- Traditional oasis agriculture in Oman’s northern mountains is an outstanding example of sustainable land-use in dryland ecosystems.
- But major socioeconomic development throughout Oman over the past 50 years means that traditional agricultural practices, more than a millennium old, are changing too.
- Climate change is also affecting the types of crops that can be grown, particularly at higher altitudes.
- The high value of traditional agricultural products, agritourism, and new cash crops offer ideas on how to sustain the economic viability of these mountain oases.
In some ways, village life on Oman’s Jabal Akhdar Mountain is the same as it has always been. Water still runs through the ancient aflaj channels. People still cultivate pomegranates, walnuts and grapes. Goats still go out to pasture, and the day begins and ends with the call to prayer.
In other ways, life — and farming — is quite different. Over the past 50 years, Oman has developed at a dizzying speed, while climate change is also impacting agriculture. As change sweeps across these mountains, people are searching for ways to preserve and adapt these ancient oasis agroecological systems.
At first glance, Oman’s Hajar Mountains are an unlikely place for agriculture. This is a dramatic landscape of rugged plateaus slashed by deep, snaking canyons. It’s almost always sunny, and when it does rain, water rushes across the rocky hillslopes and cascades down the canyon walls in magnificent torrents.
But by channeling water from mountain springs and pools to terraced fields, and enriching the soils with manure from their goats, people have, for millennia, managed to grow an astonishing variety of food in a seemingly inhospitable land.
“It’s the only place in the world that I know of where 1,500 years of irrigated agriculture … has not led to salinization,” says Andreas Bürkert, professor in agroecosystems research at the University of Kassel in Germany. “In Oman, we can learn how [to do] agroforestry under irrigated dryland conditions with very little water.”
As the world grapples with unprecedented changes, Oman’s traditional knowledge of how to grow food sustainably in a dry climate may prove invaluable.
A sustainable agroecological system
Irrigated oasis agriculture is practiced all over the Hajar Mountains, but it is on Jabal Akhdar, a towering limestone massif in the center of the range, where some of the most spectacular examples are found.
This unique type of agriculture relies on three main components: the irrigation channels, rich terrace soils, and traditional knowledge.
The irrigation channels, known as aflaj (singular falaj), employ gravity to convey a steady stream of water from springs or other water sources to agricultural areas and villages. A communal resource, the water is divided into time shares according to customary rules. Traditionally, the aflaj channels were made from stone; today, many have been repaired with modern cement.
To create the terrace soils, farmers used a mix of clay, silt and gravel to get the proper drainage and minerals. For organic matter, they added large amounts of manure, primarily from their goats, which grazed freely on the surrounding mountain slopes.
Building up the soil took centuries, and tremendous effort. Bürkert and colleagues estimate that locals moved some 100,000 metric tons of sediments over the course of 600 to 800 years to create the gardens at the oasis village of Bilad Sayt, hauling it up from the riverbed basket by basket.
“It’s the admixture of the clay [and sediments] that comes from the river with the manure that was the secret of sustained fertility of the terraces,” says Bürkert, who has studied these systems for more than 25 years. “You see, in the soils when you pick them up, the upper 50 centimeters [20 inches] has a carbon content that is only comparable to compost.”
Finally, there are traditional farming practices, including planting a diversity of crops in agroforestry systems. The wide variety of crops across the mountains reflects Oman’s trading connections with Asia, Africa and the Mediterranean, while the types of crop depend on the elevation. For example, in villages lower down the mountain, at 1,000 meters (3,300 feet), locals plant date palms alongside banana, papaya and guava, as well as tomatoes, wheat and other annual crops underneath. Closer to the top of the mountain, at elevations of about 2,000 m (6,600 ft) where it’s cooler, they grow pomegranates, apricots, plums, walnuts and others, as well as wheat, alfalfa, carrots and other vegetables.
Over time, many of the varieties evolved and adapted to the local conditions. Overall, researchers have found 10 new wheat varieties in Omani mountain oases.
These traditional agrecological practices, including frequent rotations and fallow periods, also lead to impressive yields. For example, alfalfa (Medicago sativa) is harvested up to 12 times a year at 2 metric tons each, Bürkert says; per area, this is a higher yield than is achieved in California today, he adds.
The relative isolation of the gardens, surrounded by the harsh, arid environment, also meant that pests didn’t usually take hold. When outbreaks did hit, people used natural remedies derived from juniper and other wild plants, says Rashid al-Yahyai, professor of horticultural sciences at Sultan Qaboos University in Muscat.
This reliance on natural pest control methods is still evident in the healthy diversity of weeds, says Annette Patzelt, senior lecturer at Weihenstephan-Triesdorf University of Applied Sciences in Germany. Patzelt, a botanist, has documented more than 200 weed species in the terrace gardens, as well as a diversity of wild plants, including the endemic Omani bluebell (Campanula akhdarensis), which grows in crevices in the stone terrace walls.
Change comes to the mountains
While these agricultural systems have sustained people for millennia, they may be facing their biggest challenges today.
The first thing that’s changing is the climate, just as it is all over the world. Rainfall across Jabal Akhdar declined by an average of 9.4 millimeters (0.37 in) per decade from 1979-2012, which means there’s less water to recharge underground aquifers. At the same time, it’s getting hotter. Crucially, there are fewer cold nights, what are known as “winter chill hours,” which some temperate trees need to bear fruit.
From 1991-2018, oases gardens on Jabal Akhdar lost between 18% and 75% of winter chill hours, according to a 2020 study by Bürkert, with the greatest declines at higher elevations. In an earlier study on the same topic, Bürkert and colleagues noted that in some places the conditions for traditional trees like walnut, apricot and peach had already become marginal and “might become impossible in the near future.”
The second major change is socioeconomic, and reflects wider development across Oman. In 1970, when Qaboos bin Said took the throne as sultan of Oman, GDP per capita was just $382 USD, and there were just a few kilometers of paved roads. Over the next half-century, Qaboos would go on to radically transform Oman, initially using revenue from oil and later diversifying the economy into tourism and other sectors. That legacy has been continued by the current sultan, Haitham bin Tariq, Qaboos’s cousin, who succeeded him upon Qaboos’s death in 2020. In 2022, Oman’s GDP per capita was more than $25,000 USD, and roads now reach virtually all villages.
In the mountains, these economic changes have led to a shift away from subsistence agriculture. People are moving out of mountain villages for jobs or higher education, leaving behind the older generation to take care of the land, or returning to farm only on the weekends. Migrant laborers, mainly from Bangladesh and Pakistan, are taking on more of the daily farm chores.
Unsurprisingly, better roads and tourism development are also having an impact. In the past, access to the Jabal Akhdar plateau was limited by poor access. But in 2006, the government built a new three-lane tarmac road to the top of the plateau, opening up the area to tourists. Luxury hotels and holiday homes started going up, putting additional pressure on groundwater systems.
To document these changes, Bürkert and his colleagues surveyed villages in Wadi Muaydin soon after the new road opened and again a decade later. The findings, published in a 2021 Scientific Reports paper and a 2022 PLOS ONE paper, documented changing agricultural practices. Villagers were planting more cash crops, bringing in more animal feed, and using more agrochemicals, though manure was still widely applied. Locals left more land fallow and abandoned some terraced plots altogether. The villagers told the researchers that a “shortage of irrigation water and deep societal change” were the main challenges.
Way forward
Twenty-nine-year-old Mohammed al-Sheriqi grew up in the 500-year-old hamlet of As Suwgra, a jumble of stone and clay houses tucked against a rock face on Jabal Akhdar. He recalls how, when he was a child, farmers had to load up donkeys and make a three-day round-trip journey to the nearest market to sell their extra produce.
Life changed in 2004 when a gravel road was built to the area, connecting As Suwgra with other villages. Unable to traverse the deep wadi, or riverbed, with its falaj and gardens, the road stopped 500 m (less than half a mile) short of the village, on the opposite bank of the wadi. Within a decade, the village shifted to the edge of the road, where people built new, modern homes and could take advantage of easier access to electricity and other services.
But al-Sheriqi, and other locals, didn’t want to see their old homes just crumble to dust. So, inspired by an ecotourism venture elsewhere in the mountains, they began repairing the old stone houses. They opened the traditional-style guesthouse with just two rooms in 2016. Now they have 11 rooms, and the guesthouse employs 20 people from the village.
“It’s not just an accommodation,” says al-Sheriqi, who is now the manager. “It’s built for the Omani old experience, to show the tourists how we live and the heritage of the Omani people.”
There’s also growing interest in agritourism. Numerous tour operators offer rosewater and pomegranate tours, which Athul Vijayan of Zahara Tours says tourists like because they don’t expect to see agriculture in Oman, so it captures their imaginations.
Ecotourism ventures are one way to create economic opportunities for locals. Another is tapping into the high value of locally grown products.
“The perception is that the [Jabal Akhdar products] are organically grown, they are natural, they have higher nutritional value and are a traditional crop,” says al-Yahyai, the horticulture professor. “People go for these kinds of crops and they pay more for it.”
For example, pomegranates from Jabal Akhdar sell for 1 rial ($2.60) or more per fruit, al-Yahyai says, more than twice the cost of imported ones. Often, as with dates, the entire tree’s produce will be presold through an auction prior to harvest. Other local products, such as rosewater and local goat meat, also command high prices.
While largely positive, al-Yahyai points out that agricultural production is constrained by the availability of land and water. Aside from pomegranates, most of what’s grown in terrace agriculture is for home consumption. The high value of fruits like pomegranates can also be a double-edged sword when it comes to food diversity, Al-Yahyai says, if farmers choose cash crops at the expense of other local fruit varieties, which “are very important for everything from pest resistance to adaptation to climate change.”
Locals are also exploring new crops. Since 2014, the Omani government has successfully promoted the cultivation of imported olive varieties, building two olive oil processing facilities.
So far, the reception has been enthusiastic, al-Yahyai says. People like to grow olives because the tree is frequently mentioned in the Quran, and the trees produce good yields. In 2022, Jabal Akhdar produced more than 10,000 liters (2,600 gallons) of olive oil, valued at 200,000 rial ($520,000 USD). Al-Yahyai says farmers can sell the oil for about 20 rial ($52 USD) per liter (about $200 per gallon) — more than four times the price of imported olive oil. So far, the olive trees are complementing rather than replacing other crops, because they’re planted in home gardens instead of the terraces and use drip irrigation.
In 2022, the luxury hotel in Jabal Akhdar held its first olive festival, giving guests the chance to harvest the fruit from the hotel’s 170 trees.
While these various developments generate income for farmers and locals, other essential challenges will need to be addressed for the longer-term sustainability of these agricultural systems.
Water availability remains a critical issue, and is likely to intensify as both climate change and urban development intensify. In 2019, the government began experimenting with the use of treated graywater — wastewater from sinks and showers — for irrigation in Wadi Muaydin. Many villages on Jabal Akhdar now also use desalinated water for domestic use, delivered via a pipeline from the coast.
A more intransigent problem, says Bürkert, is the erosion of traditional knowledge, particularly as people move away from the villages and more of the daily labor is taken on by migrant workers who don’t have the same intimate knowledge of how to farm in these mountains. Without the traditional knowledge of how to maintain soil fertility, and the close integration between raising goats and cultivating crops, the system may not survive.
Still, there are positive signs. Anecdotally, use of synthetic pesticide remains rare. Manure is still liberally applied, and the diversity of crops remains high compared to many other places in the world, according to Bürkert’s 2022 study. Perhaps most importantly, these agricultural systems, and their produce, are still highly valued.
“Although you may say the area is much too small to feed the country, it’s social-ecological land use is … a model for sustainability, as it is based on what we are longing for, the integration of animal husbandry and plant cultivation,” Bürkert says.
Banner image: The olive harvest festival at the luxury Anantara Al Jabal Al Akhdar Resort in 2023 highlights the growing interest in local foods and agri-tourism opportunities. Over the past ten years the Omani government has been promoting the cultivation of domesticated olive trees on Jabal Akhdar; in 2023, the region produced over 10,000 liters (2,600 gallons) of olive oil valued at 200,000 rial ($520,000). Image by Anantara Al Jabal Al Akhdar Resort.
Citations:
Gebauer, J., Luedeling, E., Hammer, K., & Bürkert, A. (2009). Agro-horticultural biodiversity in mountain oases of northern Oman. Acta Horticulturae, (817), 325-332. doi:10.17660/ActaHortic.2009.817.34
Al-Maskri, A., Nagieb, M., Hammer, K., Filatenko, A. A., Khan, I., & Bürkert, A. (2003). A note about Triticum in Oman. Genetic Resources and Crop Evolution, 50, 83-87. doi:10.1023/A:1022986113736
Al-Kalbani, M. S., John, C., & Martin, F. P. (2015). Recent trends in temperature and precipitation in Al Jabal Al Akhdar, Sultanate of Oman, and the implications for future climate change. Journal of Earth Science & Climatic Change, 06(08). doi:10.4172/2157-7617.1000295
Bürkert, A., Fernandez, E., Tietjen, B., & Luedeling, E. (2020). Revisiting climate change effects on winter chill in mountain oases of northern Oman. Climatic Change, 162(3), 1399-1417. doi:10.1007/s10584-020-02862-8
Luedeling, E., Gebauer, J., & Bürkert, A. (2009). Climate change effects on winter chill for tree crops with chilling requirements on the Arabian Peninsula. Climatic Change, 96(1-2), 219-237. doi:10.1007/s10584-009-9581-7
Bürkert, A., Dix, B. A., Al Rawahi, M. N., & Schlecht, E. (2021). Agro-ecological landuse transformation in oasis systems of Al Jabal Al Akhdar, northern Oman. Scientific Reports, 11(1). doi:10.1038/s41598-021-85515-9
Schlecht, E., Dickhöfer, U., Aloufi, S., Alqaisi, O., & Bürkert, A. (2022). Showcasing the multifaceted aspects of agricultural transformation: The example of mountain oases in Oman. PLOS ONE, 17(11), e0276580. doi:10.1371/journal.pone.0276580
Bürkert, A., Luedeling, E., Dickhöfer, U., Lohrer, K., Mershen, B., Schaeper, W., … Schlecht, E. (2010). Prospects of mountain ecotourism in Oman: The example of As Sawjarah on Al Jabal Al Akhdar. Journal of Ecotourism, 9(2), 104-116. doi:10.1080/14724040902803404