The power of nature: ecosystems
An ecosystem is a functional and dynamic unit formed by interdependent living organisms and their environment. In the natural world, mangroves, coral reefs and seagrass beds are juvenile fish nurseries, providing shelter, food and protection from predators. Some fish reside in all three habitats during their lifespan, moving from one to another depending on their species and size. At adulthood, most fish move to deeper or more open zones, but they continue to visit alternate habitats during spawning, tidal and foraging migrations.
Mangrove ecosystems are sediment and nutrient filters encompassing estuarine, arboreal and marine environments. Seagrass rhizomes also trap sedimentation and pollutants and together, these ecosystems create a buffer zone that protects coastal waters from hinterland run-off, efficiently improving water quality and counteracting land-based pollution.
Mangrove’s tolerance to salinity allows them to establish in otherwise barren areas. Their abundant and complex rooting system regulates wave impact, therefore preventing shoreline erosion, and attenuating the impact from severe storms by dissipating the strength of the waves. Seagrass beds tackle currents and waves and stump erosion as well. Moreover, mangrove forest’s peat soil floor and seagrass meadows absorb carbon dioxide. These properties – shore stabilizer, wave breaker and COâ‚‚ sink – demonstrate that mangroves and seagrass beds mitigate climate change.
Consequently, wetlands protect coral reefs from major impacting threats and can damper climate’s drive on other stressors. Inversely, the spatial decline of mangroves due to coastal squeeze might have precipitated the pivotal reduction of herbivores in the Caribbean: up to 40% of herbivore species use mangroves as their juvenile habitat, and several fish species are twice as big when their adult habitat is within a kilometer of mangroves, than their counterparts without such access.