JP3784598B2

JP3784598B2 - Planting base material and planting method using plant carbide

Info

Publication number: JP3784598B2
Application number: JP2000009106A
Authority: JP
Inventors: 裕之高砂; 晴夫高山; 隆雄松元
Original assignee: Kajima Corp; Chemical Grouting Co Ltd
Current assignee: Kajima Corp; Chemical Grouting Co Ltd
Priority date: 2000-01-18
Filing date: 2000-01-18
Publication date: 2006-06-14
Anticipated expiration: 2020-01-18
Also published as: JP2001200541A

Description

【０００１】
【発明の属する技術の分野】
本発明は、植物性炭化物利用の法面緑化基盤材及び緑化工法に関し、とくに用地造成などの土木工事に伴って発生する法面（「のり面」と書かれることもある。）の緑化に用いる緑化基盤材に関する。ここに、植物性炭化物とは、木材、竹材、又は籾殻などの植物材料を炭化したものであり、典型的には木炭である。
【０００２】
本発明は、間伐材や籾殻などの未利用農林資源を、加熱・炭化して木炭や殻炭とした上でこれを緑化基盤材として使用することにより、それら未利用資源の有効活用の目的に供することもできる。
【０００３】
【従来の技術】
盛土又は地盤切取りによって生じた人工斜面が法面と呼ばれている（小橋澄治等、「のり面緑化の最先端」、株式会社ソフトサイエンス社、1995年、２頁）。裸の法面は、水が流れ易く、危険な斜面基質の崩落も起こり易いので、裸法面に対しては急速な安定化対策を施さなくてはならず、そのために緑化工事、即ち植物被覆を施す工事が必要となる。
【０００４】
法面緑化工事は、別途育てた苗木を法面に植え付ける苗木設置工や法面に植物の種子を播く播種工によって行われる。苗木設置工の一例においては、木本植物の苗木の根鉢を法面に固定した後、天然土壌及び／又は人工土壌からなる緑化基盤材と草本植物の種子・肥料・接合材等とからなる基材を法面の表面全体に貼り付け、法面を木本植物と草本植物との両者で覆う。播種工の一例においては、水溶性のポリビニールアルコール製の袋に、ピートモスの人工土壌からなる緑化基盤材と草本植物の種子とがパック詰めされた資材を、法面全体に設置し、種子から発芽・生育した草本植物によって法面を覆う。
【０００５】
これらの法面緑化工事の例では、苗木設置工及び播種工の何れにおいても、天然土壌及び／又は人工土壌からなる緑化基盤材が使われる。
【０００６】
ところで木炭は、農業の分野においては、地力増進法に基づき、主に透水性の改良を主目的とする土壌改良材として指定されている。木炭がもつ他の効果として、保水性の改良効果やミネラルの補給効果、微生物のすみかとしての効果がこれまでの試験研究により確認されている。
【０００７】
法面緑化においては、バーク堆肥等を主材料とした基盤材に木炭を混合した場合の施用効果について検証した例がいくつかある（木材炭化成分多用途利用技術研究組合、1994年）。その報告によると緑化植物の種類や条件によっては、その施用効果があるなどとしている。しかし、まだ検証した例が少ないのが現状であり、本発明で着目した木炭の粒径の違いによる木炭の特性の違いを踏まえた検証例は見あたらない。
【０００８】
このように従来、木炭が上壌改良材として利用される場合、木炭の粒径や粒径組成の違いによる木炭の性質の違い、及び発揮される土壌改良効果の違いについては留意されることは少なく、製造上や施工上の都合により粒径の大きいものから粉末状のものまで、雑多で不均一な粒径組成の木炭を利用するか、試験的に条件を揃えるためにふるい分けて使用するにとどまっていた。
【０００９】
【発明が解決しようとする課題】
バーク堆肥を主体とした法面緑化基盤材は、吹きつけ施工後、数日降雨がないと基盤表面が乾燥するにつれ、撥水性を帯びてくる傾向をもつ問題点がある。このような状態の基盤材は降雨時に雨水の浸透性の低下を引き起こすことが知られている。施工後１〜４週間は基盤材に配合された種子の発芽および初期成長の期間であり、この時期の水分条件はその植生の形成に大きな影響を及ぼす。従来、このような状態の基盤材に対しては何らかの方法で穴をあけ、雨水の入り込むスペースを作るなどの処置を施していたが、このような処置には、面倒で手間がかかる問題点がある。
【００１０】
そこで、雨水の浸透性を向上させる効果を持ち、しかも安価で白然生態系にも調和した資材が求められている。
【００１１】
また、景観上や生態系調和の観点から、岩盤法面やモルタル吹き付け法面など、環境条件の厳しい法面の緑化に対するニーズが高まっている。このような法面での緑化成立には水分条件が大きな要因となっている。緑化基盤材の保水性を高めるため、各種の高分子吸水ポリマーが開発され商品化されているが、これらのものは高価であり、より安価な資材が求められている。
【００１２】
木炭は植物性炭化物の代表的なものである。木炭の原材料には色々なものがあるが、山間地における間伐材を木炭として有効活用することは、資源の有効かつ高度な利用法として、また、中山間地の活性化にも期待されている。
【００１３】
間伐材から得られた木炭を法面緑化の基盤材の一部として有効活用する事は、山間地における木材資源を育成する過程で生じた余剰資源を、緑化による新たな緑の創造の際に有効活用するので、資源の循環利用の点で非常に合理的な利用方法と言うことができる。また、資材としても自然生態系に調和したものと言うことができる。
【００１４】
しかし、木炭など植物性炭化物を法面緑化基盤材に利用する際、単純に基盤材に混合するだけでは木炭の土壌改良効果が十分に活用できないだけでなく、さらなる利用の拡大・普及が期待できない。そこで、木炭など植物性炭化物の施用効果を明らかにすると共に、より高度な利用法を開発し、植物性炭化物の有効利用を促進していく必要がある。
【００１５】
【課題を解決するための手段】
上記問題点を解決するため本発明者は、木炭を土壌改良材として利用する場合、粒径の異なる木炭粒が異なる土壌改良材効果を発揮することに注目し、実験研究を重ねた。その結果、木炭などの植物性炭化物の粒径と土壌改良性能との関係に関する知見を得、その知見を利用することにより質の高い法面緑化基盤材を提供することに成功したものである。
【００１６】
粒状の植物性炭化物による保水性の改良効果について、粒径が異なる木炭の保水力を測定したデータを図５に示す。同図によれば、粒径４mm未満の細粒のものに比べ、粒径７mm以上の粗粒のものは保水力が約46％高く（4.7／3.2）、粒径４〜７mmの中粒のものは保水力が約65％高い（5.3／3.2）ことがわかる。これは粉末状の細粒木炭に比べ、中粒以上の大きな木炭片は、木炭特有の微細孔隙が顕著に形成されている事実に関連していると考えられる。
【００１７】
次に、木炭の粒径の違いによる土壌化学的特性の差異を測定・比較したものを表１に示す。同表によれば、粒径２mm以下の極細粒の木炭は、比較的粗い粒径２〜４mmの木炭と較べ、植物の栄養素を多く含んでいることがわかる。即ち、比較的粗い木炭に比し、極細粒の木炭は、交換性のカルシウムを約60％多く、交換性のマグネシウムを約２倍、交換性のカリウムを約40％多く含んでおり、植物の栄養素として重要な陽イオンを多く含んでいる。これは一般に言われるミネラルの補給効果に当たる部分であるが、このミネラル補給能力の点では、極細粒の木炭の方が比較的粗い木炭より効果が大きいことがわかる。
【００１８】
【表１】

【００１９】
このように、木炭の粒径により、その保有する土壌改良特性が異なる。つまり、細粒部ほどカルシウムやカリウム、リン酸など栄養素やミネラルの供給能が高く、中粒部は保水性、保肥力が高い傾向にある。この傾向は木炭以外の竹材、草炭、籾殻炭などの植物性炭化物においても同様であることが推測される。
【００２０】
そこで、緑化の対象となる場所の環境条件や目標とする植生などの条件に応じて、炭化物の粒径組成を任意に配合することで、植物性炭化物による各種土壌改良効果がより効果的に発揮されることにつながる。
【００２１】
本発明による植物性炭化物利用の法面緑化基盤材は、天然及び／又は人工土壌にピートモス、バーク堆肥、又はヤシガラを選択的に加えた又は加えない土壌材70−98容積％と、粒径５ mm 未満の細粒部及び粒径５ mm 以上の中粒部が土壌理化学的改良特性に応じた比率で含まれる粒状植物性炭化物２−30容積％とからなるものである。
【００２２】
好ましくは、前記植物性炭化物に、ミネラル供給能が高い粒径２mm未満の極細粒部及び粒径２mm以上５mm未満の細粒部と、保水性・保肥力が高い粒径５mm以上10mm未満の中粒部と、粒径が10mm以上で法面緑化基盤材の形成可能限度内の粗粒部とを、用途の土壌理化学的改良特性に応じた比率で含める。
【００２３】
また、法面緑化基盤材には、浸食防止材（剤）として用いられるものの中から、例えば木質繊維などファイバー類である養生材、例えばアスファルト乳剤である養生剤、例えばポリ酢酸ビニル溶液である粘着剤、例えばセメントである接合剤、及び例えばパーライトや高分子吸水材である保水材からなる群の中から選んだ一以上の添加物を加えることができる。
【００２４】
本発明による植物性炭化物利用の法面緑化工法は、前記添加物が含まれない又は含まれる法面緑化基盤材によって地盤の法面を覆い、その緑化基盤材を利用して該法面上に植物を育成してなるものである。
【００２５】
【発明の実施の形態】
実際の木炭など植物性炭化物の緑化基盤材全体に対する配合量は、２容積％から多くても30容積％までの間で選択するのがよい。緑化基盤材を実際に設置する場所における様々な自然条件やコスト的な条件に応じて、適切な植物性炭化物の配合量を慎重に選ぶ。
【００２６】
また、植物性炭化物の前記保水力やミネラル補給能力などの土壌理化学的改良特性は、炭化物の粒径の違いに応じて連続的に変化する。前記データは、植物性炭化物の細粒部及び中粒部の典型的な部分について実験的に求めたものである。木発明では便宜上、植物性炭化物の粒度について、粒径が10mm以上で法面緑化基盤材の形成可能限度以下のものを粗粒部、粒径が５〜10mmのものを中粒部、粒径が５〜２mmのものを細粒部、及び粒径が２mm未満のものを極細粒部とそれぞれ呼ぶ。
【００２７】
好ましい実施例では、植物性炭化物の配合量を、法面緑化基盤材全体に対して容積で10％とし、さらに植物性炭化物の種類とその粒度分布を、前記10％のうちの５％を粒径５mm以下の細粒木炭とし残余の５％を粒径５mm以上の中粒程度の木炭とすることにより、ミネラル補給効果と保水性改良効果とのバランスが取れた法面緑化基板材とする。
【００２８】
緑化する場所の水分条件が悪く、保水性を重視した法面緑化基盤を必要とする場合、保水力の高い中粒部主体の炭化物を配合する。他方、化学肥料の使用量軽減を図りたい場合には、ミネラル補給効果が高い細粒部、極細粒部主体の木炭の粒径組成とし、保水性についてはパーライトや高分子吸水材等の混合で補うのがよい。
【００２９】
このように緑化すべき斜面の条件や目的に応じ、木炭など植物性炭化物を効果的に使用することができる。
【００３０】
これまで述べてきた植物性炭化物の保水力向上やミネラルの補給効果の他にも、植物性炭化物を法面緑化基盤材に配合すれば、基盤材乾燥時の水浸透性を向上させ得ることを実験により確認した。以下にその実験の内容を示す。
【００３１】
なお、この実験例では、植物性炭化物の典型例である木炭を利用するが、同様な効果を木炭以外の植物性炭化物によっても得ることができる。
【００３２】
［実験例］
図１（Ａ）、（Ｂ）に示すように、供試基盤材１を流し台10上に傾斜させて置き、支持台12上の医療用の点滴装置14を用いて、乾燥した供試基盤材１に水を与え、木炭の混合による水浸透性の変化を測定した。
【００３３】
実験条件

の３試験区を設定し、各試験区について供試基盤材１を各１枚、計３枚作成し、ガラス温室内で１月程度乾燥した。
▲４▼降水方法：医療用の点滴装置14を用い、供試基盤材１に散水した（図１（Ａ）参照）。降水量は約20mm／hr程度であった。図１における供試基盤材１上の黒い部分３は、点滴装置14からの降水が供試基盤材１の上を流れた形跡即ち流水跡を示す。
▲５▼測定方法：降水開始から５分後、10分後、20分後、30分後の各降水時問経過後に、供試基盤材１の重量を速やかに測定した。
▲６▼その他：供試基盤材１を傾斜角度α＝45度（図１（Ｂ）参照）で設置した。試験は、各試験区とも２回反復実施した。
【００３４】
試験結果
測定結果を図２、３及び４に示す。
図２のカーブ20A、20B及び20Cは、供試基盤材１の試験区1A、1B、及び1Cの保持水量の経時的変化を夫々表す。
図３のカーブ30A、30B及び30Cは、供試基盤材１の試験区1A、1B、及び1Cからの流出水の積算量の経時的変化を夫々表す。
図４のカーブ40A、40B及び40Cは、供試基盤材１の試験区1A、1B、及び1Cの基盤重量の経時的変化を夫々表す。
【００３５】
これらのカーブから次のことが認められる。
（ａ）時間の経過と共に供試基盤材１に水分が浸透していくが、やがて底面から流出水が出るのを確認できた。
（ｂ）図２に供試基盤材１に保持された水分量の変化を示すが、木炭を添加しない場合に比べ、木炭を添加した場合の方が水分増加量が大きくなる傾向が認められた。
（ｃ）図３に流出水の積算量の変化を示すが、木炭の無い場合の方が大きくなる傾向が認められた。つまり、木炭を添加した供試基盤材１の方が、水をより多く浸透させ且つ供試基盤材１内に水をより多く保持させていたことがわかる。
（ｄ）図４のカーブは、図２と同様な傾向を示す。
【００３６】
以上の実験結果に示されるように、木炭を配合することにより法面緑化基盤材の水の浸透性、保水性を向上させ得ることが確認された。
【００３７】
【発明の効果】
以上詳細に説明したように、本発明の法面緑化基盤材は、粒度に応じて異なる栄養分補給・保水・水浸透等の能力が備わった植物性炭化物を、天然及び／又は人工土壌に適宜に添加したものであるので、次のような効果を奏する。
【００３８】
（イ）法面緑化基盤材の保水力を高め、法面緑化の確実化を図ることができる。
（ロ）法面緑化基盤材の保肥性又はミネラル補給能力を高め、法面緑化の効率を向上させることができる。
（ハ）法面緑化基盤材の水浸透性を改良し、種子の発芽及び植物の初期成長を確保することができる。
（ニ）緑化すべき法面の条件に応じ植物性炭化物の粒度分布を適当に選択し、環境に適した法面緑化を実施することが可能となる。
（ホ）間伐材の有効活用を図ることができる。
【図面の簡単な説明】
【図１】は、法面緑化基盤材の保水力を測定する装置の一例の説明図である。
【図２】は、図１の基盤材における保持水量の経時変化を示すグラフである。
【図３】は、前記基盤材の流出水の積算量の経時変化を示すグラフである。
【図４】は、前記基盤材の重量の経時変化を示すグラフである。
【図５】は、粒径の異なる木炭の保水力測定値の一例を示す図である。
【符号の説明】
１…法面緑化基盤材３…流水跡
10…流し台 12…支持台
14…点滴装置[0001]
[Field of the Invention]
The present invention relates to a planting base material and planting method using plant carbides, and in particular, used for planting slopes (sometimes referred to as “slopes”) generated during civil works such as site preparation. Related to greening base materials. Here, the vegetable carbide is obtained by carbonizing a plant material such as wood, bamboo, or rice husk, and is typically charcoal.
[0002]
In the present invention, unused agricultural and forest resources such as thinned timber and rice husks are heated and carbonized to form charcoal or husk charcoal, and then used as a greening base material for the purpose of effective utilization of these unused resources. Can also be provided.
[0003]
[Prior art]
Artificial slopes created by embankment or ground cutting are called slopes (Shinji Kobashi et al., “Cutting edge greening”, Soft Science Co., Ltd., 1995, page 2). Bare slopes are prone to water flow and dangerous slope substrate collapses, so rapid stabilization measures must be taken for bare slopes, and therefore greening work, ie plant cover Construction to apply is necessary.
[0004]
Slope revegetation work is carried out by seedling installers who plant seedlings that have been separately grown on the slopes, or by seeders who sow plant seeds on the slopes. In an example of a seedling installation work, after fixing a root pot of a seedling of a woody plant to a slope, a base consisting of a greening base material made of natural soil and / or artificial soil and a seed, fertilizer, bonding material, etc. of a herbaceous plant. The material is applied to the entire surface of the slope, and the slope is covered with both woody plants and herbaceous plants. In an example of the sowing plant, a material made by packing a planting base material made of peat moss artificial soil and herbaceous plant seeds into a water-soluble polyvinyl alcohol bag is installed on the entire slope, The slope is covered with germinated and grown herbaceous plants.
[0005]
In these examples of slope planting work, a greening base material made of natural soil and / or artificial soil is used in both the seedling installation work and the sowing work.
[0006]
By the way, in the field of agriculture, charcoal is designated as a soil conditioner mainly intended to improve water permeability, based on the method of promoting geopower. Other effects of charcoal have been confirmed by previous research studies, including water retention improvement effects, mineral replenishment effects, and microbial habitats.
[0007]
In the case of slope planting, there are some examples that have verified the application effect when charcoal is mixed with the base material mainly made of bark compost etc. (Research Association for Multipurpose Utilization Technology of Wood Carbonization Component, 1994). According to the report, depending on the type and conditions of the greening plant, there is an application effect. However, there are few examples that have been verified yet, and no verification examples based on differences in charcoal characteristics due to differences in the particle size of charcoal focused in the present invention are found.
[0008]
In this way, when charcoal is conventionally used as a material for improving the South Korea, it is important to note the difference in charcoal properties due to the difference in charcoal particle size and particle size composition, and the difference in soil improvement effect exhibited. Use charcoal with various and non-uniform particle size composition, from large to powdery, due to manufacturing and construction reasons, or sifted to match experimental conditions I stayed.
[0009]
[Problems to be solved by the invention]
The slope greening base material mainly composed of bark compost has a problem that it tends to become water-repellent as the base surface dries if there is no rain for several days after spraying. It is known that the base material in such a state causes a decrease in the permeability of rainwater during rainfall. One to four weeks after the construction is a period of germination and initial growth of seeds mixed in the base material, and the moisture condition at this time has a great influence on the formation of the vegetation. Conventionally, the base material in such a state has been subjected to measures such as drilling a hole by some method and creating a space for rainwater to enter, but such a measure has the problem of being troublesome and time-consuming. is there.
[0010]
Therefore, there is a demand for materials that have the effect of improving the permeability of rainwater and that are inexpensive and harmonized with the ecosystem.
[0011]
In addition, from the viewpoint of landscape and ecosystem harmony, there is a growing need for greening of slopes with severe environmental conditions such as rock slopes and mortar spray slopes. Moisture conditions are a major factor in the establishment of such greening. Various polymeric water-absorbing polymers have been developed and commercialized in order to increase the water retention of the greening base material, but these are expensive and there is a need for cheaper materials.
[0012]
Charcoal is a typical vegetable carbide. There are various raw materials for charcoal, but the effective use of thinned wood in mountainous areas as charcoal is expected as an effective and advanced use of resources and also in the activation of mountainous areas. .
[0013]
Effective use of charcoal obtained from thinned wood as part of the base material for slope revegetation means that surplus resources generated in the process of cultivating timber resources in mountainous areas can be used for the creation of new greenery through tree planting. Since it is used effectively, it can be said that it is a very rational usage method in terms of resource recycling. In addition, it can be said that the materials are in harmony with the natural ecosystem.
[0014]
However, when plant charcoal such as charcoal is used as a base material for slope planting, simply mixing it with the base material will not be able to fully utilize the soil improvement effect of charcoal, and further expansion / spreading of its use cannot be expected. . Therefore, it is necessary to clarify the application effect of plant carbides such as charcoal, and to develop more advanced usage methods to promote effective utilization of plant carbides.
[0015]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present inventor has repeated experimental research, paying attention to the fact that charcoal grains having different particle sizes exhibit different soil improving material effects when charcoal is used as a soil improving material. As a result, we obtained knowledge about the relationship between the particle size of plant charcoal such as charcoal and soil improvement performance, and succeeded in providing a high quality slope planting base material by using the knowledge.
[0016]
FIG. 5 shows data obtained by measuring the water retention ability of charcoal having different particle diameters with respect to the water retention improvement effect by the granular plant carbide. According to the figure, compared with fine particles with a particle size of less than 4 mm, coarse particles with a particle size of 7 mm or more have a water retention capacity of about 46% (4.7 / 3.2), which is medium with a particle size of 4-7 mm. It can be seen that the water retention capacity is about 65% higher (5.3 / 3.2). This is considered to be related to the fact that the fine charcoal peculiar to charcoal is remarkably formed in large charcoal fragments larger than medium grains compared with fine powdery charcoal.
[0017]
Next, Table 1 shows the results of measurement and comparison of differences in soil chemical characteristics due to differences in the particle size of charcoal. According to the table, it can be seen that ultrafine charcoal having a particle size of 2 mm or less contains more plant nutrients than charcoal having a relatively coarse particle size of 2 to 4 mm. In other words, compared to relatively coarse charcoal, ultrafine charcoal contains about 60% more exchangeable calcium, about twice the exchangeable magnesium, and about 40% more exchangeable potassium. It contains a lot of important cations as nutrients. This is a portion corresponding to the mineral replenishment effect generally referred to, but it can be seen that, in terms of this mineral replenishment ability, ultrafine charcoal is more effective than relatively coarse charcoal.
[0018]
[Table 1]

[0019]
Thus, the soil improvement characteristic which the charcoal possesses changes with particle sizes of charcoal. That is, the fine-grained portion has a higher ability to supply nutrients and minerals such as calcium, potassium, and phosphoric acid, and the middle-grained portion tends to have higher water retention and fertilizer. This tendency is also presumed to be the same for plant carbides such as bamboo, grass charcoal, and rice husk charcoal other than charcoal.
[0020]
Therefore, various soil improvement effects by plant carbides are more effectively exhibited by arbitrarily blending the particle size composition of carbides according to the environmental conditions of the place to be planted and the conditions such as target vegetation. Will lead to being.
[0021]
The planting base material using plant carbide according to the present invention comprises 70-98% by volume soil material with or without the addition of peat moss, bark compost, or coconut shell to natural and / or artificial soil, and a particle size of 5 It consists of 2-30% by volume of granular vegetable carbide containing a fine grain part of less than mm and a medium grain part having a particle size of 5 mm or more in a proportion according to the soil physicochemical improvement characteristics .
[0022]
Preferably, the above-mentioned plant carbide has an ultrafine particle portion with a particle size of less than 2 mm and a fine particle portion with a particle size of 2 mm or more and less than 5 mm and a particle size of 5 mm or more and less than 10 mm with high water retention and fertilizer. Include the grain part and the coarse grain part with a grain size of 10 mm or more and within the limit of formation of the slope greening base material in a proportion according to the soil physicochemical improvement characteristics of the application.
[0023]
In addition, the slope greening base material is a material used as an anti-erosion material (agent), for example, a curing material such as wood fiber, a curing material such as an asphalt emulsion, an adhesive such as a polyvinyl acetate solution, and the like. One or more additives selected from the group consisting of a bonding agent such as cement, and a water retention material such as pearlite and a polymer water-absorbing material can be added.
[0024]
The planting method using plant carbide according to the present invention covers the slope of the ground with a planting base material that does not contain or includes the above-mentioned additives, and uses the planting base material on the slope. It is made by growing plants.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
The blending amount of actual plant charcoal such as charcoal with respect to the entire greening base material should be selected from 2% by volume to 30% by volume at most. The appropriate amount of plant carbide is carefully selected according to various natural and cost conditions at the place where the greening base material is actually installed.
[0026]
Moreover, the soil physicochemical improvement characteristics such as the water retention ability and mineral replenishment ability of the plant carbide continuously change according to the difference in the particle size of the carbide. The above data were obtained experimentally for typical parts of fine and medium grain parts of vegetable carbide. For the convenience of the present invention, the grain size of the plant carbide is a coarse grain part having a grain size of 10 mm or more and less than the limit for forming a slope greening base material, a medium grain part having a grain size of 5 to 10 mm, and a grain size. 5 to 2 mm is referred to as a fine-grained portion, and those having a particle size of less than 2 mm are referred to as ultrafine-grained portions.
[0027]
In a preferred embodiment, the amount of plant carbide is 10% by volume relative to the entire slope greening base material, and the type and size distribution of plant carbide is 5% of the 10%. By using fine-grained charcoal with a diameter of 5 mm or less and the remaining 5% of charcoal with a grain size of 5 mm or more, a sloped greening substrate material that balances the mineral replenishment effect and the water retention effect is obtained.
[0028]
When the water condition in the place to be planted is poor and a slope planting base that emphasizes water retention is required, a medium-grain-part-based carbide with high water retention is blended. On the other hand, if you want to reduce the amount of chemical fertilizer used, use a fine particle part with a high mineral replenishment effect, the particle size composition of charcoal mainly composed of fine particle part, and water retention by mixing with pearlite or polymer water absorbent It is good to supplement.
[0029]
In this way, plant carbides such as charcoal can be effectively used according to the conditions and purpose of the slope to be greened.
[0030]
In addition to improving the water retention capacity of plant carbides and mineral replenishment effects described so far, it is possible to improve water permeability when drying the base material by adding plant carbide to the slope greening base material. Confirmed by experiment. The contents of the experiment are shown below.
[0031]
In this experimental example, charcoal, which is a typical example of plant carbide, is used, but the same effect can be obtained with plant carbide other than charcoal.
[0032]
[Experimental example]
As shown in FIGS. 1 (A) and 1 (B), the test base material 1 is placed on the sink 10 in an inclined manner, and dried using the medical drip device 14 on the support base 12. Water was given to No. 1 and the change in water permeability due to mixing of charcoal was measured.
[0033]
Experimental conditions

No. 3 test zones were set, one test base material 1 was prepared for each test zone, 3 in total, and dried in a glass greenhouse for about one month.
{Circle around (4)} Precipitation method: Using a medical drip device 14, water was sprayed on the test base material 1 (see FIG. 1 (A)). Precipitation was about 20 mm / hr. A black portion 3 on the test base material 1 in FIG. 1 shows a trace of the precipitation from the drip device 14 flowing over the test base material 1, that is, a running water trace.
(5) Measurement method: The weight of the test base material 1 was promptly measured after 5 minutes, 10 minutes, 20 minutes and 30 minutes after the start of precipitation.
(6) Others: The test base material 1 was installed at an inclination angle α = 45 degrees (see FIG. 1 (B)). The test was repeated twice for each test group.
[0034]
Test results The measurement results are shown in Figs.

Curves

20A, 20B, and 20C in FIG. 2 represent changes over time in the amount of water retained in the

test sections

1A, 1B, and 1C of the test base material 1, respectively.

Curves

30A, 30B, and 30C in FIG. 3 represent changes over time in the accumulated amount of effluent from the

test sections

1A, 1B, and 1C of the test base material 1, respectively.
Curves 40A, 40B, and 40C in FIG. 4 represent changes over time in the base weights of the

test sections

1A, 1B, and 1C of the test base material 1, respectively.
[0035]
From these curves, the following can be observed.
(A) Although moisture permeates into the test base material 1 with the passage of time, it was confirmed that effluent water came out from the bottom.
(B) Although the change of the water | moisture content hold | maintained at the test base material 1 is shown in FIG. 2, compared with the case where charcoal is not added, the direction in which the amount of water | moisture increases is recognized when charcoal is added. .
(C) FIG. 3 shows the change in the accumulated amount of effluent water, but a tendency to increase in the absence of charcoal was recognized. That is, it can be seen that the test base material 1 to which charcoal was added permeated more water and retained more water in the test base material 1.
(D) The curve in FIG. 4 shows the same tendency as in FIG.
[0036]
As shown in the above experimental results, it was confirmed that the water permeability and water retention of the slope greening base material can be improved by adding charcoal.
[0037]
【The invention's effect】
As described above in detail, the slope planting base material of the present invention is suitable for natural and / or artificial soil by using plant carbides having different nutrient supply, water retention, water penetration, etc., depending on the particle size. Since it has been added, the following effects are obtained.
[0038]
(B) The water retention capacity of the slope greening base material can be increased to ensure the slope greening.
(B) It is possible to increase the fertilizing ability or mineral replenishment ability of the slope greening base material and improve the efficiency of slope greening.
(C) The water permeability of the slope greening base material can be improved, and seed germination and initial plant growth can be ensured.
(D) It is possible to appropriately select the particle size distribution of the plant carbide according to the conditions of the slope to be greened, and to implement the slope greening suitable for the environment.
(E) Effective utilization of thinned wood can be achieved.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of an example of an apparatus for measuring the water retention capacity of a slope greening base material.
FIG. 2 is a graph showing the change over time in the amount of retained water in the base material of FIG. 1;
FIG. 3 is a graph showing a change with time of an integrated amount of outflow water of the base material.
FIG. 4 is a graph showing the change over time of the weight of the base material.
FIG. 5 is a diagram showing an example of measured water retention values of charcoal having different particle sizes.
[Explanation of symbols]
1 ... Slope greening base material 3 ... Traffic water trace
10 ... sink 12 ... support stand
14 ... Drip device

Claims

Peat moss in natural and / or artificial soil, bark compost, or a soil material 70-98 volume% not selectively added or added coconut husk, particle size 5 mm less than the fine grain portion and a particle size more than 5 mm of Chutsubu A planting base material for planting green using 2 to 30% by volume of granular plant carbide that is contained in a proportion according to soil physicochemical improvement characteristics .

The greening base material according to claim 1, wherein the plant carbide has an extremely fine grain part having a particle size of less than 2 mm and a fine grain part having a particle size of 2 mm or more and less than 5 mm, and a particle size having a high water retention and fertilizing ability. Plant nature including medium grain part of 5mm or more and less than 10mm and coarse grain part within grain size of 10mm or more and within the limit of formation of slope greening base material in proportion according to required soil physicochemical improvement characteristics Slope greening base material using carbide.

The greening base material according to claim 1 or 2, wherein the plant carbide is used as a charcoal, and the plant carbide is used as charcoal.

The greening base material according to any one of claims 1 to 3, comprising 10% by volume of the plant carbide and 90% by volume of the soil material , and the plant carbide includes a half amount of granular charcoal having a particle size of less than 5 mm and the remaining half amount. Slope greening base material using plant carbide, including granular charcoal with a particle size of 5mm or more.

The planted base material according to any one of claims 1 to 4, wherein one or more additives selected from the group consisting of a curing material, a curing agent, an adhesive, a bonding agent , and a water retention material are added to the soil material. Slope greening base material using carbonized carbide.

The planting base material according to any one of claims 1 to 5, wherein the granular plant carbide is obtained by subjecting the wood, bamboo, or rice husk carbide to a desired granulation process. Greening base material.

A slope revegetation method using plant carbide obtained by covering the slope of the ground with the greening base material according to any one of claims 1 to 6 and growing a plant on the slope using the greening base material.