Provisioning services of seagrass ecosystem in Pari Island

Seagrass ecosystem provides many ecosystem services, including provisioning services in which people obtain direct products (e.g., food) from the ecosystem. This study examined the seagrass ecosystem provisioning service in Pari Island, Jakarta Bay. The data was collected in May 2021 using questionaries from 97 respondents (40 fishers and 57 non-fishers) living on the island. Our analysis reveals that seagrass ecosystems around Pari Island deliver food sources and income for the local communities. Many species of fishes, shellfishes, shrimps, and swimming crabs are commonly harvested by the local community. The most dominant harvested fishes are rabbitfishes (Siganus spp, 85%) and emperor fishes (Lethrinus sp, 15%), while the harvested shellfishess are “kerang bulu” (Anadara spp, 42%), “buol” (Venus sp, 32%), and “kere-kere” (Grafrarium spp, 26%). The locals use fishing gear such as nets and handlines to catch fish and use knives, machetes, and crowbars to collect shellfish. Generally, the locals harvest biota in seagrass ecosystems 1-2 times per week, with a time of about 1-2 hours. The harvested biotas serve as protein sources; only a few community members sell it for livelihood. In conclusion, the provisioning services of seagrass ecosystems is manifested as a food sources and livelihood to the local communities.


Introduction
Seagrass ecosystem provides a number of ecosystem services, one of which is provisioning services [1].Provisioning services are products that humans directly use from the ecosystems, i.e., food, raw material, genetic resources, medicine, and energy.For example, Thallassia hemprichii leaves are very strong in inhibiting the free radicals and contain tremendous potential for utilization as a source of natural antioxidants [2].Many biotas are harvested from seagrass ecosystem and used for consumption or livelihood, such as fishes, sea cucumbers, swimming crabs, shellfish, squids, and seahorses [3,4,5,6,7,8,9,10,11].
Evidence shows that provisioning services are important sources of food and livelihoods for communities, especially those living on small islands [4,5,10,12,13].These communities is highly dependent on resources from seagrass ecosystems, which means that humans have a very close relationship with seagrass ecosystems.Seagrass ecosystems serve as fishing grounds, where local communities harvest biotas, and often as an area for seaweed cultivation [3,14].The fishers tend to catch biota in seagrass ecosystem, for example, in Chwaka Bay, East Afrika (70.93%), and Wakatobi (68%) [4,3].Fishing in the seagrass ecosystem is an effective, harmless, and easy choice [14].In addition, the dependency of fishers on the seagrass ecosystem is relatively high [9].Locals in Wakatobi, almost 70% harvest seagrass-associated fishes for consumption [4].Those prove that seagrass ecosystems are food security for the local community, mainly those living on small islands [6,12,13].
Provisioning and regulating services delivered by seagrass ecosystems have increasingly received more attention from the research communities, indicating an increasing acknowledgment of the benefit of seagrass ecosystems for social welfare.It will assist in developing a marine policy framework [15].Our study aims to investigate the provisioning services of the seagrass ecosystem on Pari Island.This study's result is essential to raise public awareness of the necessity of seagrass ecosystems, especially for those living on a small island like Pari Island.The result is also important as basic information required to manage the seagrass ecosystems on the island better.

Methodology 2.1. Studi location
Pari Island is situated in Jakarta Bay, Indonesia (05°50' -05°53' S; 106°34'-106°38' E).It is the main island of the Pari Islands groups.The area extent of this island is 41.32 ha [16], of which 40% was for housing settlement, 50% for tourism area, and the rest for other use (connectivity, etc.).This island harbors fewer than 300 families, most of whom work as fishermen and in tourism (Sahrul-the village head-personal communication, 2021).
Coral reefs, seagrass beds, and mangrove forests were characteristic of the coast of Pari Island [17,18,19].Mangrove habitat extent, based on Satelite Imagery WorldView-2 was 9.3 ha [20].The mangrove has a high percentage of canopy cover and stands density, so it was categorized as in very good condition [18].Meanwhile, the coral reef condition tends to be damaged but can still subsist and improve [17].Furthermore, seagrass habitat extent was 272,94 ha (in 2016).The seagrass condition was relatively stable, although there was some fluctuation in 2004-2016 [19].There were seven species, and Thallasia hemprichii was the dominant species [19].

Data collection
This study was a part of seagrass project conducted in 2021.Samples were collected in May 2021 using questionaries from 97 respondents (40 fishermen and 57 non-fishermen) who lived on the island.The non-fishermen respondent included housewives, government employees, tourism operators, and students.We assessed the utilization of seagrass-associated biota, frequency of utilization, purpose of utilization, and fishing gear using a structured questionnaire.Before conducting the interviews, we explained the study and its purpose to the head of the village and the elders, asking for permission.Besides questionnaires, we did in-depth interviews with the people who collect shellfish for livelihood.The gathered data were analyzed using simple statistics (frequency distributions and percentages) [21].

Fishing activities
Previous study showed that all respondents consisted of males (61%) and females (39%) and was dominated by the age ranging from 30-50 years (61%) [10].All fishermen were male, while women involved in harvesting invertebrates and selling shellfish.Further, a majority of the respondents went for fishing twice a week (1-2 times per week, see Figure 2a) for more than 3 hours (Figure 2b).They use small boats without motorized machines for fishing.They collect seashells on foot.The respondents use simple fishing gear to catch biota in the seagrass ecosystem.They use handlines, nets to catch fish, knives, machetes, and crowbars to harvest shellfishes.This situation is the same as it occurs in Bintan, Wakatobi, Derawan, Kei Kecil Island, and Youtefa Bay [9,10,11,22,7].

Utilization of biota from seagrass ecosystem in Pari Island
Seagrass-associated biota harvested by the local community varies, but shellfish are the most common (Figure 2d).We found 13 species of shellfishes, of which three are used for daily food consumption (Grafrarium sp, Anadara sp, Amusium sp) and are commercially valuable (Venus sp, Tapes literatus, Panopea sp, Anadara sp).Fish caught from seagrass ecosystems are dominated by Siganidae family, followed by Lethrinidae family which are common residents of the seagrass ecosystem [13,9].Biota harvested from the seagrass ecosystem in Pari Island (Figure 3) is not only for consumption but also supporting the livelihood of the local community.They usually sell the harvested biota during the weekend because many tourists come to Pari Island.Shellfishes are sold at IDR5,000/bowl, rabbitfishes at IDR15,000/kg, and squids at IDR35,000/kg.Meanwhile, shellfishes with higher economic value are sold to a supplier in Tanjung Kait or Kali Adem, Jakarta.Based on the in-depth interview, Venus spp ("buol") are sold at IDR30,000/kg, Tapes literatus ("kerang madu") IDR15,000/kg and Panopea sp ("kerang batik") IDR10,000/kg.In addition to operating around Pari Island, the fishers also collect shellfishes from other neighboring islands.For collecting shellfishes, a fleet of fishers consisted of 10-15 people with an average catch of 100-150 kg/day, and there were 20 fishers specializing on shellfishes in Pari Island.

Provisioning services of seagrass ecosystem
Our study indicates that seagrass ecosystem in Pari Island contributes to the people's welfare, both as protein source and livelihood.This means that seagrass ecosystem have an significant role in the lives of the locals.However, they are unaware that their livelihood relies on the seagrass ecosystem.That situation is similar to the local community in Selayar, they understand the benefits and functions of seagrass, but they are unaware of the services they obtain from the seagrass ecosystem [23].While public awareness is important in supporting seagrass conservation action [24].Our study suggests that public dissemination related to provisioning services of seagrass ecosystems needs to be increased.
Seagrass-associated biota utilized by local communities varies from different locations in Indonesia (Table 1).The most common biotas are fish, shellfish, and crabs, also commonly utilized in Pari Island.While other biotas, e.g.seaweed, seahorses, sea cucumber, can be commonly found in seagrass ecosystem in Pari Island, they are not yet utilized by the locals.In other locations, these biotas are species target by the local communities.This opens new opportunities for the local people in Pari Island to expand their species target to be harvested.Along with population growth, the demand for protein sources will increase.Consequently, the exploitation of seagrass-associated biota will likely increase.

Seagass ecosystem management challenges
The availability of seagrass provisioning services is highly dependent on the biophysical conditions and utilization patterns that occur in the ecosystem.A healthy seagrass ecosystem will provide provisioning services in higher quantities.In other words, the condition of damaged seagrass ecosystems will reduce the provisioning services of these ecosystems [26].Meanwhile, the pattern of utilization driven by purely economic interests would also affect the availability of provisioning of seagrass ecosystem services [10].Seagrass ecosystems in Pari Island are facing relatively high pressures, especially from anthropogenic activities.Tourism growth spurred resort development and reclamation on Pari Island [17,18].These activities can reduce water quality by increasing water turbidity, triggering seagrass loss.In addition, the large number of tourists will put pressure on the beach area, such as the activity of tourists walking on the beach and stepping on seagrass.Based on the information provided by the local association of homestay management, the number of tourists visiting the island can reach up to 2000 visitors during weekend.In line with the development of tourism, the collection of biotas such as fishes and shellfishes will also increase.This situation likely would affect seagrass ecosystems on Pari Island.Hence, more actions are needed to protect the seagrass ecosystem in this location.
Seagrass restoration could help sustain the provisioning services of seagrass ecosystem.However, seagrass restoration is generally laborious and costly [27], but it can be cheaper by involving the local communities during the project implementation [28].The previous study found that the communities are willing to participate in the seagrass restoration program voluntarily [10]; this is a profitable social asset.Therefore, to protect the provisioning services of the seagrass ecosystem and provide economic benefits to the locals, we propose to: 4.2.1.Developing seagrass marine ecotourism.Seagrass ecotourism has not been developed in Indonesia; even if there is, it is still part of beach-based tourism activities [9].However, seagrass ecotourism can be developed in line with the development of tourism activity on Pari Island [17,18].Ecotourism activities in seagrass meadows can be stand-alone or integrated with other tourism packages.Some attractions that can be developed by the community and have an impact on the economy are: 4.2.1.1.Seagrass Planting.Tourists are welcome to plant seagrass shoots and give a name to the seagrass planted with the hope that tourists will come back to see the planting results in the future.Thus the economic well of ecotourism continues to spin.This kind of attraction has never been done in seagrass, but it is not new as it has already been practiced in mangrove and coral-based tourism activities.

Seagrass
Seedling.Planting attractions such as point 4.2.1.1.will certainly require seagrass seeds.This becomes an opportunity for the local community to set up seagrass nurseries.Seagrass seedlings from the nurseries are then sold to tourists for seagrass transplantation.

Establish fishing quota for the harvesting of seagrass-associated biota.
The growing tourism activities in Pari Island will increase biota collection in the surrounding waters.Therefore, it is necessary to determine the carrying capacity and establishment of fishing quota to maintain the provisioning services of seagrass ecosystem.Fishing quota determination must be based on scientific information and should be communicated with all stakeholders to eliminate potential conflicts in the future.

Develop regulations related to seagrass ecosystem.
Any effort to manage seagrass ecosystems, especially provisioning services, will be meaningless if enforced by law and regulation do not enforced [15].The role of fishers and government could be critical to raising awareness and supporting the community's efforts to manage the seagrass ecosystem [29].Therefore, regulations at the village or district level are important.

Conclusion
Many species of fish, shellfish, shrimps, and swimming crabs are typical biota harvested by the local community on Pari Island.The most dominant harvested fishes are rabbitfish (Siganus spp; 85%) and emperor (Lethrinus sp; 15%), while shellfishes are "kerang bulu" (Anadara spp; 42%), "buol" (Venus sp; 32%), and "kere-kere" (Grafrarium spp; 26%).Our study shows that the provisioning services of seagrass ecosystems manifest in food sources and livelihood to the local communities on Pari Island.The seagrass ecosystem provisioning services can be maintained by restoration, ecotourism based on the seagrass ecosystem, imposing fishing quotas, and establishing local regulations.

Author statement
Nurul Dhewani Mirah Sjafrie was the main contributor, while Udhi Eko Hernawan, Firman Zulpikar, Triyono, and Susi Rahmawati contributed as the associate contributors.All authors approved the final manuscript.

Figure 1 .
Figure 1.Map of location

Figure 2 .
Figure 2. Fishing activities profile in Pari Island

Table 1 .
Provisioning services of the seagrass ecosystem in Indonesia