Mangroves Response to Climate Change: A Review of Recent Findings on Mangrove Extension and Distribution

Abstract

Mangroves function as a natural coastline protection for erosion and inundation, providing important environmental services. Due to their geographical distribution at the continent-ocean interface, the mangrove habitat may suffer heavy impacts from global climate change, maximized by local human activities occurring in a given coastal region. This review analyzed the literature published over the last 25 years, on the documented response of mangroves to environmental change caused by global climate change, taking into consideration 104 case studies and predictive modeling, worldwide. Most studies appeared after the year 2000, as a response to the 1997 IPCC report. Although many reports showed that the world's mangrove area is decreasing due to direct anthropogenic pressure, several others, however, showed that in a variety of habitats mangroves are expanding as a response to global climate change. Worldwide, pole ward migration is extending the latitudinal limits of mangroves due to warmer winters and decreasing the frequency of extreme low temperatures, whereas in low-lying coastal plains, mangroves are migrating landward due to sea level rise, as demonstrated for the NE Brazilian coast. Taking into consideration climate change alone, mangroves in most areas will display a positive response. In some areas however, such as low-lying oceanic islands, such as in the Pacific and the Caribbean, and constrained coastlines, such as the SE Brazilian coast, mangroves will most probably not survive.

Novel Indicators of Anthropogenic Influence on Marine and Coastal Ecosystems

“…Additionally, identifying areas that currently have high PPI or RPI is useful for risk analyses associated with future human population expansion interacting with biogenic habitats. For example, mangrove forests are experiencing range expansion to higher latitudes in some regions due to global warming (Cavanaugh et al, 2014;Godoy and Lacerda, 2015). Given the "blue carbon" potential of mangroves, this could result in increased sequestration of organic carbon to offset global CO 2 emissions.…”

Wetlands In a Changing Climate: Science, Policy and Management

“…In fact, globally, mangroves are expanding their range from tropical and subtropical climes, to invade salt marshes on adjacent warm temperate coasts (e.g. Godoy and DeLacerda 2015). Studies are finding that climate-changed-induced movement of mangroves into saltmarsh with warming temperatures is resulting in increases in the carbon stored in biomass and soils in marine and estuarine mangroves.…”

Systematic Planning and Ecosystem-Based Management as Strategies to Reconcile Mangrove Conservation with Resource Use

“…While not being the main focus of most discussions about the new law, the changes on the legal framework for mangrove protection did not go unnoticed: an important sub-system, the "apicum" {escape valve for inland migration of mangroves as an adaptive response to sea level rise (Godoy and Lacerda, 2015)}, was removed from the concept of mangrove ecosystem, being now separately attended to by this new law in a less strict level of protection. These salt flats are non-vegetated areas, essential for the maintenance of the forested area in the mangrove systems (Schmidt et al, 2013) and are the ecosystem's last resource in terms of space to persist transitional periods and sea level rise (Oliveira-Filho et al, 2016).…”

“…Such a division is based on Knoppers et al (1999) and Godoy and Lacerda (2015), as well as on the approaches mentioned in the previous paragraphs (Figure 1).…”

“…A steep coastline in the southeast and semiarid conditions in the northeast limit a possible landward refuge of forests facing sea level increase, hence restricting them to a narrow fringe along these coasts (Ferreira and Lacerda, 2016a). These traits, summed up with strong human-use pressures (Godoy and Lacerda, 2015), might hinder mangrove survival in the face of climate change. On the other hand, mangrove areas have the chance to expand in the northern part of the coastline, following predictions related to sea-level rise, because here mangroves find landward areas for expansion, such as in the Amazon estuary (Cohen and Lara, 2003;Cohen et al, 2008;Ward et al, 2016).…”