Climate Change Threats
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Australian continent stretches across multiple latitudes, approaching equator and bumping into various ocean currents as well as wind systems, which results in the rangelands of itself being easily exposed to global warming and other climate changes (Frakes, 1987). With this crisis at hand, yet already being overgrazed by introduced livestocks and cleared for residential purposes, the Australian endemic grasslands along with numerous fauna is at stake, which in turn significantly reduces grassland biodiversity (Howden, 2003). A. parapulchella is the most vulnerable species to this predicament, as described above, their physical structure give them a relatively low mobility for dispersal and seeking refuge, and their ecology has decided that their wellbeing is entirely depending upon native vegetation and food resources.
Furthermore, there are two threats that would cause significant reduction to A. parapulchella’s population. One is bushfire and drought that has become more and more frequent and dramatic in recent years. This is associated with the El Nino effect that exerted upon Australia ever since 2002 (Steffen, 2006) which indicates a drier and hotter future. Combining this aspect with rising temperature and prolonged drought, the risk of fire will be higher than usual (Downie, 2006). In this case, grasslands that are basically natural fuel will be induced to burn out, causing habitat loss of A. parapulchella. Another problem is the invasion of exotic weeds. Upon European settlement, invasive weeds have been spreading all over Australia, so it is well confirmed that this process is largely accompanied by anthropogenic behaviours. However, the rapid growth of weeds was also linked with microclimate which was directly connected to the global warming as well as other subtle climate change (Adair & Groves, 1998). What’s more, with clearing up native vegetation cover, exotic weeds have more change to out-compete native fauna like Kangaroo grass that is inseparable from the ecology of A. parapulchella. Consequently, the foreseeable domination of invasive weeds would lead to the incompletion of A. parapulchella’s life-cycle and thus accelerate their extinction speed. |