 Agriculture
researchers, agronomists and other extension specialists now have access
to relatively simple tools that will make it easier to measure changes
in greenhouse gas emissions brought about by improved crop and livestock
management practices.
PHOTO: Technician collects an air sample in
the field to be analyzed for greenhouse gas content.
Being able to measure and quantify changes in gas
emissions will provide tangible evidence to the frontline forces that
improved production practices do make a difference.
One of the four types of monitoring kits being worked on
by a Nova Scotia researcher is a Soil Greenhouse Gas Monitoring Kit,
that can be used to properly collect gas samples in the field for later
analysis in the lab.
The kit can be used by a trained technician, for
example, to collect gas samples to measure how much carbon dioxide,
methane or nitrous oxide – three common greenhouse gases – is released
after various demonstration treatments.
“The value is that people involved in research and
demonstration projects will be able to collect gas samples as the work
is being done,” says Dr. David Burton, research chair in climate change
at the Nova Scotia Agricultural College in Truro. “Now we will not only
be able to say a certain practice makes a difference in greenhouse gas
emissions, we will be able to quantify it.”
The kits are being developed in a collaborative effort
between Burton and Dr. David Lobb, Associate Professor, Department of
Soil Science, University of Manitoba.
The four kits in this project include the greenhouse gas
monitoring kit, a Soil Quality Monitoring Kit, which was actually
developed by the U.S. Department of Agriculture (USDA), a Soil
Environment Monitoring Kit, with components similar to a weather
station, and a Soil Carbon Monitoring Kit. The gas monitoring kit, the
soil quality kit, and the environment monitoring kit are completed and
ready for use. Burton still has a few technical bugs to work out of the
carbon monitoring kit, but hopes to have it ready later this year.
PHOTO: Some of the components that go into
field soil and gas monitoring kits.
The field test kits are being developed as part of the
federal Greenhouse Gas Mitigation Program (GHGMP) for Canadian
Agriculture. It’s a national program designed to demonstrate a wide
range of good production practices, through hundreds of on-farm
demonstration projects in different agricultural sectors, all aimed at
reducing greenhouse gas emissions.
With all these demonstrations being done, it was felt it
would be beneficial to have the tools available to make a range of
measurements.
The $91,500 project received funds from the GHGMP beef
sector, which is administered by the Canadian Cattlemen’s Association,
the GHGMP soil and nutrient management sector, administered by the Soil
Conservation Council of Canada, and the Agriculture and Agri-Food Canada
Scientific Working Group associated with the program.
“We know different management practices will reduce the
level of greenhouse gas emissions, but it is important to be able to
measure those differences,” says Burton. “Our goal was to develop
reliable monitoring kits that can be used by demonstration coordinators
or soil conservation staff in the field.”
The idea is to simplify the testing process. “We’re
talking about kits that fit in a tool box and are carried out to the
field,” he says. “The kits have either the components to produce test
results right in the field, or at least enable the technician to collect
proper samples for analysis.” And you don’t have to be a researcher to
use the kits either, adds Burton. “They are designed so anyone with
training in agricultural science can follow the procedure.”
The USDA-designed Soil Quality Monitoring Kit is being
recommended for use in Canada, rather than reinvent the wheel here, says
Burton.
“The USDA has developed a useful tool box kit that can
be used to measure soil quality features right in the field,” he says.
“It’s a good system. So we’re advising people to check out the USDA Web
site to either buy or build their own kits.” The kit includes tests to
measure soil respiration, water infiltration rate, soil pH, soil
nitrate, electrical conductivity (salt concentration), earthworm
activity, and tests for other soil characteristics.
With the USDA soils kit in mind, Burton and colleagues
launched the project to develop similar field kits to be used to measure
greenhouse gas emissions and other soil quality characteristics.
The Soil Greenhouse Gas Monitoring Kit, developed over
2003 and 2004, has been tested at four sites across Canada. Several of
the mobile kits are in the hands of GHGMP project co-ordinators in
Alberta, Manitoba, New Brunswick, P.E.I. and Nova Scotia for use during
the 2005 field season.
The information obtained from the kits will answer some
of the key questions about how effective management changes are in
reducing greenhouse gas emissions, says Burton. A complete gas analysis
cannot be made in the field, but with proper samples and support
information being collected in the field and sent to university-based
testing labs, reports can be generated in short order.
With basic training a field technician can collect gas
samples to be analyzed for carbon dioxide, nitrous oxide and methane gas
levels. All three are greenhouse gases produced by activities in soils,
and thus impacted through farming practices.
Carbon dioxide is released through the burning of fossil
fuels such as gasoline, and through tillage, which releases carbon
sequestered in the soil to the atmosphere. Methane is released as a
result of anaerobic fermentation, such as occurs in the rumen of cattle
and in liquid manure storage systems. Small amounts of methane are
continuously being consumed by the soil. Nitrous oxide is primarily
released from soils after nitrogen fertilizer application, though some
is also released from manure and fossil fuel burning.
“Our goal is to keep the testing simple,” says Burton.
“A person can take the kit out to a field, collect gas samples every 10
minutes for half an hour and send those samples to a lab for analysis.”
Several Canadian universities, as well as some private labs, have the
capability to complete the analysis and produce a report within a couple
of weeks.
The kits include the chambers needed for collecting
samples, as well as tools for collecting other readings such as soil
moisture and soil temperature. Computer spreadsheets and presentations
are also being developed to assist in the data analysis and
interpretation.
“These kits are designed to measure treatment effects,”
says Burton, noting they are not as extensive as testing involved in
research projects. “We want to measure the difference between no-till
and conventional tillage, or the difference between different manure
application rates and techniques. We’re looking for a comparison of two
different management approaches, so we need an analysis that shows which
treatment is resulting in more greenhouse gas production than the
other.”
The Soil Carbon Monitoring Kit should be ready by the
fall of 2005. This kit will make it possible to get a reading on soil
organic matter right in the field. The level of organic matter directly
relates to the amount of stored carbon.
“Initially we thought about making a kit to be used to
collect samples that could be sent for analysis,” says Burton. “But in
discussions with a number of people across the country, it was felt that
some type of field test for organic matter was preferred.”
While a reliable field testing method is available,
Burton hopes to develop a different process that doesn’t rely on toxic
chemicals. “We have a test in mind that would use a common, safe,
drugstore product but we have to do more field testing to get the
process right,” he says. “However I am quite confident we’ll be able to
make this work.
“This will be a neat process,” he adds. “People will be
able to take it with them on a demonstration field day, for example, and
complete the test for soil organic matter right there in the field.”
The kits will be tested over the next few years to
ensure they produce accurate, reliable results and are user friendly.
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