Submitted to: Agronomy Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/6/2002
Publication Date: 1/20/2004
Citation: Fridgen, J.L., Kitchen, N.R., Sudduth, K.A., Drummond, S.T., Wiebold, W.J., Fraisse, C.W. 2004. Management zone analyst (MZA): Software for sub-field management zone delineation. Agronomy Journal. 96:100-108. Interpretive Summary: Farmers using combines with yield monitoring systems for creating yield maps have realized that yield differences can be extreme within fields. This has motivated farmers to plan sub-field management zones so that inputs can be varied according to crop need. In order to do this, they have requested decision aids that can help identify sub-field management zones. This paper reports on a software program that we developed using a "clustering analysis" procedure to create management zones. The program is called Management Zone Analyst (MZA) and is available free to the public at http://www.fse.missouri.edu/ars/decision_aids.htm. MZA was developed using Microsoft Visual Basic 6.0 and operates on any computer running Microsoft Windows (95 or newer). An advantage of MZA over many other software programs is that it provides concurrent output for a range of potential management zones so that the user can evaluate the number of areas into which a field should be partitioned. This is accomplished by the use of two clustering performance indices which is shown in graphical form after performing MZA clustering. The best number of zones is achieved when these indices are at their lowest value. An example of MZA output is provided for two Missouri claypan soil fields using soil electrical conductivity, slope, and elevation as the variables for creating the management zones. The results showed that these two fields should not be divided into more than four management zones. We expect producers and crop consultants will find MZA useful in creating site-specific management plans.
Technical Abstract: Producers using site-specific crop management (SSCM) have a need for strategies to delineate areas within fields that management can be tailored for. These areas are often referred to as "management zones." Quick and automated procedures are desirable for creating management zones and for testing the question of how many zones to create. A software program called Management Zone Analyst (MZA) was developed using a fuzzy c-means unsupervised clustering algorithm that assigns field information into like classes, or potential management zones. An advantage of MZA over many other software programs is that it provides concurrent output for a range of cluster numbers so that the user can evaluate how many management zones should be used. MZA was developed using Microsoft Visual Basic 6.0 and operates on any computer running Microsoft Windows (95 or newer). Concepts and theory behind MZA are presented, as are the sequential steps of the program. MZA calculates descriptive statistics, performs the unsupervised fuzzy classification procedure for a range of cluster numbers, and provides the user with two performance indices [fuzziness performance index (FPI) and normalized classification entropy (NCE)] to aid in deciding how many clusters are most appropriate for creating management zones. Example MZA output is provided for two Missouri claypan soil fields using soil electrical conductivity, slope, and elevation as clustering variables. MZA performance indices indicated one field should be divided into either two (using NCE) or four (using FPI) management zones, and the other field should be divided into into four (using NCE or FPI) management zones.