This is a listing of my top 10 environmental research of the year. I don’t follow energy or sustainability research, so don’t expect anything on those; only climate change and its effects, and whatever else humans are doing to screw around with the planet and other species. The master list contains 19 paper. [OA] indicates open access papers.
The single greatest danger to biodiversity isn’t climate change, it’s habitat loss and the resulting reduction in ecosystem complexity. This paper underlines this by finding that in the long term, species richness in an ecosystem compounds its productivity, meaning that losing even a couple of species that may appear redundant will be damaging.
As the graphs above show, this paper finds that phytoplankton abundances have experienced a sudden statistically significant decrease since ~2005 in the Carribean, as measured by the CARIACO coastal station off the coast of Venezuela. This is linked to changes in hydrological and circulation cycles (specifically the ITCZ and the Azores High) caused by global warming: they lead to less upwelling, warmer water at the surface, and more stratification, which overall leads to less nutrients, and thus less productivity.
The result of this study is summed up in B above: a halving of the living coral cover in the Great Barrier Reef from 28% to 13.8% from 1985 to today. If that’s not cause enough for concern, realise that the GBR is one of the most protected marine localities, and it’s a World Heritage Site. Despite that, it’s getting devastated (no need to mince words). The reason for the coral deaths here are increased bleaching (driven by higher temperatures), lower water quality (global warming leading to increased precipitation, leading to more run-off into the ocean), and lower growth rates (warming leads to thermal stress). Corals are some of the most sensitive organisms living today, and this paper just gives us a glimpse of what the marine future will be like.
In the diagram above, the orange Ds indicate when blue whales did D calls, characteristic low-frequency calls they make when foraging. In the presence of ship sonar, the calls stop. When ships are around, D calling increases, most likely to overome the sounds made by the ship (similar to how urban birds sing more loudly than their rural counterparts). What the functional effects of these influences are still need to be researched, and probably will be soon given that blue whales are endangered.
Oh dear, oh dear, caesium levels in the ocean rose 1000 times in the aftermath of Fukushima! That sounds like a big number, until you realise that they’re still less than naturally occurring radionuclides, like polonium. Think about this next time you want to use Fukushima as an example of a nuclear disaster.
I may sound like a bitter alarmist when speaking about climate change, but I also like to remind people that climate changes happen all the time, and while this one is drastic, there will alwways be some organisms who will profit (it just so happens that humans will not be one of them, for better or for worse). This paper finds that sea anemones might be one of those who profit: ocean acidification appears to enhance their productivity and growth. They don’t have a calcified shell to worry about maintaining, hence their getting a leg up over calcifying corals and molluscs.
This is an example of experimental evolution done well. Lohbeck et al. took Emiliania huxleyi, one of the most dominant coccolithophores, and let it evolve for 500 generations through serial transfers to increasingly more CO2-enriched water. They show that instead of dying out, they gradually adapted, increasing their growth in the higher acidic conditions by the end of the experiment. It’s only a lab experiment though, so it just shows that the possibility to adapt is there; whether this will occur in the rough-and-tumble of the wild cannot be guaranteed.
In #5, I made a distinction for calcified organisms being more affected by ocean acidification because of their shells. This paper gives the starkest example of this using pteropods: in the pictures above, a and b are regular shells; c and d are under slight acidification; e and f are at high acidification, and the shell is extremely deteriorated because of its dissolution – and these are from the wild (the paper also has experimental analyses to determine at what level they dissolve). There is no need to stress how damaging this is to pteropods, and similar effects are observed in all calcium carbonate-shelled organisms.
Ocean acidification induces budding in larval sea urchins is a relevant paper that shows a negative response by sea urchins to ocean acidification: larval budding, leading to unviable clones.
Climate change will affect plants by reducing their range and by reducing their genetic diversity. This paper estimates just how much genetic diversity will be lost in 27 alpine and arctic species by 2080, under a range of climate models. It’s a lot, although it does vary by species and model, and most of these plant species will fall into the endangered category if the IUCN starts taking genetic diversity into account (which they probably will at some point). So, bad news.
I am making an exception and adding a review paper, because this one really is excellent and thorough, and a great placeholder until the new IPCC report comes out. If you need up-to-date data on CO2 emissions from fossil fuels, and details on how those numbers are compiled and calculated, this is exactly the paper you want.