Anthropogenic, Direct Pressures on Coastal Wetlands

Abstract

Coastal wetlands, such as saltmarshes and mangroves that fringe transitional waters, deliver important ecosystem services that support human development. Coastal wetlands are complex social-ecological systems that occur at all latitudes, from polar regions to the tropics. This overview covers wetlands in five continents. The wetlands are of varying size, catchment size, human population and stages of economic development. Economic sectors and activities in and around the coastal wetlands and their catchments exert multiple, direct pressures. These pressures affect the state of the wetland environment, ecology and valuable ecosystem services. All the coastal wetlands were found to be affected in some ways, irrespective of the conservation status. The main economic sectors were agriculture, animal rearing including aquaculture, fisheries, tourism, urbanization, shipping, industrial development and mining. Specific human activities include land reclamation, damming, draining and water extraction, construction of ponds for aquaculture and salt extraction, construction of ports and marinas, dredging, discharge of effluents from urban and industrial areas and logging, in the case of mangroves, subsistence hunting and oil and gas extraction. The main pressures were loss of wetland habitat, changes in connectivity affecting hydrology and sedimentology, as well as contamination and pollution. These pressures lead to changes in environmental state, such as erosion, subsidence and hypoxia that threaten the sustainability of the wetlands. There are also changes in the state of the ecology, such as loss of saltmarsh plants and seagrasses, and mangrove trees, in tropical wetlands. Changes in the structure and function of the wetland ecosystems affect ecosystem

The Case for a Critical Zone Science Approach to Research on Estuarine and Coastal Wetlands in the Anthropocene

“…In the age of burgeoning anthropogenic disruption that has arguably seen the dawn of a new geological epoch-the Anthropocene-global environmental change has wrought impacts of increasing frequency and magnitude. Estuarine and coastal ecosystems are among the most vulnerable of all natural systems in which the full range of physical, chemical and biological processes are threatened by anthropogenic forces (Newton et al 2020). For more than 7000 years, humans have '…profoundly impacted, degraded or destroyed…coastal wetlands' (Hopkinson et al 2019, p. 37) both directly and indirectly.…”

“…It is clear, therefore, that coastal wetlands buffer sea level rise and climate change and are important controlling elements in a wide range of physical and biogeochemical processes (Newton et al 2020). Barbier (2019: 958) notes, however, that '…there is still skepticism among wetland regulators and coastal managers about how useful such valuation studies are'.…”

Contribution of Remote Sensing Technologies to a Holistic Coastal and Marine Environmental Management Framework: A Review

“…While DAPSI(W)R(M) is increasingly used as a holistic framework for integrated coastal and marine management [4,[31][32][33][34][35][36], there has only been limited use of RS technologies to support this management framework. For instance, [37] addressed satellite and airborne remote sensing for supporting Marine Spatial Planning (MSP) and Integrated Coastal Area Management (ICAM) by providing a list of relevant sensors.…”

“…The increasing influence of human activities on the coast and the ocean leads to a variety of anthropogenic pressures combined with natural pressures, which make them hotspots of global change [36,175]. Recent advances in remote sensing technologies (RS) can help in mapping and assessing the pressures.…”

“…Coastal wetlands play an important role in protecting communities from climate change impacts, as they moderate the climate and at the same time, are vulnerable ecosystems [36,247]. RS applications provide knowledge to understand the functioning process of these ecosystems.…”