Because fresh water has a slightly lower density, which means that more water has to be displaced to create the same amount of buoyancy.
Rivers and rain are the two that I can think of.
because Fresh water enters easly in the plant cells by endo osmosis. Thus, it causes better growth to the plant.
To revive fresh cut flowers, trim the stems at an angle, change the water daily, and place them in a cool location away from direct sunlight and drafts.
Stream discharge would increase if additional water enters it, such as from a rain storm or from melting snow.
It is not known when exactly when the fresh water supply will finish. However, as the world becomes more populated, the demand for water will increase and the 1% of available fresh water will be consumed faster.
because of the polution
Fresh water (of the same temperature) has the lower density ('lighter').
To store roses overnight and keep them fresh, trim the stems at an angle, place them in a clean vase with water, and store them in a cool location away from direct sunlight and drafts.
To keep hyacinths fresh in a vase, change the water every 2-3 days, trim the stems at an angle, and place them in a cool location away from direct sunlight and drafts.
To keep flowers fresh overnight, you can place them in a vase filled with water and add a floral preservative. Trim the stems at an angle and change the water daily. Keep the flowers in a cool location away from direct sunlight and drafts.
To keep your bouquet fresh overnight, place it in a clean vase with fresh water, trim the stems at an angle, remove any leaves below the waterline, and store it in a cool room away from direct sunlight and drafts.
increase in size untill it bursts.