Plants that take up salt could be used for biofuel and perhaps eventually reclaim lost land for crop production, scientists say
KARACHI, Pakistan (AlertNet) – Fatima Bibi, 36, looks back at the time when she was an affluent farmer.
“I along with my husband and two daughters used to grow rice, sunflower and vegetables. ... We would earn a hefty amount at the time of harvest,” she says.
But those days are gone. Bibi now earns her living selling biscuits from a stall at a bus stop in Badin, a town 200 km (125 miles) east of Karachi.
Her lifestyle was turned upside down when her 6 hectares (14 acres) of fertile land became saline, leading to a sharp decline in yield from her crops. With her income reduced, she and her husband Ali Raza set up their roadside stall to eke out a living for their family.
Vast tracts of arable land in Pakistan have been lost to waterlogging and salinity in the past few years, plunging into poverty millions of families like Bibi’s who depended on crop cultivation for their livelihood.
But scientists are holding out hope that the damaged land can be reclaimed by cultivating salt-tolerant plants for animal feed and to produce biofuel.
40 PERCENT OF FARMLAND SALINE
The Ministry of Food, Agriculture and Livestock says that in the past few years more than 6 million hectares (15 million acres) of cultivable land, representing 40 percent of the country’s total, has become saline and waterlogged. Experts say that this figure increases by 40,000 hectares (100,000 acres) every year.
Waterlogging and salinity of agricultural land is the biggest environmental issue facing Pakistan, and a huge threat to the sustainability of irrigated agriculture in the country, according to Charles A. Rodgers, a climate change specialist at the Asian Development Bank.
The problem has arisen gradually over the past century or more, say experts from the International Waterlogging and Salinity Research Institute, a government agency.
The water table of the Indus River plain, where most of Pakistan’s population lives, has been affected by irrigation systems, as water seeping from unlined channels and inadequate drains has percolated through the soil. The flat topography and poor natural drainage allow salt to build up in the soil as surface water evaporates during the dry season.
The process is “seriously harming agricultural output,” said Abdul Majeed Nizamani, president of the Sindh Growers Board, a farmers’ association in southern Pakistan.
But, in response, scientists have now identified several salt-tolerant species of plants, known as halophytes, which they hope can be used to reclaim saline and waterlogged soils.
RECLAMATION – AND BIOFUEL
M. Ajmal Khan, director of the Institute of Sustainable Halophyte Utilisation (ISHU) at the University of Karachi, said that salt-tolerant plants could be grown and then fermented to produce alcohol which could be used as a biofuel, reducing the need to burn fossil fuels that contribute to global warming.
The findings will be published in an upcoming issue of the Journal of Biomass and Bioenergy.
“These plants do not compete for good-quality water and productive farmland. They can be potentially used to produce large amounts of biomass when sown with brackish water on saline land, without competing with conventional agriculture,” Khan said. The plants grow rapidly year-round and are highly adaptive to saline soils, he said.
Halophytes offer further advantages, according to scientists. Irfan Aziz, an environmental scientist at ISHU, said they are more efficient than other plants in capturing carbon dioxide from the atmosphere.
In addition, it may prove possible to return to cultivating traditional food crops on previously saline and waterlogged land, once the salt-tolerant plants have been grown there for a few years, scientists say.
Scientists at ISHU have also identified salt-tolerant varieties of food crops, including wheat, rice, sugarcane, millet and maize. An awareness campaign is being planned to encourage farmers to try these crops on their saline land.
Meanwhile, efforts are underway to identify other salt-tolerant plant species for the production of medicines, edible oils, essential oils and turf for stabilising sand dunes.
But Arif Alauddin, chief executive officer of Pakistan’s Alternative Energy Development Board, a government agency, said that it will not be possible to reap the benefits offered by salt-tolerant biofuel plants without increased investment in research at the national level.
“We have some initial plans to promote salt-loving plants among grassroots-level farmers. But there will be a need for new investment by the private sector to promote cultivation of these plants,” Aluddin said.
Saleem Shaikh and Sughra Tunio are development reporters based in Karachi, Pakistan.
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