Agriculture Reference
In-Depth Information
Year
1989
1990
1991
1992
1993
1995
1997
1999
2001
2003
Axis 1
Figure 7.4
. Changes in species composition in the first decade following abandonment of
agricultural practices in the Early Successional system of the MCSE. Data are for each of
6 replicate plots with year indicated by different symbols. Species composition compared
using non-metric multidimensional scaling (NMDS) analysis of annual biomass harvest
averaged across 4-5 sampling stations in each replicate (see Gross and Emery (2007) for
details). From
Old Fields
, edited by Viki A. Kramer and Richard J. Hobbs. Copyright © 2007
Island Press. Reproduced with permission of Island Press, Washington, D.C.
of native-dominated communities in the surrounding landscape (Burbank et al.
1992, Foster 1999, Gross and Emery 2007) as dispersal limitation can be an impor-
tant controller of diversity in abandoned fields in this region (Suding and Gross
2006a, b; Houseman and Gross 2011). The introduction of spring burns to con-
trol colonization by woody species in this system (1997) has had no effect on the
establishment of native species (Gross and Emery 2007) or on the composition of
these communities (Dickson and Gross 2013). This is consistent with results from
Suding and Gross (2006b) who found that only when seeds of native species are
added to burned areas is there an increase in recruitment of native species. Fire may
have promoted the convergence (greater similarity) in species composition among
replicates (Fig. 7.4) by selecting for species that were favored by annual burning,
but did not promote native species recruitment (Gross and Emery 2007). Native
C
4
grasses that are consistently favored by annual burning in other midwestern
