Penny Thoughts

Tag: australia

Herbert Girardet: Regenerative Cities

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For my final year project I’m investigating what measures are and can be employed in cities to maintain biodiversity. I was recently allocated this and luck would have it, that two days later I get an email saying that Herbert Girardet was coming to Imperial to talk about regenerative cities.

Girardet has worked in urban development for many years and is the co-founder of the World Future Council. He has released numerous books including “Creating Sustainable Cities” and  “Cities People Planet“. He has also directed more than 50 documentaries, working all over the world. All of this and his receipt of the UN Global 500 Award for outstanding achievements in environmental science suggest just how much influence this man has had in the field of sustainable cities over the years.

So as you can imagine, I was pretty excited about going to this talk and therefore, managed to arrive far too early and ended up sat alone in the lecture theater for about 15 minutes before anyone else trickled in.

Girardet was a great speaker and he oozed with the confidence that comes with many hugely successful years in his field. He started by outlining how our cities have developed across the world and how, even though applicable at the time, this type of development cannot continue forever. Delving into the threats that face us now and are inevitably set to worsen in the future, he emphasised the importance of changing the ways our cities function and develop.

Using numerous cities, including Adelaide, Australia, as examples he has been heavily involved in, he showed how cities could be, shifting from a linear system on resources in and waste out, to a more circular system with the regeneration and reuse of resources. I won’t dive into all of these methods Girardet explained but you can find a little more information on this website.

Girardet’s main message has now switched from his previous idea of sustainable cities to regenerative cities, saying that now, simply being sustainable is not enough. We need to start giving back and enabling regeneration of our environment, not just sustaining present levels.

After the talk there was a short Q&A session, but unfortunately there was no time for my question. However, he was hanging around afterwards so I managed to grab him then. He was huddled within a group of students which I managed to barge my way into. I asked him whether he thought that these actions and the move to becoming more proactive than reactive was realistically going to happen before we reach the ever looming point where our effects on our planet are completely irreversible. Unfortunately, like myself, he did not. It’s a rather pessimistic end but people like Girardet have spent the majority of their lives trying to take actions to reduce our effects on the world, however there is only so much scientists can do.

We need big cultural changes across the globe and actions to be taken now rather than when it is too late. One thing I have learnt recently is that scientists need to concentrate efforts on policy makers, politicians and governments before any serious action can be taken to attempt to resolve our greedy attitudes to the world we live in and the resources it provides.

New Hope For Corals: Self-Recovery

study publsihed this week in Science has shown that coral reefs can in fact recover themselves after disaster, when under the right conditions.

Scott reef is an isolated reef found 250km from the coast of Australia in the Indian Ocean.  It suffered a mass bleaching event in 1998 in which over 80% of the coral cover was lost. Dr James Gilmour, the lead author of the study stated that, “The initial projections for Scott Reef were not optimistic”.

Before this paper, it was believed that seriously damaged corals could only recover in the presence of nearby coral reefs. Planula are the gametes of corals; they are what forms when the male and female gametes of the corals fuse together, much like our eggs and sperm. These planula are free-swimming and can reach neighbouring reefs and settle. Before the findings of this study were published, this process was thought to be the mechanism by which damaged reefs could recover.

Scott reef was monitored for 15 years by the researchers and the findings were very much unexpected. The researchers did not have much faith in the reef recovering to its pre-bleaching state in the near future. However, over the years of monitoring they observed the reef recovering at a surprisingly fast rate considering its isolation and level of damage.

Instead of the reef relying on propagules from other healthy reefs, the researchers found that the very few surviving corals were producing planula at high enough rates that self-replenishment was taking place.

It was soon realised that these few survivors were growing at such high rates because of the conditions existing in this isolated reef. Because Scott reef is so isolated from other reefs and so far offshore, the levels of human influence are reduced. The water quality at Scott reef is much better than other near shore reefs which receive higher levels of pollutants from the coast.

Water quality is linked with the health of reefs and meant that Scott reef had an increased ability to cope with and recover from the bleaching. The reef also received reduced levels of fishing and sedimentation compared to other reefs helping with its surprisingly speedy recovery.

The isolation that was initially considered a hindrance for the reef was actually enabling its survival.

This work proves that coral reefs can spring back from extreme damage. However, this recover is dependent on conditions. These findings are great for those reefs similar to Scott reef; isolated and with reduced human pressure. However, the majority of reefs do not have these qualities and are still at threat from the ever increasing human pressures. Non-isolated reefs are relatively safeguarded by neighbouring reefs sending propagules, but there is only so much these reefs can take.

Even conservative estimations predict that all coral ecosystems could be lost by the end of this century. So although this paper is good news in that it shows another way in which corals can recover after severe damage, the pressures facing coral reefs are ever worsening and need to be addressed.