JP2004269651A - SOIL CONDITIONER AND METHOD FOR IMPROVING SOIL pH USING THE SAME - Google Patents
SOIL CONDITIONER AND METHOD FOR IMPROVING SOIL pH USING THE SAME Download PDFInfo
- Publication number
- JP2004269651A JP2004269651A JP2003061202A JP2003061202A JP2004269651A JP 2004269651 A JP2004269651 A JP 2004269651A JP 2003061202 A JP2003061202 A JP 2003061202A JP 2003061202 A JP2003061202 A JP 2003061202A JP 2004269651 A JP2004269651 A JP 2004269651A
- Authority
- JP
- Japan
- Prior art keywords
- soil
- sulfur
- oxidizing bacteria
- improving
- alkaline
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Micro-Organisms Or Cultivation Processes Thereof (AREA)
- Soil Conditioners And Soil-Stabilizing Materials (AREA)
Abstract
Description
【０００１】
【発明の属する技術分野】
本発明は、土壌改良材及びそれを用いた土壌ｐＨの改良方法に関する。さらに詳しくは、本発明は、硫黄と、特定の窒素含有量を有する有機物、あるいはさらに、ある種の硫黄酸化細菌を含み、アルカリ性土壌、特に強アルカリ性土壌のｐＨを、植物の生育に適したｐＨに効果的に低下させ得る、取り扱いやすく、低コストの土壌改良材、及び該土壌改良材を用いて、アルカリ性土壌、特に強アルカリ性土壌のｐＨを効率よく低下させる土壌ｐＨの改良方法に関するものである。
【０００２】
【従来の技術】
地球上には広くアルカリ性土壌が分布しており、特に乾燥地帯では、塩類集積に起因してアルカリ性化が助長される傾向にある。土壌のアルカリ性化が進行するとリンや微量成分などが不溶化し、植物の成長が抑制される。そのため、ほとんどの植物においては、その適性ｐＨ領域は微〜弱酸性（微酸性ないし弱酸性）であることが知られている。したがって、強アルカリ性土壌を適切に改良し、微〜弱酸性化できれば、乾燥地帯を含め多くの土壌において、植物の成長促進を図ることが可能となる。
ところで、硫黄と硫黄酸化細菌を用いて土壌ｐＨを低下させる方法は、１９６０年代から知られている（例えば、特許文献１参照）。しかしながら、この方法においては、硫黄は危険物であるため、一般の作業者が取り扱うには問題があると共に、単純に両者を添加したのみでは、硫黄酸化細菌が活動し始めるまでに長時間を要するという問題があった。また、硫黄の代わりに硫化第一鉄が良く使用されるが、このものは、ｐＨ低下能に劣るという欠点があった。
【０００３】
そこで、このような問題に対処するために、幾つかの土壌改良材料が提案されている。例えば（１）有機酸と硫黄からなるｐＨ降下促進剤（例えば文献２参照）、（２）硫黄でセラミックスをコーティングした土壌改良材（例えば、特許文献３参照）、（３）浄水場発生土に硫黄を添加した芝の目土（例えば、特許文献４参照）、（４）硫黄と腐植酸からなる土壌改良材（例えば、特許文献５参照）、（５）硫黄と酸性炭化物からなる中和剤（例えば、特許文献６参照）、（６）硫黄酸化菌培養物と硫黄末からなる土壌改良組成物（例えば、特許文献７参照）などが提案されている。
しかしながら、これらの土壌改良材料は、いずれも以下に示すような問題を有し、必ずしも十分に満足し得るものではなかった。
【０００４】
すなわち、前記（１）のｐＨ降下促進剤においては、有機酸が土壌中の病原菌の活動も活性化し、作物に悪影響を及ぼす可能性がある上、硫黄酸化細菌の活動は、酸性領域で活発化する傾向が強く、土壌がアルカリ性の場合には，効果が発揮されにくいなどの問題がある。また、前記（２）の土壌改良材は、硫黄酸化細菌が活発化するまでに長時間を要するし、前記（３）の芝の目土においては、実施例では、酸性〜中性の土壌しか示されておらず、上述の（１）と同様の問題がある。
前記（４）の土壌改良材においては、対照区のｐＨ低下結果が示されておらず、それ自体が酸性である腐植酸のみを混入しただけでもｐＨが低下することから、硫黄との混合効果が明確ではない。また、前記（５）の中和剤においては、酸性炭化物は多孔質炭化物に硫酸を吸着させたものであり、したがって、事前に酸性炭化物を調製するためにコストが高くつくのを免れない。また、酸性炭化物自体のｐＨが強酸性であるため、作業者の安全上、素手での取扱いが困難である。なお、この特許文献６には、酸性炭化物処理により、土壌のアルカリ性が低下することによって硫黄酸化細菌が活動を活発化したことが述べられている。
前記（６）の土壌改良組成物は、硫黄酸化細菌を動物性有機物、植物性有機物及び無機資材を原料とする培養物で増殖させたのち、硫黄と混合した組成物であり、したがって、事前に硫黄酸化細菌を資材中で培養する必要があり、操作が煩雑である上、培養に４０日間以上を要し、コストが高くつくのを免れない。
【０００５】
【特許文献１】
米国特許第３，１８６，８２６号明細書
【特許文献２】
特開平８−１５７８２２号公報
【特許文献３】
特開２０００−３０３０６８号公報
【特許文献４】
特開２００１−３２０９５５号公報
【特許文献５】
特開２００１−３４８５７３号公報
【特許文献６】
特開２００２−１３８２８０号公報
【特許文献７】
特開平１１−３０２６４９号公報
【０００６】
【発明が解決しようとする課題】
本発明は、このような状況下で、アルカリ性土壌、特に強アルカリ性土壌のｐＨを、植物の生育に適したｐＨに効果的に低下させることができ、かつ植物の生育に悪影響を及ぼすことがない上、取り扱いが容易であって、コストの低い経済的に有利な土壌改良材、及び該土壌改良材を用いて、アルカリ性土壌、特に強アルカリ性土壌のｐＨを、植物の生育に適したｐＨに効率よく低下させる土壌ｐＨの改良方法を提供するものである。
【０００７】
【課題を解決するための手段】
本発明者らは、前記目的を達成するために鋭意研究を重ねた結果、硫黄と、特定の窒素含有量を有する有機物、あるいはさらに、ある種の硫黄酸化細菌を含む土壌改良材により、その目的を達成し得ることを見出した。本発明は、かかる知見に基づいて完成したものである。
すなわち、本発明は
（１）（Ａ）硫黄及び／又は硫黄化合物と、（Ｂ）窒素含有量が１質量％以上で、かつ総窒素量に占める有機態窒素含有量が２０質量％以上である有機物を含むことを特徴とする土壌改良材（以下、土壌改良材Ｉと称す。）、
（２）さらに、（Ｃ）ｐＨ７．５以上のアルカリ性条件下で増殖能を有する硫黄酸化細菌を含むことを特徴とする土壌改良材（以下、土壌改良材ＩＩと称す。）、（３）（Ｃ）成分として、土壌改良材が適用される土壌に生息する硫黄酸化細菌を含む上記（２）の土壌改良材、
【０００８】
（５）（Ａ）成分が硫黄単体である上記（１）〜（３）の土壌改良材、
（６）上記（１）〜（４）の土壌改良材を用いることを特徴とする土壌ｐＨの改良方法、
（６）アルカリ性土壌に、上記（１）、（４）の土壌改良材を加え、ｐＨ７．５以上のアルカリ性条件下で増殖能を有する土着の硫黄酸化細菌を活性化させてｐＨを低下させ、次いで他の土着の硫黄酸化細菌を活性化させる上記（５）の土壌ｐＨの改良方法、及び
（７）アルカリ性土壌に上記（２）〜（４）の土壌改良材を加え、（Ｃ）成分の硫黄酸化細菌の作用によりｐＨを低下させ、次いで土着の硫黄酸化細菌を活性化させる上記（５）の土壌ｐＨの改良方法、
を提供するものである。
【０００９】
【発明の実施の形態】
本発明の土壌改良材においては、２つの態様、すなわち土壌改良材Ｉおよび土壌改良材ＩＩがある。
土壌には一般に多数の硫黄酸化細菌が存在しており、硫黄を土壌に投入すると、土着の硫黄酸化細菌が硫黄を酸化して硫酸を生産するため、土壌の酸性化が進む。しかしながら、ほとんどの硫黄酸化細菌は、酸性条件下のみで活発化すると考えられており、ｐＨ７．０以上のアルカリ性土壌に単に硫黄を添加しても、その効果はほとんど発揮されない。したがって、アルカリ性土壌のｐＨを、硫黄を用いて改良するためには、これまで、酸性度の高い資材と併用し、土壌全体又は一部を酸性にする技術が提案されてきた。
【００１０】
本発明の土壌改良材Ｉは、（Ａ）硫黄及び／又は硫黄化合物と、（Ｂ）特定の窒素含有量を有する有機物を含むものであって、アルカリ性土壌のｐＨを低下させる機能を有している。そのメカニズムは、該土壌改良材Ｉが土壌中に存在する硫黄酸化細菌のうち、ｐＨ７．５以上のアルカリ性条件下でも活動し得る種類の細菌を活発化することにより、土壌ｐＨが低下し、その後、他の通常の硫黄酸化細菌が働いたためと考えられる。
一方、本発明の土壌改良材ＩＩは、（Ａ）成分、（Ｂ）成分に加えて、（Ｃ）ｐＨ７．５以上のアルカリ性条件下で増殖能を有する硫黄酸化細菌を含むものであって、強アルカリ性土壌に加えると、該（Ｃ）成分の細菌の作用により、土壌のｐＨが通常の硫黄酸化細菌が活動を開始するｐＨまで低下し、土着硫黄酸化細菌を活性化させる機能を有している。
【００１１】
次に、前記の土壌改良材Ｉ及び土壌改良材ＩＩについて説明する。
土壌改良材Ｉ及びＩＩにおいては、（Ａ）成分として硫黄や硫黄化合物が用いられる。硫黄の種類やその由来については、特に制限はなく、硫黄鉱床から得られるもの、石油や天然ガスの脱硫工程、廃液などから回収される硫黄などを用いることができる。また、硫黄の純度についても特に制限はないが、効果の点から、純度は高い方が好ましい。一方、硫黄化合物としては、例えば石膏やパイライトなどが挙げられる。
本発明においては、該（Ａ）成分として、硫黄や硫黄化合物を一種用いてもよく、二種以上組み合わせて用いてもよいが、効果の点や余剰硫黄の有効利用の点から、特に硫黄単体を用いることが好ましい。
本発明の土壌改良材Ｉ及びＩＩにおいて、（Ｂ）成分として用いられる有機物は、窒素含有量が１質量％以上、好ましくは１．５質量％以上で、かつ総窒素量に占める有機態窒素含有量が２０質量％以上、好ましくは２２質量％以上のものである。このような有機物は、土壌に加えられると、土着の硫黄酸化細菌のうち、ｐＨ７．５以上、好ましくは８．０〜１０のアルカリ性条件下でも活動し得る種類の細菌を活発化する作用を有している。
【００１２】
このような（Ｂ）成分の有機物としては、例えば活性汚泥、微生物培養物及びその残渣、動物性、植物性有機物からなる生ゴミやその他堆肥などが挙げられる。これらは一種を用いてもよく、二種以上を組み合わせて用いてもよい。
また、この（Ｂ）成分の有機物は、前記（Ａ）成分と併用することにより、該（Ａ）成分が危険物である硫黄単体であっても、その取り扱いを容易にし、安全化を図ることができる。
本発明の土壌改良材Ｉ及びＩＩにおける前記（Ａ）成分と（Ｂ）成分との含有割合は、（Ａ）成分の硫黄換算量と（Ｂ）成分の有機物量との質量比が１０：９０ないし９０：１０の範囲になるように選定することが好ましい。
さらに、取り扱いを容易にするために、両成分を粒状化する方法をとることができる。この場合に、成形性を高めるためにアラビアガムのような多糖類、ポリビニルアルコールのような粘性物、ベントナイトなどをバインダーとして使用できる。
【００１３】
本発明の土壌改良材ＩＩにおいて、（Ｃ）成分として用いられる硫黄酸化細菌は、ｐＨ７．５以上、好ましくは８．０〜１０のアルカリ性条件下でも増殖能を有する細菌である。このような硫黄酸化細菌の菌種については特に制限はなく、例えばチオバシラス・アクアエスリス（Ｔｈｉｏｂａｃｉｌｌｕｓ ａｑｕａｅｓｕｌｉｓ）、チオバシラス・サーモスルファタス（Ｔｈｉｏｂａｃｉｌｌｕｓ ｔｈｅｒｍｏｓｕｌｆａｔｕｓ）、チオバシラス・シアシリス（Ｔｈｉｏｂａｃｉｌｌｕｓ ｔｈｙａｓｉｒｉｓ）、チオバシラス・ベルスタス（Ｔｈｉｏｂａｃｉｌｌｕｓ ｖｅｒｓｕｔｕｓ）などが知られている。これらの硫黄酸化細菌は一種を用いてもよく、二種以上を組み合わせて用いてもよい。
（Ｃ）成分の硫黄酸化細菌の菌数は、土壌改良材ＩＩの土壌への投入量にもよるが、土壌改良材ＩＩ１ｇ当たり、通常１×１０３ｃｆｕ以上、好ましくは１×１０５ｃｆｕ程度である。
【００１４】
本発明の土壌改良材ＩＩにおいては、前記（Ｃ）成分として、土壌改良材が適用される土壌（被処理土壌）に生息する硫黄酸化細菌を含むことが好ましい。
土壌に生息する硫黄酸化細菌は、その土壌環境に適応していると考えられる。その土着菌を土壌と共に土壌改良材ＩＩに加えてもよいが、より効率を高めるには、事前に菌密度を高めておく方が望ましい。菌密度向上法としては、一般に用いられる硫黄酸化細菌の液体培地に、被処理土壌から単離した硫黄酸化細菌を添加して培養したり、あるいは被処理土壌ごと該培地に添加して培養する方法などが挙げられる。硫黄酸化細菌用液体培地としては、例えば改変スターキー（Ｓｔａｒｋｅｙ）培地などを挙げることができる。
本発明の土壌改良材は、圧縮造粒機などで直径１〜１０ｍｍ程度に造粒して用いることが、取り扱い上有利である。
【００１５】
本発明の土壌ｐＨの改良方法は、前述の土壌改良材Ｉ又は土壌改良材ＩＩを用いて土壌ｐＨを改良する方法であって、アルカリ性土壌、特に強アルカリ性であるｐＨ８．５以上の土壌を、植物の生育に適したｐＨ５．５〜６．５程度まで低下させる。
この土壌ｐＨの改良方法においては、２つの態様、すなわち、（１）アルカリ性土壌、例えば強アルカリ性であるｐＨ８．５以上のアルカリ性土壌に、前述の土壌改良材Ｉを加え、ｐＨ７．５以上、好ましくは８．０〜１０のアルカリ性条件下で増殖能を有する土着の硫黄酸化細菌を活性化させてｐＨを低下させ、次いで他の土着の通常の硫黄酸化細菌を活性化させて、土壌のｐＨを植物の生育に適したｐＨ、（例えばｐＨ５．５〜６．５程度）に改良する方法、及び（２）アルカリ性土壌、例えば強アルカリ性であるｐＨ８．５以上のアルカリ性土壌に、前述の土壌改良材ＩＩを加え、（Ｃ）成分であるｐＨ７．５以上、好ましくは８．０〜１０のアルカリ性条件下で増殖能を有する硫黄酸化細菌の作用によりｐＨを低下させ，次いで土着のｐＨを植物の生育に適したｐＨ、例えばｐＨ５．５〜６．５程度に改良する方法、がある。
前記（１）及び（２）の土壌ｐＨの改良方法においては、それぞれ土壌改良材Ｉ及びＩＩの投入量は、通常０．１〜１０ｋｇ／ｍ２、好ましくは０．３〜７ｋｇ／ｍ２の範囲で選定される。なお、この場合、少なくとも深さ１０ｃｍは耕起することが好ましい（耕起深度を浅くする場合には、それに伴い投入量を低減する）。投入及び混合方法については特に制限はなく、通常の栽培時における耕起及び処理方法で行えばよい。また、微生物の活動には水が不可欠であるため、土壌改良材投入後には、できるだけ早く土壌に散水することが望ましい。
【００１６】
【実施例】
次に、本発明を実施例により、さらに詳細に説明するが、本発明は、これらの例によってなんら限定されるものではない。
実施例１
（１）土壌改良材Ｉ−１の作製
製油所の脱硫工程で得られた粒状硫黄、及び下水処理場から得られた乾燥余剰汚泥（窒素含有量３．１質量％、総窒素量に占める有機態窒素含有量２８質量％）を、それぞれハンマーミルにて粉砕し、質量比２：８の割合で混合したのち、この混合物をロール式圧縮造粒機にて、直径が３〜５ｍｍ程度になるように成形し、土壌改良材Ｉ−１を作製した。
（２）土壌ｐＨの改良
縦１ｍ、横１ｍ、深さ０．３ｍの容器に、ｐＨが８．５〜９．０のアルカリ性土壌（砂壌土）を充填したのち、この土壌に対し、上記（１）で得た土壌改良材Ｉ−１を１．０ｋｇ／ｍ２になるように、深さ１０ｃｍ程度の範囲で混合した。次いで、これを最低温度が１５℃に設定された温室内に設置し、２日に１度の割合で十分に散水した。なお、容器の底部には水抜き穴を設け、余剰の水が流出するようにした。
土壌ｐＨの改良実験を開始してから、１、２及び３ヶ月後に土壌の一部をサンプリングし、土壌ｐＨを測定した。その結果を第１表に示す。なお、土壌の初期ｐＨは８．７であった。
【００１７】
実施例２
（１）土壌改良材Ｉ−２の作製
実施例１（１）において、硫黄と乾燥余剰汚泥との混合割合を、質量比で５：５に変更した以外は、実施例１（１）と同様にして土壌改良材Ｉ−２を作製した。
（２）土壌ｐＨの改良
実施例１（２）において、土壌改良材Ｉ−１の代わりに、上記（１）で得た土壌改良材Ｉ−２を用いた以外は、実施例１（２）と同様な操作を行った。結果を第１表に示す。
【００１８】
実施例３
（１）土壌改良材Ｉ−３の作製
実施例１（１）において、硫黄と乾燥余剰汚泥との混合割合を、質量比で８：２に変更した以外は、実施例１（１）と同様にして土壌改良材Ｉ−３を作製した。
（２）土壌ｐＨの改良
実施例１（２）において、土壌改良材Ｉ−１の代わりに、上記（１）で得た土壌改良材Ｉ−３を用いた以外は、実施例１（２）と同様な操作を行った。結果を第１表に示す。
比較例１
（１）資材Ｉ−１の作製
実施例１（１）において、乾燥余剰汚泥を用いずに、硫黄のみを用いた以外は、実施例１（１）と同様にして資材Ｉ−１を作製した。
（２）土壌ｐＨの改良
実施例１（２）において、土壌改良材Ｉ−１の代わりに、上記（１）で得た資材Ｉ−１を用いた以外は、実施例１（２）と同様な操作を行った。結果を第１表に示す。
【００１９】
比較例２
・ 資材Ｉ−２の作製
実施例１（１）において、硫黄を用いずに乾燥余剰汚泥のみを用いた以外は、実施例１（１）と同様にして資材Ｉ−２を作製した。
（２）土壌ｐＨの改良
実施例１（２）において、土壌改良材Ｉ−１の代わりに、上記（１）で得た資材Ｉ−２を用いた以外は、実施例１（２）と同様な操作を行った。結果を第１表に示す。
【００２０】
【表１】
実施例４
（１）アルカリ性硫黄酸化細菌の増殖
硫黄酸化細菌は、被処理土壌であるｐＨ８．５〜９．０のアルカリ性土壌（砂壌土）から分離したものを用いた。また、液体培地には、改変スターキー液体培地［ＦｅＳＯ４・７Ｈ２Ｏ０．０１ｇ、Ｎａ２ＭｏＯ４・２Ｈ２Ｏ０．０００７５ｇ、ＭｇＳＯ４・７Ｈ２Ｏ０．５ｇ、（ＮＨ４）２ＳＯ４２．０ｇ、ＣａＣｌ２・２Ｈ２Ｏ０．２５ｇ、ＫＨ２ＰＯ４３．０ｇ、粉末硫黄１０ｇ、蒸留水１．０リットル］をｐＨ９に調製したものを用いた。
この液体培地１００ミリリットルを５００ミリリットル容の三角フラスコに入れ、オートクレーブ滅菌（１１４℃、２０分間）したのち、無菌条件下でｐＨ８．５〜９．０のアルカリ性土壌（砂壌土）１ｇを投入した。３０℃、１５０ｒｐｍにて４週間振とう培養し、硫黄酸化細菌を増殖させた。次いで、上記と同様の組成の培地に寒天を投入し、さらにｐＨを９に調整して改変スターキー寒天培地を作製した。次に、このｐＨ９の寒天培地に、上記の硫黄酸化細菌を増殖させた液体培地の上澄み０．１ミリリットルを塗布し、３０℃で４週間培養した。得られたコロニーから無作為に３つを選び、それぞれについて新たに調製した上述の改変スターキー液体培地に再添加し、同様の条件で培養した。培養後混合して、１つのサンプルとした（以下、アルカリ性硫黄酸化細菌と称す。）。なお、このアルカリ性硫黄酸化細菌は、同定の結果、チオバシラス・サーモスルファタス（Ｔｈｉｏｂａｃｉｌｌｕｓ ｔｈｅｒｍｏｓｕｌｆａｔｕｓ）であった。
【００２２】
（２）土壌改良材ＩＩ−１の作製
製油所の脱硫工程で得られた粒状硫黄、及び下水処理場から得られた乾燥余剰汚泥（窒素含有量３．１質量％、総窒素量に占める有機態窒素含有量２８質量％）を、それぞれハンマーミルにて粉砕し、質量比５：５の割合で混合した。この混合物に、上記（１）で培養したアルカリ性硫黄酸化細菌を、得られる土壌改良材１ｇ当たり、２．０×１０４ｃｆｕになるように添加し、よく混合したのち、ロール式圧縮造粒機にて、直径が３〜５ｍｍ程度になるように成形し、土壌改良材ＩＩ−１を作製した。
（３）土壌ｐＨの改良
実施例１（２）において、土壌改良材Ｉ−１の代わりに、上記（２）で得た土壌改良材ＩＩ−１を用いた以外は、実施例１（２）と同様な操作を行った。結果を第２表に示す。
【００２３】
参考例１
（１）酸性硫黄酸化細菌の増殖
実施例４（１）において、液体培地として改変スターキー液体培地をｐＨ５に調整したものを用い、かつ寒天培地としてｐＨ５に調整した改変スターキー寒天培地を用いた以外は、実施例４（１）と同様な操作を行い、硫黄酸化細菌のサンプルを得た（以下、酸性硫黄酸化細菌と称す。）。なお、この酸性硫黄酸化細菌は、同定の結果、チオバシラス・チオオキシダンス（Ｔｈｉｏｂａｃｉｌｌｕｓ
ｔｈｉｏｏｘｉｄａｎｓ）であった。
（２）資材ＩＩ−２の作製
実施例４（２）において、アルカリ性硫黄酸化細菌の代わりに、上記（１）で得た酸性硫黄酸化細菌を用いた以外は、実施例４（２）と同様にして資材ＩＩ−２を作製した。
（３）土壌ｐＨの改良
実施例４（３）において、土壌改良材ＩＩ−１の代わりに、上記（２）で得た資材ＩＩ−２を用いた以外は、実施例４（３）と同様な操作を行った。結果を第２表に示す。
【００２４】
【表２】
【発明の効果】
本発明によれば、硫黄と、特定の窒素含有量を有する有機物、あるいはさらに、ある種の硫黄酸化細菌を含み、アルカリ性土壌、特に強アルカリ性土壌のｐＨを、植物の生育に悪影響を及ぼすことなく、植物の生育に適したｐＨに効果的に低下させ得る、取り扱いやすく、低コストの土壌改良材を提供することができる。
また、アルカリ性土壌、特に強アルカリ性土壌に前記土壌改良材を加えることにより、該土壌のｐＨを効率よく低下させ、植物の生育に適したｐＨに改良することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a soil improving material and a method for improving soil pH using the same. More specifically, the present invention comprises sulfur and organic matter with a specific nitrogen content, or even certain sulfur oxidizing bacteria, which increases the pH of alkaline soils, especially strongly alkaline soils, to a pH suitable for plant growth. The present invention relates to an easy-to-handle, low-cost soil improver that can be effectively reduced, and a soil pH improving method for efficiently reducing the pH of an alkaline soil, particularly a strongly alkaline soil, using the soil improver. .
[0002]
[Prior art]
Alkaline soils are widely distributed on the earth, and especially in arid regions, alkalinization tends to be promoted due to salt accumulation. As the soil becomes more alkaline, phosphorus and trace components are insolubilized, and the growth of plants is suppressed. Therefore, it is known that, in most plants, the appropriate pH range is slightly to weakly acidic (slightly acidic to slightly acidic). Therefore, if the strongly alkaline soil can be appropriately improved and slightly to weakly acidified, the growth of plants can be promoted in many soils including the dry zone.
By the way, a method of lowering soil pH using sulfur and sulfur-oxidizing bacteria has been known since the 1960s (for example, see Patent Document 1). However, in this method, since sulfur is a dangerous substance, there is a problem in handling by ordinary workers, and it takes a long time for the sulfur-oxidizing bacteria to start working simply by adding both. There was a problem. In addition, ferrous sulfide is often used instead of sulfur, but has a drawback that it is inferior in pH lowering ability.
[0003]
Therefore, in order to cope with such a problem, some soil improvement materials have been proposed. For example, (1) pH lowering accelerator composed of organic acid and sulfur (for example, see Document 2), (2) Soil improving material coated with ceramics by sulfur (for example, see Patent Document 3), (3) Soil generated from water purification plant Soil-added turf soil (for example, see Patent Document 4), (4) Soil improving material composed of sulfur and humic acid (for example, see Patent Document 5), (5) Neutralizing agent composed of sulfur and acidic carbide (See, for example, Patent Document 6), and (6) a soil improvement composition comprising a culture of sulfur oxidizing bacteria and sulfur powder (for example, see Patent Document 7).
However, all of these soil improvement materials have the following problems, and have not always been satisfactory.
[0004]
That is, in the pH-decreasing accelerator of the above (1), the organic acid also activates the activity of the pathogenic bacteria in the soil, which may adversely affect the crop, and the activity of the sulfur-oxidizing bacteria is activated in the acidic region. When the soil is alkaline, there is a problem that the effect is hardly exhibited. In addition, the soil improving material of the above (2) requires a long time until the sulfur oxidizing bacteria are activated, and in the grass of the above (3), only the acid-neutral soil is used in the embodiment. It is not shown and has the same problem as the above (1).
In the soil improving material (4), the results of pH reduction in the control plots are not shown, and the pH is lowered only by mixing only humic acid which is itself acidic. Is not clear. Further, in the neutralizing agent of the above (5), the acidic carbide is obtained by adsorbing sulfuric acid on the porous carbide. Therefore, it is unavoidable that the preparation of the acidic carbide in advance increases the cost. In addition, since the pH of the acidic carbide itself is strongly acidic, it is difficult to handle with bare hands in terms of worker safety. In addition, Patent Document 6 states that the sulfur-oxidizing bacteria have been activated by reducing the alkalinity of the soil due to the acid carbide treatment.
The above-mentioned soil improvement composition (6) is a composition in which sulfur-oxidizing bacteria are grown in a culture using animal organic matter, vegetable organic matter and inorganic materials as raw materials, and then mixed with sulfur. It is necessary to culture the sulfur-oxidizing bacteria in the material, the operation is complicated, and the culture requires more than 40 days, which inevitably increases the cost.
[0005]
[Patent Document 1]
US Patent No. 3,186,826 [Patent Document 2]
JP-A-8-157822 [Patent Document 3]
Japanese Patent Application Laid-Open No. 2000-303068 [Patent Document 4]
JP 2001-32095 A [Patent Document 5]
JP 2001-348573 A [Patent Document 6]
JP 2002-138280 A [Patent Document 7]
JP-A-11-302649
[Problems to be solved by the invention]
The present invention, under such circumstances, can effectively reduce the pH of alkaline soil, particularly strongly alkaline soil, to a pH suitable for plant growth, and does not adversely affect plant growth. Above, an easy-to-handle, low-cost and economically advantageous soil conditioner, and the use of the soil conditioner to reduce the pH of an alkaline soil, particularly a strongly alkaline soil, to a pH suitable for plant growth. It is intended to provide a method for improving soil pH which can be reduced well.
[0007]
[Means for Solving the Problems]
The present inventors have conducted intensive studies in order to achieve the above object, and as a result, a soil improvement material containing sulfur and an organic substance having a specific nitrogen content, or furthermore, a soil improvement material containing a certain kind of sulfur oxidizing bacteria has been developed. Was found to be achieved. The present invention has been completed based on such findings.
That is, the present invention provides (1) (A) sulfur and / or a sulfur compound, (B) a nitrogen content of 1% by mass or more, and an organic nitrogen content in a total nitrogen amount of 20% by mass or more. A soil conditioner characterized by containing organic matter (hereinafter referred to as a soil conditioner I);
(2) Furthermore, (C) a soil conditioner characterized by containing a sulfur-oxidizing bacterium capable of growing under alkaline conditions of pH 7.5 or more (hereinafter, referred to as a soil conditioner II), (3) ( C) As the component, the soil conditioner according to the above (2), which contains a sulfur-oxidizing bacterium that inhabits the soil to which the soil conditioner is applied;
[0008]
(5) The soil improving material according to (1) to (3), wherein the component (A) is sulfur alone.
(6) A method for improving soil pH, characterized by using the soil improving material of (1) to (4) above,
(6) To the alkaline soil, the soil improver of (1) or (4) is added to activate the indigenous sulfur-oxidizing bacteria capable of growing under alkaline conditions of pH 7.5 or more to lower the pH, Then, the soil pH improving method of the above (5) for activating other indigenous sulfur-oxidizing bacteria, and (7) the soil improving materials of the above (2) to (4) are added to the alkaline soil, and the component (C) (5) The method for improving soil pH according to the above (5), wherein the pH is lowered by the action of sulfur oxidizing bacteria, and then the indigenous sulfur oxidizing bacteria are activated.
Is provided.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
In the soil conditioner of the present invention, there are two embodiments, namely, a soil conditioner I and a soil conditioner II.
Generally, a large number of sulfur oxidizing bacteria are present in soil, and when sulfur is introduced into soil, indigenous sulfur oxidizing bacteria oxidize sulfur to produce sulfuric acid, so that the soil is acidified. However, most sulfur-oxidizing bacteria are considered to be activated only under acidic conditions. Even if sulfur is simply added to alkaline soil having a pH of 7.0 or more, the effect is hardly exhibited. Therefore, in order to improve the pH of an alkaline soil using sulfur, a technique has been proposed in which a soil having a high acidity is used in combination with a material having a high acidity to make the whole or a part of the soil acidic.
[0010]
The soil improving material I of the present invention contains (A) sulfur and / or a sulfur compound and (B) an organic substance having a specific nitrogen content, and has a function of lowering the pH of alkaline soil. I have. The mechanism is that the soil amendment I activates, among the sulfur-oxidizing bacteria present in the soil, those that can be activated under alkaline conditions of pH 7.5 or higher, thereby lowering the soil pH. It is thought that other normal sulfur-oxidizing bacteria worked.
On the other hand, the soil conditioner II of the present invention contains, in addition to the components (A) and (B), (C) a sulfur-oxidizing bacterium capable of growing under alkaline conditions of pH 7.5 or more, When added to a strongly alkaline soil, the action of the bacteria of the component (C) lowers the pH of the soil to a level at which normal sulfur-oxidizing bacteria start to act, and has the function of activating indigenous sulfur-oxidizing bacteria. I have.
[0011]
Next, the soil improving material I and the soil improving material II will be described.
In the soil improvement materials I and II, sulfur or a sulfur compound is used as the component (A). The type and origin of sulfur are not particularly limited, and those obtained from a sulfur deposit, sulfur recovered from a desulfurization step of petroleum or natural gas, waste liquid, and the like can be used. The purity of sulfur is not particularly limited, but the higher the purity, the better. On the other hand, examples of the sulfur compound include gypsum and pyrite.
In the present invention, as the component (A), sulfur or a sulfur compound may be used alone or in combination of two or more. However, from the viewpoint of effect and effective use of surplus sulfur, sulfur alone is particularly preferable. It is preferable to use
In the soil amendments I and II of the present invention, the organic substance used as the component (B) has a nitrogen content of 1% by mass or more, preferably 1.5% by mass or more, and contains organic nitrogen contained in the total nitrogen amount. The amount is 20% by mass or more, preferably 22% by mass or more. Such organic matter, when added to the soil, has the effect of activating a type of indigenous sulfur-oxidizing bacteria that can be activated under alkaline conditions of pH 7.5 or higher, preferably 8.0 to 10. are doing.
[0012]
Examples of such organic substances of the component (B) include activated sludge, microorganism cultures and their residues, garbage composed of animal and vegetable organic substances, and other composts. These may be used alone or in combination of two or more.
In addition, by using the organic substance (B) in combination with the component (A), even if the component (A) is a dangerous substance of simple sulfur, the handling is facilitated and safety is improved. Can be.
In the soil improvement materials I and II of the present invention, the content ratio of the component (A) and the component (B) is such that the mass ratio between the sulfur equivalent of the component (A) and the organic matter of the component (B) is 10:90. It is preferable to select the range from 90 to 90:10.
Further, in order to facilitate handling, a method of granulating both components can be employed. In this case, a polysaccharide such as gum arabic, a viscous substance such as polyvinyl alcohol, bentonite, or the like can be used as a binder to enhance moldability.
[0013]
In the soil conditioner II of the present invention, the sulfur-oxidizing bacteria used as the component (C) are bacteria having a growth ability even under alkaline conditions of pH 7.5 or more, preferably 8.0 to 10. There is no particular limitation on the species of such sulfur-oxidizing bacteria. Etc. are known. One of these sulfur-oxidizing bacteria may be used, or two or more thereof may be used in combination.
The number of the sulfur-oxidizing bacteria of the component (C) depends on the amount of the soil-improving material II added to the soil, but is usually 1 × 10 3 cfu or more, preferably about 1 × 10 5 cfu / g of the soil-improving material II. It is.
[0014]
The soil conditioner II of the present invention preferably contains, as the component (C), a sulfur oxidizing bacterium that inhabits the soil (the treated soil) to which the soil conditioner is applied.
Sulfur-oxidizing bacteria that live in soil are considered to be adapted to their soil environment. The indigenous bacteria may be added to the soil conditioner II together with the soil, but in order to increase the efficiency, it is desirable to increase the bacterial density in advance. As a method for increasing the bacterial density, a method of adding a sulfur-oxidizing bacterium isolated from a treated soil to a commonly used liquid medium of a sulfur-oxidizing bacterium and culturing it, or adding the treated soil to the medium and culturing the same. And the like. Examples of the liquid medium for sulfur-oxidizing bacteria include a modified Starkey medium.
It is advantageous in handling that the soil improving material of the present invention is granulated to a diameter of about 1 to 10 mm using a compression granulator or the like.
[0015]
The method for improving soil pH of the present invention is a method for improving soil pH using the above-mentioned soil improving material I or soil improving material II, wherein alkaline soil, particularly strongly alkaline soil having a pH of 8.5 or more, The pH is reduced to about 5.5 to 6.5 suitable for plant growth.
In this method of improving soil pH, there are two aspects, namely, (1) alkaline soil, for example, alkaline soil having a pH of 8.5 or more, which is strongly alkaline, and the above-mentioned soil improving material I is added, and the pH is preferably 7.5 or more. Activates indigenous sulfur oxidizing bacteria capable of growing under alkaline conditions of 8.0-10 to lower the pH, and then activates other indigenous normal sulfur oxidizing bacteria to raise the pH of the soil. A method of improving the pH to a level suitable for plant growth (for example, about pH 5.5 to 6.5), and (2) the above-mentioned soil improving material for alkaline soil, for example, alkaline soil of pH 8.5 or higher which is strongly alkaline. II, and the pH is lowered by the action of a sulfur-oxidizing bacterium capable of growing under alkaline conditions of pH 7.5 or more, preferably 8.0 to 10, which is the component (C). pH of the pH suitable for the growth of plants, for example, a method of improving the degree pH 5.5 to 6.5, there is.
In the soil pH improving methods (1) and (2), the input amounts of the soil improving materials I and II are usually 0.1 to 10 kg / m 2 , preferably 0.3 to 7 kg / m 2 . It is selected in the range. In this case, it is preferable to cultivate at least a depth of 10 cm (when the cultivation depth is reduced, the input amount is reduced accordingly). There is no particular limitation on the charging and mixing method, and the method may be a plowing and processing method during normal cultivation. In addition, since water is indispensable for the activity of microorganisms, it is desirable to sprinkle water on the soil as soon as possible after adding the soil conditioner.
[0016]
【Example】
Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
Example 1
(1) Preparation of soil improvement material I-1 Granular sulfur obtained in the desulfurization step of a refinery, and dry excess sludge obtained from a sewage treatment plant (nitrogen content: 3.1% by mass, organic content in total nitrogen content) (Nitrogen content: 28% by mass) is crushed by a hammer mill and mixed at a mass ratio of 2: 8, and then the mixture is rolled to have a diameter of about 3 to 5 mm by a compression granulator. To form a soil improving material I-1.
(2) Improvement of soil pH After a container of 1 m in length, 1 m in width and 0.3 m in depth is filled with alkaline soil (sand loam) having a pH of 8.5 to 9.0, the soil is subjected to the above-mentioned method ( The soil improving material I-1 obtained in 1) was mixed at a depth of about 10 cm so as to be 1.0 kg / m 2 . Next, this was placed in a greenhouse having a minimum temperature set at 15 ° C., and water was sprinkled sufficiently once every two days. A drain hole was provided at the bottom of the container to allow excess water to flow out.
One, two and three months after the start of the soil pH improvement experiment, a part of the soil was sampled and the soil pH was measured. Table 1 shows the results. The initial pH of the soil was 8.7.
[0017]
Example 2
(1) Preparation of soil improvement material I-2 Same as Example 1 (1) except that in Example 1 (1), the mixing ratio of sulfur and dry excess sludge was changed to 5: 5 by mass ratio. The soil improvement material I-2 was produced.
(2) Improvement of soil pH Example 1 (2) was the same as Example 1 (2) except that the soil conditioner I-2 obtained in (1) was used instead of the soil conditioner I-1. The same operation as described above was performed. The results are shown in Table 1.
[0018]
Example 3
(1) Preparation of soil improvement material I-3 Same as Example 1 (1) except that in Example 1 (1), the mixing ratio of sulfur and dry excess sludge was changed to 8: 2 by mass ratio. Thus, a soil improving material I-3 was produced.
(2) Improvement of soil pH Example 1 (2) was the same as Example 1 (2) except that the soil conditioner I-3 obtained in (1) was used instead of the soil conditioner I-1. The same operation as described above was performed. The results are shown in Table 1.
Comparative Example 1
(1) Preparation of Material I-1 A material I-1 was prepared in the same manner as in Example 1 (1) except that only sulfur was used without using excess dry sludge in Example 1 (1). .
(2) Improvement of soil pH In Example 1 (2), the same as Example 1 (2) except that the material I-1 obtained in the above (1) was used instead of the soil improving material I-1. Operation. The results are shown in Table 1.
[0019]
Comparative Example 2
Preparation of Material I-2 A material I-2 was prepared in the same manner as in Example 1 (1), except that only dry excess sludge was used without using sulfur in Example 1 (1).
(2) Improvement of soil pH Same as Example 1 (2) except that in Example 1 (2), the material I-2 obtained in (1) above was used instead of the soil improving material I-1. Operation. The results are shown in Table 1.
[0020]
[Table 1]
Example 4
(1) Growth of Alkaline Sulfur-Oxidizing Bacteria Sulfur-oxidizing bacteria isolated from alkaline soil (sandy loam) having a pH of 8.5 to 9.0 as a soil to be treated were used. Moreover, the liquid medium is modified Starkey liquid medium [FeSO 4 · 7H 2 O0.01g, Na 2 MoO 4 · 2H 2 O0.00075g, MgSO 4 · 7H 2 O0.5g, (NH 4) 2 SO 4 2 1.0 g, CaCl 2 .2H 2 O 0.25 g, KH 2 PO 4 3.0 g, powdered sulfur 10 g, distilled water 1.0 liter] adjusted to pH 9 were used.
100 ml of this liquid medium was placed in a 500 ml Erlenmeyer flask, sterilized in an autoclave (114 ° C., 20 minutes), and then 1 g of alkaline soil (sandy loam) having a pH of 8.5 to 9.0 was added under aseptic conditions. After shaking culture at 30 ° C. and 150 rpm for 4 weeks, sulfur-oxidizing bacteria were grown. Next, agar was added to a medium having the same composition as described above, and the pH was adjusted to 9 to prepare a modified Starkey agar medium. Next, 0.1 ml of the supernatant of the liquid medium in which the above-mentioned sulfur-oxidizing bacteria were grown was applied to the pH 9 agar medium, and cultured at 30 ° C. for 4 weeks. Three were randomly selected from the obtained colonies, re-added to each of the above-mentioned modified Starkey liquid medium newly prepared for each, and cultured under the same conditions. After culturing, they were mixed to form one sample (hereinafter, referred to as alkaline sulfur-oxidizing bacteria). In addition, as a result of identification, this alkaline sulfur-oxidizing bacterium was Thiobacillus thermosulfatus (Thiobacillus thermosulfatus).
[0022]
(2) Preparation of Soil Amendment II-1 Granular sulfur obtained in the desulfurization step of a refinery, and dry excess sludge obtained from a sewage treatment plant (nitrogen content 3.1 mass%, organic content in total nitrogen content) (Nitrogen content: 28% by mass) was ground by a hammer mill and mixed at a mass ratio of 5: 5. To this mixture, the alkaline sulfur-oxidizing bacteria cultured in the above (1) were added in an amount of 2.0 × 10 4 cfu per 1 g of the obtained soil conditioner, and the mixture was mixed well. , To form a soil improving material II-1 so as to have a diameter of about 3 to 5 mm.
(3) Improvement of soil pH Example 1 (2) was the same as Example 1 (2) except that the soil conditioner II-1 obtained in (2) was used instead of the soil conditioner I-1. The same operation as described above was performed. The results are shown in Table 2.
[0023]
Reference Example 1
(1) Growth of Acid Sulfur-Oxidizing Bacteria In Example 4 (1), a modified Starkey liquid medium adjusted to pH 5 was used as a liquid medium, and a modified Starkey agar medium adjusted to pH 5 was used as an agar medium. Except for the above, the same operation as in Example 4 (1) was performed to obtain a sample of sulfur-oxidizing bacteria (hereinafter, referred to as acidic sulfur-oxidizing bacteria). As a result of the identification, this acidic sulfur-oxidizing bacterium was identified as Thiobacillus thiooxidans (Thiobacillus).
thioxidans).
(2) Preparation of material II-2 Same as Example 4 (2) except that in Example 4 (2), the acidic sulfur-oxidizing bacteria obtained in (1) above were used instead of the alkaline sulfur-oxidizing bacteria. To prepare a material II-2.
(3) Improvement of soil pH Same as Example 4 (3) except that in Example 4 (3), the material II-2 obtained in (2) above was used instead of the soil improving material II-1. Operation. The results are shown in Table 2.
[0024]
[Table 2]
【The invention's effect】
According to the present invention, sulfur and organic matter having a specific nitrogen content, or further, containing certain sulfur-oxidizing bacteria, the pH of alkaline soil, particularly strongly alkaline soil, without adversely affecting the growth of plants Thus, it is possible to provide an easy-to-handle and low-cost soil improving material that can effectively lower the pH to a value suitable for plant growth.
Further, by adding the soil improver to an alkaline soil, particularly a strongly alkaline soil, the pH of the soil can be efficiently reduced, and the soil can be improved to a pH suitable for plant growth.
Claims (7)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003061202A JP4406721B2 (en) | 2003-03-07 | 2003-03-07 | Soil improving material and method for improving soil pH using the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003061202A JP4406721B2 (en) | 2003-03-07 | 2003-03-07 | Soil improving material and method for improving soil pH using the same |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| JP2004269651A true JP2004269651A (en) | 2004-09-30 |
| JP2004269651A5 JP2004269651A5 (en) | 2007-03-15 |
| JP4406721B2 JP4406721B2 (en) | 2010-02-03 |
Family
ID=33123483
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2003061202A Expired - Fee Related JP4406721B2 (en) | 2003-03-07 | 2003-03-07 | Soil improving material and method for improving soil pH using the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4406721B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102668759A (en) * | 2012-05-11 | 2012-09-19 | 江苏江南园林建筑工程有限公司 | Method for improving alkalescent soil |
| CN103484128A (en) * | 2013-08-29 | 2014-01-01 | 南京农业大学 | Saline-alkali soil conditioner, and preparation method and application thereof |
| CN115286090A (en) * | 2022-08-22 | 2022-11-04 | 深圳市水务规划设计院股份有限公司 | FeS-IHP composite material and preparation method and application thereof |
-
2003
- 2003-03-07 JP JP2003061202A patent/JP4406721B2/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102668759A (en) * | 2012-05-11 | 2012-09-19 | 江苏江南园林建筑工程有限公司 | Method for improving alkalescent soil |
| CN103484128A (en) * | 2013-08-29 | 2014-01-01 | 南京农业大学 | Saline-alkali soil conditioner, and preparation method and application thereof |
| CN103484128B (en) * | 2013-08-29 | 2015-07-29 | 南京农业大学 | A kind of alkaline land modifying agent and preparation method thereof and application thereof |
| CN115286090A (en) * | 2022-08-22 | 2022-11-04 | 深圳市水务规划设计院股份有限公司 | FeS-IHP composite material and preparation method and application thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4406721B2 (en) | 2010-02-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU722058B2 (en) | Compost decontamination of DDT contaminated soil | |
| JPH06500495A (en) | Controlled release of microbial nutrients and ecological remediation methods | |
| JPH07500807A (en) | Establishment of optimal soil conditions through natural formation of cultivated land | |
| CN104327858A (en) | Soil heavy metal compound stabilizer and method using soil heavy metal compound stabilizer for passivation of soil heavy metals | |
| US20070219096A1 (en) | Method of sustaining plant growth in toxic substrates polluted with heavy metal elements as well as fertilization and beneficiation of normal horticultural and agricultural soils | |
| Matosic et al. | Tillage, manure and gypsum use in reclamation of saline-sodic soils | |
| CN106995704A (en) | A kind of renovation agent, its preparation method and the method with its restoration of soil polluted by heavy metal | |
| JP5205588B2 (en) | Culture soil improvement material and culture soil containing artificial zeolite | |
| US20100099166A1 (en) | Compositions and Methods for Enhancing Plant Growth by Chemical Oxygenation of Soils | |
| Shrestha et al. | Determination of phosphorus saturation level in relation to clay content in formulated pond muds | |
| JP2006020553A (en) | Greening material and greening construction method using the same | |
| WO2020022933A1 (en) | Method of remediation of contaminated earth | |
| JP4406721B2 (en) | Soil improving material and method for improving soil pH using the same | |
| JP2736837B2 (en) | Microbial treatment of purified water cake | |
| US20050257586A1 (en) | Method of sustaining plant growth in hazardous substrates, limiting the mobility of substrate contaminants, and beneficiation of normal soils | |
| US20030140670A1 (en) | Method of sustaining plant growth in toxic substrates polluted with heavy metal elements | |
| KR100537986B1 (en) | Organic ferment complex fertilizer manufacturing process | |
| JPS63260888A (en) | Soil improver | |
| RU2738482C1 (en) | Recultivation method of soil contaminated with oil and oil products | |
| KR102244433B1 (en) | Manufacturing method of soil Conditioner Composition containing complex microorganism and the soil Conditioner Composition prepared therefrom | |
| JPH09188585A (en) | Immobilized product of microorganism | |
| JP7100076B2 (en) | Soil conditioner and its manufacturing method | |
| RU2722697C1 (en) | Agent for reducing arsenic mobility in soil | |
| KR100872862B1 (en) | Remediation of the contaminated soil | |
| KR920004711B1 (en) | Use of calcium sulphate to improve the fermentation of organic fertilizers |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A711 Effective date: 20040702 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20040702 |
|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20051128 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20070125 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20090316 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20090331 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20090609 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20090924 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20091014 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20121120 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20121120 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20131120 Year of fee payment: 4 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |