causes the root cutting of the germinated seeds. On the other hand, if the paper fiber content is excessively low, the resulting bed soil mat is easily broken due to its low breaking strength so that it is cannot be delivered and is deteriorated in marketability, whereby the low paper fiber content makes the preparation of mat impossible.

In one embodiment of the present invention, the bed soil composition for use in raising of seedling may additionally contain natural components, such as, for example, one or more components selected from the group consisting of chitosan, loess and activated carbon.

Loess serves to provide microelements such as iron and the like, chitosan serves to improve a quality of rice grain obtained from a rice seed and seedling, and activated carbon serves to adjust a pH of the bed soil composition and has a bactericidal action.

Furthermore, the present invention provides a bed soil mat for use in raising of seedling, prepared from the inventive bed soil composition, or provides a bed soil mat containing seeds. In one embodiment of the present invention, there may be provided either a bed soil mat consisting of only one layer comprising the inventive bed soil composition and the seeds (mono- layer mat), or a bed soil mat consisting of a first mat layer comprising only the inventive bed soil composition, and a second mat layer comprising the inventive bed soil composition and the seeds (multi- layer mat). In the latter case, in order to prevent a suspension for the formation of the first layer from being mixed with the seeds of the second mat layer due to floatation of the seeds when superposing the suspension for the first mat layer on a suspension for the second mat layer, a concentration of the bed soil composition in the suspension for the first mat layer not containing the seeds is preferably higher than that of the bed soil composition in the suspension for the second mat layer containing the seeds. More preferably, the seed-containing solution for the second mat layer is prepared in such a manner that the concentration of the bed soil composition in the solution is in the range of 1.5 to 2 % (wt/wt), whereas the seed-not containing solution for the first layer is prepared in such a manner that the concentration of the bed soil composition in the solution is in the range of 2 to 5 % (wt/wt). The organic bed soil composition and the bed soil mat according to the present invention can be used for raising seedlings of all plants, including

a rice plant, a lawn, or a reed. Also, the organic bed soil composition according to the present invention may be personally used for raising of seedling by a user as a substitute for the general bed soil. Furthermore, it is possible to prepare either a mat using only the bed soil composition not containing the seeds, or to prepare a bed soil mat containing the seeds using the bed soil composition containing the seed. According to one embodiment of the present invention, a rice seedling-growing bed soil mat is seeded with rice seeds such that it is used commonly for direct sowing, and raising of young seedlings and medium seedlings. Then, the seeded bed soil mat is subjected to a forming process and used for transplanting and direct sowing of the rice plant. Also, a lawn seedling-growing bed soil mat may be used as a light piece of sod directly after the lawn seedlings are raised. As the formed mat contains all nutrients necessary for sterilization and growing of seedlings, the raising of seedlings in the mat is achieved by supply of only water and seeds into the mat. In the case of the bed soil containing the seeds, supply of only water into the mat is sufficient for raising of seedlings.

The bed soil mat formed using a solution containing a bed soil composition at a concentration of 1.5% to 2%, according to one embodiment of the present invention, exhibited a breaking strength of 3.26 to 3.64 kgf/cm2 as measured according to a test method of KS M 70 17-90 by Korean Institute of Commodity Test and Research. Also, if the concentration of the bed soil composition is varied, a dry breaking strength of the resulting mat is changed. A dry breaking strength suitable to endow the mat with proper delivery and germination properties is 1 to 5 kgf/cm2. The breaking strength is decreased when the mat contains the seeds.

Such a decrease in breaking strength is due to the

seeds contained in the mat, and is acceptable.

However, in order to improve a delivery characteristic of the mat, it is preferred to superpose a bed soil mat layer not containing seeds on the upper or lower surface of the seed-containing bed soil mat layer.

More preferably, the bed soil mat layer not containing the seeds has a higher bed soil composition concentration than that of the bed soil mat layer containing the seeds. Because of this, the seeds contained in the seed-containing mat layer are not floated on the upper layer during superposing of the seed-not containing mat layer, thereby increasing a breaking strength of the resulting bed soil mat.

In particular, in the case of the bed soil mat containing the seeds, it is prepared from a bed soil for a paddy rice and seeded with the seeds. Thus, as it can eliminate the bed soil refining and sorting, and sowing processes that require the most cost and labor in raising of seedling, it can reduce labor and cost.

In addition, it is advantageous in that it can provide solid seedlings by virtue of an improvement in water and air permeability. In the case of direct sowing, the bed soil mat buried with the seeds can be directly planted in itself. Thus, as the spot seeding type direct sowing can be made without the use of separate machines or devices, the lodging and tangling of rice plants resulted from the line sowing type direct sowing or the broadcast planting type hand sowing are prevented, thereby achieving the smooth harvesting.

Accordingly, as a set drill and a stump are distinguished from each other even in the lodging caused by natural disasters, harvesting machines may be used for operations. Also, in the case of rice plant, the disease and insect pest control or the harvesting operation becomes easy, and costs and efforts required for raising of seedling are reduced.

In another embodiment, the present invention provides a method for preparing a bed soil mat from the inventive bed soil composition using a vacuum forming process. This method comprises the steps of: adding an organic material and a paper fiber to water to form a mixture; stirring and dissociating the mixture while adjusting a pH of the mixture to 6.0-6.5 ; introducing the pH-adjusted mixture in a mat-forming tank; immersing a vacuum suction mold in the mat-forming tank; applying vacuum to the mixture through the suction mold to form a solid mat on the suction mold; releasing the solid mat from the suction mold; and drying the released mat. In the step of forming the pH-adjusted mixture, one or more ingredients selected from the group consisting of microelements, activated carbon, chitosan and loess may also be added. A method of preparing an organic bed soil mat containing seeds is similar to the above method of preparing the organic bed soil not containing seeds. However, it has differences in that it contains the seeds and maintains a germination property of the seeds.

In one embodiment, the present invention provides a method for preparing an organic bed soil mat comprising the steps of: adding water to an seedling- raising organic material and a paper fiber to form a mixture ; stirring the mixture and adjusting a pH and concentration of the mixture ; providing a suction mold comprising a mold body, a cavity formed on the upper surface of the mold body and having a size and shape corresponding to the mat to be formed, a plurality of air vent holes through which air may be sucked from the cavity, and a grille which is mounted all over the inner surface of the cavity ; immersing the suction mold in a forming tank containing the pH adjusted mixture; subjecting the mixture to vacuum forming through the grille of the suction mold so that solids in the

mixture is adhered on the grille to form a mat; fitting the suction mold into a releasing mold, the releasing mold having a plurality of vent holes through which vacuum can be applied to the mat formed on the grille of the suction mold ; applying vacuum to the mat adhered on the grille of the suction mold through the holes of the releasing mold so that the mat is released from the suction mold and adhered on the lower surface of the releasing mold ; horizontally rotating the releasing mold above a conveyor belt moving toward a dryer so that the mat is dropped on the conveyor belt.

In another embodiment, the present invention provides a bed soil mat containing seeds additionally to the bed soil composition. This bed soil mat containing the seeds is prepared by a method comprising the steps of: (a) a first step of providing an organic bed soil composition containing a seedling-raising organic material and a paper fiber, the organic material and the paper fiber being contained at the weight ratio of 60: 40 to 90: 10, stirring and dissociating the composition in water and adjusting a pH of the composition to 6-6.5 to form a mixture ; (b) a second step of adding sterilized seeds to the mixture containing the bed soil composition at a concentration of 1.5-2% to form a seed-containing mixture; (c) introducing the seed-containing mixture obtained from step (b) into a mat-forming tank, immersing a suction mold in the mat-forming tank, applying vacuum to the seed-containing mixture through the suction mold so that solids in the mixture are adhered on the suction mold to form a first mat layer containing the seeds, superposing, on the first mat layer, a second mat layer containing the bed soil composition at a concentration of 2-5% wt/wt, the second mat layer not containing the seeds, subjecting the resulting mat to vacuum forming through a releasing mold so that the mat is adhered on

the releasing mold; (d) and releasing the mat from the releasing mold and drying the released mat.

The mixture containing the bed soil composition is provided in two forms, namely, the mixture containing the seeds, and the mixture not containing the seeds.

The seed-containing mixture contains the bed soil composition at a low concentration of 1.5-2% (wt/wt), whereas the seed-not containing mixture contains the bed soil composition at a high concentration of 2-5% (wt/wt). This difference in the bed soil composition concentration is to prevent the seeds of the seed- containing layer from being floated and mixed with the second mat layer not containing the seeds when superposing the second mat layer on the first mat layer containing the seeds. The seed-containing bed soil mat, when being supplied with only water and adjusted to conditions suitable for germination, can germinate the seeds without needs of additional conditions. In the mat-preparing method of the present invention, both the bed soil composition and the seeds are preferably used after sterilized. The bed soil composition may be sterilized by treatment with methylene serving to prevent a black shank, such as a Lidomil commercially available from Sung Bo Agricultural Chemical Co., Korea. The seeds may be sterilized by treatment with Prochloraz available from Novatis Agrochemical Co.

Moreover, the bed soil composition comprising the organic material and the paper fiber is subjected to intensive stirring and dissociation in order to form a homogeneous solution by a complete dissolution of the fiber. Thus, since addition of the seeds during the stirring and dissociation step will result in a very low germination rate due to a damage of the seeds, the seeds must be added after preparing the homogeneous solution of the bed soil composition. Also, during the step (b) of forming the seed-containing mixture,

injection of air into the seed-containing mixture makes a concentration of the seeds in the mixture uniform.

This allows the formation of a mat containing the seeds at a uniform concentration when preparing the mat using the seed-containing mixture.

The mat not containing the seeds may be dried according to the conventional drying conditions.

However, if the organic bed soil mat containing the seeds as in the present invention is subjected to a hot air drying at high temperature, a problem will occur in that the seeds suffer from the heat injury and thus is remarkably reduced in their germination rate. For this reason, the mat is preferably dried with a warm air at a temperature of 30-36 °C in the drying step (d).

In the step of forming the bed soil composition- containing mixture, one or more ingredients selected from the group consisting of microelements, chitosan, loess and activated carbon may also be additionally added.

In one embodiment, the present invention provides a method of preparing a mat comprising a mixture of an organic material and a paper fiber, and seeds filled in the mixture, in which the organic material and the paper fiber are contained at a weight ratio of 60-90 : 40-10. This method comprises the steps of: mixing the organic material and the paper fiber with water and stirring the mixture ; mixing the seeds with the mixture to form a seed-containing mixture; providing a vacuum suction mold having a mold body, holes formed through the mold body, a grille disposed all over the inner surface of a cavity formed on the upper side of the mold body, the cavity being formed on the upper surface and having a shape and size corresponding to a mat to be formed ; immersing the vacuum suction mold in the seed-containing mixture ; applying vacuum the seed-containing mixture through the

grille of the vacuum suction mold in such a manner that solids in the seed-containing mixture are attached to the grille, thereby forming a first mat layer containing the seeds; superposing, on the first mat layer, a second mat layer comprising the bed soil composition at a higher concentration than that of the first mat layer without containing the seeds, using a vacuum forming process; fitting a releasing mold into the vacuum suction mold ; releasing the mat from the vacuum suction mold so that the mat is adhered into the releasing mold ; and releasing the mat from the releasing mold, thereby dropping onto a conveyor device moving toward a drying device.

The following examples are for further illustration purposes only and in no way limit the scope of this invention.

Example 1 10 kg of a sterilized composition consisting of 8 kg of peat moss or coconut peat and 2 kg of a paper fiber, adjusted to pH 6 was stirred and dissociated for in a pulper tank having one-ton capacity for 30 minutes to prepare a pulp solution containing the composition at a concentration of 1.5-2% by weight.

A pair of a suction mold having a cavity size corresponding to a bed soil size of 580 mm x 280 mm x 7 mm was sufficiently immersed in a forming tank containing the pulp solution. Vacuum (7.5 bar/m3) was applied to the pulp solution through the suction mold from a vacuum pump for one second so that solids in the pulp solution were cohesive while being adhered on the entire inner surface of the grille of the suction mold to a thickness of about 4 mm, thereby forming a mat on the grille. Then, the mat attached on the grille was subjected to the vacuum forming through a releasing mold so that the mat was adhered on the lower surface.

Then, the mat was dropped onto a conveyor belt moving toward a dryer. The mat thus formed had the water content of 60%, but was dried with a hot air at a temperature of about 100 °C. 48 Mats, which were contracted to have a size of 560 mm x 256 mm x 5.5 mm after drying, were obtained. Also, two pairs of suction molds could produce about 500 mats or more per hour from the pulp solution in the same tank.

Moreover, if the dried and contracted mats were put in a nursery box and fed with water, it was then restored to an internal size of the nursery box shortly, and also became an organic bed soil which holds moisture such that the seeds can be germinated and grown. As a time necessary for one time mat forming is 12 seconds, the application of the method as described above to the production system enables mass production without limit, as long as the number of suction mold used is increased.

Examples 2-6 Examples 2-6 were carried out according to the same procedure as described in Example 1, except that compositions set forth in Table 1 were used.

Measurement results of a breaking strength and a porosity for the formed mat are indicated in Table 1.

Table 1 Organic material Mat characteristics Peat moss Coconut Paper fiber Breaking (Kg) peat (Kg) (Kg) strength Porosity Example 1 80 0 20 Moderate Moderate Example 2 90 0 10 Weak High Example 3 70 0 30 Strong Low Example 4 60 0 40 Very strong Very low Example 5 65 15 20 Moderate Moderate Example 6 65 20 15 Weak High In the above Table 1, the breaking strength of the mat formed from the composition is graded into three grades of"weak","moderate"and"strong", and the porosity is graded into"low","moderate"and"high".

In the seedling-raising mat, the breaking strength of the moderate grade is preferred, and the increased porosity shows the better. In view of such two factors, it is most preferred that a mixing ratio of the organic material to the paper fiber is in the range of 80: 20 to 70: 30.

Example 7 To measure a variation in box weight according to a bed soil material before and after seeding, water was added to a bed soil of the present invention, the general bed soil from the rice field, Bunongsangt OTII (available from Bunongsangto Co., Korea) consisting of a fertilizer added to the general bed soil, and a carbonized chaff-containing bed soil (consisting of 60 w% carbonized chaff, zeolite, loess and fertilizer), respectively. To the box containing the respective bed

soils, seeds pregerminated by sterilization and immersion in water for two days were added at the amount of 280g/box. The weight of the used box is 630 g, and the seed is a rice seed. The dry bed soil weight before seeding, the covering soil weight and the total box weight after seeding were measured. Results are indicated in Table 2. Also, in Table 2, the total weight of the respective box is indicated in parentheses as a weight percent relative to the weight of the general bed soil. As to the weight of the water-containing box after seeding, the box containing the inventive bed soil composition weighed 3,612 g, which equals to 70% of the box containing the general bed soil (4,914 g). Also, the inventive mat itself weighed 150 g, whereas the general bed soil weighed 1100 g. Accordingly, the inventive mat is significantly light in weight. and thus easy to delivery.

Table 2 Dry bed soil weight before seeding Covering soil Total weight after Bed soil material (g/box) weight (g/box) seeding (g/box) Bunongsangto 1,970 2,600 5,102 (104%) General bed soil 1,492 2,122 4,194 (100%) bed soil of the present invention 750 794 3,612 (70%) Carbonized chaff--4, 604 (94%) Example 8 10 kg of a sterilized composition, which consists of 8 kg of peat moss or coconut peat and 2 kg of a paper fiber and was adjusted to pH 6, was stirred and dissociated in a pulper tank having one-ton capacity for 30 minutes to prepare a pulp solution containing the composition at a concentration of 1.5-2% by weight.

Further, another solution containing the bed soil composition at a concentration of 2-5 % by weight was prepared according to the above-described method and stored in a pulp tank. The pulp solution containing the composition at the relatively low concentration (1.5-2% by weight) was transferred to a forming bath, to which sterilized rice seeds were added at the amount of 350,000 grains (quantity corresponding to 50 mats) (for lawn seed, 37.5 g corresponding to 50 mats).

Then, the seed-containing solution was stirred with air blown from the bottom of the pulp tank.

A pair of a suction mold having a cavity size corresponding to a bed soil mat size of 580 mm x 280 mm x 7 mm was immersed sufficiently in the forming tank containing the low concentration composition solution.

Vacuum (7.5 bar/m3) was applied to the solution through the suction mold from a vacuum pump for one second, so that solids in the pulp solution were cohesive while being attached on the entire inner surface of the grille of the suction mold to a thickness of about 4 mm, thereby forming a seed-containing mat layer.

Then, the low concentration pulp solution in the forming tank is replaced with the high concentration pulp solution, and vacuum is applied to the solution so that a seed-not containing mat layer was superposed on the seed-containing mat layer to a thickness of about 2 mm thickness.

The mat consisting of the seed-containing mat layer and the seed-not containing mat layer was attached on a releasing mold by the application of vacuum and dropped onto a conveyor belt moving toward a dryer. The mat thus formed had the water content of 60%, but was dried by passage through a hot air drying tunnel at a temperature of about 35 °C in order to prevent the seed from being subjected to a heat injury and from containing moisture. 48 Mats, which were

contracted to have a size of 560 mm x 256 mm x 5.5 mm after drying, were obtained. Also, two pairs of suction molds could produce about 500 mats or more per hour from the pulp solution in the same tank.

Moreover, if the dried and contracted mats were put in a nursery box and fed with water, it was then restored to an internal size of the nursery box shortly, and also became an organic bed soil which holds moisture such that the seeds can be germinated and raised. As a time necessary for one time mat forming is 14 seconds, the application of the method as described above to the production system enables mass production without limit, as long as the number of suction mold used is increased.

Example 9 The bed soil mat prepared in Example 7, which was seeded with the rice seed, was maintained in a glasshouse or a vinyl house at a temperature of about 25 to 32 °C. A variation in a raised degree of seedlings according to a time elapsed after seeding was measured in terms of a plant length (a length of the original rice seedling), an infiltration length, a dry matter weight and a root formation degree, so that an ageing of the seedling-growing for each of the bed soils could be measured. Results are indicated in Table 3.

Table 3 At 8 days At 10 days after after seeding seeding At 13 days after seeding Dry matter weight Plant Infiltration (g/100 units) Root length length Plant formation Bed Soil Plant length (cm) (cm) (cm) length Root degree Bunongsangto 4.9 8.0 8.4 2. 1 0.845 0.361 +++ General bed soil 4.5 9. 7 10.8 2.1 0.799 0. 216 +++ bed soil of the present invention 4.5 8.0 8. 4 2.1 0.800 0.210 +++++ 60% carbonized chaff 4. 9 S. 2 8.9 2.1 0.733 0.202 ++ +++++ : very excellent ; ++++ : excellent ; +++ : good ; and ++: bad Seedlings at 9 days after being seeded in the inventive bed soil mat are shown in Fig. 5, and seedlings at 13 days after being seeded are shown Fig.

6. At 10 days after seeding, a plant length of young seedlings in the case of each of general bed soil, carbonized chaff and Bunongsangtoll was 9.7-8.0 cm, which is short as compared to a suitable plant length for transplanting of young seedlings. This short plant length can be overcame by addition of nutrients. At 13 days after seeding, the root weight was the highest in the case of Bunongsangt OTM, but the root formation degree was most excellent in the case of the inventive bed soil. As shown in Fig. 5, the young seedlings raised in the inventive bed soil mat exhibits the excellent root formation degree and thus are easy to transport and to transplant using automatic machines.