Click on “Download PDF” for the PDF version or on the title for the HTML version.
If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.
Combining Compost Application and Soil Solarization for Control of Soilborne Plant Pathogens
Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org
Citation: Paper number 032264, 2003 ASAE Annual Meeting . (doi: 10.13031/2013.14969) @2003
Authors: Megan N. Marshall, Jean S. VanderGheynst
Keywords: Bioreactors, composts, microbial activity, oxygen, organic farming, pest control, plant pathogens, plastic film, self-heating, soil solarization, waste utilization
In soil solarization, moist soil is covered with transparent plastic tarps, resulting in passive
solar heating of the soil and a pasteurization effect, which reduces plant pathogen populations
without the use of chemical pesticides. By combining compost application and soil solarization, there
is the added benefit of utilizing organic wastes and the potential for decreasing the duration of
solarization treatments. Compost stimulates microbial activity in the soil, which may lead to heat
generation by aerobic microorganisms, higher soil temperatures, and thus more rapid thermal
inactivation of pathogen populations.
(Download PDF) (Export to EndNotes)
The objective of these initial laboratory studies was to assess the potential for compost incorporation
to produce higher soil temperatures during solarization. These studies were carried out using
insulated 1-L bioreactors, which were placed in an incubator to approximate diurnal soil temperature
fluctuations typically achieved during solarization. Bioreactors were filled with soil mixed with
compost substrates at various loading rates (0, 2% (v/v), or 10% (v/v)). Oxygen was supplied to
bioreactors through humidified airflow or by diffusion through a piece of solarization plastic.
Temperatures in aerated bioreactors with compost substrates were up to 3-10 C higher than
bioreactors with soil alone. Increased respiration in aerated bioreactors with compost substrates
suggested that increased temperatures were related to increased aerobic microbial activity.However, the temperature of bioreactors receiving oxygen by diffusion through solarization tarp was
not greater when soil was amended with compost substrates.
These results show the potential for compost addition to increase soil solarization temperatures by
increasing aerobic microbial activity, if sufficient oxygen is available. Future experiments will focus
on variables that influence soil oxygen content during solarization, such as soil moisture content,
compost loading rate, and compost stability. New bioreactors are under construction that will provide
oxygen to the soil only by diffusion through solarization plastic, will measure temperature more
accurately using thermistor probes, and will characterize the oxygen limitation by measuring redox
potential in soil and oxygen concentration in headspace.