This will be the last point of this section, before shifting to more of an opinion based look into the future human practices. Thus far, I’ve ventured from land, to wetland and then out to sea, but now I want to look at change as a whole. As most people would be aware, many species rely on environmental cues as part of their yearly cycle. This is everything from first bloom or chrysalis to a migration that spans many thousands of kilometres. In all ecosystems, there are many services that are provided by a species to other species which is paramount for the receiving species fitness if not local persistence, which includes nutrient, mineral and energy transfer (Traill et al. 2010). In extreme examples this is called symbiosis; where the relationship can be complex, resulting from a long co-evolutionary relationship (Hill, 2009). There are interactions that involve these environmental cues (eg. pollination, migration) that human activity is benefited by (Traill et at; 2010).
As was highlighted in part 4, there is a noticeable global warming trend, which should be evident in a change in species response to a change in timing of these cues.
Response to change
Rosenzweig et al. (2009) looked at data sets from more than 28,800 biological and 829 physical systems with collections from 1970 to 2004 and found that around 90% of changes observed in the former group and 95% of changes in the latter group were, at a global scale, the expected result due to global warming. Of the ~80 studies (>29,500 data sets), only 3 studies (9 data sets in 4 cells) showed that the results are due to other anthropogenic drivers (ie. land use changes, harvest and pollution) (Rosenzweig et al. 2009). Rosenzweig et al. (2009) also state that it is highly likely (>90% probability) that the observed warming is the result of anthropogenic modified greenhouse gas concentrations.
A similar study was carried out in the UK by Amano et al. (2010), where data of first bloom from 405 plant species, spanning 250 years was analysed. This study showed an average 5 days earlier of flowering for every 1 degree C increase (Amano et al. 2010).
As different species will react to different cues, such as climate cues (eg. ice melt, rainfall changes and temperature) or non-climate cue (day length), it can be argued that as climate changes increase, inter-species relationships will be stressed due to shifts in timing (Brook, 2009). The greater the reliance of a species on another on a lower trophic level would determine the need to respond as peaks of that food supply shift due to climate change (Brook, 2009).
Failure to meet this change, as with all those previously discussed, would reduce fitness and lead to a reduction of biodiversity. Where it is generally believed that ecosystems are more resilient to shock when biodiversity, or at least key species are maintained (Fischer et al. 2006), all that has been discussed in previous chapters has demonstrated potential for species loss, thus exacerbating degradation of those ecosystems and certainly causing detrimental impacts on other systems that rely on those services – including our own species (Traill, et al. 2010).
Indeed, what I notice on the road already is more opportunistic farming (many farmers following the recent big rains) and a change in crops (mostly a removal of vineyards). As much as 60% of crops rely on natural pollination, not to mention the vast amount of soil conditioning and pest control and other services provided by the local ecosystem (Traill et al. 2010), it seems naïve to me to assume such opportunistic farming can remain viable under both a continuous loss of biodiversity and changing climate.
This brief example of farming is in essence my reason for writing this collection. In far too many ways, our species has developed quicker and more efficient ways to achieve the results of work. This has lead to a society unimaginable several generations ago. It has lead to an average standard of living greater than that ever known before and without a doubt has increased our potential to ever greater heights. This has, however, caused a nasty side-effect of an entirely new form of ignorance and certainly elements of gluttony.
I don’t wish to harp on, like some Tolkien nightmare of the machine, for I am happy with what we have created and that it will give my son opportunities that his ancestors, who landed in South Australia in the 1870’s, could never of dreamed of in their comparably harsh venture to establish this place as a state. On the other hand, they saw species on their plot that my son will never see. As much as we have come along way, especially over the past two centuries, we’ve also forgotten our roots and humility for a much wider world than just the cities that we have built. On a much more modern note; the more that we understand ecology and biological properties, the more we will be able to exploit such services at a reduction of economic outlay and energy. It is likely that the answers to many diseases and food source issues will be resolved through such understand, but this will be remain a decreasing likelihood as species loss and climate change continue to be ignored.