92 12.11 Protecting the Marine Environment

Focus on Coral Reefs

Coral reefs (or coral ecosystems) are among the most important and also most sensitive habitats throughout the world’s oceans. Reefs provide habitat, spawning and nursery grounds for economically important fish species, and are hotspots of marine biodiversity. For humanity, coral reefs provide billions of dollars in economic and environmental benefits, including fishing, coastal protection, recreation, and tourism. Hundreds of millions of people worldwide depend of reef ecosystems for their livelihoods and food. However, coral ecosystems face serious threats from unsustainable fishing and land-based pollution (Figures 17-30 and 17-31).

Unfortunately, many of the world’s reefs have already been destroyed or severely damaged by pollution, unsustainable fishing practices, disease, introduction of invasive species, ship groundings, uncontrolled coastal development and other impacts.

Human activities are a primary cause for reef destruction. Pollutants from expanding coastal communities find their way to shallow coastal waters dominated by coral reefs, mostly in warm tropical waters. Many of the sea creatures, particularly invertebrates that attach to the seabed and filter seawater. Tourist visiting reefs step on fragile reef structures, introduce chemicals (such as zinc and other compounds in sun screen). Sewage and urban runoff carries silt (increasing turbidity) and introduce toxins that impact or kill reef organisms. Perhaps most alarming are the impacts of changes in water temperature and water chemistry associated with climate change.

Climate Change – The most important environmental issue of our times!

Studies conducted throughout the world’s oceans show the coral ecosystems are showing the detrimental effects of climate change caused by the burning of fossil fuels, deforestation, and bad agricultural practices that release large quantities of greenhouse gases into the atmosphere.

Climate change impacts coral ecosystems by increasing sea-surface temperatures and increased carbon dioxide levels in seawater. Long-term studies of CO₂ concentrations in seawater show trends in reducing calcification rates in reef-building and reef-associated organisms. Increased sea surface temperature leads to coral bleaching (a result in the loss of symbiotic algae and bacteria) and death of skeletal reef-building organism. Weakened coral communities are susceptible to infection disease. Pollution from coastal development and agricultural runoff can also impede coral growth and reproduction, disrupt ecological functions, and cause disease.

Coal is the most carbon-intensive fossil fuel, producing the most carbon dioxide per unit volume burned. For every ton of coal burned, approximately 2.5 tons of CO₂ is released into the air. Globally, coal is the largest-used fossil fuel source and the highest production of carbon dioxide emissions. Although coal represents only about one-third of share of fossil fuels consumed by the world’s total primary energy supply, coal is responsible for 43% of carbon dioxide emissions from burning fossil fuels.

Politics of Climate Change: Sadly, our world may be in big trouble because of the economics associated with energy and agricultural demands of a growing world population. Failure to address carbon emissions and the resultant impacts of rising temperatures and ocean acidification could make many marine and coastal management efforts futile. While reducing CO₂ and other greenhouse gas emissions is vital to stabilize the global climate is essential, the excess that already exists in the atmosphere will persist throughout the next century.

Climate changes will have many impacts on marine systems including reduction in marine biodiversity, sea level is rising, and long-term forecasts predict changes in the frequency, intensity, and distribution of tropical storms as atmospheric and ocean circulation patterns change.

Politics vs. Technology: The key to saving or destroying our natural environments

The climate change issues will be every-increasingly important as the impacts become increasingly obvious as the number of natural and man-made disasters steadily rises. Humans have to collectively choose, through political means, to make the choices to change to cleaner technologies, and protecting and managing resources. The choices to move away from fossil-fuel consumption to alternative energy sources will be expensive and a hard fight because it will impact the livelihoods of many people (such as coal miners and workers in the petroleum industries). Predicted sea-level rise and global warming will impact all world’s communities, both human and ecosystems. There will be many winners and losers in the transition to a cleaner, more sustainable world. Accepting the consequences for climate change will create many new jobs in the process. The longer humanity waits to make these changes, the greater the environmental problems will be in the future. “We can’t fool mother nature!”