I think exportador and importador might refer to runoff and run-on.

Run-on is an important process in the hydrological and ecohydrological behaviour of semi-arid ecosystems. Tiger bush is an example of a vegetation community that develops a patterned structure in response to, in part, the generation of runoff and run-on.

https://en.wikipedia.org/wiki/Run-on

Se identificaron 3 tipos de dinámicas hidrológicas en las laderas restauradas, que tienen que ver con el volumen de escorrentía superficial circulante por ellas como consecuencia de la entrada externa de escorrentía (runon) procedente de la cabecera.

Ladera con volumen intermedio de escorrentía con geoformas exportadoras e importadoras

http://zonanosaturada.com/jornadas-zns-2017/salida-de-campo/

In such conditions, soil water storage is very low because runoff exceeds run-on and lichens can out-compete annual plants.

https://books.google.es/books?id=qjHoYZXQee0C&pg=PA316&lpg=P...

I've seen indented landscapes, though that's not quite the same as 'formas de relieve'.

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Note added at 9 hrs (2017-11-11 20:10:42 GMT)
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Similarly, beaver dams can alter the flow regime of streams, potentially buffering flood waves and altering valley morphology, which in turn influences flood hydraulics and possibly riparian vegetation. This raises some interesting questions: can beavers “heal” channels that have been artificially straightened Could the introduction of beavers essentially “capture” a significant fraction of spring runoff in valleys, releasing it slowly and thereby partly compensating for earlier snow melt? Is there a threshold crossed such that when a channel is straightened, beavers are no longer able to thrive – either because a straightened channel affords few potential dam sites, or because of loss of riparian forest due to water-table lowering, or both?

http://csdms.colorado.edu/w/images/CTWG_meeting_report_oct09...