Majuli: For centuries, Mising farmers of Assam have cultivated Bau Dhan, a flood-tolerant paddy variety adapted to the rhythms of the Brahmaputra. But changing rainfall patterns now threaten its survival. “In Assam’s floodplains when the river rises, so does the rice.”
Majuli, the world’s largest river island and the cultural heart of Assam, lies cradled between the mighty Brahmaputra and its tributaries. This floodplain ecosystem is home to the Mising tribe, whose agricultural calendar has long been synchronized with the river’s rise and fall.
Bau Dhan, a deepwater paddy variety, thrives here in monsoon-swollen fields, growing in step with the rising waters.
Majuli’s fertile silt soils, abundant biodiversity, and traditional ecological knowledge have sustained this unique farming system for generations. However, erratic weather patterns in recent years have begun to disrupt these age-old cycles, placing both the crop and the culture it sustains in jeopardy.
A Living Agro-Ecological System
Bau Dhan—a “floating rice,” “deepwater paddy,” or “flood tolerant” variety—is cultivated in flood-prone lowlands of Assam, particularly in the Brahmaputra and Dhansiri river basins.
Varieties under Bau Dhan include Negheri Bau, Bam Kokuwa Bau, Doh Kokuwa Bau, Maguri Bau, Kola Amona Bau, Boga Amona Bau, Rangali Bau, Moimonsingia Bau, Bogi Jul, Hindi Bau, Jul Bau, and Adolia Bau. Known for its remarkable ability to elongate its stems in response to rising floodwaters, Bau Dhan is perfectly adapted to an ecosystem where inundation can last for months.
Historically, the Mising community and other riverine farming groups have cultivated Bau Dhan not just as a staple crop, but as an integral part of their agroecological system. Sowing begins in early summer when the fields are still moist from pre-monsoon showers.
As monsoon rains arrive and rivers swell, Bau seedlings stretch upward, sometimes exceeding heights of 8 feet, keeping their grain heads above water.
This variety is purely rainfed and requires no chemical inputs, relying instead on the fertile silt deposited by annual floods. Its cultivation is deeply intertwined with traditional knowledge systems—seed selection, field preparation, and harvest rituals like “Haaria” (collective work)—passed down generations and often involving community labour-sharing practices.
Beyond its role as a food crop, Bau Dhan supports a complex web of biodiversity. Its flooded fields provide breeding grounds for fish, shelter for aquatic plants such as Zizaniopsis miliacea, Elytrigia repens, Hymenachne amplexicaulis, Greater Duckweed, Water Spinach, and Alligator Weed, and foraging spaces for migratory birds.
Livestock graze on post-harvest stubble, completing a closed-loop, integrated farming system.
Once harvested in late autumn, Bau Dhan yields highly nutritious grains with a distinct flavour, forming the basis for many cultural delicacies during Mising festivals. In essence, Bau Dhan is more than a crop—it is a living heritage, a climate-smart practice rooted in harmony between people, water, and land.
Current Challenges and Threats
In recent years, the cultivation of Bau Dhan has faced mounting pressures. Field observations in Majuli during the current agricultural season reveal a worrying shift in weather patterns.
Traditionally, the island experiences steady monsoon rains and periodic flooding from late June to September—conditions essential for Bau Dhan growth. However, in 2025, the region saw an extended dry spell lasting nearly 30 days during what should have been peak monsoon.
This prolonged drought has severely affected soil moisture levels. Without sustained waterlogging, Bau Dhan plants are unable to elongate as required, resulting in stunted growth. “There are heavy weeds growing and its outbreak—just because there is no waterlogging,” said Nandey Narah (38), a Bau paddy farmer.
Farmers report that this year, water levels in fields never reached the depth needed for optimal stem elongation, and in many areas, seedlings have wilted.
Moreover, the absence of usual moderate to high floods has disrupted the ecological balance of the paddy fields—fish breeding has declined, aquatic weeds that normally provide fodder have not grown, and migratory birds that depend on these wetlands are fewer in number.
The impacts are not only ecological but also socio-economic. Many Mising families depend heavily on Bau Dhan as both a staple and a source of income.
Poor yields threaten household food security and force families to buy rice from markets, increasing dependency on hybrid varieties and commercial inputs.
Traditional seed preservation practices are also at risk. When harvests are low, farmers prioritize immediate consumption over saving seeds for the next season, leading to gradual erosion of the genetic diversity of Bau Dhan strains. “Its limit for indigenous crop conservation threatens the continuity of the practice,” experts warn.
Field discussions with elders in Majuli reveal deep concern. While they acknowledge that occasional years of poor floods have happened historically, the current pattern of erratic rainfall and near-absence of floods in multiple consecutive years is unprecedented in living memory.
“The traditional ecological cycle that has sustained Bau Dhan cultivation for centuries is being disrupted, leaving farmers with fewer options and increasing vulnerability to climate shocks,” said Kerumoni Payeng (51), a Bau paddy farmer.
If such trends continue, not only will yields decline sharply, but the entire ecosystem—comprising aquatic life, soil fertility, and associated biodiversity—will degrade. The loss of Bau Dhan would mean the collapse of a unique agroecological system that sustains both people and nature in Majuli.
A Changing Climate, A Struggling Crop
Climate change is manifesting in Majuli through unpredictable rainfall, reduced flooding, and prolonged droughts. Bau Dhan, which evolved in sync with seasonal flood cycles, is highly sensitive to these changes.
The crop depends on gradual, sustained flooding to trigger stem elongation and maintain high soil moisture until maturity. “This year’s deficient rainfall and absence of significant floods, and even the closing of many small water streams by embankments, have disrupted this growth pattern, directly impacting yields,” said Momee Pegu, a social worker in Majuli.
Moreover, the ecological services provided by Bau Dhan fields—such as fish breeding, nutrient cycling, and bird habitats—are diminishing as water levels drop.
Without these seasonal wetlands, aquatic biodiversity suffers, and the natural fertility cycle is broken, increasing pressure to use external inputs like fertilizers during “Bodo Kheti”—a paddy cultivation practice during the rabi season.
For the human community, this translates into reduced food sovereignty, increased reliance on market-purchased grains, and loss of cultural food traditions. Climate change thus threatens not only an agricultural practice but an entire knowledge system that integrates farming, ecology, and cultural identity.
Future of Bau Dhan Practices and Its Culture
The future of Bau Dhan depends on urgent conservation efforts that combine traditional knowledge with adaptive strategies for a changing climate. Community-led seed banks like “Kumsung,” improved community institutional management, and research into resilient deepwater varieties could help safeguard the practice. Documenting and passing on the cultural and ecological knowledge of Bau Dhan cultivation to younger generations is equally crucial.
If no intervention is made, erratic rainfall and reduced flooding may render Bau Dhan cultivation unviable within a few decades, erasing a centuries-old agroecological heritage. This would not only mean the loss of a unique crop but also the collapse of an entire ecosystem and the cultural identity it sustains. By recognizing Bau Dhan as both an ecological asset and a cultural treasure, Assam can chart a path toward climate-resilient farming that honours its riverine traditions and promotes natural farming.
Why It Matters
Bau Dhan is a rare example of how agriculture can adapt to, rather than resist, natural extremes. It demonstrates that floods—often seen solely as disasters—can be harnessed for food security, biodiversity conservation, and cultural preservation.
Yet, as climate change disrupts the timing and intensity of floods, the delicate balance that sustains Bau Dhan is breaking. Without interventions to secure water availability during critical growth stages, Assam risks losing not only a rice variety but a centuries-old model of ecological resilience.
Views expressed are personal. The author is a farmer based in Assam.
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