Marine environments are extremely harsh on metals. The presence of ions such as chlorides and ozone create an ideal environment for chemical attack. Combined with the physical attack of wave action, erosion and microbial attack, metals have a hard time.
Sea water, if not destructive enough on its own, has several powerful allies assisting the breakdown of metals and non metals alike. Living allies in sea water also enhance its destructive power. Microbiological organisms, weeds and limpets as well as deposits of sand, silt or slime not only exclude oxygen but often create locally corrosive conditions under these deposits which aggravate attack. Coatings and composite structures can experience rapid degradation. Sulphate reducing bacteria, left undisturbed in marine silt or mud deposits, will produce concentrations of hydrogen sulphide which are particularly aggressive to steel and copper based alloys.
Corrosion of Buried Metal Work
Soil conditions can vary enormously. Here water is held in a great complexity of ways and contains a wide variety of corrosive ingredients. (Menzies, et al., 1965). When coupled with bimetallic effects, materials may rapidly succumb to corrosion within these environments.
Industrial / Chemical effects
Certain environments in the chemical industry can lead to other forms of corrosion; most notably high temperatures, abrasion and the presence of substances such as sulphur and hydrogen.
See here for examples of issues of sulphur corrosion on copper conductors.
For information on the role of temperature, chlorine, and organic matter, click here.
The effects of ammonia are discussed here.