There is a low, that gas dissolution in water depends on temperature. The higher temperature the less amount of gas can be dissolved in water

DO concentration in water is dependant of water temperature but also of the partial pressure of oxygen (so of air) above the water. This is the Henry's law. If the partial pressure increases, then the DO concentration in water will also increase. When the altitude is increasing, the total atmospheric pressure decreases, and then the partial pressure of oxygen is also decreasing (assuming a constant proportion of O2 in air). You will then obtain a decrease of DO concentration with altitude elevation (at constant temperature and constant water composition of course).

the DISSOLVED OXYGEN of water is in a direct relationship with the atmospheric pressure. with raising altitude  the atmospheric pressure decreases. hence, atmospheric oxygen and also dissolved oxygen in water decreases.

it's an example when you go mountain climbing you feel to decrease oxygen pressure in the top of mountain.

Thank you all of you for such as valuable contributions. Do you have any reference paper for attribute ?

You can read this old article : Limnol. Oceanogr., 29(3), 1984, 620-632 , 1984, by the American Society of Limnology and Oceanography, Inc.

The concentration and isotopic fractionation of oxygen

dissolved in freshwater and seawater in

equilibrium with the atmosphere’

Bruce B. Benson and Daniel Krause, Jr.

This one is probably interesting too

This is an interesting question.  Here is a reference that I found which may be easier to read:

Jacobsen, D., Rostgaard, S., & Vásconez, J. J. (2003). Are macroinvertebrates in high altitude streams affected by oxygen deficiency?. Freshwater Biology, 48(11), 2025-2032.

Simple. D.O. is inversely proportional with altitude. As altitude increases D.O concentration decreases and when it decreases the D.O. concentration increases. Temperature have also a significant role on D.O. concentration.  

The answer is not straightforward. At high altitude the partial pressure of oxygen gas is low, therefore low [D.O.] in water may be expected (Law of Henry). However, at such high altitude, water temperatures are usually also low, favoring high [D.O.]. The balance between the effects of Henry's law and temperature is what will determine [D.O] and it's not uncommon to find these factors cancelling each other out leading to a situation where no direct relationship between altitude per se and [D.O.] can be inferred.

I think that is Emmanuel Naffrechoux right but strongly agree with Elias Rabson Chirwa. 

Dear Necla, 

There is no relation between them. Altitude and water quality are two independent things. DO may in some cases be affeceted by altitude, but  this is valid only for surface waters or shallow unconfined aquifers (piezometric level

Sure there is no direct relatioship between DO in surface water and altitude. But the two main parameters affecting DO in unpolluted (by DOM) surface water are temperature and partial pressure of dioxygen in air above water (Henry's law)... Numerous other parameters can also affect DO in water : wind speed, turbulent flow that increase air-water exchange and so DO in water, organic matter biodegradation or oxidation that decrease DO in water...etc)

http://www.savoirsenpartage.auf.org/chercheurs/8459/

Prof. Naffrechoux  is correct about DO. But do you limit water quality only on DO? Additionally, you have to consider which is the water body you want to assess its quality; is it an aquifer, a stream, a surface reservoir? The approach would be different.

There is is good correlation between dissolved oxygen saturation concentration and altude and water temperature.

I can send you more detailed information about these relationships if you want. 

But, of course, processes in the water as photosynthesis and oxidation of present organic matter will affect the actual DO concentration and vary during the day.

Thank you so much dear Anders Wilander. You can send imformation about this topic.

The actual amount of dissolved oxygen (in mg/L) will vary depending on temperature, pressure and salinity. First, the solubility of oxygen decreases as temperature increases. This means that warmer surface water requires less dissolved oxygen to reach 100% air saturation than does deeper, cooler water. Second dissolved oxygen decreases exponentially as salt levels increase . That is why, at the same pressure and temperature, saltwater holds about 20% less dissolved oxygen than freshwater. Third, dissolved oxygen will increase as pressure increases. This is true of both atmospheric and hydrostatic pressures. Water at lower altitudes can hold more dissolved oxygen than water at higher altitudes.

Dear Hany Mostafa thank you so much

Actually pv = constant ( may assume) so on earth vapor pressure is high because of temp. and its law at higher elevation because of low temp.so doest change much or lt's a matter of very good research if you are able to collect water samples between different altitudes having 3000 to 4000 m difference( some mountain have this height)

Dear Emmanuel Naffrechoux and Prof. P B Vekariya, Asstt. Prof., thank you so much for your contrubition