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Agriculture at nature's mercy

In recent decades, market forces have prompted farmers in the Sunderbans to choose modern, high-yielding varieties of paddy, oblivious to their sensitivity to salt. Cyclone Aila, which caused a huge inundation of salt in the fields, proved that this was a costly mistake: every farmer who sowed the modern seed ended up with no produce, while those who planted traditional salt-tolerant varieties managed to harvest a little rice. Sukanta Das Gupta reports

Cultivators in the remote islands of the Sunderbans have had more than their fair share of struggles against nature since the islands were cleared and made cultivable more than a century ago. They cleared the forest, made protective earthen embankments all around the islands to keep out the surrounding salt water, and waited through several monsoons so that surface salinity of the soil reduced. Soon agriculture became possible, and with agriculture a dense population sprang up on the islands.

The people of the Sunderbans maintained their determination to overcome nature’s unending challenges. It was a constant battle as the fragile embankments suffered continuous erosion, their upper surfaces from the onslaught of the waves and their foundations by powerful river currents. Indeed, the people here are accustomed to crumbling embankments, to cultivated plots being submerged, and to perpetual rebuilding.

On May 25, 2009, however, Cyclone Aila caused such widespread havoc that the brave islanders could do nothing but surrender to nature’s fury. The region was simply not equipped to deal with a calamity on this scale; nothing in living or recorded memory could have prepared them for Aila. The islands have weathered cyclones with greater wind velocity and some peripheral effects of the 2004 tsunami. But all this happened when water in the rivers was at a low ebb. In this inter-tidal zone, daily fluctuations in water level are at least 3-3.6 metres. On a full-moon or no-moon day, the amplitude increases to 5.4-6 metres. That fateful day, a no-moon day, Aila’s landfall coincided with the highest water level. The only reason the death toll (less than 100) was not greater is that Aila made landfall during the day.

Although the toll is tragic for the victims’ families, it is relatively low compared to the history of cyclones in the region. That’s why it masks the true impact, for it broke the backbone of agriculture on these islands. With experts predicting more frequent storms and cyclones as a result of climate change, Aila has shown us the vulnerability of coastal populations in the Sunderbans (both in India and in Bangladesh), a vulnerability that is shared by all coastal habitations in South Asia and threatens other such deltaic regions in the world.

Agriculture before Aila

There are 54 populated islands in the Indian Sunderbans, apart from 48 others that constitute reserve forests. On the inhabited islands, around 90% of households depend on agriculture directly or indirectly. Agriculture here is synonymous with paddy cultivation, in a region that is mono-crop due to the shortage of fresh water. On these islands, rain is the only source of water for agriculture because the groundwater in most places is salty. And it’s deep (as has been found by borewells on some islands), making lifting of water for irrigation economically unviable. So, the single crop that is raised is a product of the monsoon.

It was only natural therefore that the first settlers on the islands preferred rice which is salt-tolerant. Usually, soil salinity of 1-2 decisemens per metre (dsm) is ideal for raising crops. But if the salinity exceeds 3 dsm, it harms agriculture. The rice family comprises many varieties that have evolved through the ages in different soil conditions; there are some that can tolerate salinity above this margin.

Soil salinity in the Sunderbans during the initial years of settlement must have been quite high; we hear of rice varieties like Hamilton and Matla being grown here. These varieties were not known to exist outside the Sunderbans, suggesting that they were extremely salt-tolerant. As agriculture on the islands progressed, the salinity of the soil decreased and other varieties of rice began to be planted, like Dudheswar, Nona Bokhra, Nona Shal, andNona Kheetish. These were imported to the Sunderbans from the adjoining regions of southern West Bengal.

In recent decades, market forces have begun driving decisions, and productivity has become the yardstick by which farmers’ choices are determined. With a perverse sense of assurance against the possibility of salt water intrusion, farmers began choosing modern high-yielding varieties, oblivious to their sensitivity and vulnerability to salt. Under normal conditions, there were indeed demonstrations of significantly increased returns from the new varieties. This led farmers to ignore annual warnings of embankments being breached. And so, modern agriculture in the Sunderbans came to be dominated by rice varieties engineered for the mainland, with high productivity but little salt-tolerance.

Soil conditions after Aila

When the embankments crumbled under the force of Cyclone Aila, they could not be restored for over a month in many parts of the islands. This meant the flow of salt water into low-lying lands with the twice-daily turn of the tide. Every incoming tide contributed to fresh salt deposits on the exposed land. In other areas, where the destruction of embankments was not total, residents were able to carry out patchwork repairs more quickly to keep out the seawater. Cultivable land on the islands received varied levels of salt deposits on them, depending on the duration of their exposure to the surrounding rivers.

When, at last, the salt water receded, layers of salt still coated the upper surfaces. After Aila, land salinity in the Sunderbans, measured at various places on the islands, showed a range of 9-15 dsm! No expert on agriculture would recommend any variety of paddy for such land.

Farmers are experts in their field -- they waited and prayed for heavy showers to reduce the salinity. The cyclone hit shortly before the scheduled onset of the monsoon. The hope was that a long and heavy monsoon in 2009 would quickly wash away the salt. But the monsoon was late, irregular and deficient compared to the average.

Tanks and ponds

The Sunderban islands are dotted with tanks and ponds of various sizes. Almost every landed household has at least one tank. These tanks are the sole reservoirs of fresh water for domestic and agricultural work throughout the year. Not large enough to allow for another major crop during the dry season, the tanks help islanders store water required for ripening of the monsoon paddy in the last stage, well after the rains are over. They also help people grow vegetables like tomatoes and chillies, which do well in these parts. Further, the tanks hold freshwater fish stocks that provide the islanders essential protein. The monsoon is crucial therefore both for the paddy crop and for freshwater fish.

Towards the end of summer 2009, the tanks and ponds had only a minimum level of water, which is not unusual for this time of year.

When the cyclone struck, salt water surged into the tanks and ponds, destroying the freshwater fish. A day after the event, the islands were filled with the stench of rotting fish.

This also meant the end of tank and pond water to supplement agricultural needs after the monsoons.

The people of the Sunderbans and the administration understood the threat quickly. Together with rebuilding embankments, one of the early livelihood support programmes was to rid the ponds of saline water. Once the embankments were repaired, the Sunderbans Development Board (an apex state body to promote development in the area) gave the tank owners money to hire pump sets to lift the salt water out of their inundated ponds and make them ready to receive fresh monsoon water.

With NGOs aiding efforts, the recovery process in many islands appeared to be successful. Tanks and ponds were emptied to make way for rainwater from the months of August to October. Sadly, the result has not been what was hoped for. Although the ponds did receive fresh water directly from the rain, it had flowed across the land carrying with it salt that had accumulated on the land surface. After the monsoon, therefore, water that had collected in the tanks and ponds was saline -- unusable either for agriculture or for freshwater fish.

Even after the 2009 monsoon, soil salinity continued to be high. The state had to do something. The West Bengal Department of Agriculture tried to induce farmers in less saline pockets to attempt cultivation. It provided whatever salt-tolerant seed varieties were available in its reserve. Lunishree, Jarava, Sabita and Swarna seeds were distributed to a large number of farmers, many of whom, driven to desperation, were ready to take a chance with the adverse conditions. They had no other means to sustain their households and themselves. They built their seed beds on higher land where soil salinity was relatively low. They began late, well after the first monsoon showers. Some of the seeds failed to germinate; others that did were weak and died in the seed bed itself. Those that survived the initial phase were transplanted to the field when there was a reasonable level of standing rainwater.

After transplantation, the paddy did indeed grow, albeit not as vigorously as usual. The standing water had forced the salt to subside beneath the surface soil. At last the plants flowered and, in many places, showed initial signs of being an adequate crop. But then another problem cropped up. The monsoon began abating before the rice ripened, and the standing water in the fields evaporated. The salt from under the soil surface was sucked back up by the plants’ roots, crippling the plants and destroying the rice grain.

Mixed outcome

What was the outcome of the long, tiring struggle to return to normalcy in the Sunderbans? Almost every farmer who sowed the modern seed variety ended up with no produce. Those who were able to collect traditional salt-tolerant varieties, and were lucky to have lower salt deposits on their land, harvested a little rice. But their output was greatly reduced. Compared with the usual rice output in the Sunderbans -- 3.5-4 tonnes per hectare -- this harvest yielded only 1.5-2 tonnes per hectare.

The difference between local varieties and high-yielding varieties became glaringly clear. Local rice strains such as Dudheswar, Marichsal and Nona Bokhra performed the best, followed by HYV varieties like Lunishree, Jarava and Sabita. MTU7029, the most popular paddy variety in West Bengal, proved totally unsatisfactory in the area this year.

Apart from rice, the croplands produce some post-monsoon grain in normal years. One example is khesari, a pulse that requires little or no irrigation. Other commercial crops like sunflower, tomatoes and chillies are also cultivated in places where transportation is accessible and where ample water reserves (tanks and ponds) are available. Almost every household grows small quantities of winter vegetables, using pond and tank water, for their own consumption which is important for poor households. In 2009, however, after the monsoon, these crops failed entirely or had only marginal success.

The cycle of construction and destruction in the Sunderbans has gone on for years according to nature’s diktat. Historians agree that the islands have been depopulated and repopulated over and over again, and at all times the sustenance for people who chose to make the islands their home has been dictated by natural laws and events. This helps us understand that what is happening today is the rule, not the exception. And that the struggle for existence against all odds will continue. Compared with a generation ago, the effects of the 2009 cyclone were mitigated to the extent possible thanks to instant communications and the vast information network that was able to quickly mobilise aid and assistance. Yet the longer-term struggle continues, for after the failed crops of 2009 many of the islands’ men have temporarily migrated to find work. With climate change and the daunting prospect of further disruptions in weather patterns and cyclonic events, agriculture here will become increasingly fragile. As the latest experience shows, salt tolerance alone is not the solution; every aspect of the residents’ livelihoods must also change.

(Dr Sukanta Das Gupta is Assistant Director of Agriculture at the Department of Agriculture, West Bengal)

Infochange News & Features, July 2010