The Experts below are selected from a list of 69 Experts worldwide ranked by ideXlab platform
Masafumi Saito - One of the best experts on this subject based on the ideXlab platform.
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new type units for artificial reef development of eco friendly artificial reefs and the effectiveness thereof
30th PIANC-AIPCN Congress 2002, 2002Co-Authors: Norikazu Hirose, Akira Watanuki, Masafumi SaitoAbstract:New type units named Aquareef have been developed to act as an artificial reef. The new units when in place have not only excellent stability and good wave dissipation function but also include large complex spaces. These empty spaces act to allow solar light to penetrate through onto the gravel mound below to offer a good seaweed environment. We looked into the hydraulic properties of the unit type-artificial reef using varied hydraulic model tests. We also investigated the biological functions through investigation of biota. Hydraulic model tests as to transmitted wave height, the character of wave force and sliding of the artificial reef body were performed. Charts were produced to provide for the number of rows of units decided by transmitted waves and decisions on stability as part of a design method. The wave transmission coefficient was almost the same as in the hydraulic model tests. In the attached organisms investigation, Laminaria angustata and Alaria crassifolia dominated on units and seaweed were observed on the rubble. Standing crops of seaweed on units were 27 times that for normal foot protection blocks. This site is in a barren ground region of the Japan Sea in Hokkaido. 2 years after construction, Sargassum patens and Laminaria ochotensis were seem in abundance. 2 years after construction, a two layer zonation provided a habitat for such as Pachymeniopsis lanceolata on the upper zone and Ulva pertusa on the lower zone of the units dominating. Crassostrea nipponica attached to the whole unit and abalone attached from the rubble area under one unit to the lower zone of the unit. Ecklonia cava was observed on the rubble and inside the unit while Sargassum sp. was observed on the flat phase of the lower zone of the unit. Acamthopagrus schlegeli and Girella punctata were observed to shoal around the unit.
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new type units for artificial reef development of eco friendly artificial reefs and the effectiveness thereof
30th PIANC-AIPCN Congress 2002, 2002Co-Authors: Norikazu Hirose, Akira Watanuki, Masafumi SaitoAbstract:New type units named Aquareef have been developed to act as an artificial reef. The new units when in place have not only excellent stability and good wave dissipation function but also include large complex spaces. These empty spaces act to allow solar light to penetrate through onto the gravel mound below to offer a good seaweed environment. We looked into the hydraulic properties of the unit type-artificial reef using varied hydraulic model tests. We also investigated the biological functions through investigation of biota. Hydraulic model tests as to transmitted wave height, the character of wave force and sliding of the artificial reef body were performed. Charts were produced to provide for the number of rows of units decided by transmitted waves and decisions on stability as part of a design method. The wave transmission coefficient was almost the same as in the hydraulic model tests. In the attached organisms investigation, Laminaria angustata and Alaria crassifolia dominated on units and seaweed were observed on the rubble. Standing crops of seaweed on units were 27 times that for normal foot protection blocks. This site is in a barren ground region of the Japan Sea in Hokkaido. 2 years after construction, Sargassum patens and Laminaria ochotensis were seem in abundance. 2 years after construction, a two layer zonation provided a habitat for such as Pachymeniopsis lanceolata on the upper zone and Ulva pertusa on the lower zone of the units dominating. Crassostrea nipponica attached to the whole unit and abalone attached from the rubble area under one unit to the lower zone of the unit. Ecklonia cava was observed on the rubble and inside the unit while Sargassum sp. was observed on the flat phase of the lower zone of the unit. Acamthopagrus schlegeli and Girella punctata were observed to shoal around the unit.
Norikazu Hirose - One of the best experts on this subject based on the ideXlab platform.
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new type units for artificial reef development of eco friendly artificial reefs and the effectiveness thereof
30th PIANC-AIPCN Congress 2002, 2002Co-Authors: Norikazu Hirose, Akira Watanuki, Masafumi SaitoAbstract:New type units named Aquareef have been developed to act as an artificial reef. The new units when in place have not only excellent stability and good wave dissipation function but also include large complex spaces. These empty spaces act to allow solar light to penetrate through onto the gravel mound below to offer a good seaweed environment. We looked into the hydraulic properties of the unit type-artificial reef using varied hydraulic model tests. We also investigated the biological functions through investigation of biota. Hydraulic model tests as to transmitted wave height, the character of wave force and sliding of the artificial reef body were performed. Charts were produced to provide for the number of rows of units decided by transmitted waves and decisions on stability as part of a design method. The wave transmission coefficient was almost the same as in the hydraulic model tests. In the attached organisms investigation, Laminaria angustata and Alaria crassifolia dominated on units and seaweed were observed on the rubble. Standing crops of seaweed on units were 27 times that for normal foot protection blocks. This site is in a barren ground region of the Japan Sea in Hokkaido. 2 years after construction, Sargassum patens and Laminaria ochotensis were seem in abundance. 2 years after construction, a two layer zonation provided a habitat for such as Pachymeniopsis lanceolata on the upper zone and Ulva pertusa on the lower zone of the units dominating. Crassostrea nipponica attached to the whole unit and abalone attached from the rubble area under one unit to the lower zone of the unit. Ecklonia cava was observed on the rubble and inside the unit while Sargassum sp. was observed on the flat phase of the lower zone of the unit. Acamthopagrus schlegeli and Girella punctata were observed to shoal around the unit.
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new type units for artificial reef development of eco friendly artificial reefs and the effectiveness thereof
30th PIANC-AIPCN Congress 2002, 2002Co-Authors: Norikazu Hirose, Akira Watanuki, Masafumi SaitoAbstract:New type units named Aquareef have been developed to act as an artificial reef. The new units when in place have not only excellent stability and good wave dissipation function but also include large complex spaces. These empty spaces act to allow solar light to penetrate through onto the gravel mound below to offer a good seaweed environment. We looked into the hydraulic properties of the unit type-artificial reef using varied hydraulic model tests. We also investigated the biological functions through investigation of biota. Hydraulic model tests as to transmitted wave height, the character of wave force and sliding of the artificial reef body were performed. Charts were produced to provide for the number of rows of units decided by transmitted waves and decisions on stability as part of a design method. The wave transmission coefficient was almost the same as in the hydraulic model tests. In the attached organisms investigation, Laminaria angustata and Alaria crassifolia dominated on units and seaweed were observed on the rubble. Standing crops of seaweed on units were 27 times that for normal foot protection blocks. This site is in a barren ground region of the Japan Sea in Hokkaido. 2 years after construction, Sargassum patens and Laminaria ochotensis were seem in abundance. 2 years after construction, a two layer zonation provided a habitat for such as Pachymeniopsis lanceolata on the upper zone and Ulva pertusa on the lower zone of the units dominating. Crassostrea nipponica attached to the whole unit and abalone attached from the rubble area under one unit to the lower zone of the unit. Ecklonia cava was observed on the rubble and inside the unit while Sargassum sp. was observed on the flat phase of the lower zone of the unit. Acamthopagrus schlegeli and Girella punctata were observed to shoal around the unit.
Akira Watanuki - One of the best experts on this subject based on the ideXlab platform.
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new type units for artificial reef development of eco friendly artificial reefs and the effectiveness thereof
30th PIANC-AIPCN Congress 2002, 2002Co-Authors: Norikazu Hirose, Akira Watanuki, Masafumi SaitoAbstract:New type units named Aquareef have been developed to act as an artificial reef. The new units when in place have not only excellent stability and good wave dissipation function but also include large complex spaces. These empty spaces act to allow solar light to penetrate through onto the gravel mound below to offer a good seaweed environment. We looked into the hydraulic properties of the unit type-artificial reef using varied hydraulic model tests. We also investigated the biological functions through investigation of biota. Hydraulic model tests as to transmitted wave height, the character of wave force and sliding of the artificial reef body were performed. Charts were produced to provide for the number of rows of units decided by transmitted waves and decisions on stability as part of a design method. The wave transmission coefficient was almost the same as in the hydraulic model tests. In the attached organisms investigation, Laminaria angustata and Alaria crassifolia dominated on units and seaweed were observed on the rubble. Standing crops of seaweed on units were 27 times that for normal foot protection blocks. This site is in a barren ground region of the Japan Sea in Hokkaido. 2 years after construction, Sargassum patens and Laminaria ochotensis were seem in abundance. 2 years after construction, a two layer zonation provided a habitat for such as Pachymeniopsis lanceolata on the upper zone and Ulva pertusa on the lower zone of the units dominating. Crassostrea nipponica attached to the whole unit and abalone attached from the rubble area under one unit to the lower zone of the unit. Ecklonia cava was observed on the rubble and inside the unit while Sargassum sp. was observed on the flat phase of the lower zone of the unit. Acamthopagrus schlegeli and Girella punctata were observed to shoal around the unit.
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new type units for artificial reef development of eco friendly artificial reefs and the effectiveness thereof
30th PIANC-AIPCN Congress 2002, 2002Co-Authors: Norikazu Hirose, Akira Watanuki, Masafumi SaitoAbstract:New type units named Aquareef have been developed to act as an artificial reef. The new units when in place have not only excellent stability and good wave dissipation function but also include large complex spaces. These empty spaces act to allow solar light to penetrate through onto the gravel mound below to offer a good seaweed environment. We looked into the hydraulic properties of the unit type-artificial reef using varied hydraulic model tests. We also investigated the biological functions through investigation of biota. Hydraulic model tests as to transmitted wave height, the character of wave force and sliding of the artificial reef body were performed. Charts were produced to provide for the number of rows of units decided by transmitted waves and decisions on stability as part of a design method. The wave transmission coefficient was almost the same as in the hydraulic model tests. In the attached organisms investigation, Laminaria angustata and Alaria crassifolia dominated on units and seaweed were observed on the rubble. Standing crops of seaweed on units were 27 times that for normal foot protection blocks. This site is in a barren ground region of the Japan Sea in Hokkaido. 2 years after construction, Sargassum patens and Laminaria ochotensis were seem in abundance. 2 years after construction, a two layer zonation provided a habitat for such as Pachymeniopsis lanceolata on the upper zone and Ulva pertusa on the lower zone of the units dominating. Crassostrea nipponica attached to the whole unit and abalone attached from the rubble area under one unit to the lower zone of the unit. Ecklonia cava was observed on the rubble and inside the unit while Sargassum sp. was observed on the flat phase of the lower zone of the unit. Acamthopagrus schlegeli and Girella punctata were observed to shoal around the unit.
Hiroyuki Mizuta - One of the best experts on this subject based on the ideXlab platform.
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Nutrient requirement for zoospore formation in two Alariaceous plants Undaria pinnatifida (Harvey) Suringar and Alaria crassifolia Kjellman (Phaeophyceae: Laminariales)
Fisheries Science, 2006Co-Authors: Takeshi Kumura, Hajime Yasui, Hiroyuki MizutaAbstract:Sporophyll formation in two Alariaceous plants, Undaria pinnatifida and Alaria crassifolia, was studied in relation to the nutrient requirements. The sporophylls of U. pinnatifida formed zoosporangia when they had N and P contents greater than 1.4 kgN/m3 and 0.74 kgP/m3. This indicates that these values are the critical nutrient levels for zoospore formation in U. pinnatifida. In the sporophytes of A. crassifolia, many sporophylls with zoosporangia showed nutrient contents higher than 6.25 kgN/m3 and 1.70 kgP/m3. These results suggest that the U. pinnatifida can form zoospores at lower levels of N and P contents than A. crassifolia. Both species often formed zoosporangial sori on the blades in the late period of each reproductive season. The fertile parts of the blade showed N and P contents higher than the critical levels. This phenomenon indicates that the blades have the capability to form zoosporangial sori if there is a sufficient accumulation of nutrients for zoospore formation. The zoospore formation on the blade seems to be accomplished by an overflow of excess nutrients from sporophylls into the blade, or by accumulating sufficient nutrients to form sori even if the sporophylls are not formed.
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Regulation of Sorus Formation by Auxin in Laminariales Sporophyte
Journal of Applied Phycology, 2006Co-Authors: Tomoki Kai, Hajime Yasui, Kazumi Nimura, Hiroyuki MizutaAbstract:Young sporophytes of Laminaria japonica Areshoug were cultured in six indole-acetic acid (IAA) concentrations (0, 10−8, 10−7, 10−6, 10−5, 10−4 M) to examine the effect of auxin on growth. The effects of auxin on sorus formation were also examined by using discs taken from the adult sporophyte. The auxin contents and IAA oxidase activities in the thallus and sorus parts of the sporophyte were determined with the blade and sporophyll of other Laminariales plants, Undaria pinnatifida (Harvey) Suringar and Alaria crassifolia Kjellman. The young sporophytes of L. japonica showed highest elongation rate in 10−5 M IAA. In contrast, the sorus formation on the discs cultured in 10−5 M IAA was markedly delayed in comparison with other concentrations, indicating that sorus formation was suppressed by IAA. Free and conjugated auxin contents were lower in the reproductive parts than in the vegetative parts. In three Laminariales sporophytes, IAA oxidase activity was about 3–9 times higher in the reproductive parts than in the vegetative parts. Taken together these results suggest that the growth and reproduction of Laminariales sporophytes are regulated by internal auxin levels. Elucidating the regulation mechanism is likely to provide information that is important for the management of plant production and the assessment of the physiological status of plants in the field.
Hajime Yasui - One of the best experts on this subject based on the ideXlab platform.
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Nutrient requirement for zoospore formation in two Alariaceous plants Undaria pinnatifida (Harvey) Suringar and Alaria crassifolia Kjellman (Phaeophyceae: Laminariales)
Fisheries Science, 2006Co-Authors: Takeshi Kumura, Hajime Yasui, Hiroyuki MizutaAbstract:Sporophyll formation in two Alariaceous plants, Undaria pinnatifida and Alaria crassifolia, was studied in relation to the nutrient requirements. The sporophylls of U. pinnatifida formed zoosporangia when they had N and P contents greater than 1.4 kgN/m3 and 0.74 kgP/m3. This indicates that these values are the critical nutrient levels for zoospore formation in U. pinnatifida. In the sporophytes of A. crassifolia, many sporophylls with zoosporangia showed nutrient contents higher than 6.25 kgN/m3 and 1.70 kgP/m3. These results suggest that the U. pinnatifida can form zoospores at lower levels of N and P contents than A. crassifolia. Both species often formed zoosporangial sori on the blades in the late period of each reproductive season. The fertile parts of the blade showed N and P contents higher than the critical levels. This phenomenon indicates that the blades have the capability to form zoosporangial sori if there is a sufficient accumulation of nutrients for zoospore formation. The zoospore formation on the blade seems to be accomplished by an overflow of excess nutrients from sporophylls into the blade, or by accumulating sufficient nutrients to form sori even if the sporophylls are not formed.
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Regulation of Sorus Formation by Auxin in Laminariales Sporophyte
Journal of Applied Phycology, 2006Co-Authors: Tomoki Kai, Hajime Yasui, Kazumi Nimura, Hiroyuki MizutaAbstract:Young sporophytes of Laminaria japonica Areshoug were cultured in six indole-acetic acid (IAA) concentrations (0, 10−8, 10−7, 10−6, 10−5, 10−4 M) to examine the effect of auxin on growth. The effects of auxin on sorus formation were also examined by using discs taken from the adult sporophyte. The auxin contents and IAA oxidase activities in the thallus and sorus parts of the sporophyte were determined with the blade and sporophyll of other Laminariales plants, Undaria pinnatifida (Harvey) Suringar and Alaria crassifolia Kjellman. The young sporophytes of L. japonica showed highest elongation rate in 10−5 M IAA. In contrast, the sorus formation on the discs cultured in 10−5 M IAA was markedly delayed in comparison with other concentrations, indicating that sorus formation was suppressed by IAA. Free and conjugated auxin contents were lower in the reproductive parts than in the vegetative parts. In three Laminariales sporophytes, IAA oxidase activity was about 3–9 times higher in the reproductive parts than in the vegetative parts. Taken together these results suggest that the growth and reproduction of Laminariales sporophytes are regulated by internal auxin levels. Elucidating the regulation mechanism is likely to provide information that is important for the management of plant production and the assessment of the physiological status of plants in the field.
