JP4217232B2 - Formation method of submerged plant group using artificial floating island for submerged plant - Google Patents

Formation method of submerged plant group using artificial floating island for submerged plant Download PDF

Info

Publication number
JP4217232B2
JP4217232B2 JP2005220722A JP2005220722A JP4217232B2 JP 4217232 B2 JP4217232 B2 JP 4217232B2 JP 2005220722 A JP2005220722 A JP 2005220722A JP 2005220722 A JP2005220722 A JP 2005220722A JP 4217232 B2 JP4217232 B2 JP 4217232B2
Authority
JP
Japan
Prior art keywords
water
submerged plant
submerged
floating island
plant
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.)
Active
Application number
JP2005220722A
Other languages
Japanese (ja)
Other versions
JP2007029058A (en
Inventor
洋 久保田
義彦 島多
昭太 袋
Original Assignee
株式会社フジタ
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 株式会社フジタ filed Critical 株式会社フジタ
Priority to JP2005220722A priority Critical patent/JP4217232B2/en
Publication of JP2007029058A publication Critical patent/JP2007029058A/en
Application granted granted Critical
Publication of JP4217232B2 publication Critical patent/JP4217232B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • Y02P60/216

Description

本発明は人工浮島に関する技術で、特に、沈水植物に適した植栽環境を確保し、沈水植物の形成を促進して水質浄化を効率的に進めるのに適用して有効な技術である。   The present invention is a technique related to an artificial floating island, and is particularly effective when applied to secure a planting environment suitable for a submerged plant, promote the formation of a submerged plant, and promote water purification efficiently.
池や湖沼、河川などに人工の浮体を浮かべ、それにヨシやキショウブなどの抽水植物を植栽する人工浮島は、水質浄化、生物の生息場、消波、景観の向上等の機能を有し、閉鎖性水域の水質浄化、消波構造物として適用されている。かかる人工浮島には、これまでにも様々な構造が提案されている。   Artificial floating islands that float artificial floating bodies in ponds, lakes, rivers, etc., and plant extraction plants such as reeds and kishobu, have functions such as water purification, biological habitat, wave suppression, landscape improvement, etc. It is applied as a water purification and wave-dissipating structure in closed waters. Various structures have been proposed for such artificial floating islands.
一方、車軸藻、クロモ、フサモ、エビモ等々の水辺の沈水植物(沈水植物とは、原則、水面下に根・茎・葉のすべてが存在する植物であるが、ある時期にはミズニラのように葉先が水面上にでるものや、キクモのように水面上で花を咲かせる種もいる)群落は、閉鎖性水域の汚濁に伴う透明度の減少により、これらの沈水植物群落が生息していた水底に光が到達しなくなった結果、その多くが消失した。現在沈水植物は、全国各地で絶滅および絶滅が危惧されている。日本では水草の1/3がレッドデータブックに記載されている。   On the other hand, submerged plants in the waterside such as axle algae, chromo, fusamo, shrimp, etc. (Submerged plants are basically plants that have roots, stems, and leaves under the surface of the water. (There are some species that have leaf tips on the surface of the water and some species that bloom flowers on the surface of the water, such as spider spiders.) As for the communities, the bottom of these submerged plant communities inhabited by the decrease in transparency due to the pollution of the closed waters. As a result, many of them disappeared. Currently submerged plants are threatened with extinction and extinction throughout the country. In Japan, 1/3 of aquatic plants are listed in the Red Data Book.
最近になってこれらの沈水植物群落には、水中の栄養塩の取り込み、底泥の巻上げ防止、動物プランクトンの隠れ家、底生動物の棲み家など水質浄化を初めとする様々な機能があることが明らかになってきた。生物の多様性の保全と合わせて、沈水植物群落を含めた水辺植性帯の復元の試みが自然再生事業として始まっている。   Recently, these submerged plant communities have various functions including water purification such as uptake of nutrients in the water, prevention of rolling up of bottom mud, zooplankton retreat, benthic itch house, etc. It has become clear. Along with the conservation of biodiversity, an attempt to restore waterside vegetation zones, including submerged plant communities, has begun as a nature restoration project.
沈水植物の植栽基盤としては、例えば特許文献1に、植栽基盤の適切な水位変化が得られるように植栽基盤を上下できる構成が開示されている。また、特許文献2には、沈水植物としての明言はないものの、水に全体が水没して沈水植物と思われるものが、水上から水中に向かってゆるやかに傾斜させた重りを入れた植生基盤に生えている構成が開示されている。
特開平11−275990号公報 特開2002−119157号公報
As a planting base of a submerged plant, for example, Patent Document 1 discloses a configuration in which the planting base can be moved up and down so that an appropriate water level change of the planting base can be obtained. Moreover, although there is no statement as a submerged plant in patent document 2, what seems to be a submerged plant because the whole is submerged in water is a vegetation base with a weight that is gently inclined from the surface of the water toward the water. The growing configuration is disclosed.
JP-A-11-275990 JP 2002-119157 A
沈水植物の再生、復元を試みるについては、次のような課題があることに本願発明者は気づいた。   The inventor of the present application has found that there are the following problems regarding the regeneration and restoration of submerged plants.
すなわち、復元を試みるような水域では水の汚濁がかなりの程度進んで、透明度が低い。そのため、沈水植物群落は従来生息していた水深の深い場所では、光が届かず生育できない。水域の透明度にも依存するが、例えば、苗株や種子を散布しても水深30cm程度の浅い水域でしか発芽、生育することができない。   In other words, in water areas where restoration is attempted, water pollution has advanced considerably and transparency is low. For this reason, submerged plant communities cannot grow in the deep water areas where they have traditionally inhabited because light does not reach them. Although depending on the transparency of the water area, for example, even if seedlings and seeds are sprayed, they can germinate and grow only in a shallow water area of about 30 cm in depth.
植栽や種子散布当初は沈水植物群落が一旦は再生するが、そのような浅い水深ではヨシなどの抽水植物やヒシなどの浮葉植物が生育できるため、最終的には沈水植物群落はこれらの植物が繁茂することにより、光を十分に得ることができず消失してしまう。沈水植物群落の再生、復元に大きな課題が残っている。   At the beginning of planting and seed dispersal, submerged plant communities are once regenerated, but at such shallow depths, water-drawn plants such as reeds and floating leaf plants such as casters can grow. As a result of overgrowth, sufficient light cannot be obtained and vanishes. Great challenges remain in the regeneration and restoration of submerged plant communities.
これまでに沈水植物を含む水生植物群落を復元する浮島が提案されているが、例えば特許文献1、2に記載の浮島構造の構成では、抽水植物や植生移行帯に焦点を当てているため、必ずしも沈水植物の復元に焦点を当てているとはいえない。従って、最適な沈水植物の植栽基盤はどのようなものかについての詳細は分からない。   So far, floating islands that restore aquatic plant communities including submerged plants have been proposed, but for example, in the configuration of the floating island structure described in Patent Documents 1 and 2, because the focus is on the extracted plants and vegetation transition zone, It does not necessarily focus on the restoration of submerged plants. Therefore, the details of what is the optimal planting base for submerged plants are not known.
そこで、本発明者は沈水植物の植栽基盤に関して種々研究、調査を行った結果、以下の問題点があることを見出した。かかる問題点は、これまでの湖沼沿岸域における沈水植物郡落の再生の試みの結果得られたものであり、従来の浮島の構造では、再生、復元は難しいと言える。   Therefore, as a result of various studies and investigations regarding the planting base of submerged plants, the present inventor has found that there are the following problems. This problem was obtained as a result of previous attempts to regenerate submerged plant counties in the coastal area of the lake, and it can be said that regeneration and restoration are difficult with the conventional floating island structure.
草食性や雑食性魚類が沈水植物に与える食害
ソウギョ等の草食性の魚やハクレン等の雑食性の魚は、過去に湖沼等に繁茂する水草を除去するために人工的に放流され、沈水植物群落を消失させてしまった。このような食性の魚類が含まれる水域では、沿岸域に植栽することはもとより、沈水植物用の浮島を設置する際にも侵入防止策を講じなければ沈水植物を生育することはできない。
Damage caused by herbivorous and omnivorous fish on submerged plants Herbivorous fish such as grass carp and omnivorous fish such as clams are artificially released in order to remove aquatic plants that have flourished in lakes and the like in the past. Has disappeared. In such a water area containing edible fish, it is not possible to grow submerged plants without taking intrusion prevention measures when setting up floating islands for submerged plants as well as planting in coastal areas.
プランクトン食性魚の蝟集による沈水植物群落で増殖した動物性プランクトンの捕食
沈水植物群落内では、水域汚濁の原因となる植物プランクトンを捕食する(水質浄化作用のある)動物プランクトンが増殖することが知られている。しかし、植物群落繁茂前や繁茂したとしても雑食性や動物プランクトン食性の魚類が数多く蝟集すると、動物プランクトンが食い尽くされてしまい、動物プランクトンによる水質浄化機能を十分に発揮することができなくなる。かかる魚類の防止策を講じる必要がある。
Predation of zooplankton grown in a submerged plant community by collecting plankton-eating fish In a submerged plant community, it is known that zooplankton that prey on phytoplankton (which has water purification effects) grows. Yes. However, if a large number of omnivorous and zooplankton-eating fishes are collected even before the plant community has grown, the zooplankton will be consumed, and the water purification function by the zooplankton will not be fully demonstrated. It is necessary to take measures to prevent such fish.
カモ等の鳥類による沈水植物の食害、植栽基盤の攪乱
カモ等の鳥類は、浮島を営巣・休息の場とするだけでなく、水草を摂餌してしまう。また、浮島内を遊泳することで、水掻きで荒らしたり、植栽した沈水植物をくちばしで抜いてしまう等生育初期の沈水植物が植栽された植栽基盤を撹乱してしまう。かかる攪乱を防ぐ必要がある。
Damage of submerged plants by birds such as ducks and disturbance of planting bases Birds such as ducks not only make floating islands a nesting and resting place, but also feed on aquatic plants. In addition, swimming in the floating islands disturbs the planting base on which submerged plants in the early stage of growth, such as roughening with water scraping or pulling out planted submerged plants with beaks, are planted. It is necessary to prevent such disturbance.
植物種や水質により生育可能水深が異なる
水域の水質により汚濁の程度が異なり、それに伴い光の透過する水深が大きく異なる。沈水植物種やその生育段階によって光要求条件が異なるため、植栽基盤の位置を上下させる必要がある。
The depth of viable water varies depending on the plant species and water quality The degree of pollution varies depending on the water quality of the water area, and the water depth through which light passes varies greatly. Since the light requirement varies depending on the submerged plant species and its growth stage, it is necessary to move the planting base up and down.
風波の影響による沈水植物の繁茂限界
沈水植物群落を復元する上での問題として、風波の影響による植物の繁茂限界がある。風や波が強い水域では植栽基盤が移動し、沈水植物群落の根の固着能力が非常に乏しいため、ある一定以上の風波では生育することができない。このため、例えば、霞ヶ浦等の沿岸域における沈水植物群落の復元においては、粗朶等の消波施設が必要となっている。従来の浮島構造ではこれらの消波機能については考慮されておらず、このような風波の強い地点では、沈水植物群落の生育は非常に難しいと言える。
The limit of overgrowth of submerged plants due to the influence of wind waves As a problem in restoring submerged plant communities, there is the limit of overgrowth of plants due to the effects of wind waves. In a strong wind and wave area, the planting base moves, and the ability of the roots of submerged plant communities to stick is very poor. For this reason, for example, in order to restore submerged plant communities in coastal areas such as Kasumigaura, wave-dissipating facilities such as rough ridges are required. In the conventional floating island structure, these wave-dissipating functions are not taken into consideration, and it can be said that it is very difficult to grow a submerged plant community at a point where such a wind wave is strong.
他水域からの沈水植物種の持ち込み
これまでの浮島では、生育した苗を植栽する形や土砂に種子を投入したものである。市販品では、かかる苗や種子は復元を希望する水域からのものではなく、そのため他水域からの沈水植物種の移入に繋がり、その結果として遺伝的撹乱が起き、在来種の復元とはならない。本来の意味での自然再生とは異なるものとなる。
Bringing submerged plant species from other waters So far, floating islands have been planted with seedlings in the form of planting grown seedlings. In commercial products, such seedlings and seeds are not from the waters that are desired to be restored, which leads to the transfer of submerged plant species from other waters, resulting in genetic disturbances that do not restore native species . This is different from natural regeneration in the original sense.
このように沈水植物用人工浮島の構成には解決すべき問題点が多数あり、かかる問題点の解決を通して初めて沈水植物による水域汚濁の改善等の水質浄化作用が行われものである。   Thus, there are many problems to be solved in the construction of the artificial floating island for submerged plants, and the water purification effect such as improvement of water pollution by submerged plants is performed for the first time through the solution of such problems.
本発明の目的は、沈水植物用人工浮島を、沈水植物を餌等とする動物から保護することにある。   An object of the present invention is to protect an artificial floating island for a submerged plant from animals that feed on the submerged plant.
他の本発明の目的は、沈水植物用人工浮島を用いて水域での沈水植物群落の復元をも含めた形成を適切に行うことにある。   Another object of the present invention is to appropriately perform formation including restoration of a submerged plant community in a water area using an artificial floating island for a submerged plant.
他の本発明の目的は、沈水植物用人工浮島を用いて設置水域の水質浄化を適切に行うことにある。   Another object of the present invention is to appropriately purify water in an installation water area using an artificial floating island for a submerged plant.
本発明の前記ならびにその他の目的と新規な特徴は、本明細書の記述および添付図面から明らかになるであろう。   The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.
本願において開示される発明のうち、代表的なものの概要を簡単に説明すれば、次のとおりである。   Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.
本発明は、沈水植物の生育可能な光透過率の限界水深が前記沈水植物の成長により深くなるのに従って、前記沈水植物が植栽された沈水植物用人工浮島の植栽基盤を前記限界水深の範囲内で深くするステップと、前記植栽基盤に植栽された沈水植物の種子あるいは胞子を水底に飛散させるステップと、前記飛散した種子あるいは胞子に基づき前記水底に沈水植物を生やすステップとを有することを特徴とする沈水植物用人工浮島を用いた沈水植物群の形成方法である。かかる構成において、前記植栽基盤は、前記水底に沈水植物が根付いた時点で撤去することを特徴とする The present invention provides the planting base of the artificial floating island for submerged plants in which the submerged plant is planted as the limit water depth of the light transmittance capable of growing the submerged plant becomes deeper as the submerged plant grows. A step of deepening within a range, a step of scattering seeds or spores of the submerged plant planted on the planting base to a bottom of the water, and a step of growing a submerged plant on the bottom of the water based on the scattered seeds or spores. It is the formation method of a submerged plant group using the artificial floating island for submerged plants characterized by this. In this configuration, the planting base is removed when a submerged plant is rooted on the water bottom .
本願において開示される発明のうち、代表的なものによって得られる効果を簡単に説明すれば以下のとおりである。   Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.
本発明によれば、沈水植物用人工浮島の設置水域に沈水植物群落の形成が可能となる。特に、水底に沈水植物を生やすことが確実に行われるようになった時点で、撤去すれば、周囲景観の観点からも好ましい。 According to the present invention, it is possible to form a submerged plant community in an installation water area of an artificial floating island for a submerged plant. In particular, it is preferable from the viewpoint of the surrounding landscape if it is removed at the time when the submerged plant is reliably grown on the bottom of the water.
以下、本発明の実施の形態を図面に基づいて詳細に説明する。なお、実施の形態を説明するための全図において、同一の部材には原則として同一の符号を付し、その繰り返しの説明は省略する場合がある。   Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof may be omitted.
本発明は、沈水植物用の人工浮島の有する構造上の問題点を解決すると共に、沈水植物群落の植栽基盤を沈水植物の生育に必要な光条件の確保が行える水深に設置し、沈水植物だけを植栽して人工浮島とすることで、抽水植物や浮葉植物の侵入を防ぎ、結果として水域の水底に沈水植物群落を復元することを含めた沈水植物群落の形成が行える。また、沈水植物用の人工浮島と抽水植物用の人工浮島とをセットとして用いる場合においても、沈水植物用の人工浮島を区画化することにより抽水植物の侵入を防止し、沈水植物のみの群落を確保することができる。   The present invention solves the structural problems of an artificial floating island for a submerged plant and installs the planting base of the submerged plant community at a water depth that can ensure the light conditions necessary for the growth of the submerged plant. By planting only an artificial floating island, it is possible to prevent submerged plants and floating leaf plants from entering, and as a result, to form submerged plant communities that include restoring submerged plant communities to the bottom of the water area. In addition, even when using artificial floating islands for submerged plants and artificial floating islands for extracted plants as a set, it is possible to prevent the intrusion of extracted plants by partitioning the artificial floating island for submerged plants. Can be secured.
さらには、かかる沈水植物用人工浮島を用いた池や湖沼等の水質の浄化において、沈水植物群落の水質浄化機能の一つに水質浄化能の高い動物プランクトンの隠れ家としての機能があるが、動物プランクトンの密度、種類数が非常に少ないか、あるいは小型の動物プランクトン群集しか存在しない水域においてもかかる浄化機能を高めることができる方法をも提案する。   Furthermore, in the purification of water quality such as ponds and lakes and marshes using such artificial floating islands for submerged plants, one of the water purification functions of submerged plant communities has a function as a hideout for zooplankton with high water purification capability. We also propose a method that can enhance the purification function even in waters where the density and number of plankton are very small, or where only small zooplankton communities exist.
すなわち、本発明により、次のような効果が得られる。多孔質部材に砂や土または軽量骨材を投入する形式により植栽基盤の安定性を確保し、波等により砂や土が消失するのを防ぐとともに、沈水植物の生育を促進することができる。砂や軽量骨材を充填した沈水植物植栽ポッドを充填することにより、砂の充填量を格段に少なくすることができ、軽量化に伴い浮体の大きさを小さくすることができ、コストも安価にすることができる。水質、植物の生育段階に合わせて植栽基盤の位置を変えることにより、沈水植物の生育を促進することができる。   That is, according to the present invention, the following effects can be obtained. It is possible to ensure the stability of the planting base by putting sand, soil or lightweight aggregate into the porous member, prevent the sand and soil from disappearing due to waves etc., and promote the growth of submerged plants. . Filling a submerged plant planting pod filled with sand or lightweight aggregate can significantly reduce the amount of sand filling, reduce the size of the floating body as the weight is reduced, and reduce costs Can be. By changing the position of the planting base according to the water quality and the growth stage of the plant, the growth of the submerged plant can be promoted.
草食、雑食、動物プランクトン食性の魚類の浮島内部への侵入を防ぎ、沈水植物の生育を促進することができる。鳥類からの捕食、植栽基盤の撹乱を防ぎ、沈水植物の生育を促進することができる。   It prevents herbivorous, omnivorous and zooplankton-eating fish from entering the floating islands and promotes the growth of submerged plants. Predation from birds, planting base disturbance can be prevented, and the growth of submerged plants can be promoted.
対象水域の水質浄化を効果的に行い、最終的には沈水植物用浮島の周辺の水底に沈水植物群落を再生、生態系の水質浄化機能を高め、水域全域への沈水植物群落を復元することができる。水域特有の沈水植物群落を沈水植物浮島に復元することができる。水域の水底土砂に含まれる種子(埋土種子)が少ない場合においても、発芽・育成・苗株植え付けにより効果的に在来の(水域特有の)沈水植物群落を復元することができる。在来種の沈水植物の群落を浮島周辺の水底に復元、水域全域へ拡大、在来の沈水植物群落を復元することができる。かかる水質浄化、復元速度を高めることができる。   Effectively purify the target water area, and finally regenerate submerged plant communities on the bottom of the floating island for submerged plants, enhance the water purification function of the ecosystem, and restore the submerged plant communities throughout the water area Can do. The submerged plant community peculiar to the water area can be restored to the submerged plant floating island. Even when the seeds (buried seeds) contained in the bottom sediment of the water area are small, it is possible to effectively restore the native (water area specific) submerged plant community by germination, breeding and seedling planting. A community of native submerged plants can be restored to the bottom of the floating island, expanded to the entire body of water, and a native submerged plant community can be restored. Such water purification and restoration speed can be increased.
抽水浮島の消波、沈水植物とは異なる水質浄化効果により、より多機能で効果的な水質浄化が可能になる。   The water purification effect that is different from the wave extinction of submerged floating islands and submerged plants enables more effective and effective water purification.
植物プランクトンを食べるミジンコ等の動物プランクトン、特に大型のミジンコを増加させることができ沈水植物用浮島の水質浄化効果を高めることができる。在来の動物プランクトン群集を発生、培養したものを用いることにより、他からの移入種の問題も解消する。   Zooplankton such as Daphnia, which eats phytoplankton, particularly large Daphnia can be increased, and the water purification effect of floating islands for submerged plants can be enhanced. By using the native zooplankton community that has been generated and cultured, the problem of introgression from other species is also eliminated.
以下、各実施の形態をかかる効果との関係で説明することにより、本願発明についてより具体的に説明する。   Hereinafter, the present invention will be described more specifically by describing each embodiment in relation to such effects.
(実施の形態1)
図1は、本発明の一実施の形態の沈水植物用人工浮島の実施例を模式的に示す側面図である。図2(a)は本発明で使用するフロートとそのフレームの構成を示す斜視図であり、(b)はフレーム内に植栽基盤を設けた状況を示す斜視図である。図3(a)、(b)は、本発明で水位の調節を行う状況を示す説明図である。
(Embodiment 1)
FIG. 1 is a side view schematically showing an example of an artificial floating island for a submerged plant according to an embodiment of the present invention. FIG. 2A is a perspective view showing the structure of a float and its frame used in the present invention, and FIG. 2B is a perspective view showing a situation where a planting base is provided in the frame. 3 (a) and 3 (b) are explanatory views showing the situation where the water level is adjusted in the present invention.
沈水植物用人工浮島10の基本的な構成は、沈水植物を生育させる植栽基盤20と、それを支持する支持体30、かかる構成を水中に維持するための浮体としてのフロート40とから構成する。   The basic structure of the artificial floating island 10 for a submerged plant includes a planting base 20 on which a submerged plant is grown, a support 30 that supports the submerged plant, and a float 40 that serves as a floating body for maintaining the structure in water. .
フロート40の素材は塩ビ管等の中空パイプ40aや、あるいは発砲スチロール、木材、古タイヤ等であり、植栽基盤20等を含めた沈水植物用人工浮島10の全体構成を浮かべておけるだけの浮力を持っている材質であれば良い。   The material of the float 40 is a hollow pipe 40a such as a PVC pipe, or foamed polystyrene, wood, old tires, etc., and the buoyancy that can float the entire structure of the artificial floating island 10 for submerged plants including the planting base 20 and the like. Any material that has
支持体30は、図2(a)、(b)に示すように、フレーム31を構成するアングル31a、植栽基盤20等を囲うシート32を構成するブルーシート32aからなる。アングル31aは、鋼材やプラスチック製、木製等で形成され、枠状に組み合わせて、図2(a)に示すように、フレーム31が形成されている。特に、風波等が問題となる場所では十分な強度を持ち、プラスチックには生分解性でないものを用いる。かかるフレーム31が、フロート40に接続されている。   As shown in FIGS. 2A and 2B, the support 30 is composed of an angle 31 a constituting the frame 31, a blue sheet 32 a constituting a sheet 32 surrounding the planting base 20 and the like. The angle 31a is formed of steel, plastic, wood, or the like, and is combined in a frame shape to form a frame 31 as shown in FIG. In particular, in a place where wind waves or the like are a problem, a plastic having a sufficient strength and non-biodegradable plastic is used. Such a frame 31 is connected to the float 40.
また、植栽基盤20の下部、側面には、シート32が設けられ、植栽基盤20内に充填した砂や土または軽量骨材の流出が防止されている。シート32の材質としては、ブルーシートや建築・土木で用いる工事用のシート等の遮水性のシートを用いるとよい。   Moreover, the sheet | seat 32 is provided in the lower part and side surface of the planting base 20, and the outflow of the sand and soil with which the planting base 20 was filled, or a lightweight aggregate is prevented. As the material of the sheet 32, a water-proof sheet such as a blue sheet or a construction sheet used in construction or civil engineering may be used.
植栽基盤20は、多孔質部材20aに砂や土または軽量骨材等が充填されている。かかる多孔質部材20aとしては、例えば、軽量の化学合繊マットやヤシ繊維性のマットなどを用いることができる。かかる植栽基盤20に充填する砂等は、現地の沈水植物用人工浮島10の設置水域の水底の土砂を充填したりすることもできる。多孔質部材20aを用いることにより、風波等による充填した土砂や軽量骨材の基盤内からの流出を防止し、植栽基盤20を安定化することができる。   As for the planting base 20, the porous member 20a is filled with sand, earth, lightweight aggregate or the like. As the porous member 20a, for example, a lightweight chemical synthetic mat or a palm fiber mat can be used. The sand or the like to be filled in the planting base 20 can be filled with soil and sand at the bottom of the area where the artificial floating island 10 for submerged plants is installed. By using the porous member 20a, it is possible to prevent the soil and sand filled with wind waves or the like from flowing out of the base of the lightweight aggregate, and to stabilize the planting base 20.
因みに、軽量骨材とはガラスや膨張頁岩等を原料とし、これを人工的に焼成・発泡して得られる内部に空隙を保有し、表面が緻密なガラスで覆われ砂よりも軽くて強い骨材である。一般的な商品名としてメサライトやGライト、アサノスーパーライト等が知られている。   By the way, lightweight aggregate is made of glass, expanded shale, etc. as a raw material, and there is a void in the inside obtained by artificial firing and foaming, and the surface is covered with dense glass, lighter and stronger bone than sand It is a material. Mesalite, G light, Asano superlight, etc. are known as common product names.
さらには、多孔質部材20aに直接土砂等を充填することなく、土砂等を植栽ポッド21に充填したものを多孔質部材20aに充填しても構わない。かかる構成を採用すれば、植栽基盤20の軽量化を図ることができる。   Further, the porous member 20a may be filled with a material obtained by filling the planting pod 21 with earth and sand without directly filling the porous member 20a with earth and sand. If this structure is employ | adopted, the weight reduction of the planting base 20 can be achieved.
植栽基盤20の厚みは、沈水植物の根が十分に張ることができる厚さ以上とする。沈水植物の種類にもよるが、平均的には、例えば5cm以上とすればよい。植栽ポッド21は、布織布やヤシ繊維製などの園芸等で用いられるポッドを使用すればよい。かかる植栽ポッド21に、砂等を充填すればよい。植栽ポッド21を用いることで、使用する砂や土砂の量を大きく削減することができる。   The thickness of the planting base 20 is set to be equal to or greater than a thickness that allows the roots of the submerged plant to be sufficiently stretched. Depending on the type of submerged plant, on average, it may be, for example, 5 cm or more. The planting pod 21 may be a pod used in horticulture such as cloth, woven fabric or palm fiber. What is necessary is just to fill this planting pod 21 with sand. By using the planting pod 21, the amount of sand and earth and sand used can be greatly reduced.
あるいは、植栽ポッド21等の充填ポッドを用いる代わりに、スポンジ、ロックウール、スラグウール等の植栽材を用いることで土を使わず植栽することができる。すなわち、沈水植物の種、胞子、あるいは苗等を、ロックウール等の植栽材を用いて土を使わずに植栽する。かかる植栽した植栽材を、例えば、植栽基盤20の化学合繊マットやヤシ繊維製のマット等の所定位置に差すようにして設ければよい。植栽ポッド21の代わりにスポンジ、ロックウール、スラグウール等の植栽材を用いることで、使用する土砂の量をゼロにすることもできる。   Or it can plant without using soil by using planting materials, such as sponge, rock wool, and slag wool, instead of using filling pods, such as planting pod 21. That is, a seed, spore, or seedling of a submerged plant is planted without using soil using a plant material such as rock wool. What is necessary is just to provide this planted planting material, for example so that it may be put in predetermined positions, such as the chemical synthetic fiber mat of the planting base 20, and the mat | matte made from palm fiber. By using a planting material such as sponge, rock wool, slag wool or the like instead of the planting pod 21, the amount of earth and sand to be used can be made zero.
このように土砂等の量をゼロあるいは大きく低減化することで、植栽基盤20を軽量化し、フロート40等の浮体設備の縮小化、さらには植栽基盤20の層厚を大きくすることも可能となる。   Thus, by reducing the amount of earth and sand to zero or greatly, the planting base 20 can be reduced in weight, the floating equipment such as the float 40 can be reduced, and the layer thickness of the planting base 20 can be increased. It becomes.
植栽基盤20あるいは植栽ポッド21に砂を充填する場合は、山砂や川砂がよい。海砂は塩分が沈水植物の生育を阻害するため好ましくない。但し、川砂の中には水生植物の種子が混入していることがあるので、設置水域の沈水植物の復元を意図する場合には、注意を要する。また、砂、土ともに市販品を使用する場合には、成分表示に注意してカルシウム等の含有量が少ないものを選択し、アルカリ性のものは使用しない方がよい。   When the planting base 20 or the planting pod 21 is filled with sand, mountain sand or river sand is preferable. Sea sand is not preferred because salinity inhibits the growth of submerged plants. However, there are cases where seeds of aquatic plants are mixed in the river sand, so care must be taken when restoring the submerged plants in the installation water area. In addition, when using commercially available products for both sand and earth, it is better not to use alkaline ones with a low content of calcium or the like, paying attention to the component labeling.
沈水植物を植栽基盤20等に植えるには、多孔質部材20aに砂や軽量骨材を充填した植栽基盤20に直接苗株を植えつける。あるいは、植栽ポッド21に苗株を植えつけた後、多孔質部材20aに充填する方法で植栽するとよい。   In order to plant a submerged plant on the planting base 20 or the like, a seedling is planted directly on the planting base 20 in which the porous member 20a is filled with sand or light aggregate. Or after planting a seedling in the planting pod 21, it is good to plant by the method of filling the porous member 20a.
かかる植栽に際して、沈水植物用人工浮島10の設置対象水域の水底から採取した土砂に、在来の沈水植物の種子や胞子が埋土種子として多量に存在する場合は、多孔質部材20aに水底採取土砂を充填することで、その水域特有の多様な在来種を沈水植物用人工浮島10に復元できて好ましい。   In such planting, when a large amount of seeds and spores of conventional submerged plants are present as buried seeds in the soil collected from the bottom of the target water area of the submerged artificial floating island 10, the bottom of the porous member 20 a is submerged. Filling the collected soil and sand is preferable because various native species peculiar to the water area can be restored to the artificial floating island 10 for a submerged plant.
また、沈水植物用人工浮島10の設置対象水域の水底から採取した土砂に埋土種子が少量しか含まれない場合は、あらかじめ水底から採取した土砂を、深さ20cm程度に地面を掘削し遮水シートを敷いた場所や大きなバッド等に敷き詰め、水を張り、十分な光条件のもとで在来の沈水植物を発芽させる。発芽、生育させた沈水植物の苗株を、多孔質部材20aに砂や軽量骨材を充填した植栽基盤20に直接植えつける。あるいは植栽ポッド21に植えつけた後、多孔質部材20aに植栽ポッド21を充填すればよい。かかる方法を採用すると、沈水植物用人工浮島10の設置対象水域に存在する在来の群生していた沈水植物を復元することができる。   In addition, when only a small amount of buried seed is contained in the earth and sand collected from the bottom of the target water area of the artificial floating island 10 for submerged plants, the earth and sand collected in advance from the bottom of the water is excavated to a depth of about 20 cm to make the water impermeable. It is spread on a place where a sheet is laid or a large bud, is filled with water, and a native submerged plant is germinated under sufficient light conditions. The seedling of the submerged plant that has sprouted and grown is directly planted on the planting base 20 in which the porous member 20a is filled with sand or light aggregate. Or after planting in the planting pod 21, the planting pod 21 may be filled in the porous member 20a. When such a method is employed, the conventional submerged submerged plants existing in the water area where the artificial floating island 10 for submerged plants is installed can be restored.
植栽基盤20を支持するフレーム31と、浮体のフロート40に接続しているフレーム31との連結位置は上下可変とすることができるように構成されている。すなわち、フレーム31は、図3(a)、(b)に示すように、上下に伸縮させることにより、植栽基盤20の設置水深を調節することができるようになっている。かかる植栽基盤20の水深可変手段としては、例えば、一定間隔おきに穴のあいたアングル33をフレーム31の四隅に設けてフロート40と接続し、植栽基盤20を支持するフレーム31と接続されたアングル34をボルト35等で、適宜高さで固定するとよい。   The connection position of the frame 31 supporting the planting base 20 and the frame 31 connected to the float 40 is configured to be variable up and down. That is, as shown in FIGS. 3A and 3B, the frame 31 can be adjusted up and down to adjust the installation water depth of the planting base 20. As the water depth variable means of the planting base 20, for example, the angles 33 with holes at regular intervals are provided at the four corners of the frame 31 and connected to the float 40, and connected to the frame 31 that supports the planting base 20. The angle 34 may be fixed at an appropriate height with a bolt 35 or the like.
水草の生育可能水深は水質によって大きく異なるため、目安として光の透過率をその生育可能か否かの基準として採用した。すなわち、光の透過率が水面の2%以上、さらに望ましくは20%以上となる水深であれば、沈水植物の生育が可能な生育限界水深とすることができる。   Since the viable depth of aquatic plants varies greatly depending on the water quality, the light transmittance was adopted as a standard for determining whether or not the plants can grow. That is, if the water depth is 2% or more, more preferably 20% or more of the water surface, the growth limit water depth at which a submerged plant can grow can be obtained.
植え付け当初の苗株や発芽初期はなるべく水深を浅くして、光の透過率20%以上でもより十分に光が当たる浅い水深で植物の生育を促進するのが好ましい。茎丈が増加するとともに、光の透過率20%を限度としてその水深まで、植栽基盤20の設置水深を深くしていくのが望ましい。   It is preferable to reduce the water depth as much as possible at the beginning of planting and the early stage of germination, and to promote the growth of plants at a shallow water depth that is sufficiently exposed to light even when the light transmittance is 20% or more. As the stem length increases, it is desirable to increase the depth of installation of the planting base 20 up to the depth of 20% of the light transmittance.
尚、植栽基盤20に勾配をもうけることで、植栽基盤20内で光条件の異なる場を形成し、かかる構成で、同じ植栽基盤20内に水深に応じた多様な沈水植物群落を創出することを可能としても構わない。図4に、沈水植物を含めた水生植物の一覧を示した。   In addition, by creating a gradient in the planting base 20, a place with different light conditions is formed in the planting base 20, and in this configuration, various submerged plant communities according to the water depth are created in the same planting base 20. It does not matter if it is possible to do. FIG. 4 shows a list of aquatic plants including submerged plants.
かかる構成の沈水植物用人工浮島10は、その周囲は、図1に示すように、植栽基盤20の下部から水面にかけて水没部分が、網目サイズ1mm以上、100mm以下のネット51で覆われている。より好ましくは、5mm以上、50mm以下のネットである。かかるネット51の材質は、ポリエチレンやポリプロピレン、ヤシ繊維製等、硬質、軟質を問わない。材質は、難分解性のものや耐水性、耐紫外線のある材質のものとするのが好ましい。   As shown in FIG. 1, the submerged artificial island 10 for a submerged plant is covered with a net 51 having a mesh size of 1 mm or more and 100 mm or less from the bottom of the planting base 20 to the water surface. . More preferably, the net is 5 mm or more and 50 mm or less. The material of the net 51 may be hard or soft, such as polyethylene, polypropylene, and palm fiber. The material is preferably a material that is hardly decomposable, water resistant, or ultraviolet resistant.
網目のサイズは小さい方が良いが、あまり細かくすると浮島内の水の流動を妨げるため孔径1mm以上とし、侵入を防止対象魚類の体長の100mm以下とすることが望ましい。さらに、5mm以上、50mm以下とすればより好ましい。5mm以上であれば、水の出入りの円滑性が確保され、50mm以下であれば、草魚等の特に沈水植物の食害が大きい体長の小さい魚や、動物プランクトンを食する魚に的を絞ることができ好ましい。   The mesh size should be small, but if it is too fine, the flow of water in the floating island will be hindered, so it is desirable that the hole diameter is 1 mm or more, and the body length of the fish to be prevented from entering is 100 mm or less. Furthermore, it is more preferable if it is 5 mm or more and 50 mm or less. If it is 5 mm or more, the smoothness of entering and exiting water is ensured, and if it is 50 mm or less, it is possible to focus on fish with a short body length, such as grass fish, which are particularly damaging to submerged plants, and fish that eat zooplankton. preferable.
かかるネット51を設けることにより、沈水植物の生育を阻害する草食性の魚類や、沈水植物内に生息する動物プランクトンを捕食する魚類が、浮島内の植栽基盤20に侵入することを防ぐことができる。   By providing such a net 51, it is possible to prevent herbivorous fish that inhibit the growth of submerged plants and fish that prey on zooplankton that live in submerged plants from entering the planting base 20 in the floating island. it can.
上記ネット51は、上記草魚等の魚類以外にも、アメリカザリガニ等のザリガニ類の侵入を防止し、ザリガニ類の沈水植物の根きり、茎切断等の被害をも未然に防止することができる。   In addition to fish such as grass fish, the net 51 can prevent intrusion of crayfish such as crayfish, and can prevent damage such as rooting of a submerged plant of crayfish and stalk cutting.
また、植栽基盤20の上方にも、図1に示すように、網目サイズ5mm以上、200mm以下、より好ましくは10mm以上、100mm以下のネット52を設ける。太陽光の透過状況を考えると5mm未満の網目サイズは、好ましくない。より好ましくは、10mm以上であれば、十分である。また、網目サイズが200mmより大きいと、水鳥等が入り、餌等を漁る際に沈水植物の植栽基盤20を攪乱する虞がある。より好ましくは、網目サイズが100mm以下であれば、カモ等の小さな鳥も侵入防止対象とすることができて好ましい。   Further, as shown in FIG. 1, a net 52 having a mesh size of 5 mm or more and 200 mm or less, more preferably 10 mm or more and 100 mm or less is also provided above the planting base 20. Considering the state of sunlight transmission, a mesh size of less than 5 mm is not preferable. More preferably, 10 mm or more is sufficient. On the other hand, if the mesh size is larger than 200 mm, water birds or the like may enter and disturb the submerged plant planting base 20 when fishing for food or the like. More preferably, if the mesh size is 100 mm or less, a small bird such as a duck can be used as an intrusion prevention target.
かかるネット52の材質はポリエチレンやポリプロピレン、ヤシ繊維製等、硬質、軟質を問わない。材質も、難分解、耐紫外光のものを用いるのが好ましい。また、ネット52の太さは太くなると浮島基盤内の沈水植物群落に対する光の透過を妨げるため、丈夫で細めのネット52を使用するのが好ましい。   The material of the net 52 may be hard or soft, such as polyethylene, polypropylene, and palm fiber. It is preferable to use a material that is hardly decomposed and resistant to ultraviolet light. In addition, when the net 52 is thick, it is preferable to use a strong and narrow net 52 because it prevents light from being transmitted to submerged plant communities in the floating island base.
ネット52を設置する場所は、植栽基盤20の上方で、沈水植物の生育を妨げることがない高さであればどこでも構わない。フロート下部、水面下に設置すると景観保護という観点からは望ましい。このネット52を設置することにより、水草を捕食したり、または浮島内に侵入して植栽基盤20を撹乱するカモ等の水鳥、さらには鳥類による悪影響を最小限にすることができ、沈水植物群落の発芽、生育を促進することができる。   The place where the net 52 is installed may be anywhere above the planting base 20 as long as it does not hinder the growth of submerged plants. From the viewpoint of landscape protection, it is desirable to install it below the float and below the surface of the water. By installing this net 52, it is possible to minimize the adverse effects of water birds such as ducks and birds that prey on aquatic plants or break into floating islands and disturb planting base 20, and birds. Germination and growth of communities can be promoted.
因みに、かかる鳥被害が発生しないか、あるいは問題とならない場合には、勿論ネット52の設置は必要ない。図3(a)、(b)では、かかるネット52の構成のない例を使用した。   Incidentally, if such bird damage does not occur or does not become a problem, it is of course unnecessary to install the net 52. In FIGS. 3A and 3B, an example in which the net 52 is not configured is used.
(実施の形態2)
本実施の形態では、沈水植物用人工浮島10と抽水植物用人工浮島60とを併置した構成について説明する。かかる構成を採用することで、例えば、沈水植物用人工浮島10の植栽基盤20の風波による影響をより少なくし、且つ抽水植物用人工浮島60の作用により水の透明度を向上させて沈水植物がより生育し易いようにすることができる。図5は、沈水植物用人工浮島の風波等による影響が大きい方向に抽水植物用の人工浮島を設けた構成を示す説明図である。図6は、岸に向かって打ちつける波浪に対する沈水植物用人工浮島を保護する構成を示す説明図である。
(Embodiment 2)
In the present embodiment, a configuration in which the artificial floating island 10 for a submerged plant and the artificial floating island 60 for a drained plant are juxtaposed will be described. By adopting such a configuration, for example, the effects of wind waves on the planting base 20 of the artificial floating island 10 for submerged plants are further reduced, and the transparency of water is improved by the action of the artificial floating island 60 for extracted plants. It can be made easier to grow. FIG. 5 is an explanatory diagram showing a configuration in which an artificial floating island for a water extraction plant is provided in a direction in which the influence of wind waves or the like of the artificial floating island for a submerged plant is large. FIG. 6 is an explanatory diagram showing a configuration for protecting an artificial floating island for a submerged plant against waves hitting toward the shore.
本実施の形態では、沈水植物用人工浮島10へ打ち寄せる波の高い方には、消波機能物として抽水植物用人工浮島60が設けられている。抽水植物用人工浮島60は、沈水植物用人工浮島10より離されて設けられている。沈水植物用人工浮島10の構成は、前記実施の形態1で説明したと同様に構成されている。   In the present embodiment, an artificial floating island 60 for a water extraction plant is provided as a wave-dissipating function for the higher wave that hits the artificial floating island 10 for a submerged plant. The artificial floating island 60 for the water-drawing plant is provided apart from the artificial floating island 10 for the submerged plant. The structure of the artificial floating island 10 for a submerged plant is the same as that described in the first embodiment.
一方、抽水植物用人工浮島60の構成は、フロート61を用いた浮体構造を有し、フレーム62内に植栽基盤63が設けられている。抽水植物用人工浮島60としては、フレーム式、フレームレス式等のどちらでもよく、植栽基盤63も化学合繊マットやヤシマット等を用いるとよい。かかる植栽基盤63に、例えば、キショウブ等の図4に示した抽水植物が植栽ポッドを介して、あるいは直接植栽されている。根が、植栽基盤20を通して、十分に張られている。   On the other hand, the structure of the artificial floating island 60 for a water extraction plant has a floating structure using a float 61, and a planting base 63 is provided in a frame 62. The artificial floating island 60 for the water extraction plant may be either a frame type or a frameless type, and the planting base 63 may be a chemical synthetic mat or a palm mat. On the planting base 63, for example, the water-drawing plant shown in FIG. 4 such as kishobu is planted via a planting pod or directly. The roots are sufficiently stretched through the planting base 20.
かかる構成では、沈水植物用人工浮島10に打ち寄せる波の高さを、予め設定しておいた沈水植物の生育の限界とする波高を基準として、その沈水植物の生育限界の波高より高いか、あるいは低いかで、その対応を分けている。   In such a configuration, the wave height that strikes the artificial floating island 10 for a submerged plant is higher than the wave height at the growth limit of the submerged plant, based on the wave height that is set as the limit of the growth of the submerged plant that has been set in advance, or The response is divided according to the low.
すなわち、沈水植物が生育することができる限界の波高より高い波が打ち寄せる場合は、その高い波が打ち寄せる方向に、抽水植物用人工浮島60を設置する。抽水植物用人工浮島60は、沈水植物用人工浮島10とは、所定の距離以上離れないようにアンカー等で別々に係留すればよい。   That is, when a wave higher than the limit wave height at which a submerged plant can grow, the artificial floating island 60 for a water extraction plant is installed in the direction in which the high wave hits. The artificial floating island 60 for the water-drawing plant may be moored separately by an anchor or the like so as not to be separated from the artificial floating island 10 for the submerged plant by a predetermined distance or more.
また、沈水植物用人工浮島10に打ち寄せる波が、沈水植物の生育限界の波高より低い場合には、打ち寄せる波の高さの内、最大波高の波の打ち寄せる方向に、抽水植物用人工浮島60を設ければよい。   In addition, when the wave that strikes the artificial floating island 10 for the submerged plant is lower than the wave height of the submerged plant growth limit, the artificial floating island 60 for the drained plant is placed in the direction of the wave of the maximum wave height of the wave to be struck. What is necessary is just to provide.
沈水植物の生育限界の波高は、例えば、一般的に沈水植物の育つ生育限界として、20cmとしておけばよい。さらには、より詳細には、沈水植物毎にかかる生育限界の波高を決めても構わない。現在は、沈水植物の生育限界を示す平均波高を20cmと設定し、20cm以上の場合を設定波高より高い波と、20cm未満の場合を設定波高より低い波とした。   The wave height of the growth limit of a submerged plant may be set to 20 cm, for example, as a growth limit generally for growing a submerged plant. Furthermore, in more detail, you may decide the wave height of the growth limit concerning every submerged plant. At present, the average wave height indicating the growth limit of a submerged plant is set to 20 cm, the wave higher than the set wave height is set to 20 cm or more, and the wave lower than the set wave height is set to less than 20 cm.
また、打ち寄せる波の高さは、現地での実測によればよい。例えば、方向別の波高を計器により計測すればよい。あるいは、方向別に、例えば、年間の風向、風速、吹送距離とから計算して、その波高が沈水植物の生育限界の波高より高いか、低いかで、消波機能物としての抽水植物用人工浮島60の設置方向を決めても構わない。   In addition, the height of the wave that strikes may be based on actual measurements at the site. For example, the wave height for each direction may be measured with a meter. Or, for each direction, for example, calculated from the annual wind direction, wind speed, and blowing distance, and whether the wave height is higher or lower than the wave height of the submerged plant growth limit, the artificial floating island for water extraction plants as a wave-dissipating function The installation direction of 60 may be determined.
併せて、沈水植物用人工浮島10のそばに抽水植物用人工浮島60を設けることで、抽水植物用の浮島の存在により水面下への光の透過を抑え(遮光効果)、植物プランクトンの発生を防止する水質浄化能力によって初期の透明度を増加させ、沈水植物の初期の生育を高めることもできる。   In addition, by providing an artificial floating island 60 for the extraction plant near the artificial floating island 10 for the submerged plant, the presence of the floating island for the extraction plant suppresses the transmission of light below the surface of the water (light-shielding effect), thereby reducing the generation of phytoplankton. The ability to prevent water purification can increase initial transparency and increase the initial growth of submerged plants.
かかる構成では、波風による影響が大きい水域に沈水植物用人工浮島10を設置しても、抽水植物用人工浮島60がかかる波風を直接受けて、沈水植物用人工浮島10への波の影響を少なく抑えることができる。特に、抽水植物の水中に伸張する根によって、水中の表層側の波が抑えられ、かかる消波効果が沈水植物の植栽基盤20に与える影響を軽減し、沈水植物の繁茂を促す。   In such a configuration, even if the artificial floating island 10 for a submerged plant is installed in a water area where the influence of the wave wind is large, the artificial floating island 60 for the submerged plant directly receives the wave wind and the influence of the wave on the artificial floating island 10 for the submerged plant is reduced. Can be suppressed. In particular, the roots that extend into the water of the water extraction plant suppress waves on the surface layer side of the water, reducing the influence of the wave-dissipating effect on the planting base 20 of the submerged plant, and promoting the overgrowth of the submerged plant.
例えば、湾岸等の風波の影響が大きい水域においては、特に有効に機能する。陸に向かって風波が押し寄せる状況下、沈水植物用人工浮島10を囲むように、抽水植物用人工浮島60を配することで、風波の影響を少なくすることができる。   For example, it functions particularly effectively in water areas such as the Gulf that are greatly affected by wind waves. By arranging the artificial floating island 60 for the water-drawn plant so as to surround the artificial floating island 10 for the submerged plant under the situation where the wind waves are rushing toward the land, the influence of the wind wave can be reduced.
また、沈水植物用人工浮島10に所定間隔離して設置される抽水植物用人工浮島60には、遮光、栄養塩類の取り込み、水中に伸張する根に付着する微生物群集による水質浄化、鳥類の休息・営巣の場等々、沈水植物用人工浮島10とは異なる多機能な作用を持っている。そこで、かかる異なる機能を有する沈水植物用人工浮島10、抽水植物用人工浮島60を配置し、二つの浮島を組みあわせることにより、効果的な水質浄化、生態系の創出を行うことができる。   In addition, an artificial floating island 60 for water extraction plants, which is installed on the artificial floating island 10 for submerged plants, is shielded from light, nutrients are taken in, water is purified by microbial communities attached to the roots that extend into the water, and birds rest and It has a multi-functional action different from the artificial floating island 10 for submerged plants, such as a nesting place. Therefore, by arranging the artificial floating island 10 for submerged plants and the artificial floating island 60 for water extraction plants having different functions and combining the two floating islands, effective water purification and creation of an ecosystem can be performed.
すなわち、沈水植物用人工浮島10の周囲に従来の抽水植物用人工浮島60を配置することにより、従来の浮島よりも高い水質浄化能力を持たせることができる。例えば、抽水植物用人工浮島60に生えている抽水植物による遮光効果は、設置初期から効果的に植物プランクトンの増殖を抑え、水の透明度を向上させるため、その分、汚濁の高い水域への沈水植物用人工浮島10の設置可能性を広げられる。   That is, by disposing the conventional artificial floating island 60 for water extraction plants around the artificial floating island 10 for submerged plants, it is possible to have higher water quality purification ability than the conventional floating island. For example, the light-shielding effect of the extraction plant growing on the artificial floating island 60 for the extraction plant effectively suppresses the growth of phytoplankton from the beginning of installation and improves the transparency of the water. The installation possibility of the artificial floating island 10 for plants can be expanded.
また、沈水植物用人工浮島10の周囲に抽水植物用の浮島を配置することにより、沈水植物用人工浮島10のフロート40が人目につきにくくなり、景観を向上する等の付加価値も発生する。特に、風波の方向が一定しない水域の場合には、沈水植物用人工浮島10の周囲を完全に抽水植物用人工浮島60で囲むことが求められるが、かかる際には、その効果が大きい。   In addition, by arranging floating islands for water-drawn plants around the artificial floating island 10 for submerged plants, the float 40 of the artificial floating island 10 for submerged plants is not easily noticeable, and additional values such as improving the landscape are also generated. In particular, in the case of a water area where the direction of the wind wave is not constant, it is required to completely surround the artificial floating island 10 for submerged plants with the artificial floating island 60 for water extraction plants. In such a case, the effect is great.
すなわち、沈水植物用人工浮島10では、沈水植物と共に植栽基盤20は常時水没しているため、フロート40が水面に浮いているだけの状態であるが、抽水植物用人工浮島60等のように植物が生えた状態の浮島があると、水面にフロート40だけが浮いているという味気ない状況が隠され、景観改善が行われて好ましいのである。   That is, in the artificial floating island 10 for a submerged plant, the planting base 20 is always submerged together with the submerged plant, so that the float 40 is only floating on the water surface. If there is a floating island in a state where a plant grows, it is preferable that an unpleasant situation that only the float 40 is floating on the surface of the water is hidden and the landscape is improved.
抽水植物、浮葉植物、沈水植物帯を連続的に設ける植生基盤もしくは浮島の構成が、これまで提案されている。しかし、透明度が低い水質浄化対象水域では、水深の浅い所でしか沈水植物は生育することができず、かかる構成では、沈水植物は抽水植物、浮葉植物の競争に負けて生育することができず、かかる構造は好ましくない。図5に示す如く、別々の浮島とするか、しきりを設ける等の構造とするのが望ましい。   So far, a structure of a vegetation base or a floating island in which water-drawn plants, floating leaf plants, and submerged plant zones are continuously provided has been proposed. However, in water purification target water areas with low transparency, submerged plants can only grow at shallow depths, and in such a configuration, submerged plants cannot grow against the competition of water-blowing and floating leaf plants. Such a structure is not preferred. As shown in FIG. 5, it is desirable to have separate floating islands or a structure such as providing a threshold.
また、風波等が植栽基盤20に与える影響が大きい場所では、消波構造として他にも、沈水植物用人工浮島10の植栽基盤20の周囲にある程度の高さの消波用の壁を設ける構造でも構わない。あるいは、プラスチック製の繊維状の紐状担体に付着性の微生物やワムシ等の原生動物が生息可能な構成を付加したものを、沈水植物用人工浮島10の周辺隣接域に配置して消波効果を確保するようにしても構わない。かかる構成では、紐状担体による水質浄化効果をも合わせて享受できる。   Moreover, in the place where the influence which a wind wave etc. has on the planting base 20 is large, in addition to the wave-dissipating structure, a wall for wave-dissipation of a certain height around the planting base 20 of the submerged plant artificial floating island 10 is provided. The structure to provide may be sufficient. Alternatively, a structure in which a structure in which protozoa such as adherent microorganisms and rotifers can inhabit is added to a plastic fibrous string-like carrier is disposed in the adjacent area around the artificial floating island 10 for submerged plants, and the wave-dissipating effect You may make it secure. In such a configuration, it is possible to enjoy the water purification effect of the string-like carrier.
尚、上記説明では、風波の影響の強い場所に沈水植物用人工浮島10を設置するに際して抽水植物用人工浮島60を離して設ける場合について説明したが、特段風波の影響がないような穏やかな池の水面に沈水植物用人工浮島10を設ける場合には、抽水植物用人工浮島60を沈水植物用人工浮島10と併置させても構わない。例えば、フロート同士を接続させる等して連結し、隣接配置するようにしても構わない。かかる構成では、抽水植物用人工浮島60の機能は、前述の如く、遮光効果等により植物プランクトンの発生をより防止して、沈水植物の生育を促すことにある。勿論、かかる場合に、遮光効果、栄養塩類等の除去効果が得られる範囲内で、沈水植物用人工浮島10と抽水植物用人工浮島60とを離して置いても構わない。   In the above description, the case where the artificial floating island 60 for the water extraction plant is provided separately when the artificial floating island 10 for the submerged plant is installed in a place where the influence of the wind wave is strong is described. When the artificial floating island 10 for a submerged plant is provided on the water surface, the artificial floating island 60 for a submerged plant may be juxtaposed with the artificial floating island 10 for a submerged plant. For example, the floats may be connected to each other and connected adjacently. In such a configuration, the function of the artificial floating island 60 for a water-drawing plant is to further prevent the generation of phytoplankton by the light-shielding effect and promote the growth of submerged plants as described above. Of course, in such a case, the submerged plant artificial floating island 10 and the extraction plant artificial floating island 60 may be separated from each other within a range in which the light shielding effect and the removal effect of nutrients and the like are obtained.
(実施の形態3)
本実施の形態では、前記実施の形態1で述べた沈水植物用人工浮島10の構成を用いて、沈水植物用人工浮島10の設置対象水域に合わせた沈水植物群落の復元を行う方法について述べる。
(Embodiment 3)
In the present embodiment, a method for restoring a submerged plant community according to the installation target water area of the submerged plant artificial floating island 10 using the configuration of the submerged plant artificial floating island 10 described in the first embodiment will be described.
かかる方法では、基本的に、沈水植物の生育可能な光透過率の生育限界水深が、沈水植物の成長により深くなるのに従って、沈水植物が植栽された沈水植物用人工浮島10の沈水植物用の植栽基盤20を生育限界水深の範囲内で漸次深くしていく手法を採用する。   In such a method, basically, as the growth limit water depth of the light transmittance at which the submerged plant can grow becomes deeper as the submerged plant grows, the submerged plant for artificial floating island 10 where the submerged plant is planted is used. A method of gradually deepening the planting base 20 in the range of the growth limit water depth is adopted.
図7(a)はかかる手法について述べたものであるが、設置対象水域として、溜め池Aを想定し、かかる溜め池Aに沈水植物用人工浮島10を設置し、水域に沈水植物の群落を形成する場合を例に挙げて説明する。かかる溜め池Aでは、沈水植物の生育が不可能な程に、水の汚濁が進んでいるものとする。   FIG. 7 (a) describes such a technique. As an installation target water area, a reservoir pond A is assumed, an artificial floating island 10 for a submerged plant is installed in the reservoir pond A, and a submerged plant community is installed in the water area. The case of forming will be described as an example. In such a reservoir pond A, it is assumed that the water is so polluted that it is impossible to grow a submerged plant.
図7(a)に示すように、先ず、設置初期は植栽基盤20の高さを水表面に対する光の透過率が光量子計で20%以上となる範囲の水深に設置する。例えば、透明度が1m程度であれば、20〜30cm程度の水深となる。かかる水深に設置し、沈水植物の生育を促進する。設置当初は、水質汚濁が進行して沈水植物が実質的に絶滅したような水域では、水の透明度が悪く、植栽基盤20を浅く設定しないと、光の透過率が20%以上とならない。   As shown in FIG. 7 (a), first, the height of the planting base 20 is initially set at a water depth in a range where the light transmittance with respect to the water surface is 20% or more by the photon meter. For example, if the transparency is about 1 m, the water depth is about 20 to 30 cm. Install at such depth to promote the growth of submerged plants. At the beginning of installation, in a water area where water pollution has progressed and the submerged plant has been substantially extinct, the transparency of water is poor, and unless the planting base 20 is set shallow, the light transmittance does not reach 20% or more.
より確実に行うには、発芽前や、苗株の茎丈が例えば10cm以下の場合には、光量子計の測定で水面の光の50%以上となる水深を選択して行うのがよい。   In order to carry out more reliably, it is good to carry out by selecting the water depth which becomes 50% or more of the light of a water surface by the measurement of a photon meter before germination or when the stem height of a seedling is 10 cm or less.
かかる状態で沈水植物が植栽基盤20に生育すると、生育した沈水植物により水の透明度が少しずつ改善されてくる。沈水植物が繁茂するにつれ、その水質浄化作用で透明度が増加し、光の透過率も向上する。その結果、沈水植物の生育可能な生育限界水深が深くなり、植栽基盤20の設置可能水深もそれに合わせて深くすることができる。   When a submerged plant grows on the planting base 20 in such a state, the transparency of water is gradually improved by the grown submerged plant. As submerged plants grow, their water purification improves transparency and improves light transmission. As a result, the growth limit water depth at which the submerged plant can grow is deepened, and the water depth at which the planting base 20 can be installed can be deepened accordingly.
このように沈水植物の生育に合わせて、アングル33、34を調節することで、植栽基盤20の設置水深を深くする。植栽基盤20の設置水深を調節していくことにより、沈水植物群落の茎高を増大し、繁茂させていくのである。例えば、生育により茎丈が10cmより大きくなった場合には、水面の光に対する透過率が20%以上となる範囲で水深を深くして行く。例えば、光の透過率が20%の水深に設置する。   Thus, the installation water depth of the planting base 20 is deepened by adjusting the angles 33 and 34 according to the growth of the submerged plant. By adjusting the installation water depth of the planting base 20, the height of the stem of the submerged plant community is increased and the plant grows. For example, when the stem height is larger than 10 cm due to growth, the water depth is increased in a range where the transmittance of light on the water surface is 20% or more. For example, it is installed at a water depth where the light transmittance is 20%.
このようにして沈水植物がさらに繁茂し、対象水域の水質浄化が行われて、漸次水の透明度が改善されて行く。それに合わせて植栽基盤20の設置水深を深くして行くと、対象水域の湖底に沈水植物の繁茂が可能となる光を透過することができるようになる。かかる水深の変更は、例えば、年に1回、水が一番濁り易い時期、夏等に、光量子が20%となる水深に植栽基盤20の水深を下げてやればよい。   In this way, the submerged plant grows further, the water quality of the target water area is purified, and the transparency of the water is gradually improved. If the installation water depth of the planting base 20 is deepened according to it, the light which enables the submerged plant to grow can be transmitted to the bottom of the lake in the target water area. Such a change in water depth may be achieved by, for example, lowering the water depth of the planting base 20 once a year to a water depth at which the photon is 20% in the summer when the water is most turbid.
かかる状態で、沈水植物用の植栽基盤20に植栽された沈水植物の種子あるいは胞子が水底に飛散する。沈水植物用人工浮島10内の繁茂した沈水植物群落から種子や胞子が、周辺水域に供給されると、沈水植物用人工浮島10の周辺の水底から沈水植物群落が徐々に形成されてゆくこととなる。沈水域の生態系機能の回復により水質浄化が加速し、最終的には水域全体が浄化され、沈水植物群落についても水底に確実に形成されることとなる。かかる様子を、図7(b)に模式的に示した。   In this state, the seeds or spores of the submerged plant planted on the planting base 20 for the submerged plant scatter to the bottom of the water. When seeds and spores are supplied to the surrounding water area from the overgrown submerged plant community in the submerged plant floating island 10, the submerged plant community is gradually formed from the bottom of the submerged plant artificial floating island 10. Become. The restoration of ecosystem functions in submerged areas will accelerate water purification, eventually purifying the entire water area and ensuring that submerged plant communities are also formed at the bottom of the water. Such a state is schematically shown in FIG.
飛散した種子あるいは胞子に基づき水底に沈水植物を生やすことが確実に行われるようになった時点で、図7(c)に示すように、例えば、沈水植物用人工浮島10を、撤去すればよい。周囲景観の観点からも撤去が好ましい。   When the submerged plant is reliably grown on the bottom of the water based on the scattered seeds or spores, as shown in FIG. 7C, for example, the artificial floating island 10 for the submerged plant may be removed. . Removal is also preferable from the viewpoint of the surrounding landscape.
沈水植物用人工浮島10の植栽基盤20に設置対象水域の水底から採取した土砂を充填する場合には、かかる土砂に埋まっていた種子等が発芽して、その設置対象水域に以前存在していた沈水植物が生育することとなり、沈水植物群落の復元ができる。また、埋まっていた種子等が少ない場合には、かかる水底から採取した土砂からあらかじめ発芽、育成して、苗株を増やした上で、その苗株を用いることによりその水域に生息していた在来の沈水植物群落を水域に復元することもできる。   When filling the planting base 20 of the artificial floating island 10 for submerged plants with the earth and sand collected from the bottom of the target water area, the seeds buried in the earth and sand have germinated and previously existed in the target water area. The submerged plant grows and the submerged plant community can be restored. In addition, if there are few seeds etc. buried, germinate and grow in advance from the sediment collected from the bottom of the water, increase the seedlings, and then use the seedlings to inhabit the waters. It is possible to restore the existing submerged plant community to the water area.
水質汚濁の進行した水域に浄化目的で沈水植物用の浮島を設置する際は、浮島の設置面積を、水面積に対して2割以上とする。一般的に、湖沼の沿岸域の沈水植物群落が2割復元すると、透明度が1m弱の水域では透明度は2m程度になると言われ、かなりの程度の透明度の改善効果がある。例えば、20%以上の透過率が確保される水深は0.7mから1.4mとなり、水深1.4mの水底まで沈水植物群落の復元が可能となる。   When installing floating islands for submerged plants in water areas where water pollution has progressed for purification purposes, the installation area of floating islands shall be 20% or more of the water area. Generally, when 20% of submerged plant communities in the coastal areas of lakes and marshes are restored, it is said that the transparency is about 2m in water areas with transparency of less than 1m, which has a considerable degree of transparency improvement effect. For example, the water depth at which a transmittance of 20% or more is ensured is 0.7 m to 1.4 m, and the submerged plant community can be restored to the bottom of the water depth of 1.4 m.
(実施の形態4)
本実施の形態では、前記実施の形態1で説明した沈水植物用人工浮島10を用いて、動物プランクトンの密度、種類数が非常に少ないか、または小型の動物プランクトン群集しか存在しない水域において、沈水植物用人工浮島10による水質浄化機能を高める方法について説明する。
(Embodiment 4)
In the present embodiment, using the artificial floating island 10 for a submerged plant described in the first embodiment, submergence is performed in a water area where the density and number of types of zooplankton are very small or only small zooplankton communities exist. A method of enhancing the water purification function by the plant artificial floating island 10 will be described.
前記実施の形態で説明したように沈水植物用人工浮島10の植栽基盤20を使用して、適切に沈水植物を繁茂させる。このように沈水植物群落を繁茂させた後、図8に示すように、カブトミジンコ、オカメミジンコ、ケンミジンコ、ゾウミジンコ等のミジンコ類、カイアシ類、ワムシ類等の動物プランクトンを投入する。   As described in the above embodiment, the submerged plant is appropriately grown using the planting base 20 of the artificial floating island 10 for a submerged plant. After the submerged plant community has grown in this way, as shown in FIG. 8, zooplankton such as Daphnia magna, Okame Daphnia, Ken Daphnia, Elephant Daphnia, etc., copepods, rotifers, etc. are introduced.
投入する動物プランクトンは、単一種類でもよいが、これらの動物プランクトンの群集を混合して投入する方が、様々な植物プランクトンに対して効果があるので望ましい。投入する動物プランクトンの収集方法は、培養しても良いし、対象水域の流域の動物プランクトン群集が豊富な池や沼においては、動物プランクトン用のネットで捕集することで高密度に収集することができる。   The zooplankton to be introduced may be of a single type, but it is desirable to mix and introduce these zooplankton communities because they are effective against various phytoplankton. The zooplankton can be collected by culturing, or in ponds and swamps where zooplankton communities are abundant in the target water basin, collect them by collecting them with a net for zooplankton. Can do.
特に、本発明では、前記実施の形態1で述べたように、沈水植物用人工浮島10の植栽基盤20の水没部分には、ネット51が張られているので、かかる動物プランクトンを餌とする魚等が入り込むことがない。そのため、投入した動物プランクトンは、沈水植物用人工浮島10の沈水植物内で生息し、増えることができる。   In particular, in the present invention, as described in the first embodiment, since the net 51 is stretched on the submerged portion of the planting base 20 of the submerged artificial floating island 10, such zooplankton is used as a bait. Fish etc. will not enter. Therefore, the introduced zooplankton can inhabit and increase in the submerged plant of the submerged plant artificial floating island 10.
ミジンコの中でも、ゾウミジンコ(0.5mm)、ニセミジンコ(0.2〜0.5mm)、マルミジンコ(0.5mm)等の小型のミジンコに対して、大型のミジンコであるカブトミジンコ(0.6〜2mm)、ミジンコ(ダフニア:0.7〜3mm)、オカメミジンコ(成体の体長が2mm)等の場合には、小型のミジンコよりも様々な植物プランクトンを沢山食べて、水質浄化効率が高いことが知られている。   Among Daphnia magna (0.5 mm), Niseko (0.2-0.5 mm), Marsh (0.5 mm) and other small Daphnia, butterfly (0.6- 2 mm), Daphnia (daphnia: 0.7 to 3 mm), and giant sea bream (adult body length is 2 mm), etc., eat more phytoplankton than small daphnia and have high water purification efficiency. Are known.
かかる大型のミジンコは、沈水植物が繁茂した隠れ家がないと、成体の体長が1〜2mmと大きくなるので、目立って魚に捕食され易い。しかし、本発明の沈水植物用人工浮島10では、ネット51でかかる魚の侵入を防止して、大型のミジンコの捕食が行われない。実際に、沈水植物等の水草の少ない水域では、大型のミジンコは少なく、ミジンコを外部から投入することの効果は大きいと言える。   If there is no hideout where the submerged plant is prosperous, such a large Daphnia will be noticeably easily preyed by fish because the adult body length will be as large as 1 to 2 mm. However, in the artificial floating island 10 for a submerged plant of the present invention, the net 51 prevents the fish from entering, and large daphnia is not preyed. Actually, there are few large daphnias in water areas with few aquatic plants such as submerged plants, and it can be said that the effect of introducing daphnia from the outside is great.
また、ミジンコは水温の低下、餌環境の悪化等の環境条件の変化により耐久卵(休眠卵)を湖底に沈め、環境条件が好転したときにそれらの卵から発生してくることが知られている。かかる現象を利用して、まず対象水域の水底を採取し、魚のいない条件で湖底に眠っている動物プランクトンの耐久卵からミジンコを発生させ、増殖させる。それを沈水植物用人工浮島10内に繁茂した沈水植物群落に投入することで、他水域からの種の移入を防止し、在来の動物プランクトン群集を利用して浄化することができる。   Daphnia is known to be generated from eggs when the environmental conditions are improved by submerging durable eggs (dormant eggs) on the bottom of the lake due to changes in environmental conditions such as a drop in water temperature and a deterioration in the feeding environment. Yes. Taking advantage of this phenomenon, the bottom of the target water area is first collected, and daphnia are generated from the endangered eggs of zooplankton sleeping on the bottom of the lake under the condition of no fish. By introducing it into a submerged plant community that proliferated in the artificial floating island 10 for submerged plants, it is possible to prevent the introduction of species from other water areas and to purify it using the conventional zooplankton community.
アオコの形成の主な種となって発生する藍藻類のミクロキスティスを培養したものに、水底から採取した泥を投入した実験の結果を図9(a)に示す。実験は28℃、光量は2000ルクスで、12時間ごとに明暗条件を変化させ、ゆっくりと攪拌しながら行った。水底から動物プランクトン群集が発生し、14日後には植物プランクトンが動物プランクトンに捕食された。その結果、植物プランクトンの現存量の指標であるクロロフィルa濃度が大きく減少し、水が透明となることが確認された。   FIG. 9 (a) shows the result of an experiment in which mud collected from the bottom of the water is introduced into a culture of the blue-green algae microkistis that is the main species of the formation of blue sea bream. The experiment was performed at 28 ° C. and a light intensity of 2000 lux while changing the light and dark conditions every 12 hours and slowly stirring. A zooplankton community emerged from the bottom of the water, and 14 days later, the phytoplankton was preyed by the zooplankton. As a result, it was confirmed that the concentration of chlorophyll a, which is an indicator of the existing amount of phytoplankton, was greatly reduced and the water became transparent.
動物プランクトンの有無の違いで、水の透明度に関わる植物プランクトンの増加が影響を受けることが分かる。因みに、白抜きの場合は動物プランクトンが無い場合を示し、黒塗りの場合は動物プランクトンがある場合を示した。また、それぞれ3種の試験体を用いて行い、その結果を△、□、〇で示した。   It can be seen that the increase in phytoplankton related to water transparency is affected by the presence or absence of zooplankton. By the way, the case where there is no zooplankton is shown in white, and the case where there is zooplankton is shown in black. Moreover, it carried out using 3 types of each test body, and the result was shown by (triangle | delta), (square), and (circle).
また、動物プランクトンの個体数、種類数が少なく、アオコ(主に藍藻のミクロキスティス)が大量に発生している実際の池の水を採取し、池の泥を投入、魚が存在しない条件で実験を行った。25℃、2000ルクスの12時間の明暗条件の変換で18日間培養を行った。動物プランクトンはほとんど発生せず、植物プランクトンは減少しなかった。しかし、図9(b)に示すように、18日後に、動物プランクトンが豊富な池からプランクトンネットによりワムシやミジンコ等を含む動物プランクトン群集を捕集し、投入したところたちどころにアオコが消失し、透明度も改善され、クロロフィルa濃度が著しく減少した。   In addition, the number of individuals and types of zooplankton is small, the water of the actual pond with a large amount of blue-tailed sea cucumber (mainly the blue-green algae Microkistis) is collected, the pond mud is thrown in, and no fish exist. The experiment was conducted. Culturing was carried out for 18 days under conversion of light and dark conditions at 25 ° C. and 2000 lux for 12 hours. Little zooplankton occurred and phytoplankton did not decrease. However, as shown in Fig. 9 (b), 18 days later, zooplankton communities including rotifers and daphnids were collected from the ponds rich in zooplankton by the plankton net, and the ako disappeared as soon as it was introduced. Transparency was also improved and chlorophyll a concentration was significantly reduced.
かかる実験結果により、動物プランクトン群集の少ない水域においても、耐久卵が水底に存在する場合はそこから発生、培養した動物プランクトン群集を、再生した沈水植物の群落の中に投入し生息させることで、水質の浄化作用が促進、改善されることが分かる。   As a result of this experiment, even in a water area with a small amount of zooplankton community, if a durable egg is present on the bottom of the water, the cultured zooplankton community is put into a regenerated submerged plant community and inhabited. It can be seen that the water purification effect is promoted and improved.
また、耐久卵がない場合でも、図9(b)に示す如く、培養もしくは近くの動物プランクトンが豊富に存在する水域から捕集したものを、魚類の防止策を講じてある沈水植物用人工浮島10に投入する手法により、沈水植物群落内で増加させることができ、植物プランクトンを効果的に除去することができる。   In addition, even when there is no durable egg, as shown in FIG. 9 (b), an artificial floating island for a submerged plant that has been collected from a water area where culture or nearby zooplankton is abundant has been taken. 10 can be increased in a submerged plant community, and phytoplankton can be effectively removed.
以上、本発明者によってなされた発明を実施の形態に基づき具体的に説明したが、本発明は前記実施の形態に限定されるものではなく、その要旨を逸脱しない範囲で種々変更可能であることはいうまでもない。   As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.
本発明の沈水植物を人工的に植栽した沈水植物用人工浮島に関連した分野で有効に利用することができる。   The present invention can be effectively used in a field related to an artificial floating island for a submerged plant in which the submerged plant of the present invention is artificially planted.
本発明の一実施の形態の沈水植物用人工浮島の実施例を模式的の示す側面図である。It is a side view which shows typically the Example of the artificial floating island for submerged plants of one embodiment of this invention. (a)は本発明で使用するフロートとそのフレームの構成を示す斜視図であり、(b)はフレーム内に植栽基盤を設けた状況を示す斜視図である。(A) is a perspective view which shows the structure of the float used in this invention, and its flame | frame, (b) is a perspective view which shows the condition which provided the planting base in the flame | frame. (a)、(b)は、水位調整を行う状況を示す説明図である。(A), (b) is explanatory drawing which shows the condition which performs water level adjustment. 沈水植物等の水生植物の具体例を一覧にして示した説明図である。It is explanatory drawing which showed and listed the specific example of aquatic plants, such as a submerged plant. 沈水植物用人工浮島の風上側に抽水植物用人工浮島を設けた構成を示す説明図である。It is explanatory drawing which shows the structure which provided the artificial floating island for water extraction plants in the windward side of the artificial floating island for submerged plants. 岸に沿って沈水植物用人工浮島と抽水植物用人工浮島とを配置した様子を示す説明図である。It is explanatory drawing which shows a mode that the artificial floating island for submerged plants and the artificial floating island for water extraction plants were arrange | positioned along the shore. (a)、(b)、(c)は、沈水植物用人工浮島を用いた沈水植物群落の復元方法の手順を示す説明図である。(A), (b), (c) is explanatory drawing which shows the procedure of the restoration method of a submerged plant community using the artificial floating island for submerged plants. 沈水植物用人工浮島に動物プランクトンを投入して水質改善の促進を行う説明図である。It is explanatory drawing which introduces zooplankton to the artificial floating island for submerged plants, and promotes water quality improvement. (a)は動物プランクトンの有無による水質改善の様子を示す説明図であり、(b)は動物プランクトンを投入することで水質改善が図れることを示す説明図である。(A) is explanatory drawing which shows the mode of water quality improvement by the presence or absence of zooplankton, (b) is explanatory drawing which shows that water quality improvement can be aimed at by throwing in zooplankton.
符号の説明Explanation of symbols
10 沈水植物用人工浮島
20 植栽基盤
20a 多孔質部材
21 植栽ポッド
30 支持体
31 フレーム
31a アングル
32 シート
32a ブルーシート
33 アングル
34 アングル
35 ボルト
40 フロート
51 ネット
52 ネット
60 抽水植物用人工浮島
61 フロート
62 フレーム
63 植栽基盤
A 溜め池
DESCRIPTION OF SYMBOLS 10 Artificial floating island for submerged plants 20 Planting base 20a Porous member 21 Planting pod 30 Support body 31 Frame 31a Angle 32 Sheet 32a Blue sheet 33 Angle 34 Angle 35 Bolt 40 Float 51 Net 52 Net 60 Artificial floating island 61 62 Frame 63 Planting base A Reservoir

Claims (1)

  1. 沈水植物の生育可能な光透過率の生育限界水深が前記沈水植物の成長により深くなるのに従って、前記沈水植物が植栽された沈水植物用人工浮島の植栽基盤を前記限界水深の範囲内で深くするステップと、
    前記植栽基盤に植栽された沈水植物の種子あるいは胞子を水底に飛散させるステップと、
    前記飛散した種子あるいは胞子に基づき前記水底に沈水植物を生やすステップとを有し、
    前記沈水植物用人工浮島は、沈水植物が前記水底に根付いた時点で撤去することを特徴とする沈水植物用人工浮島を用いた沈水植物群の形成方法。
    As the growth limit water depth of the light transmittance capable of growing the submerged plant becomes deeper as the submerged plant grows, the planting base of the artificial floating island for submerged plant in which the submerged plant is planted is within the range of the limit water depth. Deepening steps,
    Scattering seeds or spores of submerged plants planted on the planting base to the bottom of the water;
    And growing a submerged plant on the bottom of the water based on the scattered seeds or spores,
    The method for forming a submerged plant group using the submerged plant artificial floating island, wherein the submerged plant artificial floating island is removed when the submerged plant takes root on the bottom of the water.
JP2005220722A 2005-07-29 2005-07-29 Formation method of submerged plant group using artificial floating island for submerged plant Active JP4217232B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2005220722A JP4217232B2 (en) 2005-07-29 2005-07-29 Formation method of submerged plant group using artificial floating island for submerged plant

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2005220722A JP4217232B2 (en) 2005-07-29 2005-07-29 Formation method of submerged plant group using artificial floating island for submerged plant

Related Child Applications (1)

Application Number Title Priority Date Filing Date
JP2008213579A Division JP2008271989A (en) 2008-08-22 2008-08-22 Method for forming submerged plant cluster by using artificial floating island for submerged plant

Publications (2)

Publication Number Publication Date
JP2007029058A JP2007029058A (en) 2007-02-08
JP4217232B2 true JP4217232B2 (en) 2009-01-28

Family

ID=37789052

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2005220722A Active JP4217232B2 (en) 2005-07-29 2005-07-29 Formation method of submerged plant group using artificial floating island for submerged plant

Country Status (1)

Country Link
JP (1) JP4217232B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103749145A (en) * 2014-02-10 2014-04-30 天津市水利科学研究院 Submerged plant modularized growth bed and method for recovering growth of underwater submerged plant
CN106069281A (en) * 2016-06-24 2016-11-09 宁波市农业科学研究院 A kind of submerged plant planting system and method
CN107673478A (en) * 2017-10-31 2018-02-09 中冶华天工程技术有限公司 A kind of restoration methods of the changeable waters submerged plant of lake hydrological

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009061391A (en) * 2007-09-06 2009-03-26 Tadayuki Genchiyou Water quality improvement method of city water
JP5345375B2 (en) * 2008-12-01 2013-11-20 株式会社フジタ How to regenerate a submerged plant, how to cultivate a submerged plant used for it, plant regeneration base, floating island
JP4855503B2 (en) * 2009-07-21 2012-01-18 パシフィックコンサルタンツ株式会社 Vegetation base for artificial floating island, its manufacturing method and artificial floating island for vegetation
CN102161531A (en) * 2011-06-02 2011-08-24 南京师范大学 Device for purifying eutrophic water body
CN102349401B (en) * 2011-06-22 2013-07-10 上海太和水环境科技发展有限公司 Underwater impending planting method for waterweed and waterweed suspension bed device in underwater ecological restoration
CN102415257A (en) * 2011-09-19 2012-04-18 上海水生环境工程有限公司 Mode for planting submerged plant under guidance of biological base net
CN103975746B (en) * 2014-01-21 2016-06-29 大理福娟花卉有限公司 A kind of Photinia glomerata water floatation seedling method
CN104012389B (en) * 2014-06-20 2016-05-11 宝金安 A kind of Paris polyphylla float seedling method
CN104843869B (en) * 2015-05-22 2017-05-17 浙江海洋学院 Tail water floating condition treatment laminate forming device
CN105776557B (en) * 2016-04-25 2019-06-04 江苏江达生态科技有限公司 A kind of nutrition enriched shallow lake Submerged plant communities method for reconstructing

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103749145A (en) * 2014-02-10 2014-04-30 天津市水利科学研究院 Submerged plant modularized growth bed and method for recovering growth of underwater submerged plant
CN103749145B (en) * 2014-02-10 2016-01-20 天津市水利科学研究院 Submerged plant modularization is growth bed and recover the method for water-bed submerged plant growth
CN106069281A (en) * 2016-06-24 2016-11-09 宁波市农业科学研究院 A kind of submerged plant planting system and method
CN107673478A (en) * 2017-10-31 2018-02-09 中冶华天工程技术有限公司 A kind of restoration methods of the changeable waters submerged plant of lake hydrological

Also Published As

Publication number Publication date
JP2007029058A (en) 2007-02-08

Similar Documents

Publication Publication Date Title
JP4217232B2 (en) Formation method of submerged plant group using artificial floating island for submerged plant
CN102106315B (en) Method for cultivating sipunculus nudus in pond
CN104108797A (en) Water body purification system formed by stereoscopic configuration of aquatic animals and plants and purification method thereof
CN203999152U (en) A kind of water body purification system by aquatic animals and plants stereoscopic configurations
JP2008061509A (en) Apparatus for forming seaweed bed and method for forming sea weed bed using the same
JP2006000022A (en) Various kinds water weeds-culturing type fish reef
John et al. The fish grazing of rocky shore algae in the Gulf of Guinea
JP5345375B2 (en) How to regenerate a submerged plant, how to cultivate a submerged plant used for it, plant regeneration base, floating island
JP2008271989A (en) Method for forming submerged plant cluster by using artificial floating island for submerged plant
JP5507347B2 (en) Water purification method for closed waters
KR100958933B1 (en) Spontaneous restoring equipment for kaloula
KR20150048372A (en) Afforestation methods and devices that expand vegetation to lake surfaces to prevent algal blooms
JP2002330651A (en) Method for creating seaweed bed, and net for growing seaweed
JP2002171854A (en) Method and tool for raising perennial marine alga
James Lakshadweep: Islands of ecological fragility, environmental sensitivity and anthropogenic vulnerability
JP4358833B2 (en) Planting base
KR101809351B1 (en) Mass production method of sinonovacula constricta's artificial seeds
CN108793413A (en) Nearshore waters ecological restoring method
KR101190251B1 (en) Method for constructing zostera forest using wood boxes
JP4566145B2 (en) Artificial tidal flats and methods for forming biological habitats on artificial tidal flats
CN212212242U (en) Marine floated eel grass does not have soil and transplants device
KR100374747B1 (en) an artificial water grass of lope type for bringing up a bio resources rearing and that is used to purify method of the quality of water
Krishnamurthy et al. HU~~ N'S IMPACTS ON THE PICHAVARAM MANGROVE ECOSYSTEM: ACASE STUDY FROM SOUTHERN INDIA
KR102200440B1 (en) Aestivating apparatus for sea cucumber
KR20190001835A (en) Induction method for attachment of seaweed leaf

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20071026

A871 Explanation of circumstances concerning accelerated examination

Free format text: JAPANESE INTERMEDIATE CODE: A871

Effective date: 20071121

A975 Report on accelerated examination

Free format text: JAPANESE INTERMEDIATE CODE: A971005

Effective date: 20071221

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20080108

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20080307

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20080624

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20080822

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: 20081028

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: 20081107

R150 Certificate of patent or registration of utility model

Ref document number: 4217232

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111114

Year of fee payment: 3

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121114

Year of fee payment: 4

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20131114

Year of fee payment: 5

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

S531 Written request for registration of change of domicile

Free format text: JAPANESE INTERMEDIATE CODE: R313531

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

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