Seagrass Management Research Articles

Seagrass Ecosystems in Eastern Indonesia: Status, Diversity, and Management Challenges

Seagrass beds have roles and benefits in shallow water ecosystems, including producers of organic matter, habitats for various marine biota, and providing services that are beneficial for the fishing community. However, increasing development activities in coastal areas, have decreased their valuable roles, which also affects damage in seagrass beds in Indonesian waters. Therefore, information on species diversity and seagrass conditions, especially in East Indonesian waters, is needed. This paper aims to provide information as the initial study of the distribution of species diversity, conditions of seagrass beds, and challenges of seagrass management in eastern Indonesia. This study collected primary and secondary data from several data sources from seagrass monitoring and research activities. The assessment of conditions and categories of seagrass cover refers to the Decree of the state minister for the Environment (KMN-LH) of 2004 No. 200 and the 2017 seagrass monitoring guidelines. As a result of 24 monitoring locations ten species were found indicating that Eastern Indonesia has high species diversity. The results at 24 locations can be categorized as healthy seagrass conditions in six locations (25%) and around 16 locations (67%) as less healthy. Monitoring results after 2015 are predicted to change the diversity and seagrass conditions. The challenges of seagrass management in Eastern Indonesian waters, including the coastal environment changes, need to increase public knowledge and understanding of the role, function, and benefits of seagrass. Also, replanting and enhancement of seagrass-protected areas are essentially needed by the local government.

Bibliometric Analysis and Ecological Challenges in the Era of Climate Change for Seagrass Conservation Research in Indonesia

Seagrass ecosystems in Indonesia provide essential ecological services, including carbon sequestration, marine biodiversity support, and coastal protection. However, these ecosystems face significant threats from human activities, climate change, and pollution. This study was conducted due to the lack of comprehensive analysis on seagrass conservation research trends in Indonesia, aiming to address this gap and provide insights that can enhance conservation strategies. This study utilizes bibliometric analysis to examine research trends in seagrass conservation in Indonesia from 2007 to 2024, identifying 118 publications with an annual growth rate of 18.53%. Key research topics include biodiversity conservation, seagrass roles in climate change mitigation, and the management of protected areas. This analysis highlights the need to address research gaps, such as limited studies on community-based conservation approaches and the impact of local policies on seagrass management. The findings indicate a growing awareness of seagrass functions, such as carbon storage and support for fisheries, but highlight ongoing challenges related to limited financial resources and public awareness. By applying bibliometric analysis, this study provides a crucial tool for evidence-based decision-making, enabling more targeted and effective conservation policies. Community perceptions and participation, especially through community-based conservation initiatives, are crucial for the success of seagrass conservation efforts. This study uniquely contributes to the field by offering a clear map of research trends and gaps, guiding future research and policy to more effectively address seagrass conservation challenges in Indonesia. The study emphasizes the need for adaptive management strategies and collaboration among stakeholders to overcome the challenges of seagrass conservation in Indonesia.

Mapping fine-scale seagrass disturbance using bi-temporal UAV-acquired images and multivariate alteration detection

Seagrasses provide critical ecosystem services but cumulative human pressure on coastal environments has seen a global decline in their health and extent. Key processes of anthropogenic disturbance can operate at local spatio-temporal scales that are not captured by conventional satellite imaging. Seagrass management strategies to prevent longer-term loss and ensure successful restoration require effective methods for monitoring these fine-scale changes. Current seagrass monitoring methods involve resource-intensive fieldwork or recurrent image classification. This study presents an alternative method using iteratively reweighted multivariate alteration detection (IR-MAD), an unsupervised change detection technique originally developed for satellite images. We investigate the application of IR-MAD to image data acquired using an unoccupied aerial vehicle (UAV). UAV images were captured at a 14-week interval over two seagrass beds in Brisbane Water, NSW, Australia using a 10-band Micasense RedEdge-MX Dual camera system. To guide sensor selection, a further three band subsets representing simpler sensor configurations (6, 5 and 3 bands) were also analysed using eight categories of seagrass change. The ability of the IR-MAD method, and for the four different sensor configurations, to distinguish the categories of change were compared using the Jeffreys-Matusita (JM) distance measure of spectral separability. IR-MAD based on the full 10-band sensor images produced the highest separability values indicating that human disturbances (propeller scars and other seagrass damage) were distinguishable from all other change categories. IR-MAD results for the 6-band and 5-band sensors also distinguished key seagrass change features. The IR-MAD results for the simplest 3-band sensor (an RGB camera) detected change features, but change categories were not strongly separable from each other. Analysis of IR-MAD weights indicated that additional visible bands, including a coastal blue band and a second red band, improve change detection. IR-MAD is an effective method for seagrass monitoring, and this study demonstrates the potential for multispectral sensors with additional visible bands to improve seagrass change detection.

Biodiversity as a Tool to Boost Seagrass Restoration Success

This publication reviews the importance of seagrass, major threats to seagrass, and ways in which seagrass species diversity and genetic diversity can positively impact seagrass management and restoration. Written by C. Spengler, Jamila Roth, and Laura K. Reynolds, and published by the UF/IFAS Department of Soil, Water, and Ecosystem Sciences, March 2024.

Seagrass Community Structure and Ecosystem Carbon Stocks Along the Shoreline of Semujur Island, Bangka Belitung Province, Indonesia

Seagrass meadows serve as vital blue carbon ecosystems, sequestering significant amounts of CO2 and playing a crucial role in climate change mitigation. Semujur Island, located in the Bangka Belitung Province, exemplifies numerous small Indonesian islands boasting extensive seagrass meadows lining their shores. This research seeks to (1) describe the community structure of seagrass on Semujur Island, (2) assess the carbon storage within the seagrass ecosystem, and (3) analyze the relationship between seagrass community structure and carbon reserves across three distinct sites. According to the results of this study, there are eight species of seagrass on Semujur Island, i.e., Cymodocea rotundata, Enhalus acoroides, Halodule uninervis, Halophila ovalis, Oceana serrulata, Syringodium isoetifolium, Thalassia hemprichii, and Thalassodendron ciliatum. Diversity indices varied among sites, ranging from 1.48 to 1.72. Species evenness indices varied between 0.83 and 0.92, while dominance indices varied between 0.20 and 0.28. The highest estimated carbon stock was obtained at the site dominated by the species H. uninervis (75.11 MgC/ha); followed by the site dominated by T. hemprichii (50.55 MgC/ha). The correlation between seagrass community structure, including density and coverage, and carbon stocks demonstrated a moderate positive correlation, with coefficients of 0.430 and 0.528, respectively (p<0.05). This research highlights the significance of integrating ecological dynamics into the management of seagrass ecosystems to enhance climate change mitigation efforts. Additionally, it offers valuable data as a reference for the restoration and conservation of seagrass ecosystems.

Towards Sustainable Management of Beach-Cast Seagrass in Mediterranean Coastal Areas

Marine environmental conservation and tourist exploitation are often in conflict, particularly where anthropogenic pressure is greatest, such as along the coasts of the Mediterranean Sea. A case in point is the accumulation of beach-cast seagrass, a typical feature of the Mediterranean Sea that is nowadays perceived as an “obstacle” to tourist activities and thus treated and removed as waste, leading to environmental impacts. In this paper, we analyzed the legislative context at the Mediterranean basin level and the contribution of twenty virtuous research projects related to the topic. In our opinion, the main benefits for the beach–dune ecosystem would be generated by the use of seagrass banquettes directly within the beach system (temporary displacement, creating beach walkways, dune consolidation), while their uses outside the beach system (agricultural and farm solutions—compost and bedding) should be considered as alternative solutions for a circular economy, in case of consistent biomass deposits along the shores. In this perspective, we support the “Ecological Beach” model which integrates most of the science-derived solutions addressed in this study. This model provides good practices that can be usefully spread and shared along Mediterranean coasts: to achieve this result, it is necessary to create a regional or Mediterranean network involving local communities and stakeholders.

Optimizing Seagrass Detection in Lampung Selatan: Leveraging Machine Learning Algorithms and Sentinel-2A Imagery

Seagrass beds are one of the coastal ecosystems that play an important role in maintaining the stability of blue carbon. However, high community activities threaten the existence of seagrass beds themselves. South Lampung Regency is one of the areas with considerable seagrass potential but the availability of distribution and density data is still minimal. This research aims to identify and map seagrass density as a first step for seagrass management. The data used in this research is Sentinel 2A multispectral image. Machine learning-based classification methods used are random forest (RF) and support vector machine (SVM) because these algorithms have a good ability to distinguish objects based on their features. This study uses a 2-level classification scheme, where level 1 consists of land, shallow sea, and deep-sea classes. Level 2 is the shallow marine bottom benthic habitat class. The type of seagrass found in this area is Enhalus acoroides. Based on the results of the analysis, low, medium, and high-density classes were obtained with an area of low around 20.12 ha, medium around 34.67 ha and high around 320.12ha with a total area of 374.91ha. RF has a higher overall accuracy of 88.00% while SVM accuracy is 84.00% so it can be concluded that Sentinel 2A images can be used to detect seagrass meadows.

Seagrass ecosystem services show complex spatial patterns and associations

Seagrass beds support rich biodiversity and provide a range of important ecosystem services, and thus widespread seagrass degradation and decline has prompted broader efforts to protect and restore these habitats. Limited resources for seagrass management and restoration could be better directed by leveraging information about the potential patterns of ecosystem service supply. However, compared to many terrestrial and marine ecosystems, the spatial patterns and relationships among different seagrass ecosystem services are still poorly understood. Focusing on the Florida Gulf Coast as a study system, we performed one of the first spatially explicit assessments of multiple ecosystem services provided by seagrass beds. We developed or modified existing spatial models for five ecosystem services: biodiversity enhancement, nursery habitat, blue carbon, recreation, and coastal protection, using a combination of empirical and model datasets. Using these spatial models, we identified key predictors and quantified the marginal effect of seagrasses on each service. Our models revealed that seagrasses significantly enhance the supply of multiple services, but that there was considerable spatial variation within and among these services, resulting in distinct hotspots where seagrasses are most valuable in providing different services. Contrary to the expectation that all seagrass services will be positively correlated with one another because they are strongly related to seagrass characteristics, we also found positive and negative associations among services, revealing the potential for both co-benefits and trade-offs associated with seagrass management decisions. Finally, we found that biodiversity was not a reliable proxy for most services, as is sometimes assumed, highlighting the need for direct assessments of seagrass services. Our findings emphasize the importance of considering distinct predictors of different ecosystem services when assessing potential delivery from seagrasses and other foundation species, especially when planning and prioritizing ecosystem conservation and restoration projects.

Structural complexity of seagrass and environmental variables as a determinant of fish larvae assemblages in tropical coastal waters: Implications for seagrass management and conservation

Anthropogenic activities including climate change affect the development of structural complexity in seagrass and the state of environmental variables. It remains unclear whether these variables, alone or in combination, have an important influence on fish larvae assemblages. This study examined the influence of the structural complexity of seagrass meadows and various environmental variables on fish larvae assemblages in tropical coastal waters of Tanga, Tanzania. The study was conducted in four Thalassia hemprichii dominated seagrass meadows from June 2019 to January 2021. Multiple regression analysis indicated that the structural complexity of seagrass (canopy height, seagrass cover, and shoot density) and environmental variables (dissolved oxygen, temperature and salinity) were the foremost predictors for fish larvae assemblages; abundance and richness (R2 = 0.75, p = 0.0185, R2 = 0.54, p = 0.0396, respectively). Based on these findings, the structural complexity of seagrass and environmental variables are both important determinants of fish larvae assemblages in tropical coastal waters. The findings suggest that reducing anthropogenic activities that affect the development of structural complexity of seagrass and negatively impact environmental variables in seagrass meadows through more effective governance would result in increased production of fish larvae in meadows and, as a result, increased fish recruitment in tropical coastal waters.

Developing seagrass index for long term monitoring of Zostera japonica seagrass bed: A case study in Yellow River Delta, China

Seagrass beds offer unique and vital ecological services as an important blue carbon ecosystem in coastal wetlands. Zostera japonica is an intertidal seagrass species native to eastern Asia and is one of the most widely distributed seagrass species in China. However, little is known on the long-term variations of Z. japonica extents. Automatic mapping method for Z. japonica seagrass beds is in urgent need to fill this knowledge gap. In this study, we proposed a new SeaGrass Index (SGI) for automatic and rapid mapping of Z. japonica based on time-series Landsat satellite imagery, aiming to alleviate the influence of tidal inundation and enhance the separability from other coastal cover types. The SGI considers both spectral and phenological characteristics of Z. japonica, as well as the spatial location of Z. japonica. We took the Yellow River Delta (YRD), China as our study area, where Z. japonica was first discovered and reported in 2015. Based on SGI, Z. japonica extents during 1985–2018 were extracted using multi-Otsu thresholding algorithm. Accuracy assessments based on field investigations and high-resolution imagery showed that SGI successfully separated seagrass beds from other cover types, especially intertidal salt marshes, with overall accuracies > 95%, producer’s accuracies > 90% and user’s accuracies > 94%. Our study provides the first long-term maps of seagrass beds in YRD. The area of Z. japonica showed large variations during 1985–2018, ranging from 149 ha in 2005–2006 to 1302.9 ha in 2011–2012. The spatial distribution of Z. japonica varied with the morphological change of the estuary caused by river channel shifts. Since 2011, Z. japonica seagrass beds have undergone area degradation due to the invasion of S. alterniflora. The area was only 332.3 ha in 2017–2018. Coastal erosion and extreme climate events such as drought and typhoon might also explain degradation of seagrass beds in YRD. We expect that the SGI will advance automatic and rapid mapping methods for intertidal seagrass beds, and the Z. japonica maps will provide a baseline data for restoration and management of seagrasses at regional scale.

A field experiment exploring disturbance‐and‐recovery, and restoration methodology of Zostera capensis to support its role as a coastal protector

Seagrass degradation in the western Indian Ocean is of serious concerns with numerous severe climate events that has impacted Mozambique, as well as South Africa in recent time, highlighting the need for re‐establishing these critical habitats. The following paper present a field experiment from Mozambique concerning disturbance‐and‐recovery effects of Zostera capensis, a highly impacted seagrass species in the region. We undertook trials mimicking disturbance of meadows in terms of digging to collect clams, a common practice in Maputo Bay. Our results indicated that once such anthropogenic impacts are halted, Z. capensis meadows restore itself after 12 months of impact exclusion. In addition, we also conducted seagrass restoration experiment using a manual method, the so‐called plug method which, demonstrated to improve the survival rate with 75%, which has large implications for seagrass transplantation projects that are both time consuming and financially costly. The results from this study will further guide the appropriate management to build the best practice in seagrasses meadows restoration and awareness. It is clear from this study that a combination of both impact exclusions and active restoration is bound for best results of seagrass management actions.

A regional and international framework for evaluating seagrass management and conservation

Seagrass meadows provide a range of key ecosystem services that are of high economic and societal value; seagrass meadows enhance biodiversity, provide food security through fisheries support, and are increasingly recognised for the role they play in mitigating climate change by the process of carbon sequestration. Whilst there is an increasing understanding of the global significance of seagrass habitats, the extent of these habitats is declining globally. The requirement to implement effective seagrass conservation and management strategies is thus becoming increasingly important. If the ambitions of the United Nations 2030 Agenda for Sustainable Development and the Sustainable Development Goals are to be achieved, then nations need ambitious and applicable marine conservation plans. This includes management and protection to vulnerable ecosystems such as seagrass meadows. This study aims to evaluate a range of seagrass management and conservation approaches identified in different geographic regions, using a critique framework developed from the United Nations Environment Programme 2020 report on seagrass “Out Of The Blue: The Value Of Seagrasses To The Environment And To People’. Using the framework, seagrass management in Scotland is used as a case study and compared nationally to the rest of the UK (England, Wales and Northern Ireland) and internationally, to Europe (Wadden Sea), Australia (Great Barrier Reef Marine Park) and West Africa (Senegal). The results identify potential areas of development in Scotland to enhance its seagrass conservation effort, including increased research in seagrass science, widespread mapping of seagrass, long-term monitoring programmes, improved marine protected areas, inclusion of seagrass protective measures into environmental laws and policies and the implementation of appropriate habitat restoration schemes. The results also identify the need for open data if effective knowledge sharing is to take place, and to ensure that ocean science can fully support countries to achieve the 2030 Agenda for Sustainable Development.

‘The public perception of the role, importance, and vulnerability of seagrass. A case study from the Great Barrier Reef’

Seagrass meadows, one of the world′s greatest natural assets, are globally declining due to direct-anthropogenic (e.g., pollution, coastal development, run-off) and climate change (e.g., cyclones, floods, marine heatwaves) threats. One of the primary constraints in seagrass management and restoration is a lack of societal awareness about their role in the marine environment, their importance to human well-being, and their vulnerability. Public perception studies are useful tools to assess communities′ ecological knowledge and attitudes. The Great Barrier Reef World Heritage Area (GBRWHA), famous worldwide for its iconic coral reef, also hosts one of the world′s largest areas of seagrass meadows, which provide many ecosystem services to the associated communities (e.g., nursery habitat, coastal protection, carbon sequestration etc.). However, the perception of seagrasses among coastal communities of the GBRWHA is poorly understood. Through an online survey of marine recreational users, we assessed public awareness of the role seagrasses play, its benefits, and threats to seagrasses in the GBRWHA, in comparison to coral reefs. Our results showed that there is an imbalance in perception of the role and ecosystem services provided by seagrasses and coral reefs among frequent visitors of the GBRWHA. Only 17% of respondents recognized ‘seagrass’ as a habitat of the GBRWHA. Ecosystem services from coral reefs were considered greater than from seagrasses (p < 0.05). Compared to previous studies, a higher percentage of participants believe in climate change (75%). Nevertheless, the general perception is that climate change impact magnitude is higher in coral reefs compared to seagrasses (p < 0.05). Additionally, climate change mitigation, a seagrass-related ecosystem service, was equally attributed to coral reefs and seagrasses (p > 0.05). Willingness-to-pay for coral reef restoration was higher than for seagrass (p < 0.05). For both marine habitats, willingness-to-pay for restoration was higher in younger people and participants with a university degree. Content analysis showed that people believe that marine habitats′ conservation/restoration can be achieved as a collective effort. On the other hand, a lack of trust in government actions was identified as a barrier to willingness-to-pay. These results confirm the need to raise awareness about the importance of seagrasses and of its vulnerability to climate change. To achieve that, we provide two key recommendations: to enhance purposeful experiences through citizen science and to increase effective scientific communication.

Komposisi dan biodiversitas padang lamun pada daerah konservasi dan non-konservasi di kawasan Sunda Kecil, Indonesia

Seagrass is one of the most productive plants in the marine ecosystems. Seagrass meadows provide many ecosystems services for marine organisms, yet there is growing evidence that seagrasses are experiencing declines globally due to anthropogenic threats. Although the study of seagrass in Indonesia has been widely caried out, Bali and Lombok have received little attention. Our study aimed to investigates the biodiversity of seagrass beds among different meadows characteristics in Bali and Lombok. This study was conducted at conservation area and non conservation area in Bali and Lombok, which were consists of total 8 sites. A total of 9 seagrass species were identified in this study, where 8 species found in Bali, both in conservation and non-conservation area, while in Lombok only 5 species found in conservation area and 6 species in non-conservation area. Most common species that found in this study were Enhalus acoroides, Cymodocea rotundata, Thalassia hemprichii, Halodule uninervis, and Halodule pinifolia. Analysis of similarity (ANOSIM) revealed there was no significant differences of seagrass density between sites in Bali and Lombok. Bray-Curtis dendogram showed the highest similarity found between NCA Lombok and CA Lombok (75 %), followed by NCA Bali and CA Bali (45 %). Implications of our study was to provide baseline study about the important of seagrass management, restoration, conservation, and protecting them due to anthropogenic pressure.

Sand supplementation favors tropical seagrass Thalassia hemprichii in eutrophic bay: implications for seagrass restoration and management

BackgroundSediment is crucial for the unique marine angiosperm seagrass growth and successful restoration. Sediment modification induced by eutrophication also exacerbates seagrass decline and reduces plantation and transplantation survival rates. However, we lack information regarding the influence of sediment on seagrass photosynthesis and the metabolics, especially regarding the key secondary metabolic flavone. Meanwhile, sulfation of flavonoids in seagrass may mitigate sulfide intrusion, but limited evidence is available.ResultsWe cultured the seagrass Thalassia hemprichii under controlled laboratory conditions in three sediment types by combining different ratios of in-situ eutrophic sediment and coarse beach sand. We examined the effects of beach sand mixed with natural eutrophic sediments on seagrass using photobiology, metabolomics and isotope labelling approaches. Seagrasses grown in eutrophic sediments mixed with beach sand exhibited significantly higher photosynthetic activity, with a larger relative maximum electron transport rate and minimum saturating irradiance. Simultaneously, considerably greater belowground amino acid and flavonoid concentrations were observed to counteract anoxic stress in eutrophic sediments without mixed beach sand. This led to more positive belowground stable sulfur isotope ratios in eutrophic sediments with a lower Eh.ConclusionsThese results indicated that coarse beach sand indirectly enhanced photosynthesis in T. hemprichii by reducing sulfide intrusion with lower amino acid and flavonoid concentrations. This could explain why T. hemprichii often grows better on coarse sand substrates. Therefore, it is imperative to consider adding beach sand to sediments to improve the environmental conditions for seagrass and restore seagrass in eutrophic ecosystems.

Using Unoccupied Aerial Vehicles (UAVs) to Map Seagrass Cover from Sentinel-2 Imagery

Seagrass habitats are ecologically valuable and play an important role in sequestering and storing carbon. There is, thus, a need to estimate seagrass percentage cover in diverse environments in support of climate change mitigation, marine spatial planning and coastal zone management. In situ approaches are accurate but time-consuming, expensive and may not represent the larger spatial units collected by satellite imaging. Hence, there is a need for a consistent methodology that uses accurate point-based field surveys to deliver high-quality mapping of percentage seagrass cover at large spatial scales. Here, we develop a three-step approach that combines in situ (quadrats), aerial (unoccupied aerial vehicle—UAV) and satellite data to map percentage seagrass cover at Turneffe Atoll, Belize, the largest atoll in the northern hemisphere. First, the optical bands of four UAV images were used to calculate seagrass cover, in combination with in situ data. The seagrass cover calculated from the UAV was then used to develop training and validation datasets to estimate seagrass cover in Sentinel-2 pixels. Next, non-seagrass areas were identified in the Sentinel-2 data and removed by object-based classification, followed by a pixel-based regression to calculate seagrass percentage cover. Using this approach, percentage seagrass cover was mapped using UAVs (R2 = 0.91 between observed and mapped distributions) and using Sentinel-2 data (R2 = 0.73). This work provides the first openly available and explorable map of seagrass percentage cover across Turneffe Atoll, where we estimate approximately 242 km2 of seagrass above 10% cover is located. We estimate that this approach offers 30 times more data for training satellite data than traditional methods, therefore presenting a substantial reduction in cost-per-point for data. Furthermore, the increase in data helps deliver a high-quality seagrass cover map, suitable for resolving trends of deteriorating, stable or recovering seagrass environments at 10 m2 resolution to underpin evidence-based management and conservation of seagrass.

Integrating sentinel-2 spectral-imagery and field data of seagrass coverage with species identification in the coastal of Riau Islands, Indonesia

Seagrass plays an important role in marine ecosystem. Plans for sustainable management of marine ecosystem should give due attention to this marine critical habitat. One effort to monitoring the long-term management of seagrass is to use spatial data using remote sensing techniques. Satellite imagery offers an efficient and cost-effective means of estimating water conditions in shallow environments. This study aims to map the coverage of the seagrass meadows using satellite images spatially, determine the species composition of the seagrass meadows, and examine the accuracy level from the results obtained by the Sentinel-2 images. Investigations reported here were conducted in the Riau Islands (4 Stations at Lingga Island and 2 Stations at Singkep Island) in Indonesia from 3 - 7 October 2020. The satellite image data used Sentinel-2 at the acquisition year of 2019 based on the method of Depth Invariant Index (DII) with Support Vector Machine (SVM) classification. The in situ observations were made from 6 October 2020, same with the validation date, to verify the data obtained through satellite imagery. This was needed for calculating the accuracy of results based on seagrass images and identifying the species using the Seagrass-Watch (Transect Quadrant). The result showed that the seagrass in the Riau Islands can be detected with the DII method with seagrass coverage area of 175 km2 from the satellite in Lingga and Singkep Island. Percentage of Seagrass coverage for all transects was estimated to be about 78%. The seagrasses species identified were: Halophila ovalis, Halophila minor, Thalassia hemprichii, and the dominant species was Enhalus acoroides.

Strategies to Improve Management of Indonesia’s Blue Carbon Seagrass Habitats in Marine Protected Areas

Indonesia’s seagrass habitats play an important role in the fight against climate change since they store a significant portion of the world’s blue carbon. Despite progress in conservation efforts and increasing number of Indonesia’s marine protected areas (MPAs), these habitats are generally still under multitude of pressures leading to declining condition. Thus, there is a growing need to improve the conservation management of seagrass habitats, especially within MPAs in Indonesia. Here, we identify five challenges on managing seagrass meadows in Indonesia’s MPAs: (1) Achieving societal awareness on the importance of seagrasses in Indonesia’ MPAs; (2) Achieving fair recognition from the management authority of Indonesia’s MPAs; (3) Obtaining political initiatives related to laws and regulations on seagrass management; (4) Providing empirical data on seagrass habitats at national level repeated over time; and (5) Enhancing capacity to conduct community-based management of seagrasses. Then, we propose a series of solutions to solve these challenges. We believe that all stakeholders need to work collaboratively to secure the future of Indonesia’s seagrass habitats and maintain their capacity to deliver significant ecosystem services.

Natural seagrass tribopositive material based spray coatable triboelectric nanogenerator

For the first time, this paper proposes natural seagrass based prominent ocean flowering and bio-friendly material for triboelectric nanogenerator (TENG) through a simple spray coating technique. Herein, two different seagrass species (Zostera marina and Phyllospadix japonicus) are effectively applied as a tribopositive material. Furthermore, spray coatable Phyllospadix japonicus seagrass film/PET TENG yields a higher power density of 70.42 μW/cm2 compared to Zostera marina seagrass film/PET TENG of 50.42 μW/cm2 because of the higher oxygen functional groups, which enables the device to offer increased electron-donating capability. Moreover, the output performance of the proposed spray coatable TENG device improved by about 31% compared to powder-based seagrass film. Furthermore, the Phyllospadix japonicus based TENG presents the extraordinary working stability up to 72,000 cycles (2 h), which confirms the excellent robustness of the fabricated device. It is further demonstrated that the proposed Phyllospadix japonicus based TENG can easily charge various commercial capacitors and capable of driving about 150 light-emitting diodes (LEDs), and other microelectronic devices. We anticipate that by applying seagrass as a tribopositive layer, the proposed spray coatable TENG device will serve its promising role for energy generation with extremely low fabrication cost. Furthermore, in addition to the economic use of seagrass as a TENG, this work can favorably contribute to sustainable seagrass management.

Alternative seagrass wrack management practices in the circular bioeconomy framework: A life cycle assessment approach

Despite providing important ecological functions, seagrass accumulation causes environmental and economic issues, including eutrophication and tourism reduction. Nowadays, seagrass wrack is commonly removed from the beaches and landfilled, which is considered the least desirable practice according to the European Union (EU) Waste Framework Directive. In this study, different management strategies for seagrass valorisation, including anaerobic digestion (AD), composting and ecological restoration, were considered using a life cycle assessment (LCA) perspective. The aim of the work was to evaluate more ecological and economic alternatives to landfill and to provide a robust evaluation method for public and private companies. An economic assessment was subsequently conducted, considering both direct and indirect impacts with a life cycle costing (LCC) approach. A selected beach located in the Northeast Mediterranean Sea was considered as a relevant case-study. The environmental impacts of the seagrass management scenarios were evaluated with the method ReCiPe 2016H, using both midpoint and endpoint levels. LCA results showed that ecological restoration and AD were the best alternatives in terms of environmental performances because of biogas production used as a renewable energy source. The impacts of the alternative management strategies were significantly lower than the current landfill strategy, -70% considering the categories of human health, ecosystems and resources, and -95% considering global warming potential category. The LCC analysis proved that composting was the best alternative (NPV > 1.27 M€), due to lower operating costs and higher fertilizer value. The obtained results can help beach management companies and public administrations to select the best operational strategies to reduce the environmental and economic impact of seagrass collection and treatment.