The stability mangroves provide is of immense importance. They prevent shoreline erosion by acting as buffers and catch alluvial materials, thus stablizing land elevation by sediment accretion that balances sediment loss. Vital coral reefs and sea grass beds are also protected from damaging siltation. A primary factor of the natural environment that affects mangroves over the long term is sea level and its fluctuations. Other shorter-term factors are air temperature, salinity, ocean currents, storms, shore slope, and soil substrate.
Most mangroves live on muddy soils, but they also grow on sand, peat, and coral rock.
If tidal conditions are optimal, mangroves can flourish far inland, along the upper reaches of coastal estuaries. Mangroves vary in height according to species and environment, from mere shrubs to 40 meter trees. The lenticels are inactive during high tide. Evolutionary adjustments to varying coastal marine environments have produced some astounding biological characteristics within mangrove plant communities. Certain species of mangroves exclude salt from their systems, others actually excrete the salt they take in via their leaves, roots, or branches.