multivariate poisson hidden markov models for analysis of spatial ...

common species are Wild Oats (named as species 1509) and Wild Buckwheat (named
as species 1097). Dandelion (named as species 1213) is less frequent. In the subsections
of 4.2 give a description of each weed in the study. Figure 4.1, Figure 4.2, and Figure
4.3 and facts given in these sections are obtained from the Weed Identification Library
(University of Manitoba, Department of Plant Science, 2005).
4.2 Weed species composition
There are differences in the species composition (richness and abundance) of the weed
community depending on the type of fallow that preceded the cultivation phase. Note
that there are some dominant species as well as abundant weed species present in these
fields (Ngobo et al., 2004; Akobundu, 1999; and de Rouw, 1995). This dominant and
abundant behaviour can be due to several reasons, such as species composition in fields
and soil parameters, as well as some other environmental factors. The variation in weed
species composition and abundance during the cropping phase is related to the physical
and chemical characteristics of the soil. The physical and chemical soil properties are
significantly correlated to the weed species composition (Ngobo et al., 2004).
Unfortunately for this research, the background information of the fields is not
available.
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