Green is good — right? Not necessarily when it comes to lawns, according to a new study by UCI researchers. For the first time, scientists compared the amount of greenhouse gases stored by ornamental turfgrass to the amount emitted in the irrigation, fertilizing and mowing of the same plots.

In four parks near Irvine, they calculated that emissions were similar to or greater than the amount of carbon dioxide stored through photosynthesis — a finding relevant to policymakers seeking to control the gases that trap heat in the atmosphere and contribute to climate change. “Green spaces may be good to have,” said geochemist AmyTownsend-Small, the lead researcher in the paper published in the journal Geophysical Research Letters. “But they shouldn’t be automatically counted as sequestering carbon.”

The paper is particularly timely, she added, because governments are calculating their carbon footprints, and discussing whether parkland could offset other sources of emissions, such as refineries, power plants and automobiles. Turfgrass covers about 1.9% of the U.S. and is the most commonly irrigated crop. It is increasingly in demand in urban areas.

Townsend-Small and colleague Claudia Czimczik measured the carbon stored in the parks’ soil samples, and compared that with emissions from producing fertilizer, from mowing with gasoline-powered equipment and from pumping water to irrigate the plots. The pumped water was recycled — but if it were fresh water transported from the Colorado River, as is much of Southern California water, emissions would be higher, said Townsend-Small. They also factored in the nitrous oxide released from soil after fertilization. Nitrous oxide is a greenhouse gas 300 times more powerful than carbon dioxide, which is released by fossil fuel combustion.

California has no regulations to control turfgrass, but the study “shows the importance of full life-cycle analysis for greenhouse gases,” said Mary Nichols, head of the California Air Resources Board, which is charged with reducing the state’s carbon footprint. Research is underway, she noted, to develop varieties of grass that need less mowing and use less water.

What about the heat island effect, the vaunted benefit of plants as a way to cool cities? “Irrigating trees in urban Southern California reduces the heat island effect,” said Stephanie Pincetl, author of “Transforming California: A Political History of Land Use and Development.” “But lawns have no such benefits, and also contribute to water pollution because they are heavily fertilized.”
Townsend-Small said that turf emissions vary according to region. Studies would need to be done in wetter northern climates. There, she said, grass might not need irrigation, but it would also store less carbon during cold winter months.

For Southern California residential lawns, she noted, using rakes rather than leaf-blowers and hand mowers rather than gasoline-powered equipment would improve their carbon footprint.

“About 40% of the drinking water we import at great financial and environmental expense is used for outdoor irrigation,” said Paula Daniels, an L.A. Department of Public Works commissioner. “This study hopefully will motivate more of us to make changes in our landscapes.”

–Margot Roosevelt

ISSUED BY: THE DEPARTMENT OF WATER AFFAIRS
DATE: 20 January 2010
DROUGHT CONDITIONS PERSIST
The Department of Water Affairs has prioritized support for parts of the
country affected by the prevailing drought conditions due to low rainfall during
last year (2009). According to statistics gathered by the Department, George in
the Eden District Municipality in the Western Cape experienced the lowest 12
consecutive months of rainfall since 1921 and is considered severely dry. The
current conditions started around the month of March 2008.
Having received an annual rainfall of 477mm in the last year which accounts for
only 63 percent of the areas Mean Annual Precipitation (the average amount of
rainfall received annually), urgent measures had to be put in place to deal with
the water shortages including the introduction of severe water restrictions,
sewage water is being re-directed to the purification plants and sea water is
being desalinated to augment supply.
In addition the water storage levels for this area are well below average and
are declining further. The Garden Route Dam: Storage is 30% which is 70%
below the median storage. The Wolwedans Dam: Storage is 37.1% which is 60%
below the median storage and also gradually declining.
Certain parts of the Eastern Cape are under severe pressure and are also
experiencing severe drought conditions; these include Uitenhage under the
Cacadu district municipality, which received a total rainfall of 360mm from
January to December 2009, accounting for only 69 % of its average annual
rainfall. Other affected areas are Grahamstown and Somerset East (Cacadu
District Municipality), Kei Mouth (OR Tambo District Municipality) and Hogsback
(Chris Hani District Municipality) as well as Phalaborwa in the Limpopo
province.
Mava Scott, spokesperson for the department says the Minister’s visit to areas
like Adelaide and Kuruman this week was part of a nationwide drive to find
creative solutions and interventions in the short to long term provision of water
to these communities. “these interventions include soliciting funds to
commission drilling for water/boreholes in the short term, recycling of sewage
water in the medium term but also very importantly the upgrading of the
existing water schemes” he said.
The delivery of water tankers to villages who experienced severe water
shortages in December in the Zeerust area by the Minister constituted one of
these measures to respond urgently to the drought conditions.
Also of critical importance was the issue of water conservation and demand
management especially in these drought stricken areas. Mr Scott added that
consumer behavior in the use of water can go a long way in addressing the
issue of water provision to the communities.
During the 2009 year most parts of the country received normal to above-normal
rainfall with the exception of the southern parts of the Western and Eastern Cape
Provinces, the western parts on the North West Province, the south-eastern parts of
the Limpopo Province and small areas over northern KZN.
The Department of Water Affairs is closely monitoring the situation. Interventions are
being implemented and finalized in other areas. Water Conservation and Demand
management initiatives have been ongoing and these will be intensified.

With over 3000 installations in South Africa, Water Rhapsody is fiercely protective of its loyal base of customers. Should any of our customers be unhappy with our products and service, we would be the first to know, and very quick to respond. Fortunately with our very robust products, we do not often hear from our customers for many years after installations, but some have expressed their sentiments including Prof. Kader Asmal and Simon Nicks and we are publishing these to our Water Rhapsody “Customers” page.
In rolling out our franchises, Water Rhapsody are represented in all provinces, except Free State, North West and Northern Cape at this point in time. With strong demand for our water conservation systems from Gauteng, Eastern Cape, Western Cape, KZN and Mpumalanga, we have concentrated on these provinces first and now need to consolitate in these regions. Our vision is to have a Water Rhapsody system in every home in the future.