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Floyd M, East HK, Traganos D, Musthag A, Guest J, Hashim AS, Evans V, Helber S, Unsworth RKF, Suggitt AJ. Rapid seagrass meadow expansion in an Indian Ocean bright spot. Sci Rep 2024; 14:10879. [PMID: 38740840 DOI: 10.1038/s41598-024-61088-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 04/30/2024] [Indexed: 05/16/2024] Open
Abstract
The areal extent of seagrass meadows is in rapid global decline, yet they provide highly valuable societal benefits. However, their conservation is hindered by data gaps on current and historic spatial extents. Here, we outline an approach for national-scale seagrass mapping and monitoring using an open-source platform (Google Earth Engine) and freely available satellite data (Landsat, Sentinel-2) that can be readily applied in other countries globally. Specifically, we map contemporary (2021) and historical (2000-2021; n = 10 maps) shallow water seagrass extent across the Maldives. We found contemporary Maldivian seagrass extent was ~ 105 km2 (overall accuracy = 82.04%) and, notably, that seagrass area increased threefold between 2000 and 2021 (linear model, + 4.6 km2 year-1, r2 = 0.93, p < 0.001). There was a strongly significant association between seagrass and anthropogenic activity (p < 0.001) that we hypothesize to be driven by nutrient loading and/or altered sediment dynamics (from large scale land reclamation), which would represent a beneficial anthropogenic influence on Maldivian seagrass meadows. National-scale tropical seagrass expansion is unique against the backdrop of global seagrass decline and we therefore highlight the Maldives as a rare global seagrass 'bright spot' highly worthy of increased attention across scientific, commercial, and conservation policy contexts.
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Affiliation(s)
- Matthew Floyd
- Department of Geography and Environmental Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle Upon Tyne, NE1 8ST, UK.
| | - Holly K East
- Department of Geography and Environmental Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle Upon Tyne, NE1 8ST, UK
| | - Dimosthenis Traganos
- German Aerospace Centre (DLR), Remote Sensing Technology Institute, 12489, Berlin, Germany
| | - Azim Musthag
- Small Island Research Group, Faresmaathoda, 10780, Maldives
| | - James Guest
- School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK
| | - Aminath S Hashim
- Blue Marine Foundation, M. Beach Side, Handhuvaree Hingun, Malé, 20285, Maldives
| | - Vivienne Evans
- Blue Marine Foundation, Somerset House, Strand, London, WC2R 1LA, UK
| | - Stephanie Helber
- Department of Geography and Environmental Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle Upon Tyne, NE1 8ST, UK
| | - Richard K F Unsworth
- Seagrass Ecosystem Research Group, Faculty of Science and Engineering, Swansea University, Swansea, SA2 8PP, Wales, UK
| | - Andrew J Suggitt
- Department of Geography and Environmental Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle Upon Tyne, NE1 8ST, UK
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Zhang YH, Yu B, Liu YC, Ma W, Li WT, Zhang PD. The influence of decreased salinity levels on the survival, growth and physiology of eelgrass Zostera marina. MARINE ENVIRONMENTAL RESEARCH 2022; 182:105787. [PMID: 36368210 DOI: 10.1016/j.marenvres.2022.105787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 10/04/2022] [Accepted: 10/22/2022] [Indexed: 06/16/2023]
Abstract
Low salinity generally promotes the growth and propagation of temperate seagrasses, but the appropriate range is unclear. We subjected shoots of eelgrass Zostera marina to different salinity levels [10, 15, 20, 25, 30 PSU (control)] for 6 weeks under controlled laboratory conditions. We measured eelgrass responses in terms of survivorship, growth, productivity, leaf pigmentation and carbohydrate concentrations. Survival analysis combined with growth assessment suggested that the optimal salinity range for the propagation of Z. marina shoots was 18-21 PSU. Structural equation model (SEM) analysis indicated that the promotion effect of decreased salinity levels on the survival and growth of Z. marina shoots mainly depended on the increase in chlorophyll content and the accumulation and synthesis of nonstructural carbohydrates. The carotenoid content and soluble sugar content of the aboveground tissues of Z. marina shoots exposed to 20 PSU were 1.1 and 1.6 times higher than those of shoots under the control, respectively. The results will provide valuable data that could prove helpful in the development of efficient artificial propagation technology for Z. marina shoots.
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Affiliation(s)
- Yan-Hao Zhang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China
| | - Bing Yu
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China
| | - You-Cai Liu
- Hydrogeology and Engineering Geology Survey Institute, Geology and Mineral Exploration Bureau of Hebei Province, Shijiazhuang, People's Republic of China
| | - Wang Ma
- Hydrogeology and Engineering Geology Survey Institute, Geology and Mineral Exploration Bureau of Hebei Province, Shijiazhuang, People's Republic of China
| | - Wen-Tao Li
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China
| | - Pei-Dong Zhang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China.
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Zhang YH, Wang HH, Li F, Sun J, Li WT, Zhang PD. The combined effect of planting density and sediment fertilization on survival, growth and physiology of eelgrass Zostera marina. MARINE POLLUTION BULLETIN 2022; 184:114136. [PMID: 36155412 DOI: 10.1016/j.marpolbul.2022.114136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 09/07/2022] [Accepted: 09/10/2022] [Indexed: 06/16/2023]
Abstract
We subjected shoots of eelgrass Zostera marina to different combinations of planting density [300 (control), 450, 600, 750, 900 shoots m-2] and sediment fertilization [0 (control), 35, 70, 105, 140 g m-2] for 6 weeks under controlled conditions. We measured eelgrass responses in terms of survivorship, growth, productivity, leaf pigmentation and carbohydrate concentrations. The ramet frequency of Z. marina reached 47.8 % when exposed to the combination of 600 shoots m-2 and 70 g m-2, which was 3.2 times higher than that of shoots under the control. Survival analysis combined with growth assessment suggested that the optimal ranges of planting density and sediment fertilization for the propagation of Z. marina shoots were 501 to 530 shoots m-2 and 51 to 60 g m-2, respectively. The promotion of survival and propagation of Z. marina that stemmed from planting density and sediment fertilization mainly depended on the increase of chlorophyll content and accumulation of non-structural carbohydrate. The total chlorophyll content of Z. marina leaves exposed to the combination of 600 shoots m-2 and 70 g m-2 was 2.1 times higher than that of shoots under the control. The results will provide data that could prove helpful in the development of efficient artificial propagation technology for Z. marina shoots.
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Affiliation(s)
- Yan-Hao Zhang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China
| | - He-Hu Wang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China
| | - Fan Li
- Shandong Provincial Key Laboratory of Restoration for Marine Ecology, Shandong Marine Resources and Environment Research Institute, Yantai, People's Republic of China
| | - Jie Sun
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China
| | - Wen-Tao Li
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China
| | - Pei-Dong Zhang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, People's Republic of China.
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MacDonnell C, Bydalek F, Osborne TZ, Beard A, Barbour S, Leonard D, Makinia J, Inglett PW. Use of a wastewater recovery product (struvite) to enhance subtropical seagrass restoration. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:155717. [PMID: 35525357 DOI: 10.1016/j.scitotenv.2022.155717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 04/04/2022] [Accepted: 05/01/2022] [Indexed: 06/14/2023]
Abstract
Seagrasses are in decline worldwide, and their restoration is relatively expensive and unsuccessful compared to other coastal systems. Fertilization can improve seagrass growth in restoration but can also release nutrients and pollute the surrounding ecosystem. A slow-release fertilizer may reduce excessive nutrient discharge while still providing resources to the seagrass's rhizosphere. In this study, struvite (magnesium ammonium phosphate), a relatively insoluble, sustainable compound harvested in wastewater treatment plants, was compared to Osmocote™(14:14:14 Nitrogen: Phosphorus: Potassium, N:P:K), a popular polymer coated controlled release fertilizer commonly used in seagrass restoration. Two experiments compared the effectiveness of both fertilizers in a subtropical flow-through mesocosm setup. In the first experiment, single 0.5 mg of P per g dry weight (DW) doses of Osmocote™and struvite fertilizers were added to seagrass plots. Seagrass shoot counts were significantly higher in plots fertilized with struvite than both the Osmocote™and unfertilized controls (p< 0.0001). A significant difference in total P concentration was observed in porewater samples of Osmocote™vs struvite and controls (p< 0.0001), with struvite fertilized plots emitting more than controls (p ≤ 0.0001), but less than 2% of the total dissolved P (TDP) of Osmocote™fertilized plots (100+ mg/L versus x > 5 mg/L). A subsequent experiment, using smaller doses (0.01 and 0.025 mg of P per gram DW added), also found that the struvite treatments performed better than Osmocote™, with 16-114% more aboveground biomass (10-60% higher total biomass) while releasing less N and P. These results indicate the relatively rapid dissolution of Osmocote™may pose problems to restoration efforts, especially in concentrated doses and possibly leading to seagrass stress. In contrast, struvite may function as a slow-release fertilizer applicable in seagrass and other coastal restoration efforts.
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Affiliation(s)
- C MacDonnell
- University of Florida, Department of Soil, Water and Ecosystem Sciences, 1692 McCarty Drive, Gainesville, FL 32603, United States of America
| | - F Bydalek
- Department of Sanitary Engineering, Gdańsk University of Technology, 80-233 Gdansk, Poland
| | - T Z Osborne
- University of Florida, Department of Soil, Water and Ecosystem Sciences, 1692 McCarty Drive, Gainesville, FL 32603, United States of America; Whitney Laboratory for Biosciences, 9505 N Ocean Shore Blvd, St. Augustine, FL 32080, United States of America
| | - A Beard
- Whitney Laboratory for Biosciences, 9505 N Ocean Shore Blvd, St. Augustine, FL 32080, United States of America
| | - S Barbour
- University of Florida, Department of Soil, Water and Ecosystem Sciences, 1692 McCarty Drive, Gainesville, FL 32603, United States of America
| | - D Leonard
- University of Florida, Department of Soil, Water and Ecosystem Sciences, 1692 McCarty Drive, Gainesville, FL 32603, United States of America
| | - J Makinia
- Department of Sanitary Engineering, Gdańsk University of Technology, 80-233 Gdansk, Poland
| | - P W Inglett
- University of Florida, Department of Soil, Water and Ecosystem Sciences, 1692 McCarty Drive, Gainesville, FL 32603, United States of America.
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Menicagli V, Balestri E, Vallerini F, De Battisti D, Lardicci C. Plastics and sedimentation foster the spread of a non-native macroalga in seagrass meadows. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 757:143812. [PMID: 33246728 DOI: 10.1016/j.scitotenv.2020.143812] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 06/12/2023]
Abstract
Plastics are found in marine environments worldwide, and their effects on macrophytes (seagrasses and macroalgae) colonizing sandy bottoms are still poorly known. Seagrass meadows are valuable but declining ecosystems due to local and global-change related stressors, including sediment disturbance and introduced macroalgae. Understanding whether plastics pose a further threat to seagrasses is critically important. In two simultaneous additive experiments performed in an aquaculture tank, we examined the individual and combined effects of macroplastics (non-biodegradable high-density polyethylene and biodegradable starch-based) and sedimentation (no and repeated sedimentation) on the performance (in terms of biomass and architectural variables) of a native Mediterranean seagrass (Cymodocea nodosa) and an introduced macroalga (Caulerpa cylindracea), and on the intensity of their interactions. Macroplastics were still present in sediments after 18 months. Cymodocea nodosa produced a greater biomass and longer horizontal rhizome internodes forming clones with more spaced shoots probably to escape from plastics. Plastics prevented C. nodosa to react to sedimentation by increasing vertical rhizome growth. Under C. cylindracea invasion, C. nodosa allocated more biomass to roots, particularly to fine roots. In the presence of C. nodosa, C. cylindracea performance was reduced. High-density polyethylene (HDPE) plastic and sedimentation shifted species interactions from competitive to neutral. These results suggest that both HDPE and biodegradable starch-based macroplastics, if deposited on marine bottoms, could make seagrasses vulnerable to sedimentation and reduce plant cover within meadows. HDPE plastic and sedimentation could contribute to the decline of seagrass habitats by facilitating the spread of non-native macroalgae within meadows. Overall, the study highlights the urgent need to implement more effective post-marketing management actions to prevent a further entering of plastics in natural environments in the future, as well as to establish to conservation measures specifically tailored to protect seagrass habitats from plastic pollution.
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Affiliation(s)
- Virginia Menicagli
- Department of Biology, University of Pisa, via Derna 1, 56126 Pisa, Italy
| | - Elena Balestri
- Department of Biology, University of Pisa, via Derna 1, 56126 Pisa, Italy.
| | - Flavia Vallerini
- Department of Biology, University of Pisa, via Derna 1, 56126 Pisa, Italy
| | - Davide De Battisti
- Department of Biology, University of Pisa, via Derna 1, 56126 Pisa, Italy
| | - Claudio Lardicci
- Department of Earth Sciences, University of Pisa, via S. Maria 53, 56126 Pisa, Italy; Centre for Climate Change Impact, University of Pisa, Via Del Borghetto 80, Pisa 56124, Italy
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Balestri E, Vallerini F, Seggiani M, Cinelli P, Menicagli V, Vannini C, Lardicci C. Use of bio-containers from seagrass wrack with nursery planting to improve the eco-sustainability of coastal habitat restoration. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 251:109604. [PMID: 31569025 DOI: 10.1016/j.jenvman.2019.109604] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/09/2019] [Accepted: 09/16/2019] [Indexed: 06/10/2023]
Abstract
Traditional revegetation techniques employed to restore seagrass meadows and coastal dunes have recently been criticized for their impact on donor populations as well as for the installation of plant anchoring structures made of non-biodegradable or not natural materials in recipient habitats. To improve the ecological sustainability of restoration practices, a novel plantable biodegradable container made of beach-cast seagrass wrack and a bio-based polymer was produced. The long-term performance of two seagrasses, Cymodocea nodosa and Zostera noltei, and two dune plants, Euphorbia paralias and Thinopyrum junceum, grown in nurseries from seeds using the bio-container or a non-biodegradable container of equal size/form made of a conventional plastic (control) was also examined. In addition, the development of bio-container-raised C. nodosa plants in the field was compared to that of plants removed from control containers at the installation and anchored with a traditional system. The bio-container degraded slowly in seawater and in sand and lost its functionality after about three years. In nurseries, all the tested species grown in bio-containers performed as well as, or better than, those raised in non-biodegradable ones. Six months after transplanting into the field, 80% of the C. nodosa nursery-raised plants installed with their bio-container have colonized the surrounding substrate while most of those planted with the traditional system was lost. These results indicate that the new bio-container may support plant growth, and it may also provide protection and anchorage to plants in the field. The use of this bio-container in combination with nursery techniques could improve the environmental sustainability of coastal restoration interventions by providing large plant stocks from seed, thus reducing the impact of collection on donor populations. This approach would also limit the introduction of extraneous materials in recipient habitats and offer an opportunity for valorizing seagrass beach-cast material.
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Affiliation(s)
| | | | - Maurizia Seggiani
- Department of Civil and Industrial Engineering, University of Pisa, Italy
| | - Patrizia Cinelli
- Department of Civil and Industrial Engineering, University of Pisa, Italy
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El-Hacen EHM, Bouma TJ, Govers LL, Piersma T, Olff H. Seagrass Sensitivity to Collapse Along a Hydrodynamic Gradient: Evidence from a Pristine Subtropical Intertidal Ecosystem. Ecosystems 2019. [DOI: 10.1007/s10021-018-0319-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Alexandre A, Silva J, Santos R. Light Is More Important Than Nutrient Ratios of Fertilization for Cymodocea nodosa Seedling Development. FRONTIERS IN PLANT SCIENCE 2018; 9:768. [PMID: 29951074 PMCID: PMC6008371 DOI: 10.3389/fpls.2018.00768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 05/17/2018] [Indexed: 06/08/2023]
Abstract
Restoration of seagrass beds through seedlings is an alternative to the transplantation of adult plants that reduces the impact over donor areas and increases the genetic variability of restored meadows. To improve the use of Cymodocea nodosa seedlings, obtained from seeds germinated in vitro, in restoration programs, we investigated the ammonium and phosphate uptake rates of seedlings, and the synergistic effects of light levels (20 and 200 μmol quanta m-2 s-1) and different nitrogen to phosphorus molar ratios (40 μM N:10 μM P, 25 μM N:25 μM P, and 10 μM N:40 μM P) on the photosynthetic activity and growth of seedlings. The nutrient content of seedlings was also compared to the seed nutrient reserves to assess the relative importance of external nutrient uptake for seedling development. Eighty two percent of the seeds germinated after 48 days at a mean rate of 1.5 seeds per day. All seedlings under all treatments survived and grew during the 4 weeks of the experiment. Seedlings of C. nodosa acquired ammonium and phosphate from the incubation media while still attached to the seed, at rates of about twice of adult plants. The relevance of external nutrient uptake was further highlighted by the observation that seedlings' tissues were richer in nitrogen and phosphorus than non-germinated seeds. The uptake of ammonium followed saturation kinetics with a half saturation constant of 32 μM whereas the uptake of phosphate increased linearly with nutrient concentration within the range tested (5 - 100 μM). Light was more important than the nutrient ratio of fertilization for the successful development of the young seedlings. The seedlings' photosynthetic and growth rates were about 20% higher in the high light treatment, whereas different nitrogen to phosphorus ratios did not significantly affect growth. The photosynthetic responses of the seedlings to changes in the light level and their capacity to use external nutrient sources showed that seedlings of C. nodosa have the ability to rapidly acclimate to the surrounding light and nutrient environment while still attached to the seeds. C. nodosa seedlings experiencing fertilization under low light levels showed slightly enhanced growth if nourished with a balanced formulation, whereas a slight increase in growth was also observed with unbalanced formulations under a higher light level. Our results highlight the importance of high light availability at the seedling restoration sites.
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Affiliation(s)
- Ana Alexandre
- Marine Plant Ecology Research Group, Centre of Marine Sciences (CCMAR), University of Algarve, Faro, Portugal
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Campbell ML. Burial Duration and Frequency Influences Resilience of Differing Propagule Types in a Subtidal Seagrass, Posidonia australis. PLoS One 2016; 11:e0161309. [PMID: 27526020 PMCID: PMC4985149 DOI: 10.1371/journal.pone.0161309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Accepted: 08/03/2016] [Indexed: 11/19/2022] Open
Abstract
Sedimentation that leads to periodic, and often prolonged, burial events is becoming more common on the world's coastlines as human populations expand and create urbanised marine environments. Different seagrass species react differently to sediment burial but many species in the southern hemisphere are yet to be examined. How seagrasses react to burial has restoration implications. There is a need to critically assess seagrass transplant propagule responses to periodic (pulse) and prolonged (press) burial events before selecting the most appropriate species, transplant propagule, and transplant site. In my study, mesocosm experiments, coupled with field measurements were used to assess how sexual (seedlings) and vegetative (sprigs) propagules of Posidonia australis responded to pulse and press burial events. Seedlings were highly susceptible to burial (both pulse and press), with no survival at the end of the experimental period. In contrast, rhizome growth in vegetative propagules was stimulated by pulse burial, although press burial events resulted in mortality. The implication for Posidonia australis restoration efforts in areas where burial is periodic, was that vegetative propagules are optimal transplant units, in comparison to seedlings. Press burial however, renders a transplant site sub-optimal for both seedling and sprig transplants.
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Affiliation(s)
- Marnie L. Campbell
- School of Biological and Environmental Science, Murdoch University, Perth, Western Australia, Australia
- The Environmental Research Institute, University of Waikato, Hamilton, Waikato, New Zealand
- * E-mail:
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Bayraktarov E, Saunders MI, Abdullah S, Mills M, Beher J, Possingham HP, Mumby PJ, Lovelock CE. The cost and feasibility of marine coastal restoration. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:1055-74. [PMID: 27509748 DOI: 10.1890/15-1077] [Citation(s) in RCA: 211] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Land-use change in the coastal zone has led to worldwide degradation of marine coastal ecosystems and a loss of the goods and services they provide. Restoration is the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed and is critical for habitats where natural recovery is hindered. Uncertainties about restoration cost and feasibility can impede decisions on whether, what, how, where, and how much to restore. Here, we perform a synthesis of 235 studies with 954 observations from restoration or rehabilitation projects of coral reefs, seagrass, mangroves, salt-marshes, and oyster reefs worldwide, and evaluate cost, survival of restored organisms, project duration, area, and techniques applied. Findings showed that while the median and average reported costs for restoration of one hectare of marine coastal habitat were around US$80000 (2010) and US$1600000 (2010), respectively, the real total costs (median) are likely to be two to four times higher. Coral reefs and seagrass were among the most expensive ecosystems to restore. Mangrove restoration projects were typically the largest and the least expensive per hectare. Most marine coastal restoration projects were conducted in Australia, Europe, and USA, while total restoration costs were significantly (up to 30 times) cheaper in countries with developing economies. Community- or volunteer-based marine restoration projects usually have lower costs. Median survival of restored marine and coastal organisms, often assessed only within the first one to two years after restoration, was highest for saltmarshes (64.8%) and coral reefs (64.5%) and lowest for seagrass (38.0%). However, success rates reported in the scientific literature could be biased towards publishing successes rather than failures. The majority of restoration projects were short-lived and seldom reported monitoring costs. Restoration success depended primarily on the ecosystem, site selection, and techniques applied rather than on money spent. We need enhanced investment in both improving restoration practices and large-scale restoration.
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