Find out about the traditional systems of water harvesting/management in your region.
There are many traditional methods of water harvesting or management like khadin system, ponds, tals, canals, kohli tanks, rain water harvesting, saza kuva, and wells have been dug for the drinking water. Many water reservoirs are made by the government for the drinking water for humans as well as animals.
Water has been harvested in India since antiquity for the water management and for saving the water in drought conditions. By harvesting the rain drops with the direct connection from the rooftop where water is collected to the tanks where water is stored built in the courtyard, this is rain water harvesting system; khadin is also known as dhora and used to harvest surface runoff water for agriculture; ponds are the large water harvesting system for the groundwater recharge, infiltration etc; kohli tanks are the main water harvesting system or ancient harvesting system, it is cylindrical shaped formed underground and when rain comes it fills with water and keep it cool or fresh rainwater in it; kuva, wells, canals have been made by the artificial methods for the water harvesting or management.
As in the chapter showing the khadin, tanks and nadis as the traditional system of rain water management system in Rajasthan, also known as dhor; Bandharas and tals in Maharashtra; bundhis in Madhya Pradesh and Uttar Pradesh; Surangams in Kerala; and Kattas in Karnataka are used as ancient water harvesting systems. In largely level terrain, the water harvesting system is composed of earthen embankment or low, check dams are built across seasonally flooded gullies. Monsoon rain filled behind the structures only the large structure will hold the water for the long- range. The main purpose of the water management is not only to hold the water of the surface level but also holds the ground water level as well. Groundwater do not evaporate and spreads to fill the wells and provides moisture the earth and the soil respectively.
Suggest some approaches towards the conservation of forests.
We saw in this chapter that there are four main stakeholders when it comes to forests and wildlife. Which among these should have the authority to decide the management of forest produce? Why do you think so?
List five things you have done over the last one week to —
(a) conserve our natural resources.
(b) increase the pressure on our natural resources.
Find out the source of water in your region/locality. Is water from this source available to all people living in that area?
How can you as an individual contribute or make a difference to the management of (a) forests and wildlife, (b) water resources and (c) coal and petroleum?
Why should we conserve forests and wildlife?
Compare the above system with the probable systems in hilly/mountainous areas or plains or plateau regions.
Why do you think that there should be equitable distribution of resources? What forces would be working against an equitable distribution of our resources?
What changes can you make in your habits to become more environment-friendly?
What can you as an individual do to reduce your consumption of the various natural resources?
Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
What is a good source of energy?
Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
What is the difference between a reflex action and walking?
What is the importance of DNA copying in reproduction?
If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?
Why should a magnesium ribbon be cleared before burning in air?
Define the principal focus of a concave mirror.
You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
What will happen if a solution of sodium hydrocarbonate is heated? Give the equation of the reaction involved.
What were the criteria used by Mendeléev in creating his Periodic Table?
Find the power of a concave lens of focal length 2 m.
A student has difficulty reading the blackboard while sitting in the last row. What could be the defect the child is suffering from? How can it be corrected?
Redraw the circuit of Question 1, putting in an ammeter to measure the current through the resistors and a voltmeter to measure the potential difference across the 12 Ω resistor. What would be the readings in the ammeter and the voltmeter?
Can you think of reasons why more complex organisms cannot give rise to new individuals through regeneration?
What precaution should be taken to avoid the overloading of domestic electric circuits?
Why is damage to the ozone layer a cause for concern? What steps are being taken to limit this damage?
How is oxygen and carbon dioxide transported in human beings?
Which of the following statements is not a correct statement about the trends when going from left to right across the periods of periodic Table.
(a) The elements become less metallic in nature.
(b) The number of valence electrons increases.
(c) The atoms lose their electrons more easily.
(d) The oxides become more acidic.