The formation of a sand dune in the desert or a delta near the water is based on how sediment is dropped and arranged. this process is known as

The formation of a sand dune in the desert or a delta near the water is based on how sediment is dropped and arranged. This process is known as -  Deposition

Deposition is defined as a geological process in which sediments, soil and rocks are added to any land form. Factors like water, ice, wind and gravity transport the surface materials, resulting in building up layers of sediment.

they each offer a fresh glut of resources to the organisms that can arrive and exploit them. as individuals and new species continue to appear, they actively and passively alter the environment. competition for shared resources increases, local abiotic and biotic conditions shift, and the relative abundances of species change accordingly. the process is called ecological succession, and it is one of the earliest and most well-known concepts in ecology.

if you add everything up correctly you should get 69 i got this because 50 plus 19 is it