Résumé
By definition ‘ecosystem engineers’ are those organisms capable to modify physically the environment by producing ‘biogenic’ structures (BS). Large macroinvertebrates like termites, earthworms and ants produce BS with distinguishable physico-chemical properties. We measured total C
org,
NH
4
+
and
NO
3
−
contents in the BS produced by two species of Neotropical termites (subfamily Nasutermitinae) in a gallery forest (GF) of the Eastern Plains of Colombia. We sampled from the top of the BS to the edge at proportional distances, i.e. 20–100% for the largest BS in the soil surface and 50–100% for the smallest arboricole BS. Control soil was sampled 1
m apart from the BS. Values of total C
org were high in the BS produced by
Nasutitermes sp1 (epigeic mound), while a high N mineralization process was observed in the same BS and in the
Nasutitermes sp2 arboreal nest. The role of these two ecosystem engineers in nutrient cycling is discussed.