Linda Yulisman, Jakarta – In the heart of Bali, where yellow-green paddy terraces ripple across the landscape like waves, ancient subak rice fields stand as witness to the island's rich cultural heritage. These intricate, community-led irrigation systems have nourished both the land and its people, a symbol of the delicate balance between nature and tradition.
But as the shadow of climate change looms larger with each passing year, this harmonious relationship is under threat. Experts warn that by 2050, the picturesque subak rice fields could face extinction, leaving the island's landscape and way of life irrevocably altered. But such a scenario can be avoided with countermeasures, they add.
Indonesia's subak system in Bali tops the list of 50 Unesco World Heritage sites at risk of extinction by 2050 due to climate change, according to a study by Climate X. Bali's subak is vulnerable to surface flooding, extreme heat and drought, noted the study that was released in August.
"Our findings serve as a stark warning for governments, preservationists and the global community to prioritise the safeguarding of our planet – to preserve our ancient monuments and our current assets and infrastructure – and to protect life today and into the future," Climate X's CEO and co-founder Lukky Ahmed said.
Subak is a thousand-year-old system that ensures fair water distribution to all farmers within a specific community. The water, sourced from lakes, rivers or springs, is channelled through canals, weirs, villages and temples, wending its way downhill to irrigate subak land.
The climate risk analytics firm looked at 500 sites and identified the 50 most at risk due to climate change. Other Indonesian World Heritage sites facing extinction risks by 2050 include the Ombilin coal mine in West Sumatra and Komodo National Park – home to the world's largest living lizards – in East Nusa Tenggara.
Agricultural technology expert from Yogyakarta-based Gadjah Mada University, Dr Hanggar Ganara Mawandha, whose area of research is subak, said that irregular weather patterns such as prolonged dry seasons or unexpected heavy rainfall have affected the water sources that feed the subak system, resulting in poor harvests for farmers.
"The management of subak is by consensus (as each subak community ensures the even distribution of water to farmers). It's very vulnerable to climate change. When water from the resources decline, it's hard to distribute the water (fairly)," he told ST.
Farming has become more challenging over the past two decades, particularly due to a recurrent decline of water flow quantity in his (subak) irrigation system, said Mr Wayan Subawayasa, a farmer in the village of Jatiluwih, situated on the slope of Mount Batukaru in central Bali.
The 32-year-old father of one used to grow paddy in a 0.79ha plot of land, but now can only make use of 0.6ha due to the reduced water supply. He plants fruits in the rest of the plot.
"I shifted to organic farming because the water is not sufficient for conventional farming. Residue from chemical fertilisers also causes land to dry up, absorbing a lot of water," Mr Wayan told ST, adding that he has had to source for paddy varieties with a shorter life cycle to keep his subak yields steady at 2.5 tonnes per harvest.
Some of his fellow farmers in surrounding villages have turned to rain-reliant farming, or replaced paddy with other crops, he added.
Dr Alit Artha Wiguna, a senior agriculture instructor at Bali's Agricultural Equipment Standardisation Agency, acknowledged that extreme situations associated with climate change have considerably lowered the productivity of Bali's subak farmland.
"In the past, paddy production reached 8 to 9 tonnes per hectare in Bali per harvest (for subak), but now it's only 5 to 6 tonnes per hectare," he told ST.
In addition to the vagaries of weather, subak faces competition from the tourism sector, which consumes vast amounts of water. Tourism, which is the main source of income in Bali, takes up 65 per cent of the island's water, according to Bali-based green group IDEP Foundation.
Shrinking subak land area can also be attributed to the conversion of the land for non-farmland purposes like building hotels and resorts, or infrastructure such as toll roads, experts and green groups say.
Nearly 20,000 hectares of subak land in Bali – about one-third the size of Singapore's land area – are recognised as a Unesco World Heritage site, although the actual area is much higher. A 2021 academic paper published by International Journal of the Commons estimates about 800 subaks managing around 86,000ha of paddy fields in 2010, with a loss of 1,000ha to 2,000ha a year since then.
One way to counter the shrinkage of subak land is through the development of ecotourism, a form of tourism that is responsible for the preservation of nature and makes a positive contribution to the welfare of local communities, which is expected to reduce the conversion of rice fields, experts say.
They say that other ways to preserve subak as a cultural heritage would be for more government support such as tax exemptions for subak areas, providing insurance assistance in the event of crop failure, aid for irrigation maintenance and repairs, incentives for subak managers, and scholarships for the children of subak farmers.
"Farmers really need the exemption of land tax and other subsidies that directly affect their production, especially subsidies on fertilisers and seeds," said Dr Alit from the agricultural agency.
Executive director of Bali's chapter of the Indonesian Forum for the Environment (Walhi), Mr Made Krisna Dinata, pointed out that the presence of subak helps to mitigate disasters, particularly flooding.
"Regions where the number of subak has declined are prone to flooding," he said, citing major floods in 2019 that affected Jembrana in west Bali region, where some subak plots had earlier been lost to land conversion. More subak land is at risk from plans to build a 97km connecting toll road that would affect 98 subaks covering about 480ha, he added.
Concerted efforts by the local community in tandem with universities, government agencies and non-governmental organisations will help subak survive and thrive.
One initiative that is being tried out is an intermittent irrigation method, which distributes water only when rice fields are in need. Dr Alit said this increases the land's productivity by 20 per cent.
Another initiative, introduced by a team of experts from University of Muhammadiyah Malang, is to maintain rainwater catchment areas on the upper part of the river and planting water hyacinth to filter pollutants.
"(Raising) awareness AMONG the local community on managing their subak will also prevent subak from going extinct," said Mr Galit Gatut Prakosa, who leads a team from the University of Muhammadiyah Malang to assist the Bali farmers in adopting a ecohydrological approach to subak management.
Dr Hanggar said that the survival of subak depends on how well the Balinese adapt to the challenges thrown up by climate change in the coming years.
"By engineering, we can introduce intervention measures to cope with the changes in rainfall patterns or duration of the dry season. If subak farmers are willing to accept them, such as changing their planting methods, they are able to adapt," he said. "But it's not easy to change the current mindset," he said, in addition to other factors such as cost and lack of knowledge.