“A connection between to individuals in a network. In the case of seed exchange, links are materialized by the movement of seed between individuals”

Outgoing link: “Link directed out of an individual. In the case of seed exchange, an outgoing link implies that seed was given by the individual”
Incoming link: “Link directed into an individual. In the case of seed exchange, an incoming link implies that seed was received by the individual”

References

Pautasso, M. (2015). Network simulations to study seed exchange for agrobiodiversity conservation. Agron. Sustain. Dev. 35, 145–150. https://doi.org/10.1007/s13593-014-0222-9