Definition: The term "polder" comes from Dutch, which means "pool" or "pond." It is a type of artificial wetland that is typically built upon a river or other waterbody to provide habitat for aquatic plants, animals, and even humans who may have used it in the past. Polders are often formed by rivers or streams and can vary in size depending on their location. They may be shallow and only slightly deeper than the surface of the water they float on, allowing for a variety of aquatic life to thrive. Polders can also be found on islands or rocky shores, where they provide shelter from the elements while offering a source of freshwater. Some common types of polder include:
Blackwater Polder: A shallow, deeper pool built by rivers in areas with very low soil quality, which often leads to waterlogging and poor aquatic conditions. The vegetation is usually dominated by submerged aquatic plants like orchids, sea anemones, and coral.
White Water Polder: Another form of polder, this one has a deeper depth than the blackwater polder, but still offers some shelter from the elements. It is often found in areas where river runoff has carried sediment down into the waterway for long periods of time.
Blackwater and Whitewater Polder: Similar to the white water polder, these two types of polders are both shallow and have a deeper depth than the blackwater or white water polder. They can be found in areas with high soil quality but low waterlogging.
Salt Water Polder: This type of polder is similar to a blackwater polder, but it is filled primarily by freshwater runoff from the surface of bodies of saltwater rather than water. It can provide shelter and habitat for aquatic life but may also lead to a greater risk of salt intrusion into the waterway. Overall, polders are an important feature of many wetlands ecosystems, providing habitat for a wide range of plants, animals, and humans who have used them in the past.

Polder