tailieunhanh - Lecture Marine environmental studies - Topic: Ballast water
In the past, ships used solids as ballast; this included metals, sand and rocks. Today, ships use sea water as ballast and it is referred to as ballast water. It is therefore very normal for ships to pump in ballast water at one port and discharge at the loading port before taking cargo. In this chapter you will be able to understand ballast water. | BALLAST WATER Gohoho Emmanuel Sena Ballast Water Necessary to maintain the trim and stability of oceangoing vessels What is Ballast? Ballast is anything used to weight and balance an object. Ships use ballast to maintain balance, stability and structural integrity of the hull. In the past, ships used solids as ballast; this included metals, sand and rocks. Today, ships use sea water as ballast and it is referred to as ballast water. It is therefore very normal for ships to pump in ballast water at one port and discharge at the loading port before taking cargo. 3 Ballast water In the past, ships used solids as ballast; this included metals, sand and rocks. Today, ships use sea water as ballast and it is referred to as ballast water. 4 AQUATIC INVASIVE SPECIES (AIS) 5 Ballast Water and AIS As a result, ships and mariners have unintentionally transferred organisms from one environment to another through the ballast water and sediments Species are introduced with ballast water discharge | BALLAST WATER Gohoho Emmanuel Sena Ballast Water Necessary to maintain the trim and stability of oceangoing vessels What is Ballast? Ballast is anything used to weight and balance an object. Ships use ballast to maintain balance, stability and structural integrity of the hull. In the past, ships used solids as ballast; this included metals, sand and rocks. Today, ships use sea water as ballast and it is referred to as ballast water. It is therefore very normal for ships to pump in ballast water at one port and discharge at the loading port before taking cargo. 3 Ballast water In the past, ships used solids as ballast; this included metals, sand and rocks. Today, ships use sea water as ballast and it is referred to as ballast water. 4 AQUATIC INVASIVE SPECIES (AIS) 5 Ballast Water and AIS As a result, ships and mariners have unintentionally transferred organisms from one environment to another through the ballast water and sediments Species are introduced with ballast water discharge in recipient regions Most of these organisms do not survive, but most of those do die when introduced into the new environment. The few that survive, however, can become very established and can disturb the native ecology 6 What are AIS? Aquatic Invasive Species (AIS) are organisms transported by human activities to a region where they did not occur historically and have established reproducing populations in the wild. Also known as invasive, exotic, alien, introduced, aquatic nuisance species (ANS), nonindigenous species (NIS), non-native Additional Facts Non-native species are considered the second greatest threat to biodiversity after habitat destruction Many non-native species are capable of causing significant ecological, economic or human health impacts In the marine environment, the rate of new introductions has increased exponentially during the last 200 years Example: Overbite Clam Corbula amurensis Detected in SF Bay in 1986 Native to Asia Very high feeding/filtration .
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