In today’s world it could be easy to think that the idea of
“sustainability” is a new concept. After
all, it’s been just in the last couple years that we’ve seen an influx in
advertisements and product labels carrying such phrases as “Produced
Sustainably” or “Sustainably Sourced”. But
what exactly does sustainability mean? While
the exact definition is often up for debate and may vary between groups,
commonly referenced principles of sustainability within agriculture include:
- Maintaining or increasing production using fewer inputs
- Adopting strategies or developing new practices that lessen environmental impact
- Seeking continuous improvement in agricultural productivity across the entire supply chain
These principles are far from being new concepts to
Nebraska’s corn farmers who understand that “sustainability” is more than
merely a marketing term. As stewards of
the land, sustainability is a necessity for farmers to meet the increasing
food, fiber, and fuel needs of a growing world, while preserving resources for
all uses and to be enjoyed by future generations.
While principles of sustainability are not new to farmers,
there is always room to improve on what is already being done through new and
innovative methods. This is what
researchers at the University of Nebraska – Lincoln (UNL) hope to achieve with
Project SENSE.
Project SENSE, or Sensors for Efficient Nitrogen Use and
Stewardship of the Environment, is a research project conducted by UNL in partnership
with 5 Nebraska Natural Resource Districts (NRDs) and the Nebraska Corn
Board. Project SENSE seeks to increase
nitrogen use efficiency in corn production and reduce environmental impact of
nitrogen use on groundwater quality by utilizing crop canopy sensors.
Nitrogen is one of the most important elements for plants,
and successful nitrogen management is critically important in optimizing crop
yields. Although nitrogen is naturally
found in air and soil, it’s generally in a form that is not directly available
to most plants, or not available in the amount that plants need. Farmers are able to get around this by
applying the usable form of nitrogen (nitrate or ammonium) to their fields – an
added input expense that doesn’t come without its challenges.
Two of the biggest challenges a farmer faces are determining
the timing of the nitrogen application and the rate to be applied. Nitrogen applied too early holds the risk of
being lost through leaching before the crop takes it up. Leaching occurs because nitrate is not held
well by soil and therefore can be washed below the root zone of plants
especially after large rains. The ideal
time to apply nitrogen fertilizer is during the growing season, just before the
crop’s maximum demand for nitrogen.
However, waiting too long to apply runs the risk of logistic or weather
conditions not allowing application when planned. In addition, due to nitrogen’s complex
behavior of changing between forms and being highly mobile in soil, soil
testing for available nitrogen may give a reading that is only valid at the time
of testing, leading to application rate recommendations that may be too high or
too low for the plant’s needs.
A key component of Project SENSE is the use of crop canopy
sensors to mitigate these challenges.
The sensors are installed on high clearance equipment which allows for
application of nitrogen fertilizer during the growing season of corn when
nitrogen is most needed and taken up by the plant. The sensors themselves measure light
reflectance off canopy leaves which correlates to the nitrogen status of the
crop and is used to generate real-time optimal rates of nitrogen to be applied
as the farmer drives through the field.
In terms of sustainability, the ability to apply the optimal
amount of nitrogen at the right time clearly has the potential to lessen the
environmental impact caused by nitrogen leaching. However, Project SENSE also demonstrates an
often overlooked component of sustainability – economic sustainability. If a production practice can’t be sustained
financially, it won’t be adopted by producers.
The use of sensors to generate the economic optimum rate aims to achieve
stable or increased yields while also using less fertilizer, resulting in
increased profit.
In 2015, 17 Nebraska On-Farm Research Network grower sites
were implemented as part of the project, and preliminary results are promising. At each site, the study compared the grower’s
normal nitrogen management approach to the Project SENSE nitrogen management
approach. Over all sites combined, Project
SENSE resulted in a reduction of nitrogen by 40 lbs/ac compared to the grower’s
nitrogen management approach. Although
an average yield loss of 5 bushels per acre was also observed with Project
SENSE, the economic savings from the reduced nitrogen application translated to
a marginal net return of $7.75 per acre above that achieved using the growers’
standard nitrogen management practices.
Watch the video below or click here for a 360 experience of Project SENSE from inside the applicator cab...
*Tilt or drag to move around!*
For more on Project SENSE and to see full results, visit Nebraska On-Farm Research Network at http://cropwatch.unl.edu/farmresearch
