HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by Brock, A. Articles by Hofmann, B. S. Search for Related Content PubMed Articles by Brock, A. Articles by Hofmann, B. S. Agricola Articles by Brock, A. Articles by Hofmann, B. S. Related Collections Soybean Field-Scale Studies Spatial Variability Site-Specific Analysis Maize Management

Defining Yield-Based Management Zones for Corn–Soybean Rotations

Department of Agronomy, 3351 Lilly Hall of Life Sciences, 915 W. State St., Purdue Univ., West Lafayette, IN 47907-2054

View larger version (16K): [in a new window]   Fig. 1. Fuzziness performance index (FPI) values shown as a function of the number of management zones (MZs) for (a) corn yield-based (CYB) MZs, (b) soybean yield-based (SYB) MZs, and (c) combined crop yield-based (YB) MZs.

View larger version (16K): [in a new window]   Fig. 2. Normalized classification entropy (NCE) values shown as a function of the number of management zones (MZs) for (a) corn yield-based (CYB) MZs, (b) soybean yield-based (SYB) MZs, and (c) combined crop yield-based (YB) MZs.

View larger version (22K): [in a new window]   Fig. 3. Two measures of yield variance reduction resulting from delineation of experimental fields into two to six zones using both corn and soybean yield data. Data points are the means for both crops in all experimental fields. Error bars show the 95th percent confidence interval.

View larger version (37K): [in a new window]   Fig. 4. The two measures of yield variance reduction for (a, b) corn yield-based (CYB) management zones (MZs), and (c, d) soybean yield-based (SYB) MZs shown as a function of the number of MZs. Data points are crop-specific means for the experimental fields that did not differ significantly. Error bars show the 95th percent confidence interval.

View larger version (47K): [in a new window]   Fig. 5. Deviation of management zone (MZ) mean relative yield from whole field means following delineation of fields into four MZs. Data are show for (a–c) corn and (d–f) soybean for the three zone delineation strategies including (a, d) corn yield-based (CYB) MZs, (b, e) soybean yield-based (SYB) MZs, and (c, f) combined crops yield-based (YB) MZs. Within a field, columns topped with the same letter are not significantly different (p > 0.05).

View larger version (106K): [in a new window]   Fig. 6. Distribution of soybean yield-based (SYB) management zone (MZ) rankings within each rank of corn yield-based (CYB) MZs and distribution of CYB MZ rankings within each rank of SYB MZs. Data are shown for four MZ delineations in each field; stacked bars show percent of observations within a MZ ranking that were identified as high (H), medium high (MdH), medium low (MdL), and low (L) yield by the alternate delineation strategy.

View larger version (84K): [in a new window]   Fig. 7. For four management zone (MZ) delineations, distribution of corn yield-based (CYB) and soybean yield-based (SYB) MZ rankings within soil map units in a field. Rankings, based on MZ mean relative yields, were high (H), medium high (MdH), medium low (MdL), and low (L).