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 are plant hormones? Plant hormones, also known as phytohormones, are substances that control the embryonic development and the growth of the adult plant.

Vegetative Development - Growth It is quantitative and irreversible change. It reflects an increase in size and volume of an organism. For example, the change in the size of a

Nekton - Aquatic Ecosystem This group contains animals which are swimmers. The nektons are relatively large and powerful as they have to overcome the water currents. The anima

Q. Where in eukaryotic cells does mRNA synthesis take place? To where do these molecules migrate? Messenger RNA molecules are synthesized within the nucleus, pass through gain

Chart of taxonomy of animal viruses

Explain the Reduction in free radical generation - Vitamin E? 1) Reduction in free radical generation: Vitamin E acts synergistically with selenium thereby reducing susceptibil

Pericarditis Pericarditis is a syndrome caused by inflammation of the pericardium. Causes i) Infections Bacterial : Pneumococci, Staphylococci, Streptococci,

XYY humans are fertile males. XXX humans are fertile females. What do these observations reveal about the mechanisms of sex determination and dosage compensation?

Assume that the blood volume of a rabbit is 0.5 liters. If the effective dose of the anesthetic urethane is 10 micrograms/mL, calculate the volume of a 25% urethane solution that m

Pituitary The pituitary is also known as hypophysis. It is composed of two embryologically distinct tissue. The anterior pituitary or adenohypophysis is derived from the roof