Natural wetlands are lands which, due to geological or ecological factors, have a natural supply of watereither from tidal flows, flooding rivers, connections with groundwater, or because they are perched above aquifers or potholes.
Realize that many verbs can be both transitive and intransitive. An action verb with a direct object is transitive while an action verb with no direct object is intransitive. Some verbs, such as arrive, go, lie, sneeze, sit, and die, are always intransitive; it is impossible for a direct object to follow.
You might be confusing a gerund after to with the infinitive form of a verb which does require the helping verb to, as in to see, to hear, and to speak. A gerund has no helping verb. When it follows to, the to is a preposition and the gerund, working as a noun, is its object.