natural topography of Pak Flashcards

Question

active flood plain

Answer 1

Narrow strip of land on either side of the river = active flood plain Locally known as ‘bet’ or ‘khaddar’ land Inundated almost every year At the end of rainy szn, the land is marked w dry and braided channels rich in alluvium Active flood plain is found along all rivers except for southern half of ravi river due to low volume of water Where the Indus enters the Lower Indus plain, the flood plain is around 40km wide, making it an imp farming area

Answer 2

Meander and cover flood plains cover the area between alluvial terraces and active flood plain Only flooded when heavy monsoon rain Covered with ‘old alluvium’ alluvium deposited in the past Features found on this plain: abandoned channels, meaner scars and remains of oxbows, sometimes containing water

Answer 3

Alluvial terraces or bars are areas of higher ground between rivers formed by erosion of old alluvium Formed in upper Indus plain in Chaj, Rechna, Bari doabs Also called scalloped interfluves Sandal bar on rachna doab, Ganji bar on Bari Doab, Nili bar on Bari doab and Kirana bar on chaj doab = prominent alluvial terraces Surface of alluvial terraces = flat and has sw slope Ideal for agriculture w the help of irrigation Part of Bahawalpur Plain that has been reclaimed thru irrigation also falls within the boundary of the Indus plain Height of Bahawalpur plain identical w bars of doab and is also an alluvial terrace

Answer 4

Doab = land bw 2 rivers at their confluence Rivers → mature valley = a number of topographical features are formed on a doab due to erosion and deposition Doabs = favored areas for human activities eg farming, construction of settlements, building rail and roads and other industrial and business activities. A number of topographical features contribute to high population density in doab areas eg: Active flood plain = flooded every year = ideal land for crops which require lots of water eg rice and sugarcane Meander flood plains & cover flood plains - good locations for arable farming in fertile areas. Poor soil areas can be used for human settlements Well developed link canal irrigation system in doab areas → continuous supply of water all year Bar uplands = free from flooding as they are higher = ideal location for farming and human settlements, transport links, industrial estates etc

Answer 5

Located at foothills of Sulaiman, kirthar and himalayan mountains Most dominant features = alluvial fans or cones that develop eastward from the sulaiman and kirthar mountains Most rives/streams coming from sulaiman and kirthar ranges = low water flow =active only during rainy szn when they flow down the mountain swiftly As they reacht the foothills they become slow and split into narro channels that fan out on the slopes Material brought down by water is dropped within the narrow channels of the streams Gravel, sand and alluvium deposited by rivers form alluvial fans Extensive areas of alluvial fans on eastern side of sulaiman and kirthar ranges Smaller areas formed on sourthern side of siwaliks bw the rivers jhelum and chenab and also bw rivers chenab and ravi Sulaiman piedmont plain =derajat Piedmont plains = mainly agricultural

Answer 6

Indus delta = south of thatta Deltas = often triangular or fan shaped w main distributaries branching off the main river like ribs of a fan When a river flows into a sea, its speed is soon checked and it drops its load of alluvium to the sea floor Deposition of alluvium on the banks of distributaries = levees higher than the adjacent areas Sea water often fills troughs bw distributaies = swamps Indus delta = “tidal flats” w mangrove swamps Coastal area = generally low and flat Indus delta =east of karachi and includes Thatta, Keti, bandar etc Low population density bec it is exposed to waves and tides Agriculture limiteds due to swampy land covered w sea water, saline soil and low annual rainfall (125-250mm) Indus = worlds 5th biggest river delta and is home to 1M+ ppl Changes upstream in the Indus Basin affect delta region particularly bec of water taken for irrigation and loss of sediment Volume of Indus water reaching Indus delta reduced from 250M km cube to 100M km cube per year or less = causes sea water to flow further into delta channels, replacing fertile rice farms w salt marshes , and villagers havve been forced to move Global warming → sea levels rise → salt water will reach further inland At one time, Indus carried 300M tonnes of sediment per year into the arabian sea Over thousands of years this sediment created the delta By 2000, river was bringing less than 100 million tonnes of sediment per year Less sediment arriving to build up the delta → more easily eroded by sea

Answer 7

Prominent features These cuestas are ridges which in sindh are made of limestone Cuesta = steep slode on one side and gentle slpe on the other Rohri cuesta: height = 80m, 48 km long Ganjo Takkr cuesta: stretches southwards from hyderabad for a distance of 24 km These limestone ridges provide a firm foundation for the construction of barrages and add to scenic beauty of the area by varying the generally flat landscape

Answer 8

Indus plain = most productive region of Pak Relief and drainage = encourage growth of settlements Doabs of upper Indus plan, old and active flood plains of lower indus plain = excellent areas of farming Since ancient times, more than 80% of paks total cultivated area has been located in the indus plain Crops = grown all year round on fertile flat land w undulating slopes cotton, rice, sugarcane = summer, wheat = winter Flat land = ideal for canal irrigation and an extensive system has been developed to irrigate the fields Most developed region of Pak Infrastructure facilities are ez to provide Transport network of road rail and air is dense Electricity supplied to all urban centes eg lahore faisalabad gujranwala etc Many rural areas have also been supplied w electricity Has industries that use local raw materials eg cotton sugar chemical industry Industrial goods have large domestic and foreign market & population density varies from 50 to over 400 persons per sq km Upper Indus Plain Located in northern part of Indus plain River Indus and its tributaries flow her Nearly flat, undulating plain sloping towards southwest Avg width 1.4 km till kalabagh and 1.6 km near sukkur In its middle course in the north and enters its lower course towards south Both deposition and erosion take place w deposition becoming more dominant towards the south Alluvial terraces or bars formed bw rivers Piedmont plain w alluvial fans to the north and west Lower Indus Plain Located in southern part River indus flows here alone “ “ towards south Width = 1.6 In its lower course Deposition = main function ‘ ‘ non existent as indus flows alone ‘ ‘ to the west

Answer 9

3 desert areas Sindh sagar doab or Thal desert lies bw river Indus and river Jhelum Thar desert/sourth-eastern desert is in south eastern pak and has 3 main areas Cholistan Nara Tharparkar (Thar) Kharan desert Winds = most imp agent in shaping desert areas , and they change the landscape constantly Sand dunes, erosion of rocks and lack of vegeation = Pak deserts main features Rainfall = scanty, water table = v low Life in desert areas is predominantly affected by environment Lack of water and constant erosion of land by strong winds does not allow may productive human activities such as farming Deserts can be made productive if irrigation facilities are provided Major part of thair desert converted into farming land by canals from Sukkur barrage built on the indus Deserts may have rich mineral deposits, esp oil which is shown by the discovery of many oil and gas fields in the south eastern part of thar desert