Knowledge in Geography

Watershed

WatershedGeographic area through which water flows across the land and drains into a common body of water, whether a stream, river, lake, or oceanWatershed boundary will more or less follow the highest ridgeline around the stream channels and meet at the bottom or lowest point of the land where water flows out of the watershed, the mouth of the waterwayDrainage basinAlso known as catchment basinAn area of land where surface water from rain, melting snow, or ice converges to a single point at a lower elevationUsually converses at the exit of the basin, where the waters join another water body viz. river, lake, reservoir, estuary, wetland, or seaHence it is an area drained by tributary streams that coalesce into a main channel Watershed DivideThe line, which divides the surface runoff between two adjacent river basins, is called the topographic water divide, or the watershed divide.It marks the highest points between the basins, but isolated peaks within a basin may reach higher elevations than any point on the divide.

Stream or Flowing River Patterns

Stream or Flowing River PatternsThe combined effects of climate and geology on the catchment topography yield an erosion pattern, which is characterized by a network of streams.Some of the frequently observed stream patterns are as follows -  Dendritic River PatternRiver channel follows the slope of the terrainHomogeneous beds of uniform resistance to erosionStreams run in all directions without definite preference to any one particular regionExample → Indo – Gangetic Plains  Rectangular River PatternRegions that have undergone faultingProvide uniform resistance to erosionStreams Meet at right angle approx.Develops on strongly joined rocky terrainExample → Vindhya Mountains of India   Trellis River PatternRiver joined by tributaries at approx. right angleDevelops in folded topography; alternate layers of hard & soft rocksLonger streams have preference to one directionTributaries have preference to right angle to the main streamExample → Appalachian Mountains of North America & Singhbhum (Chotanagpur Plateau)   Radial River PatternStreams flow in different directions from central peakOutflowing rivers, away from a central point, analogous with the spokes of a wheelGenerally referred to rivers flowing through dome Mountains and volcanoesExample → Rivers Narmada, Son and Mahanadi originating from Amarkantak Hills; Girnar Hills (Kathiwar, Gujarat), and Mikir Hills of Assam   Pinnate River PatternMain stream runs in one directionTributaries join it at oblique angle  Parallel River PatternMain stream runs in one directionTributaries also join it running in the same direction

Forests of India

Tropical Evergreen ForestsAv. Rainfall → Above 200 cmAv. Temp. → 24* CFound at Hot & Humid areas of IndiaTall & Dense → 45 – 60 mHardwood ForestsFound at WGs, A & N islands & Eastern IndiaSunrays unable to reach earth surfaceTrees compete & rise high to get sunlightEx. Rubber, Coconut, Ebony, Mahogany, PalmsDeciduous ForestsAv. Rainfall → 100 -200 cmAv. Height → 25 – 45 mShed their leaves in summers due to shortage of waterFound at Shiwaliks, Ganga valley, WGs, NE IndiaEconomically very important forestsEx. Sal, Teak, Shisham, Sandalwood, Deodar, MahuaTropical dry ForestsAv. Rainfall → 50 – 100 cmLess dense & Small in size → 6 – 9 mRoots are thick & long to use underground waterThick Bark to prevent undue evaporationFound at Punjab, Haryana, MP, Eastern Rajasthan, Central Deccan PlateauMost of the areas are used for agricultureDwarf Deciduous trees and long- grasses grow in these regionsEx. Neem, Shisham, Babul, Pipal, MangoArid or Desert ForestsAv. Rainfall < 50 cmProminent features →Small leaves, Thick Bark, Long RootsIndian wild date is common in these desertsFound at Western Rajasthan, SW Haryana & Punjab, In some parts of GujratEx. Small sized kikar, Babul, Acacia, Bushes & ShrubsTidal ForestsThese forests grow along the coast and on the edges of the deltasFamous for Mangrove & Sundari TreesConsists of thick Bushes & FernsKnown as Halophytes →Tolerant of SalinityFound at Sundarbans, A & N Islands, Deltas of Mahanadi, Godavari, Krishna & KaveryMountain forestsMountain forests vary considerably along the slopes of mountainOn the foothills of Himalayas, upto a height of 1500 meters, evergreen trees, (Sal, teak, bamboo and cane) grow abundantly.On higher slope between 1,500 meters to 3,500 meters, temperate conifer trees (pine, fir, oak, maple, deodar, laurel spruce, cedar) grow.At the higher altitude of the Himalayas, rhododendrons and junipers are found.Beyond these vegetation belts, alpine grasslands appear up to snowfield

Forest Cover of India

Forest Cover of India  34 Percent geographical area under forest cover till 2015The total forested area in India is about 63.73 million hectares.In the last 10 years, forest cover in the country has increased by 3.31 million hectares, showing an average 0.46% increase every year.Problems of ForestryOver grazingForest FireReckless Cutting of TreesJhum CultivationGovernment InitiativesReserve & Protected forestsVan Mahotsav Programme → Thousands of trees are planted every year in the months of July and AugustForest Research Institute at Dehradun →For promotion and preservation the forests properlyNational Forest policy National Forest Policy, 1988Conservation of Biodiversity, Afforestation & Check of soil erosion33 % Geographical area shall be forest coveredDevelop Social Forestry → (Agro Forestry, Community Forestry & Forestry by officials) Social ForestryMainly to reduce pressure on traditional forests by planting trees esp. for fuel wood, Timber & other social suppliesHelp in checking water and wind erosion by acting as shelter beltsEmployment & additional income generationAgro ForestryPlanting trees & agricultural crops together on farms for food, fuel, fodder, timber & fruitsForestry + AgricultureTrees bind soil and acts as shelter belts thus check soil erosionDeep roots of trees trap new nutrients and bring them close to the surfaceLeguminous trees fix atmospheric nitrogen, thus improves fertility of the soilSoil nutrient increases due to addition and deposition of leaf litter Community ForestryTrees Planted by community in their respected colonies Forestry by officialsTrees planted by forest departments to cater needs of community esp. along Roads, canals, Railways etc. 

Forest & Wildlife Protection Programmes by Government

Forest & Wildlife Protection Programmes by GovernmentNational ParkRelatively large area consisting of one or more ecosystems, operates at National LevelNo human activity or settlement allowed i.e. human interference is totally prohibitedVillagers cannot graze their animals + Extremely strict rules about jungle produce collection for ex. Honey Wildlife SanctuaryRegulated human activities are allowed → Grazing of animals, Firewood collection, Tourismcan be created for a particular specie which is not the case with national; operates at State LevelA sanctuary can be upgraded to a National park but not vice versa Biosphere ReserveUnique ecosystem of terrestrial & coastal areas internationally recognized by UNESCO under Man and Biosphere (MAB) programmePeople are allowed to live, own private land & carry own traditional activities but only in outer zoneCore zoneCentral area that has to be kept undisturbed of all activities except research (which don’t disturb wildlife)Buffer zoneSome light activities like tourism, fishing, grazing etc. are allowed which don’t disturb the core zone. Research activities are encouraged hereTransition zoneOutmost part & not delimited but activities have to be harmonious with the biosphere reserveConservation ReservesCan be declared by the State Governments in any area owned by the governmentParticularly the areas adjacent to National Parks and Sanctuaries and those areas which link one Protected Area with anotherSuch declaration should be made after having consultations with the local communities Community ReservesCan be declared by the State Government in any private or community land, not comprised within a National Park, Sanctuary or a Conservation ReserveMainly where an individual or a community has volunteered to conserve wildlife and its habitat

Advantages and Disadvantages of Gravity Dams

Advantages and Disadvantages of Gravity Dams

dams in India

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lakes in India

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Migration chapter geography

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Human Development geography

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Human Settlements geo

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Land Resources geography

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