Wildfires cause tragic losses to life, property, and the environment. But even after the fire rages, the damage is far from done. Without vegetation, bare, burnt soil lies vulnerable to erosion, which can impede efforts towards natural forest regeneration.
Now Assaf Inbar, a graduate student at Tel Aviv University's Porter School of Environmental Studies, together with his supervisors Prof. Marcelo Sternberg of the Department of Molecular Biology and Ecology of Plants, Dr.Meni Ben-Hur of the Volcani Center and Dr. Marcos Lado of the University of La Coruña, Spain, have studied a new soil protection procedure that may significantly reduce erosion in areas ravaged by forest fires. Working with an organic polymer originally used in agriculture, Inbar and his supervisors have tested their method in the lab and also in Birya forest in Israel, large parts of which have been burnt by fire.
Protecting the soil from erosion, says Inbar, is vital for the quick restoration of the vegetation. And this method can be cheaper than current solutions, such as creating log barriers or mulching, a process in which the ground is covered with woody chips or straw.
The research was presented at the Israel Society of Ecology & Environmental Sciences Annual Conference in 2010 and at a COST–European Cooperation in Science and Technology Conference in 2009.
Holding on to the soil
Following a wildfire, soil often erodes because vegetation is burnt and the soil remains bare. Deprived of the protection from the elements that vegetation provides, soil can't absorb intense rains, causing run-off. "If water cannot penetrate the soil, it flows on top — taking the soil with it," says Inbar. The danger is especially great in forests with steep slopes and shallow soil. Once significant amounts of soil wash away, it is difficult to reforest the area.
The researchers turned to the anionic polymer Polyacrylamide (PAM), widely used in agriculture to prevent soil erosion. They tested the polymer on samples of burnt soils both in the lab, using a rainfall simulator, and out in the field under natural rainfall, using run-off plots in an area of Birya Forest that had been exposed to a moderate wildfire. The run-off plots were placed on a 40-degree slope and outfitted with a funnel at the bottom to collect run-off and sediments, measured after every rainstorm.
In both simulated and natural rainstorms, the burnt soils remained much more stable with the addition of the PAM than without, reports Inbar. With the addition of the polymer, applied in granules of about 110 pounds every 2.5 acres, soil erosion was reduced by 50 percent.
Helping the forest to bloom again
At just under $1.50 dollars per pound, PAM granules can be an affordable alternative to mulching, which sometimes requires application by helicopter, and to log barriers, which requires the effort of many workers and heavy machinery. What's more, the non-toxic PAM is safe for existing vegetation.
The researchers have tested the soil's ability to nurture vegetation with the addition of the polymer, and saw encouraging results. They used wheat as a model for annual plants that sprout during the rainy season in areas that had been affected by fire. The polymer had no negative impact on the growth of the wheat, concludes Inbar, who says the researchers' next step is to test different soils, the interaction between the polymer and ash, and the effectiveness of this treatment in larger areas.
George Hunka | EurekAlert!
Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University
New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine