If there has been one constant in agriculture over the years, it has been the need to maximize yield for a given space of land. Farmers have long known that due to varying drainage and soil properties, different parts of an individual field require different levels of input. Enter the wonders of technology to bring about precision farming, also called site-specific farming, to adapt elements such as seed, fertilizer and pesticide to the varying needs of an individual field.
Farmers have recognized variability in their fields for years, says Sam Parsons, an associate professor in the Department of Agricultural and Biological Engineering at Purdue University. And many of them, especially when the farms were smaller in size, practiced a type of precision farming. But they had to do it on a manual basis. It is only within the last few years that technology has caught up with the concept. Farmers are now able to manage individual areas of their fields more accurately.
Two innovations in particular have allowed farmers and agricultural engineers to manage fields more precisely: 1) the availability of Global Positioning Systems (GPS) to the general public, and 2) the introduction of instantaneous yield monitors.
GPS uses a system of satellites to provide users with accurate information about their position and velocity anywhere in the world. Developed by the U.S. military during the 1970s and 1980s, GPS was not available to the general agricultural community until 1992, but it had an immediate impact on precision farming.
GPS allowed us to accurately record and map the location of soil and crop variances in a given field, says Russell Hahn, the former director of standards and technical activities with the American Society of Agricultural Engineers. Without it, precision farming as we know it would not have been possible.
Around the same time that GPS was applied to precision farming, agricultural equipment companies such as John Deere; New Holland, N.V.; and Case Corp. came out with yield monitors, which allow farmers to record variances in field yield as they harvest their crops. These monitors gave farmers a new way to measure and adapt for variances within a given field. We have always had soil maps, says Parsons. But the development of yield monitors coupled with the availability of GPS allowed us to start to look at variability within fields based on yield levels, and to adjust the application of agricultural input accordingly.
Agricultural engineers and computer scientists are making advances with many other systems that will allow for more accurate applications of precision farming. Here are a few of the most significant:
- Electrical conductivity. Several methods using electrical conductivity are being employed to estimate topsoil depth, organic matter variations and other parameters. Some of the more popular systems currently in use include the EM-38, being tested by the University of Missouri, and the Veris system. This technology provides farmers and engineers with more detailed soil type mapping.
- Remote sensing refers to a process of obtaining information about land or water without any physical contact between the sensor and the subject of analysis. It involves measuring spectral variability in light reflectance from satellite-, airplane- or ground-based spectral scanners. Using this technique, scientists can analyze large and small segments of soil, and measure changes in such variables as soil type, soil moisture and organic matter content over a given period of time.
- Sensor development. Scientists are developing an array of sensing equipment that can be used to measure a variety of field factors. For example, the SPAD meter estimates crop chlorophyll content and detects areas of a field lacking in nitrogen in time to reduce field loss. Another type of sensor is the cardy meter, which is a hand-held electronic tool that estimates nutrient status is a field. Other sensors estimate variability in organic matter and adjust herbicide application rates accordingly.
The benefits of precision farming are threefold. It helps farmers reduce costs by allowing them to apply fertilizers, pesticides and other agricultural inputs only where they are needed. It helps farmers increase yield by insuring that each area of a field receives the input elements that will create the greatest yield. Finally, it benefits the environment by lowering the total amount of pesticides and fertilizers applied to a field.
Precision farming maximizes production in a way that minimizes the cost of inputs as well as any detrimental effects on the environment, says Parsons. I think it offers tremendous opportunities for engineers.
Glen Rains, an assistant professor with the University of Georgia Biological and Agricultural Engineering Department, also believes that precision farming offers good opportunities for engineers, but he doesnt think the job market is as strong as it might be. This area isnt growing as fast as it could be because of the current farm economy, Rains says. [Precision farming] involves a tremendous amount of data collection to help you manage your farm. But it takes maybe three, four or five years of data to really see the benefit. And when you are in the crunch to make money so that you can farm just the next year, its tough to invest in precision farming, because it is an investment in time and in money to get involved.
Because of the downturn in the farm economy, Rains believes that the growth of precision farming divisions for most of the larger agricultural equipment companies has slowed. However, he notes that ample opportunities still exist with some of the smaller companies. Because agriculture is having such a tough time of it now, fewer resources are being invested in precision farming by some of the larger companies, he says. But there are some smaller companies that are growing by developing markets for yield monitors, variable rate applicators and other types of technology. Right now, the best opportunities may be with these types of companies.
Engineering and computer science students interested in careers in precision agriculture should keep their eye on the market. The farm economy can improve rapidly and career opportunities along with it.
Another area of agricultural engineering that is growing is bioengineering. Bioengineering refers to the application of engineering in which biological elements are critical aspects of the design. Many bioengineers work for agriculture products and processing companies to develop more efficient processes for creating both new and better products from agricultural output.
Bioengineering has grown rapidly over the last few years. Mark Riley, an assistant professor in the University of Arizonas Department of Agricultural and Biosystems Engineering and chair of the biological engineering division at ASAE, believes there are several reasons for this.
A lot of the growth has to do with improvements in technology, Riley says. We know better how to get a biological system to do what we want it to do, how to better grow plants in controlled environments and how to use cultured animal cells to make useful proteins. Another big boost is that companies that have been struggling for years in the biotechnology area are now bringing products to market. The people who make these products and actually manufacture them are biological engineers.
According to Riley, one of the more important technological advances in bioengineering has occurred in the use of applied enzymes. Agricultural engineers are now using applied enzymes to make healthier food products by converting fats to something that doesnt cause the same health concerns as some natural fats do, Riley says. Most of the new cleaners that are antibacterial/antimicrobial are made using enzymes. ... And there are some detergents that get rid of proteins and fats very easily because of the enzymes that have been placed in them.
Another cause for expansion in the bioengineering industry is research involving genetically modified plants. As Hahn points out, bioengineers do not genetically alter the plants, but they are often the ones that conduct research on the plants once they are created. Riley agrees, Biological engineers find out how much water and how many nutrients the plants need, as well as what kind of pesticides, he says. They also develop models of what the potential health hazards of these plants are, as well as what the possible hazards to the environment may be. I think its going to be an area of growth because a tremendous number of the crops grown in the United States today are genetically modified.
Lately, there has been a lot of debate regarding the safety of using genetically altered crops. Riley believes that biological engineers may help keep the debate on an objective and scientific level. My hope is that biological engineers will help bring up the education level and the scientific knowledge of these debates, he says.