Delta vs. Estuary Game Quiz Online

This page features a Delta vs. Estuary Game Quiz Online. It is an exercise for students studying science in 3rd, 4th, 5th, 6th to 8th grades. Students will learn about deltas and estuaries in this online activity. Remember to learn more by readding the article below.

 

Delta and Estuary and Its Impact on Birds

There are many fascinating things to know about a Delta and Estuary, and this article will help you understand its nature and structure. It will also discuss the geology and the impact of deltas on birds.
Nature of deltas
The physical properties of estuaries and deltas are complex and dynamic ecosystems, with a wide variety of interactions. The resulting delta morphology is dependent on several factors, including the general wave climate, discharge dynamics, tidal regime, sedimentary and biotic characteristics. This article summarizes key physical features of estuaries and deltas, and suggests how these factors interact to shape the landscapes they support.
Most deltas have silt-rich sediment deposits and are fertile agricultural areas. The Ganges-Brahmaputra delta in India, which empties into the Bay of Bengal, is the largest delta in the world, and Bangladesh is located entirely on its shores. Deltas are highly productive agricultural areas, with the primary products being rice and fish. The Sacramento and San Joaquin rivers in California are among the richest agricultural areas in the United States. The soil is perfect for growing crops like wine grapes, asparagus, and zucchini.
A river delta is formed when a river enters a body of water and sediment settles on the surface. As the river flows into the standing water, it expands, reducing the velocity of its flow. This results in sediment settling at the bottom of the river, which is then deposited as alluvium. Often, this buildup pushes the mouth of the river into the delta.
Geology of deltas
The origin of deltas is unknown, but they are usually located on the trailing edges of passive or active margins. Three factors determine the formation of deltas: topography, tidal forces, and river discharge. The last factor has the largest impact on delta shape. The following sections detail the origins of deltas and estuaries. They are important in understanding how deltas form. 
The Ebro delta is an example of a wave-dominated river delta where tidal motion is almost non-existent. In millennia past, the Ebro delta had high sediment discharge, but this was reduced to one million tons per year after 1950. The river discharge decreased from 600 m3/s to 400 m3/s, while the peak discharge dropped to three times the average discharge. This reduced fluvial discharge had significant impacts on delta morphology.
While a delta is a river-like body of saline water, an estuary is a semi-enclosed body of water with free access to the sea. Both are associated with a river and an ocean, and represent a transitional zone between two aquatic environments. 
Impacts of depleting deltas on birds
The global population is increasing at a rate of 2% per year, with significant regional variation. Hence, deltas have huge environmental values and major economic potential, and the balance between economic development and ecological stewardship is crucial to their continued viability. The Aquaterra Conference will address some of these issues, focusing on eight strategically selected deltas in economically and densely populated regions. 
Water is a key factor in maintaining the health of Deltas and estuaries. Increasing water levels in a Delta will eventually cause more salty water to enter Bays, flooding islands. This will require massive levees, which will be extremely expensive. Therefore, the government is encouraging cities to reduce their dependence on Delta water. However, many people remain concerned about the long-term effects of the depletion of Deltas.
In addition to serving as critical stepping stones for migrating birds, deltas also serve as strategic positions along flyways. In fact, the Delta has been officially designated a Ramsar Site, which means it has high international significance in terms of bird populations. These three sites include the Volga, Danube, and Ebro deltas. The Ebro delta, for example, has undergone massive reductions of coastal wetlands in recent years. It is therefore important for governments to be actively involved in solving the problems associated with the depletion of deltas.