Calculate in teragrams the difference in the supply of phosphorus to the soil from the two stores shown in Figure 1 - AQA - A-Level Biology - Question 3 - 2023 - Paper 2

Next, we find the supply of phosphorus to the soil:

For the biotic component, the phosphorus that decomposes contributes 0.05%:

$Phosphorus_{soil, biotic} = 0.05\\times (2.1 imes 10^3 Tg) = 1.05 imes 10^{1} Tg$

From the rocks, the contribution, based on weathers and erosion, is:

$Phosphorus_{soil, rocks} = 1.3 imes 10^{-10} imes (1 imes 10^{13} Tg) = 1.3 imes 10^{3} Tg$

Finally, we find the difference in supply of phosphorus to the soil from the two stores:

$Difference = Phosphorus_{soil, rocks} - Phosphorus_{soil, biotic}$

$Difference = 1.3 imes 10^{3} Tg - 1.05 imes 10^{1} Tg \approx 1.299 imes 10^{3} Tg$

Thus, the difference is approximately 1298 Tg.