Unlikely the biodiversity crisis will improve any time soon

6 02 2020

hopelessAround a fortnight ago I wrote a hastily penned post about the precarious state of biodiversity — it turned out to be one of the most-read posts in ConservationBytes‘ history (nearly 22,000 views in less than two weeks).

Now, let’s examine whether this dreadful history is likely to get any better any time soon.

Even if extinction rates decline substantially over the next century, I argue that we are committed to an intensifying biodiversity extinction crisis. The aggregate footprint from the growing human population notwithstanding, we can expect decades, if not centuries, of continued extinctions from lag effects alone (extinction debts arising from previous environmental damage engendering extinctions in the future)1.

Global vegetation cover and production are also likely to decline even in the absence of continued habitat clearing — the potential benefit of higher CO2 concentrations for plant photosynthesis is more than offset by lower availability of water in the soil, heat stress, and the frequency of disturbances such as droughts2. Higher frequencies and intensities of disturbance events like catastrophic bushfire will also exacerbate extinction rates3.

However, perhaps the least-appreciated element of potential extinctions arising from climate change is that they are vastly underestimated when only considering a species’ thermal tolerance4. In fact, climate disruption-driven extinction rates could be up to ten times higher than currently predicted4 when extinction cascades are taken into account5. Read the rest of this entry »





Increasing human population density drives environmental degradation in Africa

26 06 2019

 

stumps

Almost a decade ago, I (co-) wrote a paper examining the socio-economic correlates of gross, national-scale indices of environmental performance among the world’s nations. It turned out to be rather popular, and has so far garnered over 180 citations and been cited in three major policy documents.

In addition to the more pedestrian ranking itself, we also tested which of three main socio-economic indicators best explained variation in the environmental rank — a country’s gross ‘wealth’ indicator (gross national income) turned out to explain the most, and there was no evidence to support a non-linear relationship between environmental performance and per capita wealth (the so-called environmental Kuznets curve).

Well, that was then, and this is now. Something that always bothered me about that bit of research was that in some respects, it probably unfairly disadvantaged certain countries that were in more recent phases of the ‘development’ pathway, such that environmental damage long since done in major development pulses many decades or even centuries prior to today (e.g., in much of Europe) probably meant that certain countries got a bit of an unfair advantage. In fact, the more recently developed nations probably copped a lower ranking simply because their damage was fresher

While I defend the overall conclusions of that paper, my intentions have always been since then to improve on the approach. That desire finally got the better of me, and so I (some might say unwisely) decided to focus on a particular region of the planet where some of the biggest biodiversity crunches will happen over the next few decades — Africa.

Africa is an important region to re-examine these national-scale relationships for many reasons. The first is that it’s really the only place left on the planet where there’s a semi-intact megafauna assemblage. Yes, the great Late Pleistocene megafauna extinction event did hit Africa too, but compared to all other continents, it got through that period relatively unscathed. So now we (still) have elephants, rhinos, giraffes, hippos, etc. It’s a pretty bloody special place from that perspective alone.

P1080625

Elephants in the Kruger National Park, South Africa (photo: CJA Bradshaw)

Then there’s the sheer size of the continent. Unfortunately, most mercator projections of the Earth show a rather quaint continent nuzzled comfortably in the middle of the map, when in reality, it’s a real whopper. If you don’t believe me, go to truesize.com and drag any country of interest over the African continent (it turns out that its can more or less fit all of China, Australia, USA, and India within its greater borders).

Third, most countries in Africa (barring a few rare exceptions), are still in the so-called ‘development’ phase, although some are much farther along the economic road than others. For this reason, an African nation-to-nation comparison is probably a lot fairer than comparing, say, Bolivia to Germany, or Mongolia to Canada.

Read the rest of this entry »





The economy worse off since 1978

3 07 2013
eat money

Can’t eat money

I was only a little tacker in 1978, and as any little tacker, I was blissfully unaware that I had just lived through a world-changing event. Just like that blissfully ignorant child, most people have no idea how important that year was.

It was around that year that humanity exceeded the planet’s capacity to sustain itself in perpetuity1. As I’ve just discovered today, it was also the same year that the per-capita Genuine Progress Indicator (GPI) peaked.

Now for a little detour and disclaimer before I explain all that. I’m not an economist, but I have a dabbled with the odd economic concept and bolted-on economic sub-routine in a few models I’ve written. Some would argue that conservation (i.e., the quest and methods needed to conserve biowealth) is almost entirely an economic pursuit, for economics is the discipline that attempts to explain (and modify) human behaviour. I tend to agree insofar as we now know enough on the biological side regarding how species become threatened and go extinct, and what kind of things we need to do to avoid losing more of the life-support system provided by biodiversity. Being completely practical about it, one could even argue that the biology part of conservation biology is complete – we should all now re-train as economists. While that notion probably represents a little hyperbole, it does demonstrate that economics is an essential endeavour in the fight to conserve our home.

Almost everyone has heard of ‘GDP’ – the Gross Domestic Product – as an indicator of economic ‘performance’, although most people have little idea what it actually measures (I’m including businesspeople and politicians here). GDP is merely the sum of marketed economic activity, which is only one small facet of the economy. For example, growing a tomato and preparing a salad for your family with it is not included, yet buying a frozen meal in the supermarket is. Even an oil spill increases GDP via increased expenditures associated with clean-up and remediation, when clearly it is not a ‘good’ thing for the economy on the whole because of the lost opportunities it causes in other sectors. Read the rest of this entry »