Identification of River Ecosystem Services through Water Utilization at Merapi Volcano, Indonesia

Merapi volcano is renowned as one of the world’s most active and densely populated volcanoes. Despite the constant high risk it presents, local residents continue to inhabit the Merapi slopes, primarily due to the ecosystem services that sustain their lives. River ecosystem services in this area are particularly vulnerable to landscape changes, largely driven by volcanic eruptions and human activities. This study aims to define the river ecosystem services by exploring the water utilization in Krasak River, which has been affected by Merapi eruptions from 2010 to 2023. The evaluation of water utilization was conducted using an ecosystem services approach, involving semi-structured interviews with 42 informants in six villages located along the upstream, middle stream, and downstream of the Krasak River. Content analysis was employed to explore water utilization practices and categorize river ecosystem services. The results revealed that water utilization in Krasak watershed comprises the use of springs and wells for supplying drinking needs and domestic needs as well as the use of rivers for irrigation water, fish ponds and recreation activities. Variations in Krasak River water utilization in different segments were influenced by water quality, quantity, accessibility, and the availability of alternative water sources. Based on local perspectives, the prominent river services encompass provisioning (e.g., irrigation, fish ponds, rural water supply, sand and stones), regulating (e.g., water quality maintenance, groundwater quantity), supporting (e.g., primary productivity), and cultural (e.g., recreation, aesthetic value) services. Challenges to river ecosystem services include concerns about river water utilization’s impact on perceptions of the river’s value and the roles of local communities and government in Krasak River management. These findings would contribute valuable insights for enhancing sustainable water resource management in the Merapi area.


Introduction
Water is the foundation of sustainable development, yet it can also spark conflicts due to its limited availability [1] which leads to competition for access to this vital resource [2].On a global scale, there are still issues regarding basic water service, water scarcity and unequal access, environmental degradation, climate change, water pollution, sanitation, water-related natural disasters, growing urbanization and lack of integrated management [3,4].
In alignment with SDG Goal 6, which emphasizes the universal access to clean water and sanitation, effective water management, Indonesia's commitment in the Water Action Agenda 2023 is fulfilling water needs especially to overcome poverty and food crisis as essential aspects for sustainable development.The unique geographical settings of Indonesia, shaped by its 129 active volcanoes, complicate water-related issues more than expected, given the existence of disaster-prone areas and cascading hazards.Given the distinct geological and hydrological characteristics of volcanic areas, it becomes imperative to adopt a holistic perspective in managing water resources [5,6].This involves the coordinated management of various aspects, such as sourcing, distribution, purification, and conservation of water resources [7].This holistic approach acknowledges that issues like water scarcity, contamination risks, and susceptibility to volcanic hazards are interconnected and need to be addressed collectively [1,8,9].By placing integration at the forefront, Indonesia can better ensure the sustainable management of its water resources, safeguarding both the environment and the well-being of the communities that rely on these disaster prone areas.
Merapi volcano (2,930 m asl) ranks as one of the world's most active and densely inhabited volcanoes [10][11][12][13][14]. Every kind of water resource matters, particularly in Merapi' s disaster prone areas [18].In the Merapi area, which is known for its frequent volcanic eruptions, earthquakes, and associated hazards, the availability and management of water resources take on heightened importance for human survival, disaster preparedness, agriculture and livelihoods, community resilience and infrastructure protection [12,15].Existence of any water resources matters particularly in the context of disaster preparedness and rehabilitation.
Major and minor eruptions of Merapi volcano produce pyroclastic material spread to 10 rivers.Despite its status as the most active volcano in Indonesia, the surrounding communities have special bonds that encourage them to stay.Merapi eruption still occurs in 2023, when magma supplies triggered a shallow volcanic earthquake 8 km.This eruption caused a deformation of the volcanic edifice and produced Pyroclastic Density Currents (PDCs) 1-3 km from the summit.The pyroclastic materials are deposited at the upstream area of the rivers that originate Merapi volcano.This could be easily transported downstream by river flow [17].Although the volcano constantly causes high risk, local people still reside in the area because of ecosystem services that support their lives [18,19].
Identifying water utilization patterns within volcanic regions is indispensable for effective water resources management.In such dynamic environments, where geological processes and hydrological aspects are at play, understanding how water is used by local communities in these geologically sensitive areas allows us to pinpoint specific issues, such as water scarcity, groundwater contamination, or vulnerability to volcanic hazards [20].Armed with this knowledge, local governments acting as resource managers can develop targeted strategies and allocate resources effectively while ensuring the sustainable management of water resources in these unique and often vulnerable landscapes.
The concept of ecosystem services has demonstrated its important role by incorporating diverse expertise and stakeholder viewpoints into the issues of water resources management [21].Ecosystem services approach is important as it emphasizes the strong connection between ecological functions and socio-economic benefit.This approach can be utilized to improve the awareness in maintaining the human social needs in a sustainable way through the provision of ecosystem services [22].The results of the approach can be integrated into environmental policy and management decisions since they are assessed through the advantages they offer to people, fundamentally supported by the processes within ecosystems by articulating the connection clearly and need the interdisciplinary collaboration and stakeholder engagement at multiple scales [23,24].Application of ecosystem services approach is useful in determining priority issues particularly from the perspective of people as users.It is widely applied  [25], lake management [26] forest management [27], and land use management [28,29].
Previous studies related to water resources in Merapi volcano discuss river responses to eruption [30], adaptive water governance [31], governance of lahars [32] and water carrying capacity [33].Research of the application of Integrated Water Resource Management (IWRM) in Merapi by [34] has mentioned that IWRM should adapt to challenges of administrative boundaries.Rather than focusing in the top-down direction in IWRM, it needs another approach which considers the local needs and initiative within different administrative areas.The ecosystem services approach can fill this gap since it is more toward people as users (beneficiaries), local context and more pragmatic [21].The study of the river ecosystem services has not been well explored at Merapi volcano.The volcanic river is not only playing a role in providing water for people and the surrounding ecosystems but also receiving the volcanic materials injected during eruptions.The interrelation between volcanic activities and human activities will influence the river ecosystem services [30,33].Land use change, human population growth, agriculture, industrialization and urbanization are key factors of the functional and structural deprivation of rivers and streams on a global scale [35].Good governance and management strategies should consider this complexity [38].Based on this scientific background, it is important to define the river ecosystem services in Merapi volcano by exploring the water utilization.This study would be useful for improving the water resources management particularly in finding the issues priority based on river ecosystem services.

Research Method
This study examined the water utilization and river ecosystem services (RES) in the Krasak watershed southwest of Merapi volcano.The watershed has an area of 35.48 km 2 [33], spans two provinces (Central Java and Yogyakarta Special Region) as shown in Figure 1.Krasak watershed was affected by the Merapi eruptions in 2010 [37] and 2021-2023 [38].Krasak watershed received the third largest pyroclastic materials (10.8 million m 3 ) after Gendol watershed and Pabelan watershed during its major eruption in 2010 [39].It has two permanent rivers upstream, namely Krasak and Bebeng rivers in the east and west section, respectively.Furthermore, this area is affected by national infrastructure development plans such as Yogyakarta-Bawen highway [40].In terms of disaster risk, the watershed has been classified into three disaster-prone areas (KRB).
In this study, the evaluation of water utilization was carried out using the ecosystem approach from [41] and [42] with some modifications focusing on water utilization.Gaining the information of water utilization as a service demand is the initial stage of ecosystem services approach (ESA).To achieve this, we employed a case study approach as the primary research method.This method was chosen as it allowed the researcher to gain a comprehensive understanding of the research object [43].Semi structured interviews were conducted to households closest to the river (within a range of 100-500 m from the river) in six villages representing upstream, middle stream and downstream of Krasak river.These villages include four in Magelang Regency (Kemiren, Kaliurang, Salam, Bligo) and two in Sleman Regency (Lumbungrejo and Banyurejo).There were 42 informants interviewed, including inhabitants, head of hamlets and head of village.Purposive sampling was taken in selecting the informants with criteria including living in the village for at least 20 years and experiencing the eruption in 2010 and 2021-2023.We explored the types of water sources used, what activities are supported by these water resources and what kind of water problems encountered.The triangulation process was taken by doing observation and reviewing related institutional documents.Content analysis was performed to examine the water utilization and categorize the river ecosystem services, as perceived by local inhabitants into provisioning services, regulating services, supporting services and cultural services proposed by the Millennium Ecosystem Assessment [44].

Water utilization 3.1.1. Upstream.
There are three sources of water used in Kemiren and Kaliurang villages: springs, wells and rivers.Springs become the first choice of water due to their good water quality.Hence, it is used as the primary source for domestic needs including drinking water, cooking, shower and washing.For distributing the water to the households, a piping system is installed.In Kaliurang, people rely on springs managed by each hamlet.For example, the spring in Aren is distributed to Cempagan and Kaliurang Selatan hamlets.In Kemiren village, spring water (locally referred to as tok), is collected to one water storage facility and then distributed to 5-6 households.
The second water resource is well.For those who have enough money, they build wells for their household needs and small fish ponds.They can access water from wells with a depth of 5 meters.However, some wells have dried up, leading them to switch to spring managed by the village.There is also PAMSIMAS (Community-based Water Supply and Sanitation Program), initiated by the government (in this village by Dinas Pekerjaan Umum/Public Works Agency).It was constructed in 2021 but it has not operated yet.In Kaliurang village, a drilled well was built in the mosque area with a depth of 17 m.While in Kemiren village, people can access well water starting from a depth of 5 m.
PAMSIMAS is a rural water supply and sanitation development program implemented with a community-based approach.This national program was initiated by the Ministry of Public Works and Housing (Kementerian Pekerjaan Umum dan Perumahan Rakyat).It has been running since 2008 and continues to run until this year.This program has succeeded in increasing access to safe drinking water and proper sanitation for 25.9 million people in Indonesia [45].However, there are some problems emerging such as lack of water quality monitoring and communication between PAMSIMAS operators and water users, as occurred in one of the villages in Semarang [46].
The third water resource is river water.People use Bebeng River and Krasak River, located upstream of Krasak river, for irrigating rice fields, gardens, and small fish ponds.Since the water is murky, they prefer to use it for non-drinking water needs.In the past, people used river water for washing clothes and showering.River water serves as an alternative water supply, beginning with a simple filter process, in case the spring piping system is disrupted due to disasters or other technical problems.Moreover, in minimizing dust, people use river water to dampen the roads.There are some problems mentioned by the people in two villages as follow: 1.Low spring flow.Many springs have disappeared because of mining activities.2. Landslide can disrupt the piping system of the springs.3. Wells dried up and getting deeper.4. River course changes significantly.The water is murky especially in Bebeng River. 5.The supply water from springs and river is very limited.One of water tourism destinations in Kemiren stopped operating in 2018 since the spring and river could not supply enough water.
As informed by the informants, mining activities operate every day.It influences not only the rural transportation and road conditions but also polluting air.The presence of springs and wells is also disrupted.Tree planting in the upper reaches of Merapi has become futile.
"Next to the road over there, the springs have all disappeared into the ground because the river was dredged using tools" (Informant 1, Kemiren) "The wells no longer produce water because of the mining.If the mining is getting deeper, the water well is also getting deeper.People are unable to dig and are forced to use Bebeng water which is no longer suitable" (Informant 7, Kaliurang) As described on how they utilize the water, people were also asked about how they manage the wastewater and domestic garbage.They mentioned the following points: 1. Wastewater from the house is discharged into the pond (blumbang), septic tank and irrigation channel.2. Organic waste is thrown into the garden and buried; thrown into rice fields and garden for fertilizer.Plastic waste is usually burned.3.People use organic fertilizer as manure and compost for Salak garden and NPK fertilizer for other crops.Approximately 90% of the agriculture area is planted as Salak (snake fruit) garden.4.There is no waste disposal site built.Waste bank/bank sampah concept has been introduced and managed by youth even though the amount of the waste collected is still very small.5.There is a program for cleaning the irrigation channel and tree planting initiated by farmers groups.
Farmers in the upstream build rainwater harvesting pond.During dry season, they have to transport spring water from their settlement to their field in the above of the village to water their crops, such as chilies, corn and peanuts and other plants that require low watering.
"Forest farmer groups planted 1000 trees in the upper reaches of Merapi and people work together 'gotong royong' in cleaning the irrigation channel."(Informant 6, Kaliurang) "But now the spring flow is small due to mining activities that knock down trees and take sand.Planting trees has no function." (Informant 3, Kemiren) 3.1.2Midstream.Located in the middle stream of Krasak river, people in Salam village and Lumbungrejo village mainly rely on wells as their source of water supply.The well depths vary from 9 -17 m.They use it for various domestic needs such as drinking, cooking, showering, and washing.When there is a problem with the well, the water from PAMSIMAS and PDAM (Municipal Drinking Water Company) becomes the alternative.However, they use it for watering plants or cleaning, due to its lack of hygiene.
Krasak River serves multiple functions, including irrigation for rice fields, fish ponds/blumbang, alternative source for washing clothes in dry season and recreation.When people encounter problems with their wells and PAMSIMAS, they switch to river water that is distributed through a piping system.Before the 2010 eruption, the water was still clear but now it has become murky.In the past, the inhabitants did not use the river water directly for domestic purposes.Instead, they built a pond and used it only for bathing and washing.Furthermore, a tourist destination is also built close to the river, such as DAS Miring, located in Lumbungrejo.This place offers the opportunity to enjoy the river stream while engaging in activities such as gathering and sports.
There are several problems mentioned by the people in two villages: 1.During the long dry season, wells dry up and the PAMSIMAS system is also disrupted.2. Since there has been extensive mining activities following the eruption 2010, the wells have dried up more quickly.Previously, they found no issues with the wells.They could access the water from a depth of 7 meters, but now they have to dig deeper up to 9 meters.3. The river water is murky and polluted due to mining activities, sand washing and stone crushing.4. Open defecation in the river sometimes occurs which makes people hesitate to use water directly for bathing and washing activities, even in an emergency.
"During the dry season, there is little water in the well, so we ask for water from the neighbor's well."(Informant 8, Lumbungrejo) "When I was a child, the river water was very clear, but since the mining activities in the upstream, it has become murky."(Informant 10, Lumbungrejo) In addition to explaining how they utilize water, people were also asked about how they manage wastewater and domestic garbage.They mentioned the following points: 1. Latrine water is discharged into the river and septic tank.In Lumbungrejo, some people use a communal wastewater treatment plant provided by the government.2. Organic waste is either thrown into the garden and buried or used as fertilizer in rice fields.Plastic waste is usually burned.3.For farming, people use organic fertilizer as manure and compost and also chemical fertilizer such as NPK and urea.4. One waste disposal site is operated in Lumbungrejo.Meanwhile in Salam, a specific facility has not yet been provided.5. Waste banks/bank sampah operate differently in both villages.In Lumbungrejo, non-commercial waste is collected by Village-Owned Enterprises/BumDes before being managed by the Environmental Protection Agency of Sleman Regency (DLH Kabupaten Sleman).Commercial waste is collected by women of PKK (community organization that empowers women).In Salam, sorted garbage is collected by BumDes and commercial waste is managed by village youth who sell it to the junkyard.The involvement of youth, women, BumDes and local government agencies plays a prominent role in waste management.
3.1.3.Downstream.Located downstream of Krasak River, people in Bligo village and Banyurejo village primarily use wells as their source of water.It is practical for their domestic needs.In Bligo, the well depth starts from 4 meters, while in Banyurejo, the well depth starts at 10 meters.Thus, people in Bligo can access the water well more easily than those in Banyurejo.
Some residents use water from PDAM and PAM/PAMSIMAS systems to cover well water shortages when it recedes.For example, in 2020, people in Banyurejo switch from a well to self-support PAM system that is sourced from springs in Nglengis and Gedhangan.This change occurred because the river channel became deeper and the wells dried up.
For the irrigation of rice fields and fish ponds, people use several rivers.In Bligo, people use Krasak River, Petel River, Selokan Mataram (Mataram sewer) and Saluran Van der Wijck (Van der Wijck Sewer).Since it has high discharge, people prefer to use water from the Petel River.Krasak River becomes the alternative if there is a problem with the sewers or if the sewers have to stop due to maintenance issues.People in Bligo also utilize the Krasak River as a tourist spot when the flow is big enough.In 2019, river tubing was operated.Unfortunately it had to stop due to Covid-19 pandemic.Besides that, the discharge of the Krasak River is decreasing so the water tubing should be relocated to another river with a larger discharge.Meanwhile, people in Banyurejo rarely utilize water from the Krasak River; they rely on Saluran Van der Wijck, Selokan Mataram and other rivers such as Gremeng and Kerisan for irrigation.However, people utilize the beauty of the Krasak river by building a traditional market called "Lembah si Cangkring'' (Valley of the Cangkring)", located on the river bank IOP Publishing doi:10.1088/1755-1315/1313/1/0120047 of Krasak.Every weekend, this place is crowded with people from various regions, especially cyclists who pass the Banyurejo -Bligo route.The land used to be a paddy field and unused land with lots of wild plants.On January 1 2021, it was officially opened, managed by local residents in Jambeyan hamlet.The concept offered by this place is an old/jadoel market that sells a variety of traditional foods.
"For daily needs, we use a well, while for ponds and irrigation from the Mataram sewer (Selokan Mataram)."(Informant 13, Bligo) "We used to use a well, but as the river channel got deeper, the well dried up, so we changed to PAM Swadaya.Moved from the well to PAM around 2020.I pay 35.000/month for 2 houses."(Informant 14, Banyurejo) Despite both villages having many sources of water, there are still some problems mentioned by residents of the two villages: 1. Well water recedes particularly during the long dry season.2. The water supply of PDAM is limited, it cannot serve the whole household.3. Self-supporting PAM water is not sufficient, as the flow is unstable during both the dry and rainy seasons.4. Krasak River is difficult to access due to the deepening river channel.The river discharge is decreasing.
"When I was kid, the water level of the Krasak River was still the same as the surface level of the village, so the water was more abundant, there were many ponds in the village and there were many water reserves.But now that the water channel is getting deeper, it affects the depth of the wells."(Informant 16, Banyurejo) "Around the 1970s, it is said that there used to be a bridge in this area during flash floods (lahar), the last time it flooded was around that year, probably around 1972 or 1974.2010 was also affected by the eruption, the lahar flood reached this river (Krasak) but the water did not overflow out of the river."(Informant 17, Banyurejo) In addition to explaining how they utilize water, people were also asked about how they manage wastewater and domestic garbage.They mentioned the following points: 1. Latrine water is discharged into the river, septic tank, and garden.2. Organic waste is thrown into the garden and empty land, buried; thrown into rice fields for fertilizer.Plastic waste is usually burned.3.For farming, people use organic fertilizer as manure and compost as well as chemical fertilizers such as NPK and urea.4.There is no waste disposal site.However, in Banyurejo, regular garbage collection is available, which is not the case in Bligo. 5.The waste bank/bank sampah has been operating for months in Bligo, but it has stopped.In Banyurejo, the waste bank does not work as well.

River Ecosystem Services
As explained by informants, water sources in Krasak watershed vary from springs, wells and rivers.
Regarding the utilization of river water, there are several points of river ecosystem services that can be identified initially based on the informants' explanations.These points cover all components of river ecosystem services such as provisioning services, regulating services, supporting services and cultural services (Table 1).Information from local people is important since human end users are required when considering the value of ecosystem services.The first component mentioned by the informants in upper stream, middle stream and downstream is the provisioning service of Krasak River.Provisioning service encompasses products derived from the river [47].This service affects socio-economic development and vice versa [48].In this case, Bebeng River and Krasak River supply water for agricultural irrigation, especially for gardens and rice fields, as well as water supply for small fish ponds in Kemiren and Kaliurang Villages.This is the main benefit felt by the people living in the upper and middle reaches of the Bebeng and Krasak Rivers.Nevertheless, this service is less available to downstream communities as they have other river options that are more accessible and provide more water such as Kerisan, Gremeng and Petel Rivers.Furthermore, the river also provides people with an abundance of sand and stones because the river accommodates volcanic materials released by Merapi particularly in the upstream of Krasak.This service distinguishes rivers in Merapi volcano from other rivers.
The second river ecosystem service mentioned by informants is water quality as a regulating service.Regulating service encompasses those that regulate and maintain ecosystem processes, and facilitate ecosystem functioning and productivity [42].Mining activities, which were mentioned several times since their operation, cause changes in water clarity.After the eruption in 2010, people realized that river water became murky and cloudy.People start to associate the operational time of mining activities with the water quality.There was a time when the Bebeng River was polluted by solar fuel.Other informants also said that the color of the water turns milky white because there is a stone industry near the Krasak River.The infrastructure development such as the toll road in the downstream can also contribute to the water quality changes as well as other human activities around the river such as agriculture and farming practices, settlement areas and development of tourist spots.
Supporting service encompasses functions and processes that provide the foundation for the provisioning, regulatory and cultural services [47].They are essential for the production and maintenance of ecosystem structure and function [42].Supporting service of the river is identified through the statement of an informant about the algae bloom (red river) that happened in 2022 in Bebeng River (upstream).Although informants could not explain a lot about it, they felt that this phenomenon showed that there was something wrong with the river.The role of phytoplankton as producers in water bodies is a bio-indicator to determine the primary productivity.Algae blooms indicate an imbalance in the ecosystem and occur due to the high concentration of nutrients in the water, which can originate from domestic waste and fertilizers from agricultural activities [51,52].
Cultural services of the river reflect value derived from the existence of the river [47].Cultural service of Krasak River is identified based on informants' explanations.With the aim of utilizing the river water and enjoying the natural beauty of Merapi landscape, several tourism activities are organized by community groups in the upper, middle and lower reaches of the river.These activities include water tubing, outbound activities, and water sports.People also independently utilize the river for casual fishing and water play.Coffee shops, small restaurants and traditional markets are also built close to the river to attract people to come and enjoy the scenery.These activities are usually managed by community groups either in the form of Pokdarwis (Tourism Awareness Group) which already has a certain management structure at the village level or managed independently by certain hamlets.

Issues Related to Water Utilization and River Ecosystem Services
Based on explanations provided by informants, there is hesitation in utilization of river water.Changes in river channel, topography, lahar risk as well as human activities in the river such as increasing number of mining sites and people's habit in waste management influence the decision in utilizing river water.This will influence the way they value the river ecosystem services and finally become the challenge to environmental protection in general and river protection in particular [53].
Differences in the utilization of Krasak River water are influenced by the quality and quantity of water, ease of accessing water, and the presence of other alternative sources of water.This finding is consistent with the research conducted by [55] that revealed that distance to water sources as one of access factors to water besides affordability and the intended use of water.
The indication of water shortage in mid and downstream of Krasak can be related to water resources carrying capacity.Research conducted by [35] showed that increased population, followed by land use changes and increased evapotranspiration after eruption in 2021 affects shallow groundwater recharge at Yogyakarta Sleman Groundwater Basin.Water resources carrying capacity analysis show a decline, particularly in the midstream and downstream.
Mining activities mentioned by informants as a factor that changes the condition of Bebeng and Krasak Rivers, as well as the availability of springs and wells.Mining activities have a major role in changing the land use of Krasak watershed, especially Bebeng segment.Bebeng River serves 480 m 3 of volcanic sand per day [56].This characteristic defines it as a volcanic river that represents valuable resources injected by the eruption [30,34].Location of quarries also changes according to materials deposited by eruptions [50].However, over-excavation of sand in the rivers of Mount Merapi will degrade the riverbed and disrupt the sabodam [49].Mining activities bring up pros and cons due to the environmental and socio-economic issues [32], [49][50][51].This corresponds to [57] that points out groundwater depletion, damaged roads and river pollution as effects of mining activities that have been complained about by the residents.
The role of the local community that focuses on managing Krasak River also becomes another challenge, particularly in regular river monitoring.There is a lack of information about the water quality of the Krasak River.However, the existence of Village-Owned Enterprises/BumDes, Tourism Awareness Groups/Pokdarwis, tourism communities, farmer groups and Merapi volunteers at villages can be the locomotors in creating a community-based river management.This can be observed through initiatives such as waste management planning as part of the process of establishing a tourism village in Banyurejo, regular riverbank cleaning by the community running tourism spot (Lembah si Cangkring) and involvement of farmer groups in tree planting in Kaliurang.The involvement of the local community is essential for the integrated and sustainable river management [58,59,60].Furthermore, the efforts of the local community should also be supported by the government with clear regulation and assistance as ambiguity in roles, responsibilities, and poor accountability in water governance can lead to poor ecological conditions of rivers [36].

Conclusion
Water utilization in Krasak watershed comprises the use of springs and wells for supplying drinking needs and domestic needs as well as the use of rivers for irrigation water, fish ponds and recreation activities.Differences in the utilization of Krasak River water in upper stream, middle stream and downstream are influenced by the quality and quantity of water, ease of accessing water and the presence of other alternative sources of water.Due to water utilization, as explained by the local people, prominent services of the river can be identified as four components: provisioning services (irrigation water for agriculture, water for fish ponds, rural water supply, sand and stones), regulating services (maintaining water quality, and groundwater quantity), supporting services (primary productivity) and cultural services (recreation and aesthetic value).Challenges to the river ecosystem services include the hesitation in utilizing river water that will affect how people value the river and the role of local community and government in managing Krasak River.Furthermore, as this study revealed the preliminary river ecosystem services obtained from the perspective of local people, perspectives of other stakeholders are needed for future studies.In addition, studies on the assessment of river ecosystem services would be very useful to complement the findings of this study.
"A new PAMSIMAS was built in 2021 to help people at the east part of the village.The wells dried up there."(Informant 1, Kemiren)."Bebengriver water is collected in ponds, the water is murky.The water is used for fish ponds, as a water reserve if well and spring water stop flowing."(Informant 2, Kemiren).

Table 1 .
River ecosystem services of Krasak.