discuss two ways the hydrological cycle is critical to all other cycles.?

Answer 1

Earth's water is always in movement, and the water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above, and below the surface of the Earth. Since the water cycle is truly a "cycle," there is no beginning or end. Water can change states among liquid, vapor, and ice at various places in the water cycle, with these processes happening in the blink of an eye and over millions of years.

Although the balance of water on Earth remains fairly constant over time, individual water molecules can come and go in a hurry. The water in the apple you ate yesterday may have fallen as rain half-way around the world last year or could have been used 100 million years ago by Mama Dinosaur to give her baby a bath.

it also runs salt off the contenants into the oceans which is good for the oceans
http://www.palomar.edu/oceanography/salty_ocean.htm

Answer 2

Two ways in which the hydrological cycle is critical to the other cycles are 1) its role in the physical and chemical weathering process, and 2) its role in photosynthesis and primary production*. In both roles, water is a critical medium of transport.

The physical action of rainfall, runoff, and river flow contributes to the erosion process, in which chemical substances in soil and rock are broken down and transported (ultimately, to the ocean). Chemical processes associated with water also promote weathering and erosion, for example through the effects of acid rain. The moisture condition of the soil (dry vs. wet vs. saturated) is also a major controlling factor for decomposition of organic matter by microbes, and thus influences the carbon cycle by mediating the release of methane.

Water is an essential component of photosynthesis and primary production, which are fundamental biotic processes in the carbon cycle. Regions with abundant precipitation (and adequate temperature) can support high rates of photosynthesis and primary production, which transfers carbon from atmospheric carbon dioxide into plant biomass, a major reservoir in the carbon cycle.

*(Primary production by green plants is simply the result of photosynthesis over time--usually considered with regard to seasonal or annual periods. It can be further identified as "gross" primary production, which is the total production including the portion lost to respiration, or "net" primary production, which accounts for such losses.)