Final answer:
The gradual addition to land through natural causes is called deposition, which is a natural process where sediment accumulates to form new land, distinguishing it from erosion, weathering, and subsidence.
Step-by-step explanation:
Deposition occurs when sediment is transported from one location and accumulates in a new location, often resulting in the formation of new land over time. This process can be seen in action along riverbanks and coastlines where sediments are carried by water and eventually settle to build up the land. Erosion and weathering, on the other hand, work to break down landforms, and subsidence refers to the sinking or settling of the earth's surface, often due to natural or anthropogenic factors. When it comes to comparing the different processes affecting the earth's surface, it is important to distinguish between those that build up the surface, such as deposition, and those that wear it down, such as erosion and weathering, or cause it to sink, such as subsidence.