Lesson 1 - Ecology (Topics 1, 2, 3, and 4).pdf

Lesson 1: ECOLOGY ENVIRONMENTAL SCIENCE  Learning Outcomes At the end of this topic, students are expected to: Relate the study of environmental science to the civil engineering profession; Determine various renewable and non-renewable resources; Identify t...

Lesson 1: ECOLOGY ENVIRONMENTAL SCIENCE  Learning Outcomes At the end of this topic, students are expected to: Relate the study of environmental science to the civil engineering profession; Determine various renewable and non-renewable resources; Identify the abiotic and biotic components of the environment; Explain the diversity of biological organisms; and, Enumerate the different environmental pollutants and their sources.  Table Of Contents 01 02 03 Definition, Scope, and Importance Natural Resources Ecosystem 04 05 Biodiversity and Pollution and its Conservation Factors  01 Definition, Scope, and Importance  What is Environment? Why are people taking so much interest in Environment in recent years? Why are people so much concerned about the environmental issues of the day? Definition of Environment Definition of Environment Boring: ‘A person’s environment consists of the sum total of the stimulation which he receives from his conception until his death.’ Definition of Environment Douglas and Holland: ‘The term environment is used to describe, in the aggregate, all the external forces, influences and conditions, which affect the life, nature, behavior and the growth, development and maturity of living organisms.’ Definition of Environment Environment means all that surrounds us. Definition of Environment Environment performs different functions in relation to man: a. recreation and aesthetics, b. source of natural resources, c. sink for wastes produced by human activities.  Scope of Environment Scope of Environment The environment consists of four segments as under: 1. Atmosphere 2. Hydrosphere 3. Lithosphere 4. Biosphere 1. Atmosphere The atmosphere implies the protective blanket of gases, surrounding the earth. 1. Atmosphere a) It sustains life on the earth. b) It saves it from the hostile environment of outer space. c) It absorbs most of the cosmic rays from outer space and a major portion of the electromagnetic radiation from the sun. d) It transmits only here ultraviolet, visible, near infrared radiation (300 to 2500 nm) and radio waves. (0.14 to 40 m) while filtering out tissue-damaging ultraviolet waves below about 300 nm. 1. Atmosphere The atmosphere is composed of: 21% Oxygen 78% Nitrogen 1% Combination of Helium, Carbon Dioxide, Methane, and Hydrogen 2. Hydrosphere The Hydrosphere comprises all types of water resources oceans, seas, lakes, rivers, streams, reservoir, polar icecaps, glaciers, and ground water.  2. Hydrosphere About 2% of the water resources is locked in the polar ice caps and glaciers Only about 1% is available as fresh surface water – rivers, lakes 97% of the earth’s streams, and ground water supply is in water fit to be used for the oceans human consumption and other uses 3. Lithosphere Lithosphere is the outer mantle of the solid earth. It consists of minerals occurring in the earth’s crusts and the soil. 4. Biosphere Biosphere indicates the realm of living organisms and their interactions with environment, viz atmosphere, hydrosphere and lithosphere.  Elements of the Environment Environment is constituted by the interacting systems of physical, biological and cultural elements inter-related in various ways, individually as well as collectively. These elements may be explained as under: 1. Physical elements Physical elements are as space, landforms, water bodies, climate soils, rocks and minerals. They determine the variable character of the human habitat, its opportunities as well as limitations. 2. Biological elements Biological elements such as plants, animals, microorganisms and men constitute the biosphere. 3. Cultural elements Cultural elements such as economic, social and political elements are essentially manmade features, which make cultural milieu.  Elements of the Environment ENVIRONMENT Physical Elements Biological Elements Cultural Elements Atmosphere Hydrosphere Lithosphere Biosphere Economic Social Political Plants Microbes Animals Man Importance of Environmental Studies Importance of Environmental Studies Environment Studies enlighten us about the importance of protection and conservation of our indiscriminate release of pollution into the environment. At present a great number of environment issues, have grown in size and complexity day by day, threatening the survival of mankind on earth. We study about these issues besides and effective suggestions in the Environment Studies. Importance of Environmental Studies Environment studies have become significant for the following reasons: 1. Environmental Issues Being of International Importance 2. Problems Cropped in The Wake of Development 3. Explosively Increase in Pollution 4. Need for An Alternative Solution 5. Need To Save Humanity From Extinction 6. Need For Wise Planning of Development Importance of Environmental Studies 4. Need for An Alternative Solution It is essential, specially for developing countries to find alternative paths to an alternative goal. We need a goal as under: i. A goal, which ultimately is the true goal of development an environmentally sound and sustainable development. ii. A goal common to all citizens of our earth. iii. A goal distant from the developing world in the manner it is from the over-consuming wasteful societies of the “developed” world. Misra’s Report Misra (1991) recognized four basic principles of ecology, as under: i. Holism ii. Ecosystem iii. Succession iv. Conversation. Holism has been considered as the real base of ecology. In hierarchical levels at which interacting units of ecology are discussed, are as under: Individual