AGR638 C1

• Precision agriculture


  A systems approach for site-specific management of crop production systems

  
• Precision agriculture


  • Managing each crop production input (fertilizer, limestone, herbicide, insecticide, seed etc.) on a site-specific basis to reduce waste, increase profit and maintain the quality of the environment
  • Also called site-specific crop management (SSCM)

  
• In conventional farming, fields are treated uniformly
• Crops and soils are not uniform but vary according to spatial location

  
• Site-specific crop management (SSCM)

  Taking advantage of spatial differences within a field, for example, by applying less fertilizer to areas that receive less rainfall (and therefore have lower yield potential) and more to areas that receive more rainfall (and therefore have higher yield potential)
• The concept of PA by treating small areas of a field as separate management is not new
• C.M. Linsley and F.C. Bauer published Circular No. 346 from the University of Illinois describing a procedure for sampling soil and preparing maps to guide the application of lime on a spatially variable basis


  1929
• The concept of PA applies to many agricultural operations, e.g., variable application rates for seed, fertilizer, or pesticides
• What made the concept of PA feasible

  • Invention and availability of new technologies
  • As agriculture become mechanized, farmers began to treat whole fields as the smallest management unit
  • Today, technology has reached a level that allows a farmer to measure, analyze and deal with in-field variability that was known to exist previously but was not manageable

  
• Precision agriculture


  Also called site-specific farming or farming by foot, representing the ability to collect data and make decision on an smaller than an entire field

  
• In the past, decisions were based on data collected and averaged for an entire field
• Precision agriculture


  A management strategy that uses information technologies to bring data from multiple sources to bear on decisions associated with crop associated

  
• Precision agriculture


  • Obtaining data an appropriate scale
  • Interpretation and analyses of the data
  • Implementation of a management response at an appropriate scale and time

  
• Yield was calculated for the entire field and nutrient in the soil was estimated for the entire field, assuming each acre in the field had the same value
• The ability to mark off or identify a small area of a field (a subfield) for data collection allows us to be more precise and accurate with our decision making
• These subfields may be a grid of squares that arbitrarily divide the field, or they may be a series of homogenous areas that have been determined to be significantly different from surrounding areas
• By collecting and analyzing data from subfields, decisions that might not be appropriate for other areas of the fields can be made
• Spatial variability


  • The driving force of precision agriculture
  • Without variability, there is no need to divide a field into subfield areas
  • Variability occurs throughout the natural environment due to the way soil developed under prairie grass, forests, glaciers or floods

  
• Variability


  • Canopy size (m3) from ultrasonic sensors
  • Irrigation networks of sensors to control and optimize water use

  
• By using subfield areas, the producer can identify variability and implement management practices to each subfield
• Soil type defines much of the variability within an agricultural field, with each soil type representing a homogenous area of unique characteristics
• Being able to record and map this variability allows the producer to analyse and make use of it in decision making
• Management efficiency in precision agriculture

  The ability of the producer to use precision agriculture technology for fundamental management of the operation

  
• Decision-making efficiency in precision agriculture

  The ability to use financial and production records and the farmer's knowledge base to make an objective decision

  
• Broadcasting a constant amount of fertilizer is inherently inefficient due to variability, with some areas receiving inadequate amounts, some areas receiving excess, and only a fraction receiving the correct amount</b>
• Variable rate application allows the farmer to place a specified amount of product on a particular area of a field
• Technology


  • The single most important aspect of precision agriculture
  • The entire process of data collection, data analysis, and implementation on a subfield basis requires technology such as handheld computers, controllers, monitors, sensors, GPS and communication devices

  
• Benefits of precision agriculture

  Environmental benefits - Ability to reduce or strategically place inputs to reduce impact on natural resources

  Economic benefits - Decisions that result in higher monetary return, more income, or lower operating costs