Rohani Ambo-Rappe

Translational Fluctuating Asymmetry and Leaf Dimension in Seagrass, Zostera capricorni Aschers in a Gradient of Heavy Metals

Methodology for measuring translational fluctuating asymmetry (TFA) on leaves of seagrass, Zostera capricorni Aschers has been developed and tested to detect a subtle effect of environmental stress associated with heavy metal pollution on developmental instability. Our analyses showed that concentration of heavy metals (Cd, Pb, Cu, Zn, Se) in leaves and roots of the seagrass were significantly higher in the polluted location than in relatively unpolluted locations. We found significant differences in TFA between different locations, showing that the method is sensitive enough to detect spatial differences even within a rather small water body, but these differences were not associated with a higher concentration of heavy metals, i.e. plants from the polluted location did not show higher TFA. Possibly, seagrass can store heavy metals in their tissues and protect their development from the toxic effect, or the effect of heavy metals in the natural environment is confounded by other environmental factors. At...

Developing a methodology of bioindication of human-induced effects using seagrass morphological variation in Spermonde Archipelago, South Sulawesi, Indonesia

Seagrass is particularly susceptible to environmental degradation. The objective of the study is to develop an effective bioindicator to assess human-induced effects using morphological variation and fluctuating asymmetry (FA) of seagrass. Samples were collected from eight islands situated at different distance from mainland with different human population density and therefore expected to experience different level of anthropogenic pressure. Cd, Pb, Cu, Zn, nitrate, and phosphate were measured. Metals were also measured in tissues of seagrass. Metal concentrations in sediment, water, and seagrass did not exceed the quality standards required for marine life. Heterogeneity of FA was found among sites suggesting that there are some factors changing developmental instability of seagrass which is not associated to particular toxicants. This baseline study indicates that the water condition is still natural and shows no signs of metal contamination, therefore it does not cause a detectable stress on morphological variation and FA of seagrass.

Regional Comparison of the Ecosystem Services from Seagrass Beds in Asia

Coastal ecosystems offer valuable services to human society. However, these ecosystems are facing multiple impacts of human-induced stress, including overexploitation, eutrophication, land construction, and global climate change. The prediction of long-term changes in coastal ecosystems under multiple impacts is difficult because nonlinear and cumulative effects operate simultaneously. This difficulty is especially true for Asian regions, where coastal biodiversity is the world’s highest but the least studied. In this chapter, we compare ecosystem services of coastal areas of Asia based on the expert knowledge of practioners who study coastal ecosystems at each locality. We especially focused on seagrass beds, which provide important services to humans including provision of seafood and regulation of water conditions. We selected the six most important ecosystem services at each of 13 seagrass beds ranging from Japan to India and evaluated the direction of changes over the past two decades. We also evaluated public awareness and data certainty for each service. Food provisioning, water purification and waste treatment, erosion regulation, recreation and ecotourism, and educational values were selected as major ecosystem services of seagrass beds. Degradation during the over past 10–20 years was reported for most provisioning and regulating services, whereas improving trend was found for cultural services in most sites. Public awareness and certainty of information were generally high for provisioning services, but low for most regulating services. Regional variation along latitude, and differences between temperate and tropical seagrass beds, were not detected for the examined variables. Regional comparisons of ecosystem services shed light on general and specific aspects of the status of seagrass beds, which will provide baseline data for planning effective conservation and management strategies under multiple human impacts.

Indonesia's globally significant seagrass meadows are under widespread threat

Indonesias marine ecosystems form a fundamental part of the worlds natural heritage, representing a global maxima of marine biodiversity and supporting the worlds second largest production of seafood. Seagrasses are a key part of that support. In the absence of empirical data we present evidence from expert opinions as to the state of Indonesias seagrass ecosystems, their support for ecosystem services, with a focus on fisheries, and the damaging activities that threaten their existence. We further draw on expert opinion to elicit potential solutions to prevent further loss. Seagrasses and the ecosystem services they support across the Indonesian archipelago are in a critical state of decline. Declining seagrass health is the result of shifting environmental conditions due largely to coastal development, land reclamation, and deforestation, as well as seaweed farming, overfishing and garbage dumping. In particular, we also describe the declining state of the fisheries resources that seagrass meadows support. The perilous state of Indonesias seagrasses will compromise their resilience to climate change and result in a loss of their high ecosystem service value. Community supported management initiatives provide one mechanism for seagrass protection. Exemplars highlight the need for increased local level autonomy for the management of marine resources, opening up opportunities for incentive type conservation schemes.

Marine Debris on Small Islands: Insights from an Educational Outreach Program in the Spermonde Archipelago, Indonesia

Marine debris is a global environmental problem especially apparent on small islands throughout the world. We implemented an educational outreach program to engage primary and secondary students in the scientific process using the tangible issue of marine debris on a typical small island in Indonesia (Barrang Lompo, Spermonde Islands, South Sulawesi). Over a three-year period, students conducted systematic sampling of debris on their islands beaches. They quantified the enormity of the debris problem, discussed data, and compared experiences with partner schools in California. The program inspired a unique, local perspective on marine debris that includes greater awareness of human health impacts as well as a need for realistic solutions to this problem faced by small islands.

Species richness accelerates marine ecosystem restoration in the Coral Triangle

Significance The exceptional diversity of species in the coral reefs, seagrass meadows, and mangrove forests of the Coral Triangle and the many ecological functions and benefits to humans they provide have made them a high priority for conservation and fisheries management. Nevertheless, their degradation continues and calls for effective restoration. In an experimental restoration, we demonstrated that planting mixtures of diverse seagrass species improves their overall survival and growth and thus the trajectory toward successful restoration. Incorporating species diversity into restoration heralds a shift in practice from establishing a single founder species, and recognizes the widely documented positive effects that biodiversity has on ecosystem function and services. Biodiversity is often a restoration goal, but it also promises a means to improve success. Ecosystem restoration aims to restore biodiversity and valuable functions that have been degraded or lost. The Coral Triangle is a hotspot for marine biodiversity held in its coral reefs, seagrass meadows, and mangrove forests, all of which are in global decline. These coastal ecosystems support valuable fisheries and endangered species, protect shorelines, and are significant carbon stores, functions that have been degraded by coastal development, destructive fishing practices, and climate change. Ecosystem restoration is required to mitigate these damages and losses, but its practice is in its infancy in the region. Here we demonstrate that species diversity can set the trajectory of restoration. In a seagrass restoration experiment in the heart of the Coral Triangle (Sulawesi, Indonesia), plant survival and coverage increased with the number of species transplanted. Our results highlight the positive role biodiversity can play in ecosystem restoration and call for revision of the common restoration practice of establishing a single target species, particularly in regions having high biodiversity. Coastal ecosystems affect human well-being in many important ways, and restoration will become ever more important as conservation efforts cannot keep up with their loss.

Species richness effects on the vegetative expansion of transplanted seagrass in Indonesia

Abstract Seagrass restoration is necessary to provide the critical ecosystem functions that are being lost with seagrass decline. Seagrass restoration of mixed species seagrass beds, especially in the Indo-Pacific Ocean, is poorly understood. Here, we transplanted random combinations of 1, 2, 4 and 5 seagrass species common in Indonesia to determine the effect of multispecies plantings on expansion of rhizomes. We measured seagrass vegetative expansion outside of the transplantation plots after 1 year post-transplantation for 5 months. The expansion rate increased with species richness. This result indicates that a multispecies approach to seagrass restoration in Indonesia would benefit restoration efforts. Further, for multispecies restoration we suggest using five-species combinations because they expanded the fastest of all species richness levels by the end of the experiment (on average 15.4 cm2 day−1).

Higher fluctuating asymmetry: indication of stress on Anadara trapezia associated with contaminated seagrass

Seagrasses are marine angiosperms that colonize near-shore environments. Concern has arisen over increasing concentrations of heavy metals in these systems resulting from industrial and urban development due to the ability of seagrass to accumulate trace metals from the environment without showing any impact on their productivity. This may pose a threat to a coastal community because the polluted seagrass will then provide a source of contamination to seagrass consumers. The main aim of this study was to determine whether there was any detectable effect of heavy metal pollution in seagrass on associated fauna. Fluctuating asymmetry of shell structure of a bivalve, Anadara trapezia, were employed as biomarkers for this environmental study. The result from this study revealed that A. trapezia showed distinct morphological characters and high shell asymmetry in the polluted location. Thus, A. trapezia associated with seagrass may be responsive to heavy metal stress and possibly a good indicator of heavy metal pollution in this system. The present study discusses the possibility of using a more cost-effective biomarker to define areas of heavy metal pollution.

“The Lost Princess (putri duyung)” of the Small Islands: Dugongs around Sulawesi in the Anthropocene

In the Spermonde as in the other main island groups around Sulawesi, seagrass and coral ecosystems are intimately linked ecologically and overlap extensively on the shallow water shelves surrounding most islands. One keystone species living in these shallow waters is the dugong (Dugong dugon). Officially fully protected under Indonesian Law (PP7/1999), published data on dugongs in the islands around Sulawesi are extremely limited. In this research, we collected, compiled and evaluated data and information (mostly unpublished) on the distribution, exploitation and community perceptions of dugongs around Sulawesi, including the Togean, Banggai, Spermonde, Taka Bone Rate/Selayar and Tanakeke Islands. Opportunities for dugong conservation, and potential benefits for coral reef ecosystems in a small island socio-ecological context, were considered. Once common within living memory, socio-economic data indicate that Sulawesi dugongs are now rare and under severe threat. Many fishing communities consider dugong meat superior to beef, and see it as a welcome change from fish, while certain body parts fetch a high price, as do dugong tears. In the Spermonde Islands, dugongs may already have been extirpated; the most recent reported sighting was in 1993 when the capture of an adult dugong by fishermen of Barranglompo Island resulted in an impromptu festival. All these Sulawesi small islands communities have dugong princess (putri duyung) legends with potential as an entry-point to hearts and minds. Preventing further extirpations and striving to bring back the “lost princess” could be an iconic component of moving towards sustainability in small-island socio-ecological systems.

Hydrodynamics in Indo-Pacific seagrasses with a focus on short canopies

Abstract Seagrass hydrodynamic regimes are important to understand and also to guide seagrass restoration, which is of great interest in Indonesia because of environmental threats to the exceptionally high seagrass species richness. Hydrodynamic regimes influence the physical stability of seagrass beds, sedimentation rates, and the advection of nutrients and food to seagrasses and associated organisms. In a flume, we determined the effect of canopies of Cymodocea rotundata, Enhalus acoroides, Halodule uninervis, Syringodium isoetifolium and Thalassia hemprichii on water velocity, turbulence, turbulence intensity and shear velocity. The taller canopies of Enhalus and Cymodocea slowed water flow, but the shorter canopies (<5 cm) had little effect. Seagrasses did not influence turbulence and turbulence intensity (turbulence normalized to mean velocity) but they reduced shear velocity U*. Our results indicate that Enhalus is a good candidate for transplantation in terms of reducing mean water flow and shear velocities, but that Halodule should also be considered as it also reduced shear velocities and it spreads quickly after transplantation. Our results extend the understanding of seagrass-hydrodynamic relationships to include very short canopies, unlike the taller canopies studied to date.