Principles of Environmental Science - Chapters 1 & 2 Vocabulary

Comprehensive vocabulary flashcards covering major themes, scientific methods, historical thinkers, systems dynamics, thermodynamics, energy flow, biomolecules, and biogeochemical cycles from Chapters 1 and 2.

Environmental Science

The study of natural systems around us using scientific approaches of observation and analysis, drawing on multiple fields of knowledge to understand and solve environmental problems.

Throughput

The amount of resources that a system or society uses and disposes of.

Ecosystem Services

The essential resources and functions provided by environmental systems, such as carbon capture, water purification, temperature regulation, decomposition, and food provisioning.

Sustainable Development

Development that meets the needs of the present without compromising the ability of future generations to meet their own needs, as defined by Gro Harlem Brundtland.

Human Development Index (HDI)

A composite metric monitored by the United Nations incorporating quality-of-life indicators such as life expectancy, education, and income to evaluate human well-being across regions.

Empiricism

A fundamental principle of science stating that observations of real and observable phenomena can help us understand natural processes.

Uniformitarianism

A scientific principle stating that natural forces and processes at work today are the same as those that shaped the world in the past.

Parsimony

A scientific principle stating that when two explanations are plausible, the simpler explanation is preferable.

Deductive Reasoning

Logical reasoning that derives specific conclusions from general laws or principles known to be true.

Inductive Reasoning

Logical reasoning that formulates general rules or principles based on numerous specific observations.

Hypothesis

A testable and proposed explanation for a specific observation or question formulated during scientific inquiry.

Scientific Method

An orderly sequence of scientific inquiry consisting of identifying a question, forming a testable hypothesis, developing a test, collecting data, interpreting results, and reporting for peer review.

Natural Experiment

An experimental approach involving the observation of events or conditions that have already occurred in nature without direct manipulation.

Manipulative Experiment

An experiment in which specific conditions are deliberately altered while all other variables are controlled or held constant.

Blind Experiment

An experimental design in which the researcher does not know which group received the treatment until after data analysis, reducing researcher bias.

Double-Blind Experiment

An experimental design in which neither the subject nor the researcher knows who is in the treatment group and who is in the control group.

Paradigm Shift

A major change in scientific consensus that occurs when a majority of scientists accept that an established explanatory framework no longer adequately explains new evidence.

Critical Thinking

Logical, orderly, and analytical assessment of ideas, evidence, and arguments by breaking down statements, evaluating sources, and questioning assumptions.

George Perkins Marsh

Author of "Man and Nature" (1864) who warned against resource waste and destruction, sparking the beginning of environmental protection in North America.

Gifford Pinchot

The first chief of the U.S. Forest Service who advocated for pragmatic utilitarian conservation to manage forests rationally for human use and future generations.

Utilitarian Conservation

A resource management philosophy promoted by Theodore Roosevelt and Gifford Pinchot asserting that nature and forests should be saved to provide homes and jobs for people.

John Muir

First president of the Sierra Club who spearheaded the nature preservation movement, arguing that nature has an intrinsic right to exist for its own sake based on aesthetic and spiritual values.

Aldo Leopold

A wildlife ecologist and founder of the Wilderness Society who advocated for a land ethic and emphasized managing human demands rather than just natural resources.

Rachel Carson

Author of "Silent Spring" (1962), which alerted the public to the ecological and health hazards of toxic chemical pollution and launched the modern environmental movement.

Bill McKibben

An author, educator, and activist who demands political action to address climate change.

Van Jones

An environmental activist who advocates for a "green-collar" economy by creating jobs focused on solar energy installation and energy efficiency upgrades.

Wangari Maathai

Winner of the 2004 Nobel Peace Prize and founder of the Green Belt Movement in Kenya, promoting sustainable development and environmental restoration.

System

A network of interdependent components and processes with energy and materials flowing from one component to another.

State Variables

Compartments within a system that store resources such as energy, matter, or water.

Open System

A system that receives inputs of energy or matter from its surroundings and produces outputs that leave the system.

Closed System

A system that exchanges no energy or matter with its surroundings.

Positive Feedback Loop

A feedback mechanism in a system that amplifies or increases a process or component.

Negative Feedback Loop

A self-correcting feedback mechanism in a system that suppresses or diminishes a process or component to maintain stability.

Emergent Properties

Characteristics of an entire whole system that are complex and greater than the simple sum of its individual parts.

Principle of Conservation of Matter

The law stating that under ordinary circumstances, matter is neither created nor destroyed, but is instead recycled continuously.

Atom

The smallest particle that exhibits the characteristics of a chemical element, consisting of a nucleus of protons and neutrons circled by electrons.

Isotopes

Forms of a single element that contain the same number of protons but differ in their number of neutrons and atomic mass.

Ion

An atom or group of atoms that has gained or lost electrons, acquiring a net negative or positive electrical charge.

Cation

A positively charged ion formed when an atom loses one or more electrons.

Anion

A negatively charged ion formed when an atom gains one or more electrons.

Ionic Bond

A chemical bond formed by the electrical attraction holding oppositely charged ions together.

Covalent Bond

A chemical bond formed when atoms share one or more pairs of electrons.

Acids

Substances that readily surrender hydrogen ions ($\text{H}^+$) in water, resulting in a pH value below 7.

Bases

Substances that readily bond with hydrogen ions ($\text{H}^+$) and release hydroxide ions ($\text{OH}^-$) in water, resulting in a pH value above 7.

pH Scale

A logarithmic scale measuring hydrogen ion concentration to represent acidity or basicity, ranging from 0 (highly acidic) to 14 (highly basic), with 7 being neutral.

Kinetic Energy

The energy contained in moving objects.

Potential Energy

Stored energy that is available for use.

First Law of Thermodynamics

The law stating that energy is conserved; it can be transformed from one form to another, but cannot be created or destroyed.

Second Law of Thermodynamics

The law stating that with each successive energy transfer or transformation in a system, less energy is available to do work, causing entropy to increase.

Entropy

The measure of disorder or randomness in natural systems, which naturally increases over time according to the second law of thermodynamics.

Chemosynthesis

The biological process by which certain organisms extract energy from inorganic chemical compounds, such as hydrogen sulfide ($\text{H}_2\text{S}$), in environments lacking sunlight.

Photosynthesis

The process by which green plants, algae, and some bacteria convert light energy, carbon dioxide ($\text{CO}_2$), and water ($\text{H}_2\text{O}$) into high-energy carbohydrates (glucose) and oxygen ($\text{O}_2$).

Cellular Respiration

The chemical process by which cells break down glucose and oxygen to release energy for metabolic work, releasing carbon dioxide and water as by-products according to: $\text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 \rightarrow 6\text{H}_2\text{O} + 6\text{CO}_2 + \text{released energy}$

Species

A group of organisms of the same kind that are genetically similar enough to breed in nature and produce live, fertile offspring.

Population

All the individual members of a single species living in a given area at the same time.

Biological Community

All of the populations of different species living and interacting together in a specific area.

Ecosystem

A complex assemblage of a biological community interacting with its non-living physical environment.

Primary Productivity

The rate at which organic matter or biomass is produced by primary producers (autotrophs) in an ecosystem through photosynthesis.

Net Primary Productivity

The amount of organic material produced by photosynthesis in an ecosystem minus the portion consumed by respiration and decomposers.

Food Web

A complex diagram showing the interconnected individual food chains and feeding relationships among species within an ecosystem.

Trophic Level

An organism's specific feeding status or position within an ecosystem's food web or energy pyramid.

Autotrophs

Primary producers that synthesize their own food using sunlight, water, carbon dioxide, and mineral nutrients.

Heterotrophs

Consumers that obtain chemical energy and nutrients by consuming other organisms or organic matter.

Scavengers

Organisms, such as jackals and vultures, that clean up and feed on the dead carcasses of larger animals.

Detritivores

Organisms, such as ants and dung beetles, that consume organic litter, debris, and dung.

Decomposers

Organisms, such as fungi and bacteria, that complete the final breakdown and recycling of dead organic materials.

Ecological Pyramid

A graphical representation showing the decrease in energy, biomass, or number of organisms across successive trophic levels from producers to top carnivores.

Biogeochemical Cycling

The continuous movement and recycling of essential elements and nutrients (such as water, carbon, nitrogen, phosphorus, and sulfur) through living organisms and the physical environment.

Hydrologic Cycle

The biogeochemical cycle detailing the continuous circulation of water through evaporation, transpiration, precipitation, percolation, and runoff across oceans, land, and atmosphere.

Carbon Fixation

The process by which photosynthetic organisms capture gaseous carbon dioxide ($\text{CO}_2$) and convert it into organic molecules like sugars.

Carbon Cycle

The biogeochemical cycle by which carbon is exchanged among the atmosphere, terrestrial biosphere, oceans, and geological deposits.

Nitrogen Fixation

The biological process in which nitrogen-fixing bacteria combine atmospheric nitrogen gas ($\text{N}_2$) with hydrogen to produce ammonia ($\text{NH}_3$) or ammonium ($\text{NH}_4^+$).

Nitrification

The biological process in which nitrifying bacteria oxidize ammonia ($\text{NH}_3$) or ammonium ($\text{NH}_4^+$) into nitrites ($\text{NO}_2^-$) and then into nitrates ($\text{NO}_3^-$) that plants can absorb.

Denitrification

The process by which denitrifying bacteria convert nitrates ($\text{NO}_3^-$) back into nitrogen gas ($\text{N}_2$) and nitrous oxide ($\text{N}_2\text{O}$), returning nitrogen to the atmosphere.

Nitrogen Cycle

The complex biogeochemical cycle by which atmospheric nitrogen is fixed, assimilated by plants, passed through consumers, decomposed, and returned to the atmosphere.

Limiting Nutrient

An essential chemical element or compound (such as phosphorus or nitrogen) that is scarce relative to demand and limits biological growth within an ecosystem.

Phosphorus Cycle

The biogeochemical cycle tracking the movement of phosphorus through rock weathering, soil, living organisms, waterways, and marine sedimentation without a gaseous atmospheric phase.

Sulfur Cycle

The biogeochemical cycle governing the movement of sulfur through rocks, ocean vents, atmospheric sulfur dioxide ($\text{SO}_2$), precipitation, and biological processes.