Thursday, August 2, 2012

Lecture : 18 Definition of ecology and introduction to Environmental science


Note: This is for publication. Unauthorized reproduction is not permitted. III year. Students of ADAC&RI, Trichy are requested to go through lectures and leave comments appropriately
 
Lecture:18
 Definition of ecology and introduction to Environmental science
Definition of Ecology
Haeckel’s
·         “Surrounding outer world”
Odum (1969)
·         Study of interrelationship between organism and environment
·         Study of structure and function of ecosystems
Misra (1967)
·         Interaction of form, function and factors (Triangle of nature)
Krebs (1985)
·         Ecology is the scientific study of the  interactions that determine the distribution and abundance of organisms
Environmental science
Environmental science is an interdisciplinary academic field that integrates physical, chemical and biological sciences, (including but not limited to Ecology, Physics, Chemistry, Biology, Soil Science, Geology, Atmospheric Science and Geography) to the study of the environment, and the solution of environmental problems. Environmental science provides an integrated, quantitative, and interdisciplinary approach to the study of environmental systems.
Related areas of study include environmental studies and environmental engineering. Environmental studies incorporate more of the social sciences for understanding human relationships, perceptions and policies towards the environment. Environmental engineering focuses on design and technology for improving environmental quality.
Environmental scientists work on subjects like
1.   understanding of earth processes
2.   evaluating alternative energy systems
3.   pollution control and mitigation
4.   natural resource management
5.   the effects of global climate change.
Environmental issues almost always include an interaction of physical, chemical, and biological processes. Environmental scientists bring a systems approach to the analysis of environmental problems. Key elements of an effective environmental scientist include the ability to relate space, and time relationships as well as quantitative analysis.
Environmental science came alive as a substantive, active field of scientific investigation in the 1960s and 1970s driven by
(a) the need for a multi-disciplinary approach to analyze complex environmental problems,
(b) the arrival of substantive environmental laws requiring specific environmental protocols of investigation
(c) the growing public awareness of a need for action in addressing environmental problems.
Events that spurred this development included the publication of Rachael Carson's landmark environmental book “Silent Spring” along with major environmental issues becoming very public, such as the 1969 Santa Barbara oil spill, and the Cuyahoga River of Cleveland, Ohio, "catching fire" (also in 1969), and helped increase the visibility of environmental issues and create this new field of study.
Components
Atmospheric sciences focus on the Earth's atmosphere, with an emphasis upon its interrelation to other systems. Atmospheric sciences can include studies of meteorology, greenhouse gas phenomena, atmospheric dispersion modeling of airborne contaminants, sound propagation phenomena related to noise pollution, and even light pollution.
Taking the example of the global warming phenomena, physicists create computer models of atmospheric circulation and infra-red radiation transmission, chemists examine the inventory of atmospheric chemicals and their reactions, biologists analyze the plant and animal contributions to carbon dioxide fluxes, and specialists such as meteorologists and oceanographers add additional breadth in understanding the atmospheric dynamics.
Ecology is an interdisciplinary analysis of an ecological system which is being impacted by one or more stressors might include several related environmental science fields. For example, one might examine an estuarine setting where a proposed industrial development could impact certain species by water and air pollution. For this study, biologists would describe the flora and fauna, chemists would analyze the transport of water pollutants to the marsh, physicists would calculate air pollution emissions and geologists would assist in understanding the marsh soils and bay muds.
Environmental chemistry is the study of chemical alterations in the environment. Principal areas of study include soil contamination and water pollution. The topics of analysis include chemical degradation in the environment, multi-phase transport of chemicals (for example, evaporation of a solvent containing lake to yield solvent as an air pollutant), and chemical effects upon biota.
As an example study, consider the case of a leaking solvent tank which has entered the habitat soil of an endangered species of amphibian. As a method to resolve or understand the extent of soil contamination and subsurface transport of solvent, a computer model would be implemented. Chemists would then characterize the molecular bonding of the solvent to the specific soil type, and biologists would study the impacts upon soil arthropods, plants, and ultimately pond-dwelling organisms that are the food of the endangered amphibian.
Geosciences include environmental geology, environmental soil science, volcanic phenomena and evolution of the Earth's crust. In some classification systems this can also include hydrology, including oceanography.
As an example study of soils erosion, calculations would be made of surface runoff by soil scientists. Fluvial geomorphologists would assist in examining sediment transport in overland flow. Physicists would contribute by assessing the changes in light transmission in the receiving waters. Biologists would analyze subsequent impacts to aquatic flora and fauna from increases in water turbidity.

1 comment:





  1. Thank you. I just wanted to know where to ship it since I know now to keep producing it




    PhD Environmental Science

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