De or het auto-ecologie?

The correct Dutch article is:

de auto-ecologie

Rule Words ending in -logie: always de. See the rule
Meaning (Dutch) (biologie) de studie van de ecologie van een individuele plant of soort

How to use auto-ecologie

the auto-ecologiede auto-ecologie
this auto-ecologiedeze auto-ecologie
that auto-ecologiedie auto-ecologie
our auto-ecologieonze auto-ecologie
your auto-ecologiejouw auto-ecologie
every auto-ecologieelke auto-ecologie
which auto-ecologie?welke auto-ecologie?
a big auto-ecologie / the big auto-ecologieeen grote auto-ecologie, de grote auto-ecologie

Meaning, plural, diminutive, pronunciation and translations: WikiWoordenboek (Dutch Wiktionary) (CC BY-SA 4.0). Example sentences: Tatoeba (CC BY 2.0 FR).