Chapter 1-3 EnviSci PDF
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This document discusses environmental science and ethics, including different philosophical approaches such as anthropocentrism, biocentrism, and eco-centrism, and explores the nature of environments. The text further delves into environmental principles and approaches.
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The Nature of Environments Chapter 1 - Environmental Ethics Environment Ethics is a field of philosophy that focuses to ENCIRCLE or SURROUND an on the study of value or quality and seeks organism and includes the so...
The Nature of Environments Chapter 1 - Environmental Ethics Environment Ethics is a field of philosophy that focuses to ENCIRCLE or SURROUND an on the study of value or quality and seeks organism and includes the social to define what is right and what is wrong and cultural conditions that may irrespective of the culture and society. affect him BIOTIC and ABIOTIC factors Environmental ethics is the study of ○ BIOTIC - Living Factors moral perspectives, beliefs, attitudes, and ○ ABIOTIC - Non-living issues concerning the environment. Factors EVERYTHING that affects an Philosophical Approaches to organism in its lifetime Environmental Ethics Science systematized body of knowledge on a subject 1. Anthropocentrism (Human-centered chronologically arranged, Ethics) rationalized, in order The basic premise is Human beings are the central, most Environmental Science important species in the universe. the systematic study of our It sees the world focusing on environment and our place in it people and their needs explained as to how species interact with one another 2. Biocentrism (Life-centered Ethics) an Interdisciplinary field-relating one The fundamental premise is brach of knowledge to another-that All life has a standpoint, regardless includes both scientific and social of its value to humans aspects if human impact on the Some people believe that all living world organisms have the right to exist. All life is interdependent. 7 Environmental Principles 1. Nature Knows Best - Humans need 3. Eco-centrism to appreciate and recognize the It involves the essence of the importance of nature and follow it's system, rather than on individuals, rules species. 2. All forms of life are important - Each organisms plays a vital role in nature The environment itself has moral 3. Everything is connected to worth. everything else - food chain 4. Everything Change Environmental Attitudes a. Linear Any person concerned with the b. Random protection of the environment or who c. Cyclical believes that the sustainability of 5. Everything must go somewhere civilization depends on conserving natural 6. Ours is a finite earth aspects of the biosphere free from 7. Nature is beautiful, and we are pollution and maintaining biodiversity is stewards or God's creation called an Environmentalist. Specifically 1. Developmental Approach Chapter 2 - THE ENVIRONMENT It tends to be the most AND ORGANISMS anthropocentric and assumes that humanity is above all. Ecology - study of the ways organisms It assumes that the human race is interact with each other and with their and should be the master of nature nonliving surroundings. It yields to industrialization and modernization. Ecological Hierarchy 2. Conservationists Approach It is concerned with using natural areas and wildlife (fauna, flora, and microorganisms) to benefit present and future generations of human races and other forms of life. 3. Preservationist Approach Tends to be the most eco-centric towards the environment. It is concerned with the preservation of natural areas. protects the environment from harmful human activities Cornucopians are those who assume or believe that all parts of the environment (natural resources) are to be exploited for the advantage of humans Ecosystem - an interacting group of natural elements and the organisms in a given environment. It is a unit of interrelationships between biotic and abiotic factors. Biotic Components - living organisms present in the ecosystem. These organisms are autotrophs and heterotrophs. Autotrophs are also called "self-feeders" Detritivores that feed on detritus - or “producers”. They use the energy from remains of plants, animal feces, and other the sun (light energy) or chemical energy organic debris. to make their food. There are two types of autotrophs. The Abiotic Components 1. Photoautotrophs - use the energy Abiotic factors are the nonliving features of from sunlight to make their food in the environment that influence an the process called organism or group of organisms. They can photosynthesis. be organized into several categories. 2. Chemoautotrophs - use chemical 1. Energy is required by all organisms to energy from compounds to make sustain life. Light energy is the ultimate their food in the process called source of energy for almost all organisms chemosynthesis. in ecosystems. 2. Atmospheric gases. The most vital Heterotrophs are called "consumers." gases are oxygen, carbon dioxide, and These organisms cannot make their food, nitrogen utilized by plants and animals. primarily animals; and get their energy 3. Physical Characteristics. It includes from other plants and animals, and wind or air currents, soil, pH, and classify as: temperature. 4. Physiographic factors (nature of land surface). It is associated with the physical nature of the land surface/area. It includes altitude, the slope of the land, and the area's position with the sun or rain-bearing winds. Community Interactions Three types of interactions: Competition Predation Symbiosis ORGANISMS INTERACTION A. Obtaining food and energy. Some organisms can make their own food (producers), and other organisms have to get their food by eating other organisms(consumers). Decomposers - unable to make their Generalist - eat many different types of food. They decompose waste products foods and dead organisms for food and are Specialist - consumes only a specific type returned to the soil to be recycled and of food. used by plants again. B. Competition between organisms Scavengers feed on the soft tissues of arises when more than one organism dead animals. struggles to obtain the same essential resources in the same habitat. There are two types of competition. e. Mimicry is when organisms resemble 1. Interspecific competition - happens other species. Batesian mimicry is where between members of two or more different a harmless species imitates a harmful species over various limiting resources. It one. Mullerian mimicry occurs when often leads to extinction. various species share the same warning 2. Intraspecific competition arises coloration and resemble each other but between members of the same species have their own defenses. and may compete over mates, water, sunlight, territory, or food energy sources. Predation refers to a flow of energy between two organisms, predator and Natural Selection prey. Variation - Genetic variations are Latin word “praedari”, meaning 'to passed down plunder'. Competition - Some variations help survival Types of Predation Selection - Survivors pass down 1. Carnivory - predators kill and eat their their genetic variations prey. 2. Herbivory - predation involves the Mechanisms of Competition consumption of autotrophs, such as plants 1. Interference competition occurs when or photosynthetic algae. one species directly affects the ability of another to consume resources D. Symbiosis describes a close and 2. Exploitative competition occurs when often long-term relationship between two one species makes a resource or more different organisms. unavailable for consumption to another Mutualism - both species benefit species. Commensalism - one benefits, other is unaffected. Habitat is a place where an organism Parasitism - one benefits, other is lives. It is characterized by the physical harmed. environment, including distinctive physical features, vegetation, and the group of species living in it. C. Predation occurs when one species uses another species as food. Examples of these are: a. Mechanical defenses include the presence of armor in animals (spines) or thorns in plants to discourage predation and herbivory by preventing physical contact with the predator. b. Chemical defenses include odors and toxins released by plants and animals. c. Warning colors indicate aposematic coloration. d. Camouflage resembles its background. CHAPTER 3 POPULATION ECOLOGY Population - Group of individuals with the same species inhabiting the same area. Total numbers of individuals and the space they occupy per unit area. 3. Dispersion - distribution of the individuals throughout their range Properties of Population in an area. Clumped - aggregate in patches 1. Population Size - the precise like wolf pack attack prey number of individuals in an area Uniform - evenly distributed and Sampling method - used to make seen in territorial animal species inferences about the population as Random - unique pattern where a whole. each individual’s position is Quadrat - a square structure that independent of others must be placed at random locations within the habitat Mark and recapture - method in which animals are captured marked, and released back into the environment to mix with the rest of the population. 1. Exponential Growth describes populations that increase in numbers without any limits to their resources or encounter some other limitation 2. Population Density - indicates how crowded the population is. 2. Logistic Growth - As the Mortality Rate population size increases, Measure a number of deaths resources will be depleted, and the Depending on various factors like growth rate will slow down due to age and gender distribution limited resources. Life Table Statistical tool that summarizes the number of deaths of the population Longevity and life expectancy (age of survival) Migration/Immigration Movement of people from one place to another Push - where people leave the area due to problems. Pull - where people go to a certain area for their own good/interest Density-independent factors This Growth is not dependent on Demographic Data the density of the population. The Important data sources population increases at a rate determined PSA and census by its biotic potential. Some factors influence the population Density-dependent factors Age-sex structure - population This is a growth influenced by the parameter that refers to the density of the population. As the density of number of individuals of each sex the population increases, the resources and age group become limited. Sex Ratio Demography refers to the rate of males and Study of human populations, females in a population focusing on their size, structure, and distribution Demographic Helps to forecast population changes and their impacts on areas like healthcare, education, and economics Fertility Production of offspring/giving birth