The thermophilous oak forests seem to occupy the niche between acidophilous and mesophilous forest.
Tomasz H. Szymura, Magdalena Szymura 2013, 'Spatial variability more influential than soil pH and land relief on thermophilousvegetation in overgrown coppice oak forests', Acta Societatis Botanicorum Poloniaehttps://pbsociety.org.pl/journals/index.php/asbp/article/view/413. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
Species which constitute this functional group are mainly acidophilous.
M. Negadi, A. Hassani, M. Ait Hammou, W. Dahmani, M. D. Miara, M. Kharitonov, O. Zhukov 2018, 'Diversity of Diatom epilithons and quality of water from the subbasin of Oued Mina(district of Tiaret, Algeria)', Ukrainian Journal of Ecologyhttp://ojs.mdpu.org.ua/index.php/biol/article/view/2151. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
On the other hand, the share of fresh soils indicators and acidophilous species significantly decreased.
Pilková Ivana 2014, 'Changes of the Ecological Conditions in the Báb Forest on the Basis of a BioindicationMethod', Ekológia (Bratislava)http://www.degruyter.com/view/j/eko.2014.33.issue-3/eko-2014-0020/eko-2014-0020.xml?format=INT. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
They are acidophilous species, so the acidification of the environment probably promotes their expansion.
Ewa Fudali, Mirosław Szczepański, Anna Rusińska, Stanisław Rosadziński, Grzegorz Wolski 2011, 'The current distribution in Poland of some European neophytic bryophytes with supposedinvasive tendencies', Acta Societatis Botanicorum Poloniaehttps://pbsociety.org.pl/journals/index.php/asbp/article/view/374. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)