Nature of physical geography

Nature of physical geography,Scope of physical geography, Content of physical geography

1. NATURE OF PHYSICAL GEOGRAPHY (Definition , Scope, &Development) Present By: DAYAMOY SANTRA B.A. IN GEOGRAPHYM(BU) M.A. STUDING(BU) Email id: [email protected]

2.   Physical geography is the branch of  natural science   which deals with the study of processes and patterns in the  natural environment  such as the   atmosphere ,  hydrosphere ,  biosphere , and  geosphere , as opposed to the cultural or  built environment , the domain of  human geography . Definition of Physical Geography:

3. We are know that   physical geography  examines and investigates natural phenomena spatially. ... Thus,  physical geography's scope  is much broader than the simple spatial study of  nature . It also involves the investigation of how humans are influencing  nature . Physical Geography studies- Geomorphology  - studies the various landforms on the Earth's surface . Pedology   - is concerned with the study of soils. Biogeography - is the science that investigates the spatial relationships of plants and animals . Hydrology - is interested in the study of water in all its forms . Scope of Physical Geography: It is evident from the foregoing discussion on the nature of physical geography that the detailed consideration of four components of the earth viz. lithosphere, atmosphere, hydrosphere and biosphere, are included in physical geography wherein characteristic features of these components are studied spatially and temporally.

4. The study of Geomorphology: The study of features resulting from the interactions between endogenetic and exogenetic forces involves the discussion of mode of denudational processes (weathering and erosion), hetherto termed as geomorphic processes, their mechanism of operation (machanism of erosion, transportation and deposition by running water- river, groundwater, sea waves, wind, glacier and periglacial agent) and resultant landforms.

5. The Study of Hydrospheric Component : The consideration of reliefs of the ocean basins (continental shelves, submarine canyons, continental slope, deep sea plains, ocean deeps etc.); thermal characteristics of ocean water; salinity (composition of seawater, sources and distribution of oceanic salinity); ocean deposits; ocean tides; ocean currents and coral reefs and atolls (their distribution and origin, coral bleaching etc.).

6. The study of Atmospheric component: The study of atmospheric component in cludes the discussion of composition and structure of atmosphere, elements of weather and climate, insolation and heat balance, terrestrial radiation balance and anthropogenic factors causing imbalance, air temperature, air pressure and winds (permanent or planetay winds, seasonal and local winds), characteristics and origin of monsoon, humidity and precipitation, air masses , frontogenesis, cyclones and anticyclones, world climate etc .

7. The study of biospheric component involves the consideration of components of biosphere (both abiotic and biotic), soil system, ecological production and energy flow in the biospheric ecosystem, circulation of elements in the ecosystem , biogeochemical cycles, evolution, dispesal and extinction of plants and animals, biomes and man, ecosystem stability and man, man and atmospheric environment (global radiation balance , ozone depletion, greenhouse effects and global warming), man and environmental processes , main-induced soil erosion and sedimentation , environmental degradation and pollution, extreme events, hazards and disaster, environ- mental planning and management, global environmental problems and international cooperaions . The study of biospheric component:

8. DEVELOPMENT OF PHYSICAL GEOGRAPHY: The discipline of physical geography has evolved through successive stages of its development in terms of methodology and approaches to study. After taking its birth in the philosophical ideas and reports of ancient thinkers, philosophers and historians of the ancient seats of civilization and culture e.g. Greece, Rome and Egypt, the science of physical environment attained its present status wherein different components were added from time to time. Previously physical geography concerned with only three components i.e., lithosphere, hydrosphere and atmosphere but biosphere has been recently added to this discipline . It is desirable that the historical development of four distinct branches of physical geography e.g., geomorphology, oceanography, climatology and biogeography should be discussed separately dealing with lithosphere, hydrosphere, atmosphere and biosphere respectively .

9. GEOMORPHOLOGY Geomorphology is a significant branch of physical geography. The term of geomorphology stems from three Greek words i.e., ge (meaning earth), morphe (meaning form) and logos ( meaning discourse). ' Geomophology may be defined as the scientific study of surface features of the earth's surface involving interpretative description of landforms, their origin and development and nature and mechanism of geomorphological processes which evolve the landforms' ( Savindra Singh, 1998). The subject matter of geomorphology is organized on the bases of (i) dimension and scale of relief features (landforms ), (ii) processes that shape the landforms, and (iii) the approaches to the geomorphic studies . The systematic study of landforms requires some fundamental knowledge of geology as the genesis and development of all types of landforms primarily depend on the materials of the earth's crust (rocks) and partly on the forces coming from within the earth. Certain principles of structural and dynamic geology are included in geomorphic studies.

10. First Order Relief Features :I nclude continents and ocean basins Second Order Relief Features : Mountains, plateaus, faults, rift valleys etc Third Order Relief Features : Running water , ground water, sea waves, wind, glacier and periglacial agents , are included in this categories The rapidly evolving discipline of geomorphology has undergone seachange in meth- odology and approaches to the study of landforms and related processes since 1945 when R.E. Horton introduced quantitative methods for the analysis of morphometric characteristics of fluvially originated drainage basins The most outstanding contribution to the advancement of geomorphological knowledge has been replacement of 'form geomorphology’ by 'process geomorphology' and postulation of 'functional theory' in place of 'evolution theory' and emergence of 'environmental geomorphology' as a new branch of geomorphology. As regards Indian contributions to geomorphology four centres of geomorphology have developed at Allahabad university, Calcutta university, Poona university and Central Arid Zone Research Institute (CAZRI), Jodhpur

11. OCEANGRAPHY The science of oceans i.e., oceanography includes marine geology, marine geomorphology, physical oceanography, chemistry of ocean water and bio-oceanography. The origin of ocean basins (continental drift and seafloor spreading), struc - ture of crust and mantle, characteristics of ocean deposits and characteristics and origin of marine landforms are studied in marine geology and geomorphology. Physical oceanography includes the consideration of physical properties of ocean water (e.g. temperature, pressure, salinity, den- sity , compressibility, viscosity, water masses and their distributional patterns) and dynamics of ocean water (e.g. sea waves, currents, tides, tsunamis etc .). Recently, marine meteorology is also included in oceanography wherein atmos - pheric conditions over ocean water are studied. Bio-oceanography includes the study of the char- acteristics , evolution, distribution and dispersal of marine organisms.

12. CLIMATOLOGY The gaseous envelop surrounding the earth is called atmosphere while the science dealing with the study of the atmospheric components and charactristics is called meteorology and climatology . Climatology includes the systematic and regional studies of the atmospheric conditions i.e. weather and climate. Weather refers to the sum total of the atmospheric conditions in terms of temperature, pressure, wind, moisture, cloudiness , precipitation and visibility of a particular place at any given time. In fact, weather denotes short term variations of atmospheric conditions and it is highly variable. On the other hand, climate is defined as aggregate weather conditions of any region in long-term perspective . There are three distinct branches of climatology e.g .----- (1) physical climatology, ( 2) regional climatology, and (3) applied climatology . Physical climatology deals with the interpretation of fac - tors responsible for the spatial and temporal variations of exchange of air circulation, heat and humidity.

13. BIOGEOGRAPHY Biosphere is a life supporting layer which surrounds the earth and makes plants and animal life possible without any protective device. The organic world or biosphere is that part of the earth which contains living organisms-the biologically inhabited soil, air and water' (J. Tivy , 1982). According to A.N. and A.H. Strahler (1977) all the living organisms of the earth and the environment to which these organisms interact make biosphere. Thus, the biosphere consists of all the living organisms (the biotic component), energy (the energy component) and physical environment (abiotic component) and there are continuous interactions between living organisms and physical environment and among the living organisms themselves .   Biogeography is an integrative field of inquiry that unites concepts and information from  ecology ,  evolutionary biology ,  taxonomy ,  geology ,  physical geography ,  palaeontology , and  climatology

14. Source : S . Sing ( physical geography), google etc Thank you