ECOLOGY and BIODIVERSITY Discussion Outline • Basic Ecology: Biodiversity, biomes, ecosystems, habitat, niche, population, and community. • Different levels of biodiversity. • Perhaps the most amazing feature of our planet is its rich diversity of life. Introduction • This vast multitude of life creates complex, interrelated communities where towering trees and huge animals live together with, and depend upon, such tiny life-forms as viruses, bacteria, and fungi. • Together, all these organisms make up delightfully diverse, self-sustaining ecosystems • These are also the same reasons why we need to have sustainable practices to maintain the beauty of our natural resources which is part of the study of Environmental Science and Engineering. ECOLOGY Ecology – a definition • The word ecology was coined by the German zoologist Ernst Haeckel, who applied the term oekologie to the “relation of the animal both to its organic as well as its inorganic environment.” • Ecology is the study of the relationships between organisms and their environment. • Some of the most pressing problems in human affairs—expanding populations, food scarcities, environmental pollution including global warming, extinctions of plant and animal species—are to a great degree ecological. Some Branches of Ecology • Applied Ecology - uses ecological principles to maintain conditions necessary for the continuation of present-day life on earth • Industrial Ecology – the branch takes the pattern and processes of natural ecosystems as a design for sustainability. "Industries Should Function Like Natural Ecosystems" • Ecological Economics – the branch integrates ecology and economics in such a way that economic and environmental policies are reinforcing rather than mutually destructive. “The Economy is a Subsystem of the Environment” • Urban ecology - urban ecology is the study of ecology in urban areas, specifically the relationships, interactions, types and numbers of species found in urban habitats. “Cities Are Ecosystems Too” Levels of Study Ecology • The six (6) levels of Ecology are: 1. Biosphere 2. Biome 3. Ecosystem 4. Community 5. Population 6. Individual/Organisms Biosphere • The entire inhabited part of the earth and its atmosphere including the living components is called the biosphere. • The biosphere is divided into three (3) divisions: 1. Hydrosphere – this includes all the water components (i.e. Oceans, Seas, Rivers, Lakes, etc.) 2. Lithosphere – comprises the solid components of the earth’s crust 3. Atmosphere – the gaseous envelope of the earth Biome • This is a large regional unit characterized by a distinct climate, vegetation, and wildlife. • The biome includes all associated developing and modified communities occurring within the same climatic region. • On a global scale, all the earth’s terrestrial biomes and aquatic systems constitute the biosphere. Ecosystem • The ecosystems are parts of nature where living organisms (biotic) interact amongst themselves and with their physical environment (abiotic). • The term ecosystem was coined by Sir Arthur Tansley in 1935. • An ecosystem has two (2) basic components: 1. Abiotic (non-living things) – comprises inorganic materials, such as carbon, nitrogen, oxygen, CO2, water etc. 2. Biotic (living things) – include producers, consumers and decomposers. Community • A community (biotic) is an assemblage of populations of plants, animals, bacteria and fungi that live in an area and interact with each other. • These are three types of biotic community, they are: • Animals • Plants • Decomposers (i.e., bacteria and fungi) Community - Niche • Niche is the interaction between members of a community; are also studied which is any of the following: • Predation • Parasitism • Mutualism • Commensalism • Competition • Scavenging • A variety of abiotic factors, such as soil type and climate, also define a species’ niche. • Each of the various species that constitute a community occupies its own ecological niche. • Informally, a niche is considered the “job” or “role” that a species performs within nature. Population • In ecology, a population is a group of individuals of the same species, inhabiting the same area, and functioning as a unit of biotic community. • For example, the individuals of elephants or tigers in an area constitute their population. Individual/ Organisms • They make the basic unit of study in ecology. At this level, the form, physiology, behavior, distribution and adaptation in relation to the environmental conditions are studied. • The organisms of the similar type have the potential for interbreeding, and produce fertile offspring, which are called species. • An organism is fully adapted to its environment. It has a definite life span including definite series of stages like birth, hatching, growth, maturity, senescence, aging and death. Habitat • It is a place where an organism or a community of organisms live, including all living and nonliving factors or conditions of the surrounding environment. • A host organism inhabited by parasites is as much a habitat as a terrestrial place such as a grove of trees or an aquatic locality such as a small pond BIODIVERSITY What is biodiversity? • Biodiversity comes from two words Bio meaning life and diversity meaning variability. • Biodiversity is the variety of all living things; the different plants, animals and micro organisms, the genetic information they contain and the ecosystems they form. Levels of Biodiversity • Biodiversity is usually explored at three levels • These three levels work together to create the complexity of life on Earth. • These levels are: 1. Genetic Biodiversity 2. Species Biodiversity 3. Ecosystem Biodiversity Genetic Biodiversity • Genetic diversity is the variety of genes within a species. Each species is made up of individuals that have their own genetic composition. • This means a species may have different populations, each having different genetic compositions. To conserve genetic diversity, different populations of a species must be conserved. • Not all groups of animals have the same degree of genetic diversity. • Kangaroos come from recent evolutionary lines and are genetically very similar. • Carnivorous marsupials, called dasyurids, come from more ancient lines and are genetically far more diverse. Species Biodiversity • Species diversity is the variety of species within a habitat or a region. Some habitats, such as rainforests and coral reefs, have many species. Others, such as salt flats or a polluted stream, have fewer. Ecosystem Biodiversity • Ecosystem diversity is the variety of ecosystems in a given place. • An ecosystem may be as large as the Great Barrier Reef or as small as the back of a spider crab's shell, which provides a home for plants and other animals, such as sponges, algae and worms ~DAS ENDE~ Assessment Discuss how human activities affect ecosystems at different ecological levels: focus on climate change, habitat destruction, pollution, and overexploitation. Then, propose at least two effective strategies to protect biodiversity and maintain ecological balance. Use real-world examples to support your arguments.
