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Yufeng Yang - One of the best experts on this subject based on the ideXlab platform.
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potential bioremediation effects of seaweed Gracilaria lemaneiformis on heavy metals in coastal sediment from a typical mariculture zone
Chemosphere, 2020Co-Authors: Hongtian Luo, Qing Wang, Zhiwei Liu, Shuangyao Wang, Aimin Long, Yufeng YangAbstract:Seaweeds are good bio-monitors of heavy metals pollution in coastal seawater. In the present study, the potential bioremediation effects of cultivated Gracilaria lemaneiformis on heavy metals in Nan'ao coastal sediment from a typical mariculture zone, South China were evaluated. Sediment samples were collected from five different zones (Gracilaria cultivation zone, G; Fish culture zone, F; Shellfish culture zone, S; Transition zone, T; Control zone, C) from December 2014 to July 2015. The concentrations of Cd, Pb, Cu, and Zn in the sediments were significantly different among the various types of mariculture areas. The concentrations varied widely: Cd (0.04-1.02) μg g-1; Cu (1.19-37.70) μg g-1; Pb (8.45-74.45) μg g-1; Zn (36.80-201.24) μg g-1. The lowest heavy metal concentrations in the sediment were occurred at Gracilaria cultivation zone, while higher concentrations occurred at control zones and fish culture zones. The pollution load index, principal components and cluster analysis showed that heavy metal concentrations were the highest at fish culture zone, while the concentrations were the lowest at Gracilaria cultivation zone, and Gracilaria cultivation affects the heavy metals in the sediments. Gracilaria had strong adsorption capacities for heavy metals from seawater, showing the highest heavy metal Bioconcentration Factors in May (higher seaweed biomass period). Consequently, the results suggested that Gracilaria cultivation influences the heavy metal concentrations in sediments from the typical coastal mariculture zone. Gracilaria cultivation has the potential to bioremediate heavy metals in the coastal sediments. Therefore, Gracilaria cultivation can add environmental advantages and ecological values to coastal mariculture zones.
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cultivation of seaweed Gracilaria in chinese coastal waters and its contribution to environmental improvements
Algal Research-Biomass Biofuels and Bioproducts, 2015Co-Authors: Yufeng Yang, Wei Zhou Chen, Qing Wang, Zhaoyang Chai, Shijun JiangAbstract:Abstract Over the past decade, the large-scale cultivation of seaweed Gracilaria has expanded rapidly in the Chinese coastal waters. The production of Gracilaria increased from 50,536 tons (t, dry weight) in 2003 to 114,722 t in 2010. The production of the seaweed ranks third only to kelps Saccharina (formerly referred to as Laminaria ) and Undaria in China. Nan'ao located in Shantou City, Guangdong Province has been successfully developed as one of the major cultivation bases of Gracilaria lemaneiformis at an industrial scale in South China since 2000, and the farmed area increased by 11,538-fold from 0.13 ha in 2000 to 1500 ha in 2011. From lab-scale study to field industrial practice, it has been documented that Gracilaria cultivation is beneficial in environmental improvements such as mitigating eutrophication, controlling harmful algal blooms, maintaining healthy mariculture systems, and sequestrating CO 2 . Gracilaria may significantly remediate contaminants in mariculture ecosystems and improve the water environment, and its cultivation provides a new approach to coastal environmental improvement in China and the world.
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growth of Gracilaria lemaneiformis under different cultivation conditions and its effects on nutrient removal in chinese coastal waters
Aquaculture, 2006Co-Authors: Yufeng Yang, Xiugeng Fei, Jinming Song, Guangce Wang, Ik Kyo ChungAbstract:Gracilaria lemaneiformis (Bory) Daws has been extensively cultivated as a source of commercial agar and the ecomaterials in Shenao Bay, Guangdong Province, Jiaozhou Bay, Shandong Province and other waters in China. This paper examines the in situ suspended farming of G. lemaneiformis using raft cultivation under different conditions and its effects on nutrient removal in the laboratory. The results showed that cultivated Gracilaria grew well in both Shenao Bay and Jiaozhou Bay. The biomass of Gracilaria increased from 50 to 775 g m(-1) (fresh weight) during 28 days, with special growth rate (SPG) 13.9% d(-1) under horizontal cultivation in Jiaozhou Bay. Light, temperature, nutrient supply, as well as cultivation treatments such as initial density, and depth of suspension seaweed were important to the growth of Gracilaria. The highest biomass production was observed in the horizontal culture condition (0.0 m) and 0.5-1.5 m deep layer in Jiaozhou Bay. However, the highest growth rate in Shenao Bay appeared under the lowest initial stocking density treatment. In the laboratory, the aquarium experiments (fish and seaweed culture systems) demonstrated that Gracilaria was able to remove inorganic nutrients effectively. The concentration of NH4+-N decreased by 85.53% and 69.45%, and the concentration of PO4-P decreased 65.97% and 26.74% in aquaria with Gracilaria after 23 days and 40 days, respectively. The results indicate that Gracilaria has the potential to remove excess nutrient from coastal areas, and the large-scale cultivation of G. lemaneiformis could be effective to control eutrophication in Chinese coastal waters. (c) 2005 Elsevier B.V. All rights reserved.
Michael Friedlander - One of the best experts on this subject based on the ideXlab platform.
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Gracilaria and its epiphytes: 4. The response of two Gracilaria species to Ulva lactuca in a bacteria-limited environment
Journal of Applied Phycology, 2001Co-Authors: Michael Friedlander, Florian Weinberger, Yoel Kashman, Clinton J. DawesAbstract:The responses of Gracilaria lemaneiformis, an easily epiphytized host,and the relatively resistant G. cornea mutant, to the green alga Ulva lactuca were studied using biculture experiments with and withoutantibiotics. Both Gracilaria species grown with and without U.lactuca showed different levels of growth rate, release of hydrogenperoxide and of halogenated hydrocarbons. These quantitative differencesled to a successful response against Ulva lactuca in the case of G.cornea mutant and to a failure in response in the case of G.lemaneiformis. The response of each Gracilaria species to U.lactuca was qualitatively similar to its response to bacteria. This suggeststhe involvement of oligosaccharide elicitors produced in the presence ofepiphytes and bacteria. A clear Gracilaria inhibition was demonstratedwith extracts of the culture medium. It appears that hydrogen peroxide,halogenated hydrocarbons and oligosaccharides may be components of theinhibitory activity of the extracts. The responses of Gracilaria speciesto the presence of U. lactuca suggest the characterization of adefence response.
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Fish as potential biocontrollers of Gracilaria (Rhodophyta) culture
Aquaculture, 1996Co-Authors: Michael Friedlander, Nora Weintraub, Arik Freedman, Joni Sheer, Zvi Snovsky, James Shapiro, George Wm. KissilAbstract:Abstract Food preferences were studied in 11 fish species in order to find out their potential as epiphyte and copepod controllers in Gracilaria cultures. The fish were exposed to mixtures of Gracilaria and Ulva with other epiphytes included, in the presence of copepods, and the intestinal content of the fish was determined. Aphanius dispar and Tilapia zillii (acclimated to seawater) emerged as potentially useful epiphyte controllers, and Aphanius dispar and Diplodus annularis were potential copepod controllers in Gracilaria cultures.
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Cultivation of Gracilaria in outdoor tanks and ponds
Journal of Applied Phycology, 1995Co-Authors: Michael Friedlander, Israel LevyAbstract:This review deals with the major problems of unattached Gracilaria intensive cultivation in outdoor tanks and ponds. These problems are presented through the main variables affecting the Gracilaria annual yield and the updated solutions evolved. The physical variables include tank and pond structure, seawater characteristics such as velocity, agitation practice, exchange rate, and salinity, light characteristics such as quantity and quality, and temperature modelling. The chemical variables include nutrient composition and regime of application, and inorganic carbon supply with the pH changes involved. The biological variables include seaweed density, epiphyte competition, grazer damage, bacterial disintegration, integrated mariculture and strain selection. The experience gained in the Israeli research on Gracilaria cultivation is discussed in view of other Gracilaria and seaweed intensive cultivation research.
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Seasonal growth activity of local and foreign gracilarioid strains in Israel
Journal of Applied Phycology, 1994Co-Authors: Israel Levy, Michael FriedlanderAbstract:Six gracilarioid strains originating from different climatical environments were cultured in two cultivation systems: a short-term indoor one with a cross gradiant table, and a long-term outdoor one. Seasonal growth performances of the different strains were determined. The growth results in the two culture systems showed similar trends. The tropical species. Gracilaria cornea and G. cornea mutant, showed highest growth rates during summer and no growth at all during winter. The temperate species, Gracilaria verrucosa and Gracilariopsis lemaneiformis , showed best growth performances during winter with small fluctuations between seasons. The subtropical species Gracilaria conferta (local) showed seasonal growth fluctuations all over the year. The foreign species definitely did not acclimate under local conditions, but successfully preserved their original response to temperature. Regression equations confirmed that temperature was the dominant environmental variable in most of the gracilarioid strains. The growth rate results obtained showed encouraging prospects for high algal productivity as compared to other cultivation systems. Seasonal cultivation strategy of Gracilaria spp. in Israel is discussed.
Qing Wang - One of the best experts on this subject based on the ideXlab platform.
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potential bioremediation effects of seaweed Gracilaria lemaneiformis on heavy metals in coastal sediment from a typical mariculture zone
Chemosphere, 2020Co-Authors: Hongtian Luo, Qing Wang, Zhiwei Liu, Shuangyao Wang, Aimin Long, Yufeng YangAbstract:Seaweeds are good bio-monitors of heavy metals pollution in coastal seawater. In the present study, the potential bioremediation effects of cultivated Gracilaria lemaneiformis on heavy metals in Nan'ao coastal sediment from a typical mariculture zone, South China were evaluated. Sediment samples were collected from five different zones (Gracilaria cultivation zone, G; Fish culture zone, F; Shellfish culture zone, S; Transition zone, T; Control zone, C) from December 2014 to July 2015. The concentrations of Cd, Pb, Cu, and Zn in the sediments were significantly different among the various types of mariculture areas. The concentrations varied widely: Cd (0.04-1.02) μg g-1; Cu (1.19-37.70) μg g-1; Pb (8.45-74.45) μg g-1; Zn (36.80-201.24) μg g-1. The lowest heavy metal concentrations in the sediment were occurred at Gracilaria cultivation zone, while higher concentrations occurred at control zones and fish culture zones. The pollution load index, principal components and cluster analysis showed that heavy metal concentrations were the highest at fish culture zone, while the concentrations were the lowest at Gracilaria cultivation zone, and Gracilaria cultivation affects the heavy metals in the sediments. Gracilaria had strong adsorption capacities for heavy metals from seawater, showing the highest heavy metal Bioconcentration Factors in May (higher seaweed biomass period). Consequently, the results suggested that Gracilaria cultivation influences the heavy metal concentrations in sediments from the typical coastal mariculture zone. Gracilaria cultivation has the potential to bioremediate heavy metals in the coastal sediments. Therefore, Gracilaria cultivation can add environmental advantages and ecological values to coastal mariculture zones.
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cultivation of seaweed Gracilaria in chinese coastal waters and its contribution to environmental improvements
Algal Research-Biomass Biofuels and Bioproducts, 2015Co-Authors: Yufeng Yang, Wei Zhou Chen, Qing Wang, Zhaoyang Chai, Shijun JiangAbstract:Abstract Over the past decade, the large-scale cultivation of seaweed Gracilaria has expanded rapidly in the Chinese coastal waters. The production of Gracilaria increased from 50,536 tons (t, dry weight) in 2003 to 114,722 t in 2010. The production of the seaweed ranks third only to kelps Saccharina (formerly referred to as Laminaria ) and Undaria in China. Nan'ao located in Shantou City, Guangdong Province has been successfully developed as one of the major cultivation bases of Gracilaria lemaneiformis at an industrial scale in South China since 2000, and the farmed area increased by 11,538-fold from 0.13 ha in 2000 to 1500 ha in 2011. From lab-scale study to field industrial practice, it has been documented that Gracilaria cultivation is beneficial in environmental improvements such as mitigating eutrophication, controlling harmful algal blooms, maintaining healthy mariculture systems, and sequestrating CO 2 . Gracilaria may significantly remediate contaminants in mariculture ecosystems and improve the water environment, and its cultivation provides a new approach to coastal environmental improvement in China and the world.
Hongtian Luo - One of the best experts on this subject based on the ideXlab platform.
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potential bioremediation effects of seaweed Gracilaria lemaneiformis on heavy metals in coastal sediment from a typical mariculture zone
Chemosphere, 2020Co-Authors: Hongtian Luo, Qing Wang, Zhiwei Liu, Shuangyao Wang, Aimin Long, Yufeng YangAbstract:Seaweeds are good bio-monitors of heavy metals pollution in coastal seawater. In the present study, the potential bioremediation effects of cultivated Gracilaria lemaneiformis on heavy metals in Nan'ao coastal sediment from a typical mariculture zone, South China were evaluated. Sediment samples were collected from five different zones (Gracilaria cultivation zone, G; Fish culture zone, F; Shellfish culture zone, S; Transition zone, T; Control zone, C) from December 2014 to July 2015. The concentrations of Cd, Pb, Cu, and Zn in the sediments were significantly different among the various types of mariculture areas. The concentrations varied widely: Cd (0.04-1.02) μg g-1; Cu (1.19-37.70) μg g-1; Pb (8.45-74.45) μg g-1; Zn (36.80-201.24) μg g-1. The lowest heavy metal concentrations in the sediment were occurred at Gracilaria cultivation zone, while higher concentrations occurred at control zones and fish culture zones. The pollution load index, principal components and cluster analysis showed that heavy metal concentrations were the highest at fish culture zone, while the concentrations were the lowest at Gracilaria cultivation zone, and Gracilaria cultivation affects the heavy metals in the sediments. Gracilaria had strong adsorption capacities for heavy metals from seawater, showing the highest heavy metal Bioconcentration Factors in May (higher seaweed biomass period). Consequently, the results suggested that Gracilaria cultivation influences the heavy metal concentrations in sediments from the typical coastal mariculture zone. Gracilaria cultivation has the potential to bioremediate heavy metals in the coastal sediments. Therefore, Gracilaria cultivation can add environmental advantages and ecological values to coastal mariculture zones.
Giuseppe C. Zuccarello - One of the best experts on this subject based on the ideXlab platform.
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Gracilaria phuquocensis sp. nov., a new flattened Gracilaria species (Gracilariales, Rhodophyta), previously recognized as G. mammillaris, from the southern coast of Vietnam
2020Co-Authors: Narongrit Muangmai, Sunisa Kheauthong, Zhongmin Sun, Giuseppe C. ZuccarelloAbstract:© 2019 Japanese Society of Phycology Flattened Gracilaria species are widely distributed along the coasts of the South China Sea with more than 20 species recorded. Within the South China Sea, Gracilaria mammillaris has only been reported from Vietnam, but this species is likely restricted to the western Atlantic. This study aimed to reevaluate the taxonomic status of Vietnamese specimens of ‘G. mammillaris’ using combined morphological and molecular data. Our data clearly indicated that Vietnamese specimens were morphologically and genetically distinct from authentic G. mammillaris from the western Atlantic, and also other described flat Gracilaria species. We, therefore, propose that specimens from Vietnam originally identified as G. mammillaris be designated as a new species, Gracilaria phuquocensis sp. nov. Morphologically, G. phuquocensis can be distinguished from other flat Gracilaria species by its small thallus size, narrower blades, many medullary layers, abundant basal nutritive filaments within mature cystocarps, and tetrasporangial nemathecium. Our rbcL sequence analyses showed that the new species was sister to Gracilaria rhodymenioides from Thailand, and these two species formed a clade with cylindrical Gracilaria species. Our study contributes to clarification of the taxonomic status of misidentified specimens attributed to the flattened Gracilaria species in the South China Sea.
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Gracilaria phuquocensis sp. nov., a new flattened Gracilaria species (Gracilariales, Rhodophyta), previously recognized as G. mammillaris, from the southern coast of Vietnam
Phycological Research, 2019Co-Authors: Narongrit Muangmai, Sunisa Kheauthong, Zhongmin Sun, Giuseppe C. ZuccarelloAbstract:Flattened Gracilaria species are widely distributed along the coasts of the South China Sea with more than 20 species recorded. Within the South China Sea, Gracilaria mammillaris has only been reported from Vietnam, but this species is likely restricted to the western Atlantic. This study aimed to reevaluate the taxonomic status of Vietnamese specimens of ‘G. mammillaris’ using combined morphological and molecular data. Our data clearly indicated that Vietnamese specimens were morphologically and genetically distinct from authentic G. mammillaris from the western Atlantic, and also other described flat Gracilaria species. We, therefore, propose that specimens from Vietnam originally identified as G. mammillaris be designated as a new species, Gracilaria phuquocensis sp. nov. Morphologically, G. phuquocensis can be distinguished from other flat Gracilaria species by its small thallus size, narrower blades, many medullary layers, abundant basal nutritive filaments within mature cystocarps, and tetrasporangial nemathecium. Our rbcL sequence analyses showed that the new species was sister to Gracilaria rhodymenioides from Thailand, and these two species formed a clade with cylindrical Gracilaria species. Our study contributes to clarification of the taxonomic status of misidentified specimens attributed to the flattened Gracilaria species in the South China Sea.
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A new flat Gracilaria: Gracilaria lantaensis sp. nov. (Gracilariales, Rhodophyta) from the Andaman coast of Thailand
Phycologia, 2014Co-Authors: Narongrit Muangmai, Giuseppe C. Zuccarello, Thidarat Noiraksa, Khanjanapaj LewmanomontAbstract:Collection of a flat red alga of the genus Gracilaria from the Andaman coast of Thailand was described as a new species, G. lantaensis sp. nov. based on detailed morphological characteristics and rbcL sequence analysis. This species typically grew intertidally on exposed mud-sand shores. It was characterized by its slender thalli with narrow-bladed branches, its smooth margin with a few brachlets and its reddish-pink color. Spermatangial conceptacles were of the textorii-type. Cystocarps were spherical and possessed numerous nutritive filaments at lateral and basal positions in the cystocarp cavity. Gracilaria lantaensis was morphologically similar to G. yamamotoi but differed in branching pattern and cystocarp structure. RbcL sequence data also indicated the genetic distinction between G. lantaensis and other species of Gracilaria. Gracilaria lantaensis was grouped with a major assemblage of Gracilaria species, and sister to some Indian Ocean species with denticulate margins, e.g. G. beckeri, G. capensis...
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Gracilaria species (Gracilariaceae, Rhodophyta) from southeastern Australia, including a new species, Gracilaria perplexa sp. nov.: Morphology, molecular relationships and agar content
Phycological Research, 2002Co-Authors: Kellie Byrne, Giuseppe C. Zuccarello, John A. West, Ming-long Liao, Gerald T. KraftAbstract:SUMMARY Select species of the agarophyte Gracilaria were studied from southeastern Australia. The morphology and anatomy of species is described and molecular relations are inferred based on plastid and mitochon-drial DNA sequence data. Agar yields and qualities are determined for each species. Gracilaria chilensis, found in Tasmania and Victoria, is morphologically and molecularly similar to G. chilensis from New Zealand and Chile and has low agar yields of 11–16%. Gracilaria cliftonii from Victoria, has high crude agar yield (52%) and is molecularly uniform. Gracilaria perplexa sp. nov., known only from Botany Bay, New South Wales, has an agar yield of 39%. The agar of G. perplexa is unusual in requiring the addition of 0.1 mol L−1 NaCl for alcohol precipitation and is cold-water (25°C) soluble because of the very high sulfate ester content. Molecular phylogeny shows that G. perplexa is closely related to Gracilaria preissiana from western Australia, but differs from the latter in its reduced branching and narrower more terete axes.
