Vatan sevgisinden maksat, toprağa değil, onun üstünde yaşayan insanlara duyulan sevgidir.

my thoughts as a learner

duymak = to hear, to sense

duyulmak (passive) = to be heard, to be sensed

duyulan (relative clause) = which was being heard, which was being sensed

duyulan sevgi = the love/affection that was being sensed

duyulan sevgidir = it was the love/affection that was being sensed

The meaning of love for the homeland is not the love for the earth but for the people who live on it.

duymak: feel, sense (also hear).

sevgi duymak, gurur duymak, utanç duymak etc. = feel love/shame/proud.

Ok got it, thanks H & G!