Environmental Science Lesson 1-2 PDF

**ESE\_LESSON 1-2** **Environmental Science** - The systematic study of the environment and humanity's relationship with it. - It's interdisciplinary, integrating natural sciences, social sciences, and humanities. - Mission-oriented: seeks new knowledge about the natural world and...

**ESE\_LESSON 1-2** **Environmental Science** - The systematic study of the environment and humanity's relationship with it. - It's interdisciplinary, integrating natural sciences, social sciences, and humanities. - Mission-oriented: seeks new knowledge about the natural world and human impacts on it. **Role** - Aware and appreciate the natural and built environment - Knowledgeable of natural systems and ecological concepts - Understand the current environmental issues; and - Able to use critical-thinking and problem-solving skills on environmental issues **Environmental Engineering** - A branch of engineering aimed at improving environmental quality and protecting people from adverse environmental effects like pollution. - Originated with the need to manage clean water and waste in ancient civilizations. - Became formalized in the mid-1700s, with engineers distinguishing themselves from military engineers by focusing on civilian infrastructure. **Environment** - From the French word \*environner\* meaning to encircle. - Includes the circumstances or conditions surrounding organisms. - Also encompasses the complex social or cultural conditions affecting individuals or communities. **History of Environmental Engineering** \- From the beginning of civilization, *environmental engineers* provided clean water and managed wastes, which was necessary whenever people congregated in organized settlements. \- In ancient cities, *the availability of a reliable water supply* became a defensive necessity. The engineers of antiquity were the builders of *wells and aqueducts*. \- During the *mid-1700s*, the term "civil engineering" was born. Engineers who built facilities for the civilian population began to distinguish themselves from engineers primarily engaged in matters of warfare. \- In the formative years of the United States, engineers were mostly *self-educated* or trained at the newly formed *United States Military Academy* \- With the arrival of *industrialization*, unsanitary conditions in the cities were unbelievably great due to the lack of water and waste management. **The Great Stink** was an event in Central London in *July and August 1858*, during which hot weather exacerbated the smell of untreated human waste and industrial effluent on the banks of the River Thames. The problem had been mounting for some years due to an ageing and inadequate sewer system that emptied directly into the Thames. The *miasma* from the effluent was thought to transmit contagious diseases, and three outbreaks of cholera before the Great Stink were blamed on the ongoing problems with the river. Following the Great Stink, civil engineers were tasked with ensuring that water was no longer a vector for disease transmission, focusing on eliminating waterborne diseases as the major objective by the late 19th century. **Ecology** - The scientific study of relationships between organisms and their environment. - Ecology helps understand life through the movement of matter and energy from living organisms to ecosystems. **Matter** - Anything that occupies space and has mass. - Exists in four states: solid, liquid, gas, and plasma. **Conservation of Matter** **"Matter is not created or destroyed but recycled."** - For example, when we discard waste, it doesn't disappear but goes elsewhere to be transformed or reused. **Atoms** - The smallest unit of an element, consisting of protons (positive charge), electrons (negative charge), and neutrons (neutral). \- Protons and neutrons form the nucleus, while electrons orbit the nucleus. **Elements** - Substances that cannot be broken down by chemical reactions. **Isotopes** - Different forms of an element that vary in atomic mass. **Compounds** - Substances composed of different kinds of atoms. **Molecules** - Groups of atoms that function as a unit. **Ions** - Atoms that gain or lose electrons and carry an electric charge. **Anions** - Negatively charged ions (e.g., chlorine ion Cl-). **Cations** - Positively charged ions (e.g., hydrogen ion H+). **Acids** - Substances that release hydrogen ions (H+) in water. **Bases** - Substances that bond with hydrogen ions. **pH** - Measures the strength of acids and bases. **Organic compounds** - are carbon-based molecules essential to life, including: - Lipids - Fats and oils. - Carbohydrates - Sugars, starches, cellulose. - Proteins - Chains of amino acids. - Nucleic Acids - DNA and RNA, which store and transfer genetic information. **Energy** - The ability to do work, such as moving matter or causing heat transfer. - **Kinetic Energy** - Energy in motion. - **Potential Energy** - Stored energy. - **Chemical Energy** - Stored in substances like food or fuel. - **Heat** - The transfer of thermal energy between objects of different temperatures. **UNITS OF ENERGY** - **One joule (J)** - is the work done when one kg is accelerated at one meter per second. - **One calorie (cal)** - is the amount of energy needed to heat one gram of pure water one degree Celsius. A calorie can also be measured as 4.184 J. **THERMODYNAMICS** - A study that deals with the transfer of energy in natural processes. - It deals with the rates of flow and the transformation of energy from one form or quality to another. **Laws of Thermodynamics** - **First Law** \- Energy is conserved; it can't be created or destroyed, only transformed. - **Second Law** \- Energy degrades with each transfer, meaning less energy is available for work after each transformation (e.g., energy lost as heat). **Cells** - Minute compartments within which the processes of life are carried out. - All living organisms are composed of **cells**. - **Single-celled organisms**: Bacteria, some algae, and protozoa. - **Higher organisms**: Have many cells, usually with many different cell varieties. For example, a **human being** is composed of several trillion cells of about **200 distinct types**. **Enzymes** - Specialized proteins that catalyze chemical - Create various structures. - Provide energy and materials to carry out **cell functions**. - Dispose of **wastes**. - Perform other functions of life at the cellular level. **METABOLISM** - This is the multitude of enzymatic reactions performed by an organism **ENERGY FOR LIFE** **Extremophiles** - Organisms living in extreme environments, such as deep ocean floors, which were once thought incapable of sustaining life. **Chemosynthesis** - A process where bacteria use chemical bonds from inorganic elements (e.g., hydrogen sulfide) to produce energy without sunlight. **Solar Energy** - type of energy that is generated by the sun and very essential to life. It is capable of producing heat, causing chemical reactions, or generating electricity. - Essential for life, it produces heat, causes chemical reactions, and generates electricity. - Provides warmth to most organisms, enabling survival within a narrow temperature range (40°C -- above, biomolecules break down; 0°C -- reactions slow). - Almost all organisms on the Earth\' s surface depend on solar radiation for life sustaining energy. **ECOLOGY** - This is the scientific study of relationships between organisms and their environment. **Species** - Organisms of the same kind capable of breeding and producing fertile offspring. **Population** - All members of a species living in a given area at the same time. **Biological Community** - Interacting populations within a particular area. **Ecosystem** - Biological communities interacting with their physical environments (both biotic and abiotic factors). **PHYSICAL ENVIRONMENTS** - **Abiotic factors** - is the nonliving components such as climate, water, minerals, and sunlight - **Biotic factors** -- examples are organisms and their products (secretions, wastes, and remains) and effects in a given area. **Productivity** - The amount of biomass (biological matter) produced in a given area during a given period of time - **Primary Productivity** - The production of biomass via photosynthesis, foundational to ecosystem growth. - **Secondary Productivity** - Biomass production by organisms consuming plants. - **Net Primary Productivity** - The remaining biomass after decomposers break down organic material. **Food Chain** - Sequence of energy transfers via consumption of organisms. **Food Web** - Complex network of interconnected food chains. **Trophic Levels** - derived from the Greek word \"trophe \" which means "food". The trophic level of an organism is the position it occupies in a food web. **Producers** - Photosynthetic organisms (plants, algae). **Consumers** - Organisms that eat producers (herbivores, carnivores, omnivores). **Scavengers** - Organisms that feed on dead animals (e.g., vultures). **Detritivores** - Organisms that feed on debris and dung. **Decomposers** - Bacteria and fungi that break down organic material, releasing nutrients back into the ecosystem. **Ecological Pyramids** - graphical representation of the relationship between different organisms in an ecosystem - Pyramid of Numbers - Represents the number of organisms at each trophic level. - Pyramid of Biomass - Shows the total biomass at each level, often largest at the base (producers). - Pyramid of Productivity - Displays energy flow and loss between trophic levels, measured in J/m²/yr. **Material Cycles** - water cycle distributes water among atmosphere, biosphere, surface, and groundwater. \- Maintenance of these conditions requires a constant recycling of materials between the biotic (living) and abiotic (nonliving) components of ecosystems. **HYDROLOGIC (WATER) CYCLE** - responsible for metabolic processes within cells, for maintaining the flows of key nutrients through ecosystem and for global-scale distribution of heat and energy. - **Evaporation** - Water turns into vapor from heat. - **Transpiration** - Water vapor released from plant leaves. - **Condensation** - Vapor cools and forms clouds. - **Precipitation** - Water falls as rain, snow, hail. **Runoff** - Water flows over land into bodies of water. **Percolation** - Water filters through soil to groundwater. **Groundwater** - Subterranean water is held in cracks and pore spaces. Depending on the geology, the groundwater can flow to support streams. **Water table** - The water table is the level at which water stands in a shallow well. **Carbon Cycle** - Photosynthesis takes in carbon dioxide, converting it into organic molecules. \- Carbon is released back into the atmosphere through respiration. **NITROGEN CYCLE** **Nitrogen Fixation** - Bacteria convert atmospheric nitrogen (N₂) into usable forms (nitrate NO₃ or ammonium NH₄). **Denitrification** - Nitrogen compounds converted back into nitrogen gas in oxygen-poor conditions. - **Atmospheric Presence**: Nitrogen gas (N₂) makes up about 78% of the Earth\'s atmosphere. - **Biological Relevance**: Nitrogen is essential for the synthesis of amino acids, proteins, and other complex organic compounds. Plants, in particular, rely on nitrogen for growth and development. **Key Processes in the Nitrogen Cycle** 1. **Nitrogen Fixation** - - - 2. **Nitrification** - - 3. **Denitrification** - - - 4. **Ammonification (Decomposition)** - - 5. **Role of Urine and Excrement** - - Phosphorus Cycle \- Unlike other cycles, phosphorus doesn't have an atmospheric form. It moves slowly from rocks through food webs. \- Phosphorus is a critical component in cells (ATP, proteins), limiting in ecosystems but also a pollutant in excess. **Cycle Pathway**: 1. **Weathering of Rocks**: The phosphorus cycle begins with the weathering of phosphorus-containing rocks. This process releases inorganic phosphorus into the soil. 2. **Uptake by Plants**: Inorganic phosphorus in the soil is absorbed by plant roots. Phosphorus is then incorporated into organic molecules within plants. 3. **Transfer through the Food Web**: Phosphorus moves through the food web as plants are consumed by herbivores, and herbivores are eaten by carnivores. It becomes part of the organic matter in these organisms. 4. **Decomposition**: When organisms die, decomposers break down their bodies, releasing phosphorus back into the soil as inorganic phosphorus. 5. **Runoff and Erosion**: Phosphorus can be transported from terrestrial environments to aquatic systems through runoff and erosion. 6. **Aquatic Accumulation**: In aquatic environments, phosphorus accumulates in sediments. Over time, these sediments can build up in water bodies and eventually reach the ocean. 7. **Geological Uplift**: Geological processes can uplift ocean sediments containing phosphorus, exposing them to terrestrial environments once more, making them available to the ecosystem again. **Note**: - phosphorus does not have a gaseous phase and thus does not cycle through the atmosphere. - The phosphorus cycle is a one-way path with a slow return to terrestrial environments through geological uplift. - Excessive phosphorus in aquatic systems can lead to environmental issues such as algal blooms and hypoxic conditions. **Biomes -** General types of communities with similar climate conditions, growth patterns, and vegetation types. - **Terrestrial Biomes** - Biological communities vary with temperature, precipitation, and latitude. - **Climate Graphs** - Used to describe and compare precipitation and temperature in different biomes. **Factors Affecting Biomes** **Temperature and Precipitation** - The two most important determinants in biome distribution on land. They help predict the kind of biological community likely to occur in an area without human disturbance. **Vertical Zonation** - Vegetation type changes rapidly from warm and dry to cold and wet as you go up a mountain. **Tropical Biomes** **Tropical Moist Forests**: - **Cloud Forests**: Found in areas with constant moisture from cloud cover. - **Tropical Rainforests**: Known for high biodiversity and dense canopy cover. **Tropical Seasonal Forests** - Drought-tolerant forests that appear brown and dormant during dry seasons but become vividly green during the rainy months. These forests are often called **Dry Tropical Forests**. **Tropical Savannas and Grasslands**: - **Grasslands** - Also known as prairies or steppes, these areas receive between **25 and 75 cm of rain per year**. - **Savannas** - Mixed woodland-grassland ecosystems where trees are spaced out so the canopy does not close. **Deserts -** Occur where precipitation is rare and unpredictable, typically with **less than 30 cm of rain per year**. - Deserts have sparse vegetation, but plants and animals are highly adapted to survive long droughts and extreme temperatures (both heat and cold). **Temperate Biomes** **Temperate Grasslands** - Occur in mid-latitudes where there is enough rain to support grass but not forests. Grasslands are a complex mix of grasses and flowering herbaceous plants (forbs). **Temperate Shrublands**: - Evergreen shrubs with small, leathery, sclerophyllous leaves form dense thickets. - **Periodic fires** are a major factor in plant succession in these regions. **Temperate Forests**: - Found between tropical and boreal regions in the temperate zone. This is the second largest biome on the planet. - **Deciduous Forests** - Lose their leaves in winter. They occupy moist, moderate climates and can re-grow quickly. - **Coniferous Forests** - Found in a wide range of temperature and moisture conditions. Conifers dominate in areas with limited moisture (cold climates where moisture is frozen or hot climates with seasonal drought). **Boreal Forests (Taiga)** - Found in mountainous areas at lower latitudes with dominant trees such as pines, hemlocks, spruce, cedar, and fir. - Boreal forests are **slow-growing** due to cold temperatures and short growing seasons, but they are still an expansive resource. - The extreme edge of the boreal forest, where it gradually gives way to open tundra, is known as **Taiga**. **Tundras -** Treeless landscapes found at high latitudes or on mountaintops, with a growing season of only **two or three months**. Tundras can experience frost at any time of the year, making them resemble cold deserts. - **Arctic Tundras -** Low productivity due to a short growing season. During midsummer, **24-hour sunshine** supports a burst of plant growth and insect life. - **Alpine Tundras** - Occur near mountaintops and have environmental conditions similar to arctic tundras. Plants here are adapted to **strong ultraviolet light** and intense conditions.