Drought-water stress and adaptations, Biology

Drought

Drought refers to a condition of water shortage and it can result from many reasons. Frequently less than the normal rainfall is a common cause of drought. Less than 75% of normal rainfall may be defined as drought. We may, however, bear in mind that not only the total rainfall but its distribution in time is vitally important for crops. Small deficit (or surplus) in rain is not necessarily directly related to agricultural productivity. A severe drought reduces stream flow and recharging of aquifer. This results in lowering of water. table, loss of agricultural crops, wild life and aquatic life. Water level in lakes, streams and reservoirs drops due to failure of rains. As a result crop yield and fodder production suffer adversely resulting in food scarcity and human discomfort, and stress to livestock. The incidence of forest fue increases and overall conditions become difficult.

Due to the pressure of growing population over-exploitation of water resources has become a universal feature. Consumption of bsh water is due to rapidly growing urbanisation, industrialisation and mechanised agriculture which leads to over-exploitation of water resources. over-expioitation of fresh water resources can create severe limitation to growth and development. Excessive withdrawal of ground water in coastal areasĀ  has resulted in salt water intrusion into the aquifers . Consequently, the ground water has become unfit for human consumption and agriculture on account of high salinity. Ponds, bogs and streams are sites where ground water appears at the land surface. Excessive withdrawal of ground water and overdrawing of ground water lower the water-table as well as the level of water in lakes and streams and may completely dry them up.

Posted Date: 12/11/2012 12:32:46 AM | Location : United States







Related Discussions:- Drought-water stress and adaptations, Assignment Help, Ask Question on Drought-water stress and adaptations, Get Answer, Expert's Help, Drought-water stress and adaptations Discussions

Write discussion on Drought-water stress and adaptations
Your posts are moderated
Related Questions
What happens if platelets aren''t present in blood?

Actions of Estrogens The most general effect of the estrogens is to promote tissue growth. It is more pronounced in the accessory sex tissues. Estrogens stimulate cell divi

Explain The cardiovascular type of infantile beriberi? It manifests itself in babies between the ages of 2 and 4 months. The onset is acute with classical signs and symptoms of

What would be the likely immune response ability of an individual with a deletion of a Class II gene of the MHC on one chromosome and a nonsense mutation at the beginning of the sa

Explain the term-Diffusion Diffusion occurs from the side of greater concentration to the side of lesser concentration. In aqueous humour this occurs from the plasma side in th

What is the Importance of vitamin B 6 In the human and animal organisms, vitamin B 6 acts in the form of pyridoxal. In the form of 5'-orthophosphate (Pyridoxal-5'-phosphate),

Define Active or moderately active Lifestyles - physical activity? These people have occupations that p-e not strenuous in terms of energy demands, but involve more energy expe

A hypothesis can be used to predict the outcome of future testing. Which type of hypothesis is easier to test? A. It is easier to specify and test for a difference between two outc

Define Excretion of Methyl malonic acid in urine (Methyl malonil aciduria)? Methyl malonic acid is found only in traces in normal urine (1-2 mg/day). In vitaminĀ  B 12 deficie

can u show the different activities on the topic