Pickleweed tolerates irrigation with seawater and high levels of boron

October 8, 2008

Reuse of agricultural drainage water (DW) for irrigation is one of the few on-farm water management options available to growers on the west side of California's San Joaquin Valley (SJV) for reducing drainage water volumes (San Joaquin Valley Drainage Implementation Program, 2000). Management strategies that reduce drainage volumes are attractive because they would reduce the area required for environmentally sensitive evaporation ponds and lower the costs associated with disposal of the final effluent. Moreover, reductions in drainage volume would reduce the amount of trace elements (Se, B and Mo) and nutrients reaching the San Joaquin River and would help grower's meet newly established targets for total maximum daily loads (TMDLs).

In sequential reuse systems, saline drainage water is sequentially applied on progressively more salt-tolerant crops where application of concentrated effluents to halophytes is the final step in the sequence prior to disposal or treatment. However the effectiveness of halophytes in reducing drainage volume is dependent upon their ability to tolerate extremely high levels of salinity and boron over the long term, maintain high rates of evapotranspiration, and thrive in saline-sodic conditions with poor physical conditions.

Grattan et al. conducted greenhouse experiments with Pickleweed, Salicornia bigelovii Torr., a halophyte native to North American coasts and arguably one of the most salt-tolerant vascular plants. It has also sold in European markets as green tips used in salads and cooking and its seeds produce oil that is high in polyunsaturated fat.

The authors found that S. bigelovii grow very well over a range of salinity treatments (19-52 dS/m) comprised of either seawater or hyper-saline drainage water. Moreover, the plants were also able to tolerate high concentrations of boron (28 mg/L), an important constituent found in drainage water. The most remarkable find for Grattan and co-investigators was that evapotranspiration (ET) rates from these plants exceeded that lost from an evaporation pan by 1.5 to 2.5 times. Grattan and co-workers also developed a method to separate evaporation and transpiration by accounting for the changes in the isotopic signature of water in the reservoir due to evaporation. They found that high ET rates were due primarily to high transpiration rates (> 78% of ET).

"This finding is somewhat surprising considering this halophyte has no true leaves," commented Grattan. Although some challenges remain regarding the consistent establishment of S. bigelovii under field conditions, these data indicate that hypersaline drainage water, characteristic of California's Westside of the San Joaquin Valley, can be used to irrigate this halophyte and substantially reduce drainage volumes.

Source: Soil Science Society of America

Explore further: Fertigation strategies improve production of Hippeastrum

Related Stories

Fertigation strategies improve production of Hippeastrum

August 30, 2016

Recent studies have demonstrated that a priority for the floriculture industry is identifying environmentally friendly production strategies that result in marketable ornamental plants. The authors of a report in the June ...

Saving water with superabsorbent polymers

August 26, 2016

Soil conditioners called superabsorbent polymers have the potential to reduce irrigation needs for agricultural crops by storing water and nutrients and then releasing them in drought conditions, according to a recent paper ...

Upstream trenches, downstream nitrogen

July 13, 2016

Water quality scientist Laura Christianson is working on a solution to the "dead zone"—an area with dangerously low levels of oxygen— in the Gulf of Mexico. Christianson lives over a thousand miles north of the Gulf in ...

Flood forecasting gets major upgrade

August 25, 2016

The recent floods in Louisiana have reminded the nation of the devastation these disasters can cause, resulting in more than a dozen deaths and damaging more than 40,000 homes. David Maidment, a civil engineering researcher ...

Recommended for you

Melting Greenland ice threatens to expose Cold War waste

September 26, 2016

A snow-covered former US army base in Greenland—dubbed "a city under ice"—could leak pollutants into the environment as the climate changes, raising difficult questions over who is responsible for a clean-up.

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

Yogaman
not rated yet Oct 08, 2008
What happens to the salt and boron (and selenium, etc.) over time? Do they accumulate in the soil or get transferred to the harvest? For extra credit, please name some other unintended consequences.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.