FR2819147A1 - CULTURE SUPPORT ELEMENT FOR VEGETATION OF SURFACES - Google Patents

Abstract

The invention concerns a cultivation supporting element forming a layer, designed in particular for revegetation of outdoor surfaces, said cultivation supporting element comprising a cultivation substrate wherein the roots of plants are entangled. The cultivation supporting element comprises at least a longitudinal deformable tubular element (16) for water transport, said deformable tubular element (16) having, an inlet designed to be connected to a water supply and at least transverse orifices through which water can flow out. The deformable tubular element (16) is arranged inside said cultivation supporting element and substantially parallel to the surface defined by said cultivation supporting element so that at least part of the water circulating in said tubular element (16) is diffused in said cultivation supporting element to irrigate it.

Description

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 The present invention relates to a culture support element forming a carpet, intended in particular for revegetation of exterior surfaces, said culture support element comprising a culture substrate in which the roots of plants are entangled.

 One area of application envisaged is in particular but not exclusively the revegetation of terraces or roofs for which the growing medium must be light enough not to weigh them down. Revegetation improves the exterior appearance of buildings and provides technical advantages such as thermal and sound insulation, regulation of the evacuation of rainwater or protection against ultraviolet radiation.

 Cultivation supports installed on terraces are well known and allow the cultivation of categories of plants capable of withstanding drought well and multiplying spontaneously. Among these categories are perennials, some bulbous, some grasses and sometimes some kinds of shrubs.

 However, these culture supports have a significant weight per square meter, which constitutes an overload for the supporting structures. In addition, they require a relatively large infrastructure to support the growing medium and to seal and drain rainwater, which further increases the weight for the supporting structures.

 An object of the present invention is to provide a growing medium which not only makes it possible to revegetate the external surfaces without applying too great a load to the load-bearing structures, but also makes it possible to cultivate on these surfaces all kinds of plants, including the plants which do not necessarily withstand drought.

 This object is achieved thanks to the fact that the elements of the culture support comprise a culture substrate in which the roots of plants are entangled and that each culture support element

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 comprises at least one longitudinal tubular element allowing the transport of water, said tubular element having, an inlet capable of being connected to a water supply and at least transverse orifices through which the water is capable of flow, and in that said tubular element is arranged substantially parallel to the surface defined by said culture support element so that at least part of the water circulating in said tubular element diffuses in said culture support element for irrigate.

 Thus, a characteristic of the culture support element resides in the irrigation and in the permanent irrigation mode of said culture support by said tubular element which makes it possible to deliver water to the plants planted on the culture support. in specified quantities. In this way, all types of plants can be cultivated on the culture medium, including plants requiring significant amounts of water to grow. In addition, the culture support elements according to the invention are relatively light and make it possible to vegetate surfaces for which the supporting structures are relatively weak.

 Advantageously, said tubular element comprises an outlet through which the water is able to flow, said outlet being capable of being connected to a collector. Thus, the part of the water which does not flow through the transverse orifices of the tubular element is collected, possibly to be reinjected at the inlet of said tubular element.

 According to a particular embodiment of the invention, said tubular element consists of a flexible conduit. In this way, each culture support element which comprises a tubular element and which forms a mat, is capable of being stored in rotation, which makes it possible to solve the problems of handling said element.

 According to a preferred embodiment of the invention, the plants, the roots of which become entangled in the culture substrate, are dead. Thus, the plants constitute a dry grassy mulch which avoids the

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 erosion phenomena and favor the germination of seeds or the rooting of cuttings.

 Preferably, the culture support element further comprises a flexible reinforcement structure inserted into said substrate and into said plant roots, disposed substantially parallel to the surface defined by said culture support element. In this way, the mechanical resistance of said culture support element is increased, in particular longitudinally, which makes it possible to fix said element at the highest end in the case of an arrangement on a sloping surface and to avoid that said element does not deform by elongation.

 According to a particularly advantageous embodiment, the culture support element further comprises a film forming an obstacle to the roots disposed against its lower surface opposite the surface having the aerial part of said plants. The film makes it possible to limit the thickness of the culture support element forming a carpet by preventing the roots of the plants from growing beyond the barrier constituted by the film. Advantageously, said film is substantially permeable to water, which avoids the stagnation of water in the thickness of the element and the rotting of plants.

 Preferably, said culture substrate, which the culture support element comprises, has a water retention power greater than unity. Thus, it makes it possible to constitute a reserve for the development of plants planted in the culture support element.

 Another object of the present invention is to provide a method of producing a culture support element forming a carpet comprising a culture substrate in which the roots of plants become entangled, said method comprising the following steps: a substrate is provided of culture ; a layer of said culture substrate is spread over a substantially flat surface forming an obstacle to the roots; at least one longitudinal tubular element allowing the transport of water is applied to said surface, during the spreading of said culture substrate,

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 said tubular element having, an inlet capable of being connected to a water supply and at least transverse orifices through which water is liable to flow, whereby said tubular element is inserted into said layer; sowing, during the spreading of said culture substrate, seeds capable of forming plants having roots; and at least water is injected into said tubular element during the growth of said plants so as to accelerate said growth, whereby a transportable culture support element is obtained in which irrigation means are inserted.

 Thus, a characteristic of the process for producing said culture support element resides in the method of inserting the tubular element into said culture support by applying the tubular element to the surface at the same time as spreading. of the culture substrate. In addition, another characteristic of the production process is in the plant cultivation method according to which water is injected into the tubular element so as to make them grow but also so that said tubular element is not flattened by the development of the roots which enclose it and which would cause its obturation.

 According to a preferred embodiment of the invention, the growth of said plants is stopped by means of a non-persistent phytocide when they have reached a determined development, whereby a virgin culture support element is obtained. The plants thus constitute organic materials capable of promoting the development of other plants planted on the virgin culture support element.

 Advantageously, a culture substrate is provided having a water retention power greater than unity so as to allow water retention for the development of plants planted in said culture support element.

 According to a particularly advantageous embodiment of the invention, said layer of said culture substrate is spread on a film substantially permeable to water and forming an obstacle to said roots. In this way, we limit the development of plant roots to

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l'épaisseur dudit élément de support de culture et on évite la stagnation de l'eau dans cette épaisseur qui pourrait conduire au pourrissement des végétaux.

the thickness of said culture support element and the stagnation of water in this thickness is avoided, which could lead to the rotting of plants.

 Advantageously, during the spreading of said substrate, a flexible reinforcing structure is applied to said surface, substantially parallel to it. Thus, when one manipulates the culture support element and applies it on sloping surfaces, it retains its longitudinal dimensions.

 Preferably, said tubular element formed of a flexible conduit is applied to said surface by unwinding a continuous winding previously produced from said flexible conduit. In this way, it is easy to produce long lengths of culture support elements continuously without having to make a connection.

 According to an advantageous feature, said inlet of said tubular element is connected to a water supply so as to inject water into said tubular element during plant growth, whereby the water flows through said transverse orifices and the roots of said plants grow around said tubular element. The roots grow significantly around the perimeter of the tubular element, because the contribution of water is more important there.

 A third object of the present invention is to provide an installation intended for the continuous production of culture support elements comprising a culture substrate in which the plant roots become entangled, said installation comprising a mobile machine. Said mobile machine comprises: means for spreading a culture substrate in a layer on a substantially flat surface forming an obstacle to the roots; means for applying to said surface, during the spreading of said culture substrate, at least one longitudinal tubular element allowing the transport of water, said tubular element having, an inlet capable of being connected to a water supply and at least transverse orifices through which water is liable to flow; and, means for sowing, during spreading

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 said culture substrate, seeds capable of forming plants having roots.

 Thus, a characteristic of the installation resides in the presence of means intended to apply the tubular element in the layer of culture substrate during its production.

 In a particularly advantageous manner, the installation comprises means for injecting at least water into said tubular element during the growth of said plants, in order to accelerate this growth and to keep said tubular element in expansion, so that the roots of the plants do not flatten it.

 Preferably, said means for applying said tubular element to said surface comprise a reel on which is wound a continuous flexible conduit. In this way, long lengths of culture support element can be made continuously. Advantageously, said mobile machine comprises means for applying to said surface, substantially parallel to it, a flexible reinforcing structure so as to be able to reinforce the mechanical stability of the culture support element in particular in extension.

 Another object of the present invention is to provide a use of culture-forming support elements forming a carpet, in accordance with the invention, for revegetating external surfaces, said elements being applied to a support layer of which at least the face in contact with said elements is permeable to water and allowing the free circulation of water at least parallel to said face. Thus, the culture support elements, applied side by side on the surface to be planted, are irrigable by the tubular elements which they comprise.

This irrigation consists in moistening the culture support elements so that the water diffuses by capillarity in all of the elements. On the other hand, precipitation water passes through the support elements and is capable of passing through the film disposed against the lower surface opposite the surface presenting the aerial part of the plants to flow into said support layer, at least the face of which is in contact.

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 with said support elements is permeable to water. In this way, the precipitation water does not stagnate in the culture support elements which prevents the rotting of plants, and it is capable of being temporarily stored in said support layer in order to moisten said support elements and to supply plants with waters.

 According to a preferred embodiment of the invention, the tubular elements are connected to water supply means for irrigating said culture support elements and advantageously, these water supply means are controlled by means for measuring the humidity level of said culture support elements. In this way, the water ratio necessary for plant growth is controlled by the humidity level of the culture support elements, when this humidity level is lower than a first determined limit, the water supply means are triggered. and when the humidity level is greater than a second determined limit, the water supply means are stopped.

 Other features and advantages of the invention will emerge on reading the description given below of particular embodiments of the invention, given by way of indication but not limitation, with reference to the appended drawings in which: - Figure 1 is a partial schematic perspective view of a culture support element according to the invention; FIG 2 is a sectional view along the plane tt-tt of Figure 1; and, - Figure 3 is a schematic profile view of the installation for the implementation of the production method of the culture support element according to the invention.

 Figures 1 and 2 illustrate a culture support element having a horizontal film 10, extending longitudinally along F, on the first face 11 of which is disposed, longitudinally, a layer 12 of culture substrate, in which is inserted a textile reinforcement structure 14 substantially parallel to said film 10 and an element

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 tubular 16 also parallel to said film 10, the assembly being secured by the roots 18 of plants 20 which become entangled in the thickness of the layer 12 of culture substrate.

 The film 10 is made of flexible plastic and it has microperforations not shown passing right through, uniformly distributed over its surface. These microperforations allow the water, which by gravity comes into contact with the first face 11 of the film, to pass through the film 10 and to lead into its second face 22.

Advantageously, the film 10 has a thickness of less than 100 mm and it is made of opaque polyethylene.

 The film 10 has the particularity of obstructing the roots 18 of the plants 20 which develop in the layer 12 of the culture substrate.

 The latter consists of a compost of finely crushed and graded softwood bark whose bark section is less than 10 mm2. Obviously, any other growing medium can be used. However, the substrate must have a water retention capacity greater than unity so as to constitute a sufficient water reservoir for the good development of the plants which are planted there. Advantageously, the water retention rate of the culture substrate is greater than 2.

 The reinforcing structure 14 consists of a woven ply, or net, in which the spacing of the weft threads between them and the warp threads between them is substantially equivalent and of large size.

The distance separating two parallel wires is advantageously between 5 and 10 times the diameter of a wire. Any other ply, knitted or nonwoven which has the same mechanical tensile strength would be suitable. However, the woven web described above has the advantage of being inexpensive and of providing the culture support element at an advantageous cost.

 The woven sheet 14 is substantially parallel to the film 10 and embedded in the thickness of the layer of culture substrate 12. So

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 advantageously, the woven sheet is in contact with the film 10. However, it could be located at another position in the thickness of the layer 12 of culture substrate. It is understood that said woven sheet 14 provides said culture support element with dimensional stability and significant mechanical strength in a direction parallel to said element.

 In the layer 12 of culture substrate, arranged longitudinally, is inserted a tubular element 16 substantially parallel to said layer 12. The tubular element consists of a flexible plastic conduit and expanded so that its section is substantially the maximum section of the duct defined by its circumference.

 Advantageously, the conduit 16 consists of a strip of a plastic film whose two edges joined together are welded longitudinally so as to form a sheath. This embodiment makes it possible to provide a conduit at a particularly advantageous cost.

 The conduit 16 has an inlet capable of being connected to a water supply and transverse orifices distributed over its entire length inserted into said culture support element. When the conduit 16 is under water pressure, part of the water which circulates therein flows through the transverse orifices, and moistens the layer 12 of culture substrate. The water diffuses by capillary action in all the portions of culture substrates located near the transverse orifices and the latter are distributed along the conduit so that the entire layer 12 of substrate is rapidly quickly and evenly moistened.

 The flexible conduit 16 has an outlet connected to a manifold so as to maintain the constant pressure in the conduit 16 so that the quantity of water delivered through the transverse orifices is also constant. The collected water can be reinjected into the food.

 The layer 12 of culture substrate, the woven sheet 14 and the conduit 16 are held together by the roots 18 of the plants which

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 entwine and which bind to form a single coherent and flexible layer. The film 10, for its part, more or less adheres to the layer 12 of culture substrate on the face opposite to the face of the layer 12 of culture substrate having the aerial stems of the plants 20.

 These plants 20 of the culture support element are likely to be dead and the aerial stems then constitute a dry grassy mulch which avoids the phenomena of erosion and promotes the germination of the seeds or cuttings which are planted in the support element. .

 Furthermore, the support element which is flexible, can be rolled up for storage and to facilitate transport.

 Reference will now be made to FIG. 3 to describe a mobile machine of the installation capable of implementing the method for producing the culture support element according to the invention.

 The mobile machine essentially comprises a main chassis 30 supported by a front roller 31 and a rear roller 32. A roller 34 of a film 33 having microperforations passing right through it and distributed over its entire surface is disposed in the vicinity of the roller 31. A roller 35 of a woven sheet 36 is placed in the vicinity of the roller 34.

 A third roller 37, on which a determined length of flexible conduit 38 is wound, is disposed in the vicinity of the roller 35.

le rouleau 31 permet d'appliquer sur le terrain 40 le film 33 issu du rouleau 34. Par ailleurs, un second rouleau plombeur 41 permet d'appliquer simultanément sur le film 33 la nappe tissée 36 issue du rouleau 35 et le conduit flexible 38 issu du rouleau 37. A first sealing roller 39 placed immediately behind

the roller 31 makes it possible to apply the film 33 from the roller 34 to the field 40. Furthermore, a second sealing roller 41 allows the woven web 36 from the roller 35 and the flexible conduit 38 from the simultaneous application to the film 33 roller 37.

 The means for spreading a layer culture substrate, disposed between the front and rear rollers 31 and 32 essentially comprise a feed hopper 42 situated above a drum 43 parallel to the rollers 31 and 32 and provided with angles 44

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 for driving the substrate 45 contained in the hopper 42. An inclined spreading plate 46 situated directly above the drum 43 makes it possible to produce a layer 47 of culture substrate 45 of reduced and constant thickness on the film 33 covered with the woven sheet 36 and the duct 38.

 The layer 47 is then compacted by means of the rear roller 32, then optionally a nonwoven film is applied to the layer 47. Furthermore, it is possible to seed the layer 47 of culture substrate, after the compaction of the layer 47 with means for sowing 48. However, it is preferable to mix the seeds of plants capable of generating roots with the culture substrate 45, which simplifies the mobile machine.

 By seed is meant seeds or cuttings capable of germinating or growing to give adult plants. Advantageously, ryegrass seeds are mixed with the growing medium 45 or any other grasses or mixture of perennial fodder grasses.

 Of course, any other type of plant is likely to be suitable, if it has a good capacity for developing roots to connect together the woven sheet, the conduit and the culture substrate so as to form a transportable culture support element.

 Culture support elements are produced forming strips of culture substrate layer arranged side by side by means of the mobile machine of determined widths. In certain configurations, when the width of the element is large, two flexible conduits spaced from one another are simultaneously applied to the film. Obviously, the number of flexible conduits is not limited to two, and it is possible, depending on the circumstances and more particularly on the width of the elements, to insert as many as necessary into the layer of culture substrate. Advantageously, the distance separating two flexible conduits is between 20 and 50 cm, for example 35 cm, so that the humidification of the culture support element is

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 relatively fast and homogeneous when the duct is under water pressure.

 The installation also includes means, not shown, for injecting water into the flexible conduits during the growth period of the plants previously sown or planted. Advantageously, the conduits are connected to the domestic water supply network. However, it is possible to use the water contained in any reservoir and to inject it into the conduits by means of a pump.

 According to a particular characteristic, water is injected into the flexible conduits at regular intervals during the growth of the plants, so as, on the one hand, to allow their growth by means of the water which flows through the transverse orifices and on the other hand to regularly maintain the flexible conduit in an expanded position so that the roots do not compress it and plug it. Advantageously, water is injected into the pipes between two and six times a day for a period of between one and ten minutes, for example four times a day for three minutes.

dans tout le substrat de culture et maintiennent ensemble la nappe tissée et le conduit qui est expansé. Thus, culture support elements are obtained forming solid and flexible mats in a period of between 8 and 10 weeks, for example 12 weeks. Plant roots have spread

throughout the growing medium and hold the woven web and the expanded conduit together.

According to a particular embodiment of the invention, the plants are destroyed before the use of the culture support elements by means of a powerful non-persistent phytocide of the glyphosate type so as to form a dry grassy mulch capable of promoting the germination or rooting of the plants which will be inserted into said culture support.

 Another object of the present invention lies in the use of the culture support elements thus produced for the revegetation of the external surfaces.

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"film à bulles". Le"film à bulles"est appliqué sur la surface à végétaliser de façon que sa face ou les bulles font saillies soit en contact avec les éléments de support de culture et que l'autre face, sensiblement plane et hermétique soit en contact avec la surface. Ainsi, un espace libre apparaît entre les bulles du"film à bulles", délimité par le film microperforé de l'élément de support de culture et par la surface sur laquelle font saillies les bulles. To do this, the culture support elements, previously wound up, are unwound side by side on a support layer of the "bubble film" type, arranged on the surface to be vegetated, so that the microperforated film of the culture support elements is in contact with the

"bubble wrap". The "bubble film" is applied to the surface to be vegetated so that its face or the protruding bubbles are in contact with the culture support elements and the other, substantially flat and hermetic face is in contact with the surface. . Thus, a free space appears between the bubbles of the "bubble film", delimited by the microperforated film of the culture support element and by the surface on which the bubbles protrude.

 In this way, the "bubble film" constitutes a draining layer in which, the water passing through the microperforated film, is capable of circulating when the culture support elements are exposed to precipitation. Furthermore, the "bubble film" constitutes a relatively economical draining layer compared to other types of draining layers using aggregates or filtrate supports.

 When the culture support elements are arranged on the surfaces to be vegetated, they are sown with seeds or with plants which will constitute the ornamentation of the surface. To allow the seeds to germinate or the plants to develop properly, a regular supply of water is necessary. To do this, connection means are mounted at the end of the flexible conduits so as to connect them to a water circulation network to irrigate the elements of the cultivation surface. Thus, one obtains vegetated surfaces on which a growing medium, irrigation means, water and plants whose total weight is between 20 and 40 kg / m2, for example 30 kg / m2, rest.

 Advantageously, the water supply network is dedicated to the installation, and a humidity sensor makes it possible to control the injection of water into the conduits when the water content of the culture support elements is insufficient. According to a preferential mode, the

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 sensor consists of a precision balance on which is disposed a portion of culture support element comprising a conduit connected to the installation's water supply network. The portion of the culture support element and the balance are arranged so as to undergo the same climatic conditions as the culture support elements. Thus, the supply network is pressurized when the balance measures a total weight below a determined threshold corresponding to a water content of the portion of limit culture support.

Claims (22)

 1. Culture support element forming a carpet, intended in particular for revegetation of exterior surfaces, said culture support element comprising a culture substrate in which the roots of plants are entangled, characterized in that it comprises at least one longitudinal tubular element (16) allowing the transport of water, said tubular element (16) having an inlet capable of being connected to a water supply and at least transverse orifices through which the water is capable of flow, and in that said tubular element (16) is arranged substantially parallel to the surface defined by said culture support element so that at least part of the water circulating in said tubular element (16) diffuses in said culture support element to irrigate it.  2. Culture support element according to claim 1, characterized in that said tubular element (16) comprises an outlet through which the water is able to flow, said outlet being capable of being connected to a collector.  3. Culture support element according to claim 1 or 2, characterized in that said tubular element (16) consists of one. flexible duct.  4. Culture support element according to any one of claims 1 to 3, characterized in that the plants (20), whose roots (18) become entangled in the culture substrate (12), are dead.  5. Culture support element according to any one of claims 1 to 4, characterized in that it further comprises a flexible reinforcing structure (14) inserted in said substrate (12) and in said roots (18 ) of plants (20), arranged substantially parallel to the surface defined by said culture support element. <Desc / Clms Page number 16>  6. culture support element according to any one of claims 1 to 5, characterized in that it further comprises a film (10) forming an obstacle to the roots (18) disposed against its lower surface opposite the surface presenting the aerial part of said plants (20).  7. Culture support element according to claim 6, characterized in that said film (10) is substantially permeable to water.  8. Culture support element according to any one of claims 1 to 7, characterized in that said culture substrate (12) has a water retention power greater than unity.  9. Method for producing a culture support element forming a carpet comprising a culture substrate (12) in which the roots (18) of plants (20) become entangled, characterized in that it comprises the following steps: - a culture substrate is provided; - A layer of said culture substrate is spread over a substantially flat surface forming an obstacle to the roots; - At least one longitudinal tubular element allowing water to be transported is applied to said surface, during the spreading of said culture substrate, said tubular element having an inlet capable of being connected to a water supply and to the fewer transverse orifices through which water is likely to flow, whereby said tubular member is inserted into said layer; - Sowing, during the spreading of said culture substrate, seeds capable of forming plants with roots; and in that at least water is injected into said tubular element during the growth of said plants so as to accelerate said growth, whereby a transportable culture support element is obtained in which irrigation means are inserted.  10. A method of producing a culture support element according to claim 9, characterized in that, in addition, the growth of said plants is stopped by means of a non-persistent phytocide. <Desc / Clms Page number 17>  when they have reached a determined development, by which a virgin culture support element is obtained.  11. A method of producing a culture support element according to claim 9 or 10, characterized in that a culture substrate is provided having a water retention power greater than unity.  12. A method of producing a culture support element according to any one of claims 9 to 11, characterized in that spreading said layer of said culture substrate on a film substantially permeable to water and forming an obstacle to said roots.  13. Method for producing a culture support element according to any one of claims 9 to 12, characterized in that, in addition, during the spreading of said substrate, one applies to said surface, substantially parallel to it, a flexible reinforcement structure.  14. Method for producing a culture support element according to any one of claims 9 to 13, characterized in that said tubular element formed of a flexible conduit is applied to said surface by unwinding a continuous winding previously produced of said flexible conduit.  15. Method for producing a culture support element according to any one of claims 9 to 14, characterized in that said inlet of said tubular element is connected to a water supply so as to inject water in said tubular member during plant growth, whereby water flows through said transverse orifices and the roots of said plants grow around said tubular member.  16. Installation intended for the continuous production of culture support elements comprising a culture substrate in which the plant roots become entangled, said installation comprising a mobile machine, characterized in that said mobile machine comprises: - means (42 , 43, 44,46) for spreading a growing substrate (45) in a layer on a substantially flat surface forming an obstacle to the roots; <Desc / Clms Page number 18>  - Means (37, 41) for applying to said surface, during the spreading of said culture substrate, at least one longitudinal tubular element (38) allowing the transport of water, said tubular element (38) having an inlet capable of being connected to a water supply and at least transverse orifices through which water is likely to flow; and, - means (48) for sowing, during the spreading of said culture substrate, seeds capable of forming plants having roots.  17. Installation according to claim 16, characterized in that it comprises means for injecting at least water into said tubular element during the growth of said plants.  18. Installation according to claim 16 or 17, characterized in that said means (37,41) for applying said tubular element (38) on said surface comprise a reel (41) on which is wound a flexible flexible conduit (38) continuous.  19. Installation according to any one of claims 16 to 18, characterized in that, in addition, said mobile machine comprises means (35,41) for applying to said surface, substantially parallel to it, a flexible reinforcing structure (36).  20. Use of culture support elements for revegetating exterior surfaces according to any one of claims 1 to 8, characterized in that said elements are applied to a support layer of which at least the face in contact with said elements is permeable to water and allowing the free circulation of water at least parallel to said face.  21. Use of culture support elements for revegetating external surfaces according to any one of claims 1 to 8, characterized in that the tubular elements are connected to water supply means for irrigating said elements. culture medium. <Desc / Clms Page number 19>  22. Use of culture support elements according to claim 21, characterized in that the water supply means are controlled by means for measuring the humidity level of said culture support elements.