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: Wet winter may help Colorado River push off problems, but it will not end the drought

Related Stories

Chicago waterways—still flowing after over 100 years

March 7, 2017

As the city of Chicago has grown in population and industry since it was established more than 180 years ago, so has its need for clean water. Meeting that growing need has presented many challenges. Today, the Chicago Area ...

Opinion: What resilience should mean to policymakers

March 14, 2017

Evidence, and perhaps the experience of seemingly perpetual rain on one's face, suggests that the weather is one thing that is increasingly variable and difficult to predict. The impact of this goes beyond deciding whether ...

Desalination study authors explore fabricated membrane

November 1, 2015

Have scientists found a new way to purify sea water with materials that don't rely on electricity and are cheap enough to be manufactured in most countries? Might their work contribute to the search for a new, inexpensive ...

Recommended for you

El Nino and the end of the global warming hiatus

April 27, 2017

A new climate model developed by Yale scientists puts the "global warming hiatus" into a broader historical context and offers a new method for predicting global mean temperature.

Vinegar offers hope in Barrier Reef starfish battle

April 27, 2017

Coral-munching crown-of-thorns starfish can be safely killed by common household vinegar, scientists revealed Thursday in a discovery that offers hope for Australia's struggling Great Barrier Reef.

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.