Are We Destroying Our Insurance Policy? The Effects of Alien Invasion and Subsequent Restoration - Landscape Ecology for Sustainable Environment and Culture - page 349

Table 16.3 The extent of the
Black Wattle alien invasion
clearing by Working for
Water along the Kromme
River from 2002 to 2010

Years Area cleared (ha/a)

2002 93.61

2003 57.18

2004 77.19

2005 155.79

2006 143.7

2007 149.24

2008 147.08

2009 151.89

2010 269.39

Mean 138.3411

(Fig. 16.22 ). However if palmiet was restored further downstream, services that
are crucial to downstream stakeholders -including water purification and flood
attenuation, may be recovered with time (Aronson et al. 2007 ; Blignaut and
Aronson 2008 ).
In an attempt to restore the Kromme Catchment, Working for Water is clearing
Black Wattle at three times the average rate of invasion. However the available
data do not differentiate between initial clearing and follow-up, so it is possible

Fig. 16.22 The headwaters of the Kromme River are in a pristine condition as they fall within
the Formosa Nature Reserve, Eastern Cape, South Africa