Nutrient Bioextraction Research Articles

Recovery of eutrophized marine ecosystems using the European flat oyster, Ostrea edulis

Abstract The development of tourism and intensification of agriculture has released large amounts of nitrogen and phosphorus into the Mar Menor coastal lagoon in South‐east Spain, resulting in a phytoplankton bloom in 2016. This bloom turned the clear and transparent waters turbid and greenish, and killed approximately 85% of benthic macrophytes. Nutrient bioextraction by flat oysters, Ostrea edulis, has been proposed for remediation of these eutrophication events and water quality recovery. This research aims to quantify the clearance rate and investigate the genetic origin of Mar Menor oysters under eutrophized conditions for potential applications to bioremediation projects. Oligotrophic and eutrophic conditions were replicated in the laboratory, and oyster feeding behaviour (i.e. clearance rates, ingestion rates, absorption efficiency and absorption rates) were studied using a flow‐through system. The genetic characterization of oysters showed no significant difference between individuals from the Mar Menor and individuals collected from a nearby Mediterranean bed (Tabarca Island). Based on the physiological results observed, oysters were grouped into high‐feeder (HF) and low‐feeder (LF) categories according to their clearance rate, that was 3‐fold higher in the HF group. Different responses in feeding behaviour were observed under eutrophic conditions in both oyster groups. Constraints in the absorption capacity of LF oysters seemed to be related to their reduced filtering activity. Lower body condition of LF oysters was evidenced by their negative scope for growth value. From this work, several conclusions can be drawn for future restoration/bioextraction actions: (i) the recovery of half of the oyster population that existed in the past would act as an effective top‐down control on the phytoplankton community; (ii) using clearance rate measurements is recommended to select oysters as broodstock; and (iii) Mediterranean oysters could be used as broodstock in the event that Mar Menor oysters fail to reproduce.

Bioextractive aquaculture as an alternative nutrient management strategy for water resource recovery facilities

Advanced nutrient removal in water resource recovery facilities (WRRFs) can reduce coastal eutrophication, but can increase economic costs and indirect environmental impacts associated with energy and materials usage for WRRF construction and operation. A strategy of interest to reduce coastal eutrophication is the cultivation of seaweeds in proximity to WRRF discharge plumes to bioextract nutrients from coastal waters. We report economic and environmental trade-offs of this proposed strategy for a 1,170 m3·d−1 (0.31 mgd) WRRF in Boothbay Harbor, Maine, targeting a Water Environment Research Federation (WERF) level 2 effluent nitrogen goal of 3 mg-N·L−1. The scenarios investigated include WRRF upgrade and year-round nutrient bioextractive aquaculture (Saccharina latissima and Gracilaria tikvahiae cultivation) with end uses of bioenergy feedstock, fertilizer, or food. Based on biomass production characteristics and tissue nitrogen contents in Boothbay Harbor, an aquaculture site of 5.4 hectares would bioextract equivalent nitrogen mass as WRRF upgrade to meet level 2 nitrogen effluent goals. Using a techno-economic analysis, the cost of a WRRF upgrade was estimated to be $0.31 m−3 wastewater treated. The cost of bioextractive seaweed aquaculture depended on beneficial use of seaweed. If dried and sold as sea vegetables (for human consumption), a net revenue of $0.72 m−3 wastewater treated could be generated. If dried and sold as commercial fertilizer, the net cost of nutrient removal would be $0.26 m−3 wastewater treated, less than the WRRF upgrade. However, if anaerobically digested to produce biogas, the net cost of treatment was estimated to be $0.499 m−3 wastewater treated. WRRF upgrade and bioextractive aquaculture significantly reduced marine eutrophication. Bioextractive aquaculture with use as biofuel feedstock had the best performance on human carcinogenic toxicity, global warming, and fossil resource scarcity, marine ecotoxicity, and freshwater ecotoxicity. Use of seaweed product as sea vegetables was favorable considering human non-carcinogenic toxicity, marine eutrophication, freshwater eutrophication, and terrestrial ecotoxicity. The study results imply that nutrient bioextraction by seaweed aquaculture may be attractive as an alternative to advanced nutrient removal technologies in small coastal WRRFs, providing potential economic and environmental benefits for nutrient management.

Evaluation of nutrient bioextraction by seaweed and shellfish aquaculture in Korea

AbstractAlthough Korea is third in seaweed production and second in shellfish production globally, this is the first study evaluating ecosystem services of seaweed and shellfish aquaculture in Korea. The objective of this study is to evaluate nutrient bioextraction capacities of major seaweed and shellfish species aquacultured in Korea. C (C) removal of three major aquacultured seaweed species, Neopyropia yezoensis, Saccharina japonica, and Undaria pinnatifida were 24,247, 8,423, and 12,758 tons, respectively, in 2016. N (N) removal of these species was 4,088, 732, and 1,244 tons, respectively. The C and N removal of the Pacific oysters (Crassostrea gigas) were 14,693 and 1,050 tons, respectively. Manila clams (Venerupis philippinarum) removed 2,120 tons of C and 136.5 tons of N. Together, 161,846 tons of CO2 and 7,251 tons of N were removed by three major seaweed species and two shellfish species. These values are significant amounts, equivalent to 5.7% of CO2 and 8.6% of N discharged from all wastewater treatment plants in Korea. These results suggest that nutrient bioextraction by aquacultured seaweed and shellfish can be a cost efficient, affordable, and equitable solution for coastal nutrient management programs in Korea and elsewhere.

Increased light availability modulates carbon and nitrogen accumulation in the macroalga Gracilariopsis lemaneiformis (Rhodophyta) in response to ocean acidification

The economically important red macroalga Gracilariopsis lemaneiformis has demonstrated positive ecological functions in nutrient bioextraction efficiency and high harvestable biomass, as well as being a food and agar source owing to its richness in proteins and polysaccharides. Carbon dioxide (CO2)-induced ocean acidification has resulted in mixed nutrient compound accumulations in this marine autotroph. G. lemaneiformis also experiences light variations resulting from self-shading and varied cultivation depths. Therefore, a factorial coupling experiment was conducted to examine how growth, photosynthesis performance, soluble cell components and metabolic enzyme-driven activities respond to light availability changes and CO2 enrichment. The ocean acidification enhanced the growth characteristics, total carbon/nitrogen ratios and metabolic nutrient accumulation processes in G. lemaneiformis regardless of the light level. Photosynthetic performances, including relative electron transport rate and maximum photochemical quantum yield, were increased by high pCO2 concentrations, resulting in soluble carbohydrate accumulation. The carbon and nitrogen accumulations might result from variations in carbonic anhydrase and nitrate reductase activities under high pCO2 conditions. The soluble protein and free amino acids contents declined in response to CO2 elevation, and this effect was more pronounced as the light intensity increased. Thus, future climate changes may cause greater algal biomass accumulations, but they may negatively affect the cell composition and nutritional quality of G. lemaneiformis.

Seaweed resources of Korea

Abstract Korea has a long history of utilizing seaweeds, as the country has a high biodiversity of seaweeds. The abundance and composition of seaweed species have changed over the past decades due to climate change and anthropogenic influences. Some species showed a significant extension of their distribution range to the north while some species declined. Some areas have even become barren ground. Korea has put extensive effort into restoring the seaweed resources in these deforested areas. Korea is one of the most advanced countries in the World in terms of seaweed aquaculture. However, the aquacultured species are mostly limited to three genera, Saccharina, Undaria and Pyropia/Porphyra, which represent 96% of the entire seaweed production in the country. Korea has developed highly advanced cultivation technologies as well as various cultivars using breeding and hybridization technologies for these species. There has also been considerable effort in developing environmentally sustainable aquaculture systems using seaweed cultivation (e. g. integrated multi-trophic aquaculture, nutrient bioextraction and biofloc). This study discusses the current status and challenges of the above mentioned topics in detail. In addition, the present study encourages South and North Korean scientists to collaborate in the study of seaweed resources at the border of these two countries.

A field scale evaluation of Gracilaria lemaneiformis co-cultured with Crassostrea gigas as a nutrient bioextraction strategy in Yantian Bay, China

Nutrient bioextraction using Gracilaria lemaneiformis co-cultured with Crassostrea gigas in a eutrophic, intensive mariculture area was evaluated over 49 days in Yantian Bay, which is an enclosed bay within Sansha Bay, China. The amount of nitrogen removed by G. lemaneiformis was 4.07 ± 0.25 kg and 4.49 ± 0.57 kg per ton (FW) at depths of 0.4–0.8 m and 1.0–1.2 m, respectively. The ranges of ammonium-nitrogen (NH4-N), nitrite-nitrogen (NO2-N), nitrate-nitrogen (NO3-N), and inorganic phosphate (PO4-P) reduction efficiencies in the co-cultured area were 39.22–80.34%, 4.70–26.14%, 13.42–48.84%, and 25.33–41.36%, respectively. The total wet weight of harvested G. lemaneiformis was 5.44 and 3.92 times greater than the initial mass (500 g FW/m), with highest specific growth rates (SGR) of 4.67 ± 0.21%/d and 3.44 ± 0.18%/d at 0.4–0.8 m and 1.0–1.2 m, respectively. A total of 3.11 kg of nitrogen could be removed from the co-cultured area per ton of C. gigas harvested with a total length (TL) of 80 ± 12 mm. Based on the nitrogen balance in this co-cultured system, the largest proportion of nitrogen removal from the co-cultured system was the harvest production of G. lemaneiformis (25.44%), followed by C. gigas (8.27%). The quantity of nitrogen excreted and metabolized by C. gigas was 33.40 kg, which could be entirely assimilated by the G. lemaneiformis during the experimental period. Based on these results, at least 6.76 tons of G. lemaneiformis should be co-cultured per ton of C. gigas (77–80 mm TL) to remove the nitrogen produced by C. gigas in this mariculture area. The results of this study indicate that the co-culture G. lemaneiformis with C. gigas is an environmentally-friendly mariculture method which could effectively remove surplus nutrients and reduce the environmental impact of mariculture areas.

Growth and nutrient uptake of Gracilaria lemaneiformis under different nutrient conditions with implications for ecosystem services: A case study in the laboratory and in an enclosed mariculture area in the East China Sea

The growth and nutrient uptake of Gracilaria lemaneiformis under different nutrient conditions, with implications for ecosystem services, were evaluated in the laboratory and in an enclosed mariculture sea area in Yantian Bay at the coast of East China Sea. In laboratory experiments, the specific growth rate (SGR) ranged 1.29%/d–7.99%/d, and nitrogen (N), phosphorus (P), and dissolved inorganic carbon (C) uptake rate was 0.067–1.603 μmol/(g∙h), 0.002–0.069 μmol/(g∙h), and 4.01–31.25 μmol/(g∙h), respectively, under different nutrient conditions. In field experiments, the SGR ranged from 6.30%/d to 13.00%/d, and the average C sequestration rate was 9.25 mg/(g DW·h) and 6.68 mg/(g DW·h) in the G. lemaneiformis cultivation area (region 1) and fish cage area (region 4), respectively. The NH4+-N uptake rate of G. lemaneiformis was the highest in region 1 and region 4 with 56.98 ± 4.81 μg/(g DW·h) and 38.68 ± 7.12 μg/(g DW·h), respectively. The maximum removal efficiency of NH4+-N, NO3−-N, NO2--N, and PO43--P were 45.99–59.79%, 13.10–30.21%, 12.88–14.11%, and 27.07–31.49% in G. lemaneiformis cultivated areas compared with those in fish cage area. The extrapolated results showed that 1192.03 tonnes of C, 128.10 tonnes of N and 15.89 tonnes of P would be simultaneously sequestered from the seawater through G. lemaneiformis cultivation in Yantian Bay. Results indicated that G. lemaneiformis had high growth rates and nutrient removal efficiencies under different nutrient conditions, which made it a good candidate for seaweed/animals integrated multi-trophic aquaculture in nutrient bioextraction and economic diversification.

Characterization of agar from Gracilaria tikvahiae cultivated for nutrient bioextraction in open water farms

Gracilaria tikvahiae, an endemic western North Atlantic red alga, was cultivated for nutrient bioextraction in urbanized estuarine waters in Long Island Sound and the Bronx River Estuary, USA. This study assesses the feasibility of an integrated approach of using G. tikvahiae produced in this bioextraction system as sustainable biomass source for agar production. Agars were extracted after alkaline pre-treatment and characterized in terms of gelling strength, chemical composition, chemical structure and gel structure. Results indicated that this seaweed performed similar to other cultivated Gracilaria in terms of extraction yield and gelling strength of the agar. Differences between sites were not significant in terms of agar gel strength, though yield was higher at Long Island Sound. The extracted agars were sulfated, methylated and with no detectable pyruvate substituents. It is possible to use an integrated strategy of nutrient bioextraction in urbanized estuarine waters and agar exploitation with G. tikvahiae.

Nutrient bioextraction and microalgae growth inhibition using submerged macrophyte Myriophyllum spicatum in a low salinity area of East China Sea

Myriophyllum spicatum was cultivated in a low salinity area of Hangzhou Bay (salinity 5.8–6.5), from August to October in 2016, to evaluate the abilities of its nutrient bioextraction and microalgae growth inhibition. During the 72-day cultivation period, M. spicatum had a specific growth rate (SGR) of 6.23%day−1 and increased 20-fold in biomass (wet weight). Tissue C, N and P assimilation quantities of M. spicatum were found to be 3279.39kg, 360.61kg and 26.97kg, respectively. The concentration of NH4-N, NO3-N, NO2-N and PO4-P after M. spicatum cultivation was decreased by 47.92%, 58.28%, 36.40% and 55.57%, respectively. The phytoplankton density was decreased from 1064.60×104cellsL−1 to 12.85×104cellsL−1. These results indicated that cultivation of M. spicatum can help in nutrient bioextraction and microalgae growth inhibition in low salinity marine water bodies.

Cultivation of the Ribbed Mussel (Geukensia demissa) for Nutrient Bioextraction in an Urban Estuary.

Shellfish aquaculture is gaining acceptance as a tool to reduce nutrient over enrichment in coastal and estuarine ecosystems through the feeding activity of the animals and assimilation of filtered particles in shellfish tissues. This ecosystem service, provided by the ribbed mussel (Geukensia demissa), was studied in animals suspended from a commercial mussel raft in the urban Bronx River Estuary, NY, in waters closed to shellfish harvest due to bacterial contamination. Naturally occurring populations of ribbed mussels were observed to be healthy and resilient in this highly urbanized environment. Furthermore, mussels grown suspended in the water column contained substantially lower concentrations of heavy metals and organic contaminants in their tissues than blue mussels (Mytilus edulis) collected at a nearby benthic site. Spat collection efforts from shore and within the water column were unsuccessful; this was identified as a key bottleneck to future large-scale implementation. Filtration experiments indicated that a fully stocked G. demissa raft would clear an average 1.2 × 107 L of Bronx River Estuary water daily, removing 160 kg of particulate matter from the water column, of which 12 kg would be absorbed into mussel digestive systems. At harvest, 62.6 kg of nitrogen would be sequestered in mussel tissue and shell. These values compare favorably to other resource management recovery methods targeting agricultural and stormwater nitrogen sources.

Cultivation of a morphologically distinct strain of the sugar kelp, Saccharina latissima forma angustissima, from coastal Maine, USA, with implications for ecosystem services

Consumer interest and demand for North Atlantic sourced sea vegetables drives opportunities for aquaculture development in the northeast USA. The unique morphology and desirable culinary traits of the wild narrow-bladed kelp, Saccharina latissima forma angustissima, were successfully translated into a cultivated crop on two geographically distinct open-water farms in Maine, USA. Environmental conditions, growth, and tissue analysis were quantified. Peak meristematic growth rates for blade length occurred from March through April at 2.85 (±0.34) cm day−1. The kelp was harvested from May through June with yields of up to 17 (±4.4) kg m−1 of line and plant density of 330 plants m−1 of line at the Bristol farm and yields of 13.3 (±6.2) kg wet weight m−1 line and a plant density of 400 plants m−1 of line at the Sorrento farm. Second season yields at Sorrento were on average 24.1 (±6.3) kg m−1 of line. Both farms grew significantly narrower blades of f. angustissima than of the sugar kelp, S. latissima. Common garden experiments with the two morphotypes identified trait stability for length and width, while blade ruffles and thickness varied with the environment. Calculations estimating the nutrient bioextraction capability of the cultivated f. angustissima kelp harvested in June reveal N removal of 88.7 kg ha−1 and C removal of 1666.7 kg ha−1 (combined farm site averages). Overall, this unique kelp form has the potential as a new aquaculture crop for the Gulf of Maine while providing several coastal ecosystem services.

Use of sugar kelp aquaculture in Long Island Sound and the Bronx River Estuary for nutrient extraction

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 531:155-166 (2015) - DOI: https://doi.org/10.3354/meps11331 Use of sugar kelp aquaculture in Long Island Sound and the Bronx River Estuary for nutrient extraction Jang K. Kim1,*, George P. Kraemer2, Charles Yarish3 1Department of Marine Sciences, University of Connecticut, 1 University Place, Stamford, CT 06901, USA 2Department of Environmental Studies, Purchase College, 735 Anderson Hill Road, Purchase, NY 10577, USA 3Department of Ecology and Evolutionary Biology, University of Connecticut, 1 University Place, Stamford, CT 06901, USA *Corresponding author: jang.kim@uconn.edu ABSTRACT: We previously demonstrated the suitability of seaweed aquaculture as a nutrient management tool, using the warm temperate rhodophyte Gracilaria tikvahiae McLachlan. The present follow-up study revealed an even higher nutrient bioextraction capacity in the cold-water species Saccharina latissima at 3 sites—the mouth of the Bronx River Estuary (Bronx, NY; BRE), western Long Island Sound (Fairfield, CT; WLIS) and central Long Island Sound (Branford, CT; CLIS), during winter and spring of the 2012-2013 growing season. These sites differ in temperature (BRE > CLIS > WIS), salinity (BRE < WLIS = CLIS) and nutrients (BRE >> WLIS = CLIS). We estimated that S. latissima could remove up to 180, 67 and 38 kg N ha-1 at BRE, WLIS and CLIS respectively, in a hypothetical kelp farm system with 1.5 m spacing between longlines. In the same hypothetical kelp farm system, the estimated carbon sequestration values are 1350 (BRE), 1800 (WLIS) and 1100 (CLIS) kg C ha-1. The potential monetary values of N sequestration by the sugar kelp are up to $1600 (BRE), $760 (WLIS) and $430 (CLIS) ha-1, if incorporated in the State of Connecticut Nitrogen Credit Trading Program and a carbon-pricing scheme. The potential economic values of C sequestration are $30-300 (BRE), $40-400 WLIS), and $24-240 (CLIS) ha-1. These results suggest that seaweed aquaculture is a useful technique for nutrient bioextraction in urbanized coastal waters, such as LIS and BRE. Alternation of the warm- and cold-water species would maximize nutrient bioextraction and augment other ecosystem services, producing economic benefits for the region while helping to manage non-source eutrophication. KEY WORDS: Nutrient bioextraction · Kelp aquaculture · Saccharina latissima · Estuary Full text in pdf format PreviousNextCite this article as: Kim JK, Kraemer GP, Yarish C (2015) Use of sugar kelp aquaculture in Long Island Sound and the Bronx River Estuary for nutrient extraction. Mar Ecol Prog Ser 531:155-166. https://doi.org/10.3354/meps11331 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 531. Online publication date: July 02, 2015 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2015 Inter-Research.

Transplant experiment to evaluate the feeding behaviour of the Atlantic ribbed mussel, Geukensia demissa, moved to a high inorganic seston area

In 2011–12, a field study demonstrated that ribbed mussels from two locations in the north-east Atlantic Coast of the USA used different feeding strategies to adapt to widely differing seston characteristics and achieve the same absorption efficiency. To investigate whether there was local, genetic adaptation of mussels in the two contrasting sites, we conducted a transplant experiment in 2012 in which mussels were moved from the high-plankton, low-inorganic waters of Milford Harbor, CT, to the high-inorganic, low-plankton waters of Hunts Point, Bronx, NY. Results showed that mussels from Milford adapted to the new, poorer-quality seston within 6 days of submersion in Hunts Point waters, which indicates that phenotypic plasticity in the species is sufficient to account for adaptability of the ribbed mussel to Hunts Point conditions. This adaptability makes the ribbed mussel a good candidate for environmental remediation technologies, such as nutrient bioextraction.

Field scale evaluation of seaweed aquaculture as a nutrient bioextraction strategy in Long Island Sound and the Bronx River Estuary

article i nfo Nutrient bioextraction using GracilariatikvahiaeMcLachlanwas tested attwosites: one off Fairfield,CT (LIS),and the other at the mouth of the Bronx River Estuary (BRE), during the summer and fall of 2011 and 2012. The es- timates of nitrogen (N) removal by Gracilaria over a 90-day growing season were up to 28 and 94 kg N ha �1 at theLISandBREsites,respectively.InJuly2012,Gracilariagrewupto16.5%day �1 atBREand 4.8% day �1 attheLIS site. Tissue N contents at the same periods were 3.7% (BRE) and 1.5% (LIS), respectively. These results demon- strate rapid assimilation of nutrients fueling the growth of new Gracilaria tissue at the BRE site, while nutrients appeared to limit growth at the LIS site during the summer months. The estimated C removal by Gracilaria at the BRE and LIS sites were up to 300 kg ha �1 (LIS) and 727 kg ha �1 (BRE), respectively. The potential economic values of N and C sequestration for the period examined in this study were as high as $311 (LIS) and $940 ha �1

Quantifying Feeding Behavior of Ribbed Mussels (Geukensia demissa) in Two Urban Sites (Long Island Sound, USA) with Different Seston Characteristics

The Atlantic ribbed mussel, Geukensia demissa, is found in salt marshes along the North American Atlantic Coast. As a first step to study the possibility of future cultivation and harvest of ribbed mussels for nutrient removal from eutrophic urban environments, the feeding behavior of ribbed mussels in situ was studied from July to October 2011. Two locations approximately 80 km apart were used as study sites: Milford Harbor (Connecticut; 41°12′42.46″N, 73°3′7.75″W) and Hunts Point (Bronx, New York; 40°48′5.99″N, 73°52′17.76″W). Total particulate matter was higher at Hunts Point than at Milford Harbor, but the organic content was higher at Milford than at Hunts Point. The relatively low quantity of organic content in Hunts Point seston resulted in a much higher production of pseudofeces by mussels. Mussel clearance and absorption rates were higher at Milford Harbor than at Hunts Point. Nevertheless, mussels at both sites had the same absorption efficiency, suggesting that mussels are able to adapt to conditions at both locations. Ribbed mussels decreased clearance rate when the seston quantity was high at both sites. At Hunts Point, ribbed mussels increased the gut transit time of ingested particles when the amount of inorganic particulates in the water increased. This study does not quantify nutrient removal capacity of G. demissa; however, the environmental tolerance demonstrated here, and current lack of commercial harvest, suggests that this species may be a good candidate for nutrient bioextraction in highly impacted urban environments.

Short communication: adaptability of the feeding behavior of intertidal ribbed mussels (Geukensia demissa) to constant submersion

The ribbed mussel (Geukensia demissa, Dillwyn 1817) is a dominant benthic filter-feeder in salt marshes along the North American Atlantic Coast. It has been proposed that the cultivation and harvest of ribbed mussels could be used to bioremediate the eutrophication of coastal waters. To accomplish this, mussels would be grown in suspension culture underwater, which is different than this species’ natural, intertidal habitat in which they are exposed to a tidal regime of submersion and emersion. To assess possible effects of constant submersion upon the feeding behavior of G. demissa, we quantified filter-feeding activities of ribbed mussels collected from either an intertidal location or a permanently submerged (2 months) population in the same embayment. Filtration measurements to determine clearance rates were conducted in aquaria containing ultra-filtered seawater with cultured phytoplankton. Results show that mussels taken from the intertidal population had significantly higher filtration than the submerged population initially, but after 3 days of submersion in the aquaria, this difference disappeared. Moreover, all experimental G. demissa had higher clearance rates during natural low tide than during natural high tide. These results indicate a potential for ribbed mussels to be grown in suspension culture for nutrient bioextraction purposes.