Decay

The natural decomposition of fallen leaves takes up to a year but the process can be accelerated with the help of ants, worms  fungi and other microbes as well as by atmospheric conditions, temperature, precipitation etc. A team of scientists from MIT dug leaf litter in porous bags in 27 locations of  Central and North America for then to redig them up every year for 10 years, to weigh and analyse the litter. We all have different ways to have fun don't we! They then created a mathematical model that showed that the two most important factors for leaf decay was indeed the climate and the composition of the litter. I don't think that really came as a surprise!
But the scope of the study wasn't just that straightforward (they rarely are), for as leaf decay generates carbon dioxide, and (I quote) "as temperatures rise, decomposition will likely speed up, releasing more carbon dioxide into the atmosphere, which in turn creates warmer temperatures, further speeding decay in a positive feedback loop."  What!

I have done my own little study, on the stairway of St. Alessandro on my daily lunchwalk to the old city. The first photo was taken 4 weeks ago,the second 2 weeks ago and the last one today. Apart from the fact that I'm appalled by the quality of the photos (taken on my phone) and the fact the stairways very rarely get cleaned, it shows the first month of the natural decay process of fallen leaves. 

P.s.
This is backbliped as I erroneously cancelled a fullwritten entry yesterday and then didn't have time to rewrite  it due to marathon-watching of the last episodes of Casa del Papel (Moneyheist)!