Biotic factors are anything in a ecosystem that is living, was living, or is going to live.
From this we can conclude that the biotic factors are remains of dead organisms and flora and fauna.
Temperature and minerals in the soil are abiotic, meaning they will never live.
This can affect the organisms living there because now, their environment is probably different than what they have been living in for a long time, so now they have to adapt to this new environment, and if they don't, the organisms will probably end up dying.
The x-axis shows the relative
amount of DNA per cell thought not directly. This can be seen through a
histogram a specific type of a graph. Looking at the bars of the histogram you
can follow peaks and dips which correspond to something like fluorescence which
indirectly shows the relative amount of DNA in cell.