Mangrove restoration is currently not an activity that gets the attention of the community in Kampung Nelayan, Medan Belawan. Even though these activities are very helpful in restoring environmental conditions and coastal biota populations, so that in the long run they can support the welfare and health of coastal communities. Therefore, one of the service activities in the Assisted Village Program is mangrove restoration with the community of Kampung Nelayan, Medan Belawan by paying attention to ecological, social and economic aspects.

Nursery activities that produce good quality seedlings can be a new source of income for the community due to the large number of rehabilitation activities by various parties in the eastern coastal region of North Sumatra, while the availability of seeds is limited. The east coast of North Sumatra has lost about 60% of its mangroves due to various human activities (Onrizal, 2010). So many mangrove seedlings are needed, so the opportunity for mangrove nurseries as a new source of income is very promising.

The purpose of this assisted village service activity is to empower community groups in restoring mangrove ecosystems and increasing the added value of mangrove planting activities through nursery businesses. This activity is useful for restoring mangrove ecosystems in state forest areas, increasing community capacity in mangrove seedling cultivation, and increasing the role of the community in preserving mangrove ecosystems in Kampung Nelayan Seberang Medan.

Rehabilitation of land or former mangrove forest land is very important. The fact of the importance of mangrove ecosystems and the threats facing mangrove forests, makes the need for rehabilitation a must. Actually, mangrove rehabilitation does not always have to be planted because mangroves produce hundreds of thousands of seeds in the form of fruit or seeds per tree every year. With proper hydrological conditions the seeds or fruits can grow on their own, just like where they once grew, thus re-establishing normal hydrology in a short time (Brown, 2006).

Mangrove rehabilitation activities are generally carried out by planting mangrove species Rhizophora sp. The selection of this species in addition to the relatively easy availability of seeds, is also based on the condition of the muddy sand substrate and the high growth ability of this species. Without realizing it, mangrove rehabilitation activities have led to monospecies. This condition, in the short term, can provide benefits to the ecosystem given the faster growth of Rhizopora sp mangroves and their high adaptability to the environment compared to other types of mangroves.

In the long term, it is feared that there will be a reduction in natural mangrove species due to the dominance of one type of plant. Another concern is the vulnerability of rehabilitated mangroves to pest attacks due to the monospecies system. It is recommended to rehabilitators to plant mangroves of various types according to the suitability of the land for planting locations (Fitri and Iswahyudi 2010).