Fresh water-types of water found on earth, Biology

Fresh Water

Water, a universal solvent, invariably contains many soluble salts. In fresh water the total salt content remains under 15 percent. Different types of soluble salts released by weathering of rocks, soil erosion and decay of organic matter, readily dissolve in water.Dissolved salts are substances which have particular significance for floating aquatic vegetation and phytoplankton, since these organisms do not depend on the substratum for the supply of nutrients. Salts of nitrogen, phosphorus and silicon are most important substances found dissolved in fresh water. Nitrates, nitrites and ammonium salts are essential nutrients for plants. Dissolved silicates in the water are readily utilised by diatoms and sponges in the construction of their body structures e.g. shells in case of diatoms and spicules in case of sponges.

Many other elements like calcium, magnesium, manganese, iron, sodium, potassium, sulphur and zinc are found dissolved in water and influence the aquatic biota variously. Iron being an essential nutrient exists as ferrous oxide or ferrous sulphide in different fresh water bodies. Its availability is greatly modified by the pH of medium. Calcium is an essential element for plants as well as for animals. External coverings of arthopods and shells of molluscs and tubes of some worms need calcium carbonate.

Posted Date: 12/11/2012 12:24:13 AM | Location : United States







Related Discussions:- Fresh water-types of water found on earth, Assignment Help, Ask Question on Fresh water-types of water found on earth, Get Answer, Expert's Help, Fresh water-types of water found on earth Discussions

Write discussion on Fresh water-types of water found on earth
Your posts are moderated
Related Questions
Q. Define Myocardial infraction and stress testing? Prediction of disease is one of the primary functions of stress testing. We would like to be able to predict in each patient

Q. Why we use Overgloves? Overgloves are used when: supplies or equipment are retrieved or returned to the Dispensary or from the unit mobile the operator is charting

Q. What is meant by the arch reflex? In some situations the movement of the skeletal striated muscles does not depend upon commands of the superior motor neurons that it is not

What are the functional divisions of the nervous system? Functionally the nervous system can be separated into the somatic nervous system and visceral nervous system. The so

Define the Parenteral Nutrition Support? Parenteral nutrition support is the provision of dextrose, amino acids, electrolytes, vitamins, minerals and trace elements with or wit

what is condom???

what is the composition of enzymes ?

Parasite and host during incubation period Incubation period is the second stage in the process of a disease. It is the time between the day of infection to the appearanc

Diastolic dysfunction is  responsible for one third of cases of heart  failure alone and rest two  third of cases in  combination with systolic dysfunction. Diastolic dysfunction c

Describe the events which lead to the formation of (a) identical twins, (b) fraternal twins in detail