According to a 2013 Daily Mail article :
greater evaporation and chemical reactions with rainwater will take away more and more carbon dioxide.
In less than a billion years, its levels will be too low for photosynthesising plants to survive, say scientists. When that happens, life as we know it on Earth will cease to exist.
A more scientific version of this is Swansong Biospheres: Refuges for life and novel microbial biospheres on terrestrial planets near the end of their habitable lifetimes International Journal of Astrobiology.
This article says:
Increased Temperatures --->
Increased weathering of silicate rock --->
Carbon drawdown --->
Plate tectonics slows --->
Carbon recycling slows --->
Pant life unsustainable <10 ppm CO2
~0.9 Gyr
As background see Carbonate–silicate cycle. Carbon Dioxide is removed from the atmosphere by the chemical reaction:
CaSiO3(s) + 2CO2(g) + H2O(l) → Ca2+(aq) + 2HCO3-(aq) + SiO2
Is this really accepted science, that plant-life on Earth will end, due to too little CO2, in less than one billion years?