Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Record number 356904
Title Testing the spatial significance of weed patterns in arable land using Mead's test
Author(s) Heijting, S.; Werf, W. van der; Kruijer, W.T.; Stein, A.
Source Weed Research 47 (2007)5. - ISSN 0043-1737 - p. 396 - 405.
Department(s) Crop and Weed Ecology
Mathematical and Statistical Methods - Biometris
Publication type Refereed Article in a scientific journal
Publication year 2007
Keyword(s) horizontal movement - populations - cultivation - stability - seeds - maps
Abstract There is a need in weed science for statistical tests for patchiness and spatial pattern. The objective of this study was to investigate the performance of Mead¿s test for detecting patterns in synthetic data and in real weed counts made in maize, and making a first assessment of its applicability in ecological studies on weeds. In an extension to Mead¿s test, made here for the first time, we merge original quadrat count data into rectangular cells of m by n quadrats. Care was taken to rule out the effect of starting point on the test result. Using the synthetic data, we demonstrate the ability of the test to detect both patchiness and homogeneity as deviations from randomness. The first deviation results in right-sided significance, and the second in left-sided significance of the test. Analysis of the real weed patterns demonstrated patchiness at many scales for five of the six investigated species and lack of any deviation from randomness in the sixth: Taraxacum officinale. The latter was the only wind dispersing species in the dataset. No deviation towards homogeneity was found in any of the real weed species at any scale. All patchy patterns showed anisotropy, being elongated in the direction of field traffic. As it turns out, Mead¿s test is well suited to detect departures from randomness in observed weed patterns and enhances the suite of diagnostic tools that can be employed by weed ecologists
There are no comments yet. You can post the first one!
Post a comment
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.