Chambal and Betwa join Yamuna at the Etawah district and Hamirpur town in Uttarpradesh. As we move to the East, Yamuna Joins Ganga at Triveni Sangam, Allahabad.Son River joins River Ganga near Patna, Bihar.

One of the most intensive conservation efforts in India, Project Tiger was launched in 1973. It envisaged the setting up of tiger reserves to help in maintaining the population of tigers. As per estimates, the number of tigers was about 40,000 at the beginning of the 20th century.

Black soils are poor in nitrogen, phosphorus and organic matter. The soils are generally rich in the montmorillonitic and beidellitic group of clay minerals. It is most suitable for the growth of cotton. It is also known or cotton soil as a reason.

The crude birth rate is the number of live births occurring among the population of a given geographical area during a given year, per 1,000 mid-year total population of the given geographical area during the same year.

A river drains the water collected from a specific area, which is called its 'catchment area'. An area drained by a river and its tributaries is called a drainage basin. The boundary line separating one drainage basin from the other is known as the watershed.

Playas occupy the flat central basins of desert plains. They require interior drainage to a zone where evaporation greatly exceeds inflow. A saline playa may be called a salt flat, salt marsh, salada, salar, salt pan, alkali flat, or salina.

Lignite, often referred to as brown coal, is a soft, brown, combustible, sedimentary rock formed from naturally compressed peat. It is considered the lowest rank of coal due to its relatively low heat content. It has a carbon content around 60-70%.

The preferred habitat of an Indian rhinoceros is alluvial flood plains and areas containing tall grasslands along the foothills of the Himalayas. Formerly, extensively distributed in the Gangetic plains, today the species is restricted to small habitats in Indo-Nepal terai and northern West Bengal and Assam.

In the north-west are the Aravali range, running in south-west, north-east direction forming a discontinuous ridge. Thar Desert lies to the west of Aravali ranges. The southern boundary is demarcated by the Vindhya Range with Kaimur Hills in the eastern extent. The Malwa plateau lies between Aravalis and Vindhyas.

The excessive shrinking of the geosynclines, caused folding and the surplus sediments were raised as the Himalayan mountains. The Himalayan uplift out of the tethys sea and the subsidence of the northern flank of the peninsular plateau resulted in the formation of a large basin.

India accounted for the largest number of people living below the international poverty line in 2013, with 30% of its population under the $1.90 – a - day poverty measure.

The Sundarbans mangrove forest, one of the largest such forests in the world (140,000 ha), lies on the delta of the Ganges, Brahmaputra and Meghna rivers on the Bay of Bengal. It is adjacent to the border of India's Sundarbans World Heritage site inscribed in 1987.

The Tropic of Capricorn lies at 23.5° south of the equator and runs through Australia, Chile, southern Brazil (Brazil is the only country that passes through both the equator and a tropic), and northern South Africa.

Green Index has been developed by United Nations Environment Programme.

The Greenhouse effect gases trap only the heat of Solar Radiation.

The Beas project consisting of Beas-Satluj link and pong dam at Beas is the joint venture of Punjab, Haryana and Rajasthan.

Nagarjuna Sagar Dam was built across the Krishna river at Nagarjuna Sagar where the river forms the boundary between Nalgonda District in Telangana and Guntur district in Andhra Pradesh states in India. The construction duration of the dam was between the years of 1955 and 1967.

Damodar River, river in northeastern India, rising with its many tributaries, notably the Bokaro and Konar, in the Chota Nagpur plateau of south-central Bihar state. It follows a generally eastward course for 368 miles (592 km) through West Bengal to join the Hugli (Hooghly) River southwest of Kolkata (Calcutta).

Central Ground Water Board (CGWB), a subordinate office of the Ministry of Water Resources, Government of India, is the National Apex Agency entrusted with the responsibilities of providing scientific inputs for management, exploration, monitoring, assessment, augmentation and regulation of ground water resources of the country. Central Ground Water Board was established in 1970 by renaming the Exploratory Tube wells Organization under the Ministry of Agriculture, Government of India. It was merged with the Ground Water Wing of the Geological Survey of India during 1972.

If you look down at our planet from outer space, most of what you see is water; 71% of the planet's surface is covered by ocean and it is because of this that the Earth is sometimes called "the water planet". Only about three-tenths of our globe is covered with land.

Jharia Coalfield is a large coal field located in the east of India in Jharia, Jharkhand. Jharia represents the largest coal reserves in India having estimated reserves of 19.4 billion tonnes of coking coal.

The percentage of earth surface covered by India is 2.4.

World Environment Day (WED) is celebrated on the 5th of June every year, and is the United Nation's principal vehicle for encouraging awareness and action for the protection of our environment.

It is currently the effective boundary between China and India, although its legal status is disputed by the Chinese government. The line is named after Henry McMahon, foreign secretary of British India and the chief negotiator of the convention at Simla.

India is the seventh largest country in the world, following Russia, Canada, USA, China, Brazil and Australia, in that order. It occupies 2.4% of the world's total land but supports 16.7% of the population.

The imaginary line joining the land projecting towards the sea which is the landward limit of internal seawater is called Base Line.

The North Eastern Railway is one of the 18 railway zones in India. It is headquartered at Gorakhpur and comprises Lucknow, Varanasi and Izzatnagar or Bareilly division.

The range is known as Sahyadri in Maharashtra and Karnataka. The Western Ghats meets the Eastern Ghats at Nilgiris in northwestern Tamil Nadu. Nilgiris connects Biligiriranga Hills in southeastern Karnataka with the Shevaroys and Tirumala hills.

The major peaks like Mt. Everest, Kanchenjunga, Makalu, Dhaulagiri, Mansalu, Chooyu, Nanga Parbat and Annapurna all are situated in The Greater Himalayas (Himadri).

K2 also known as Mount Godwin-Austen or Chhogori at 8,611 metres (28,251 ft) above sea. K2 is the highest point of the Karakoram range and the highest point in both Pakistan and Xinjiang.