Final answer:
The Waddenzee Sea, situated between the intertidal zone and the Frisian Islands, is part of the Netherlands, extending to Germany and Denmark. This area is ecologically important for its tidal flats and wetlands and faces challenges from invasive species like the Pacific oysters. It's also adjacent to the highly significant Rotterdam port.
Step-by-step explanation:
The country that has the Waddenzee Sea, located between the intertidal zone and the Frisian Islands, is the Netherlands. This region is part of Western Europe and lies at approximately 55N latitude and 8E longitude. The Wadden Sea is a unique coastal tidal environment that stretches beyond the Netherlands to encapsulate regions of Germany and Denmark. It is well-known for its ecological significance, including tidal flats, and wetlands, and it serves as a habitat for numerous species, many of which are specifically adapted to the shifting conditions of the intertidal zone.
One of the significant aspects of coastal management in the Netherlands includes the creation of polders, which are areas of land reclaimed from the sea and protected by di-kes, such as the famous Zuider Zee. Additionally, the port city of Rotterdam is noteworthy for its location at the mouth of the Rhine River and for being one of the busiest ports in Europe.
The Wadden Sea has also been experiencing ecological changes due to the introduction of non-native species like the Pacific oysters, which have started to invade mussel beds, affecting the native ecosystems. This illustration of biological invasion has been documented in research and is recognized as a significant environmental issue that affects the biodiversity and function of the Wadden Sea.