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 areas  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
An experiment with a floating egg Place an egg in a glass of fresh water and view it. Next add salt to the water and see if you can float the egg. How does this relate to the f

Pathophysiolog y   Normally the platelets are formed from megakaryocytes (stem cells) in the.  bone marrow. These cells mature, fragment and are released in  the blood strea

Which one of the following statements is correct with respect to AIDS? 1. The HIV can be transmitted through eating food together with an infected person 2. Drug addicts are

AMPHE T AMINE S - Commonly called pep pills or antisleep drugs. They increase physical & mental performance. Taken by truck drivers, student & night workers to keep

Agro Industrial-Baling and cubing Bailing is one of the most common processes used for the conservation of green fodders and grasses in many developed countries and attempts ha

Q. Identification and Care of Taxonomic collections? Collection of plant specimens is essential for taxconomic research. Herbarium specimens become a permanent record. Select t

where does the free nucleotides present in the nucleus come from

FEMALE REPRODUCTIVE SYSTEM - In female mammals the female reproductive system characteristically comprises of the ovary, uterus, placenta, vagina and vulva.

Q. What is the relationship between the ovulation and menstrual cycle? Ovulation is the releasing of the female gamete from the ovary and Ovulation is a periodical event that o

CILIA AND FLAGELLA Purkinj e first observed ciliary movement. Hodge studied detail structure of sperm flagellum. Manton studied structure of cilia in plants.