Friday, December 18, 2015

A random wander through recent science: peat, compost, flying, rain in dead forests and coffee

Coffee sparks athletic performance, don’t drain those peat bogs, composting, et cetera.

Today, we’ll take a random walk through some recent science papers. No particular theme, just stuff that caught my attention.


Here’s an interesting, although somewhat misleading piece out of Denmark.

It goes under the headline, “Growing crops on organic soils increases greenhouse gas emissions.” But what it really found is that if you drain a peat bog to make farmland, the peat decomposes and releases higher levels of carbon dioxide than it would if you hadn’t drained the bog.

So, it seems that it’s more the draining of the peat bog than the growing of crops that causes the problem. If you want to stop the carbon dioxide production, just let the water back in: “The climate can be given a helping hand by taking the organic soils out of rotation,” the authors say.


Everybody already knows composting is a better solution than tossing your organic scraps into the trash, right? This new study confirms that, generally, but not always. It is, predictably, published in the journal Compost Science & Utilization.  

The key piece of information is that if you toss food into the trash and it gets landfilled, it produces a lot of methane, which is a powerful greenhouse gas—considerably worse for the climate than carbon dioxide. If you compost, not so much. On the other hand, if a landfill is well managed and the methane is captured for reuse, it can turn the numbers around.

The study uses a couple of measures, including the U.S. EPA Waste Reduction Model (WARM). It concludes, “The WARM model suggests that landfilling yard waste is superior to composting.”

The message, perhaps, is that if your community has a really good landfilling methane recapture system--perhaps making electricity out of it--the landfill is not so bad. Otherwise, compost.


When a forest dies, it makes sense that rainfall will fill streams instead of being sucked up by the trees, right? Nope, according to a study of pine forests killed by the mountain pine beetle

A study in the journal Water Resources Research says that a series of test sites showed that stream flows stayed the same or actually declined in the areas where trees were dying.

The proposed cause was both increased evaporation and increased activity by the understory plants after the death of the canopy trees: 

“Although counter to initial expectations, these results are consistent with increased transpiration by surviving vegetation and the growing body of literature documenting increased snow sublimation and evaporation from the subcanopy following die-off in water-limited, snow-dominated forests.”


A lot of folks talk green, but hardly act green, and air travel is a big example. 

The environmental community may talk a lot about saving the planet, but this has not reduced folks’ flying habits—even though flying is perhaps a human’s most climate-destroying activity.

“Despite the fact that flying can be more damaging than any other activity that an individual can undertake, many otherwise green consumers still choose to fly, offering an opportunity to elicit narratives about the differences between their attitudes and behaviours,” write the authors of this paper, “Flying in the face of environmental concern: why green consumers continue to fly.”

This “do as I say, not as I do” behavior is pervasive, they say.

“There is evidence across a wide range of environmentally responsible behaviours that people advocate specific products or product groups, conservation behaviours and lifestyle choices but that awareness or approval does not necessarily lead to behaviour change.”

What’s clear is that people on the green side do understand the impacts. Some of them try to justify their behavior, suggesting they take more efficient flights, and switch to other form of transportation like trains for shorter trips, but they still travel.

“For the majority of this sample, the ‘doing without’ option was not considered for long-haul flights nor was the possibility of changing travel destinations to accommodate not flying,” the authors said. 

The study was based on interviews with 29 individuals identified as environmentalists.


And finally, on a pretty unrelated subject, some researchers, writing in the International Journal of Sports Nutrition and Exercise Metabolism, found that a cup of coffee before you exercise can improve how you do at it. 

It’s not an actual physical study, but a review of numerous studies done on coffee, other sources of caffeine, and exercise. This won’t be news to a lot of athletes, but it reports that most scientific review of the topic finds that a cup of coffee both increases your performance and also makes you feel like you aren’t working so hard.

“Based on the reviewed studies there is moderate evidence supporting the use of coffee as an ergogenic aid to improve performance in endurance cycling and running,” the authors write

© Jan TenBruggencate 2015

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