From: Assessing the relevance of atmospheric heavy metal deposition with regard to ecosystem integrity and human health in Germany
pH classes original from BÃœK1000N
pH(CaCl2) of
pH(CaCl2) to
pH(CaCl2) middle
a0/s0
6.8
7.2
7
a1
7.9
7.6
s1
6.1
6.4
s2
5.4
5.8
s3
4.7
5.0
s4
4
4.4
s5
3.3
3.6