Environmental Determinism, possibilism and Neo-determinism

Environmental Determinism, possibilism and Neo-determinism

1. Module – 1 ENVIRONMENT AND ECOSYSTEM 1.1 Concept of Environmental System 1.2 Natural and Anthropogenic Environment 1.3 Components of Natural Environment 1.4 Concept and components of Ecosystem 1.5 Classification of ecosystems 1.6 Energy flow in the ecosystem 1.7 Changing man-environment relationships

2. Changing nature of man-environment relationship The relation ship between man and the nature has changed over time. Human being depend upon nature for his needs for ages now. However, he is now trying to be superior to the nature and changing the face of nature rapidly. There are three major approaches to study man-nature relationship: Environmental Determinism Possibilism Probabilism

3. Environmental Determinism This approach believes that natural environment determine patterns of human society. Characteristics of physical environment affects development of society. Mountainous region - economically backward Temperate climates – favorable for industrial development Coastal regions – produce fishermen and navigators. Alexander Humboldt Fredrick Ratzel

4. Possibilism This approach believe in importance of human impact in natural environment. Nature provides options – people choose best of it based on their abilities Nature sets limitations – but humans can overcome these limitations using technology Nature is advisor Human influence is more important than nature Humans are at first place, nature is secondary Vidal De la Blache Jean Brunce

5. Probabilism Approach that bridges between determinism and possibilism Man modifies the nature wherever necessary and sometimes adjust himself according to the nature. Neither man or nature is absolute controller. Stop and Go Determinism Use of natural resources when nature is favorable, stop using nature when it is unfavorable. Griffith Taylor

6. Bio-geo-chemical cycles “Inorganic chemical compounds transfer the energy in cyclic form (through biosphere, atmosphere, hydrosphere and lithosphere) is called bio-geo-chemical cycle Examples: hydrological cycle (water cycle), carbon cycle, nitrogen cycle

7. Hydrological / Water Cycle “The water cycles through biosphere in various forms (liquid – water droplets, solid – snow and gaseous – water vapor) and processes is called hydrological cycle” Processes involved in Hydrological cycle : Evaporation, Transpiration, Condensation, Precipitation, Runoff (surface and sub-surface)

8. Carbon Cycle

9. Carbon Cycle “The circulation of atmospheric carbon (CO2) through biosphere in various forms is called carbon cycle” Processes involved in carbon cycle: Photosynthesis, food chain and food web, formation of fossil fuels from buried dead bodies of plants and animals, burning of fossil fuels Release of atmospheric carbon (i.e. Carbon Di Oxide)

10. Nitrogen Cycle “The circulation of Nitrogen (N2) through biosphere in various forms is called Nitrogen cycle” Processes involved in carbon cycle: N itrogen fixation, consumption of nitrates by plants, nitrates transfer to animals through food chain, decay of dead bodies of plants and animals in soil, denitrification .

11. Summary: The energy flow of ecosystem refers to its functions. There are following forms of energy flow in the ecosystem. Food chain and Food web Bio-geo-chemical cycles The structure of energy flow in the ecosystem involves decrease in biomass/energy/number of individual organisms at higher trophic levels. This structure refer to “biomass / ecological pyramid”

12. Man – nature relationship has changed over the period of time. There are three approaches to study man-nature relationship: Environmental Determinism Possibilism Probabilism

13. Thank You