Our planet.

 

 

 

04 - Coastal and marine waters.

 

Chapter 17 of Agenda 21 stresses the need for the protection of the oceans, all kinds of seas, including enclosed and semi-enclosed seas, and coastal areas, as well as the protection, rational use and development of their living resources. The chapter covers the following programme areas:

* The integrated management and sustainable development of coastal areas, including exclusive economic zones;
* Marine environmental protection;
* The sustainable use and conservation of living marine resources of the high seas;
* The sustainable use and conservation of living marine resources under national jurisdiction;
* The addressing of critical uncertainties for the management of the marine environment and climate change;
* The strengthening of regional and international cooperation and coordination;
* The sustainable development of small islands.

 

A wide variety of human activities can affect the coastal and marine environment. Population pressure, increasing demands for space and resources, and poor economic performances can all undermine the sustainable use of our oceans and coastal areas. The most serious problems affecting the quality and use of these ecosystems are:

* The alteration and destruction of habitats and ecosystems;
* The effects of sewage on human health;
* Widespread and increasing eutrophication;
* The decline of living resources, such as fish stocks;
* Changes in sediment flows due to hydrological changes;
* The impacts of climate change, including rising sea levels (GESAMP, 2001b).

 

Coastal Zone Statistics for Countries Grouped by Region :

 

Source: Burke et al, 2001. Length of Coast (km) Area of Continental Shelf, <200m (1000 km2) Territorial Sea, up to 12 nm for each country (1000 km2) Exclusive Fishing Zone (1000 km2)
North America
398,835
5,107.5
3,484.1
X
Central America & Caribbean
73,703
806.6
1,050.0
197.2
South America
144,567
2,203.0
1,030.0
1,814.1
Europe
325,892
6,316.0
2,589.4
1,783.0
Middle East & North Africa
47,282
786.5
649.7
196.0
Sub Saharan Africa
63,124
987.0
871.9
3,111.1
Asia
288,459
5,515.4
5,730.9
249.5
Oceania
137,772
2,565.0
2,830.4
X
World
1,634,701
24,287.1
18,816.9
12,885.2

 
31. Species Diversity in the World's Seas, 1990 -1998
There is growing evidence that many marine species are less widely distributed, and therefore more vulnerable to extinction, than previously thought. This graphic shows the diversity of marine mammals, sharks, molluscs, birds, and shrimps and lobsters in the world's marine areas.
32. Changes in Marine Species Populations The Marine Species Population Index provides an assessment of the average change over time in the populations of 217 species of marine mammals, birds, reptile, and fish. This graphic shows that between 1970 and 1999, the Marine Species Population Index recorded a decline of about 35%.
33. Global Distribution of Coral, Mangrove and Seagrass Diversity There are two distinct regions in which coral reefs are primarily distributed: the Wider Caribbean (Atlantic Ocean) and the Indo-Pacific (from East Africa and the Red Sea to the Central Pacific Ocean). This graphic illustrates the diversity of corals, mangroves and seagrass in the world's coastal and marine areas.
34. Global Capture Fisheries and Aquaculture Production, 1950 - 1999
This graphic illustrates the levelling off of the global fisheries catch from 1950 to 1999, showing a growing decline in most major fishing areas. It also shows the amounts of aquaculture production in marine water, freshwater and brackish water in 1998.
35. Changes in Catch Ratios of Predatory and Plankton Feeding Fish Indicating Structural Changes in the Marine Ecosystem
Three-quarters of fish stocks are currently exploited to the maximum extent, if not excessively. This graphic illustrates the decline in the catch ratios of predatory and plankton-feeding fish from 1950 to 1995.
36. Benefits from Marine and Coastal Ecosystems and Activities
Besides the well-known economic value of fisheries, there are several other activities generating significant revenues in coastal and marine areas. This graphic discusses the economic benefits of coastal tourism, trade and shipping, offshore oil and gas, and fisheries. It also illustrates the estimated mean value of marine biomes such as estuaries and coastal reefs.
37. Industrial Areas and Seasonal Zones of Oxygen Depleted Waters This graphic illustrates the strong link between areas with high densities of industrial activity and zones of seasonally oxygen depleted waters.
38. Human Actions Leading to Coastal Degradation Physical alteration and destruction of habitats are now considered one of the most important threats to coastal areas. This graphic explains the causes of coastal degradation in estuaries, inter-tidal wetlands and open ocean.
39. Coastal Populations and Shoreline Degradation Coastal Populations and Shoreline Degradation
This graphic shows that the coastal areas with the greatest population densities are also those with the most shoreline degradation.
40. Reefs at Risk: Major Observed Threats to the World's Coral Reefs Major threats to the world's coral reefs include overexploitation and coastal development. This graphic explains which activities or conditions threaten the world's various reefs and shows the global distribution of destroyed coral reefs.
41. What Causes the Sea Level to Change? The global warming that the world is beginning to experience will likely have a major impact on coastal and marine environments. This graphic explains the causes of sea level change and projects the components of mean sea level rise according to Scenario A1F1.
Additional graphics :
A7. Coastlines Under Threat  
A8. The Rising Sea