BIO104 Ecology PDF - 1st SEM 2024

BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 Biological organization refers to the hierarchy of Lesson 1: Ecology complex biological structures, from atoms to the...

BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 Biological organization refers to the hierarchy of Lesson 1: Ecology complex biological structures, from atoms to the biosphere. Its significance lies in helping scientists understand how life is structured and functions at Significance different levels, from molecules (e.g., DNA) to ecosystems. Each level, such as cells, tissues, organs, Deals with the higher levels of biological and organisms, depends on the interactions within organization. and between levels, highlighting the interdependence Investigates how organisms interact with each of life. This organization is essential for studying other and with the abiotic factors processes like energy flow, genetic information in the environment. transfer, and species interactions, all of which are Describes the habitat (address) as well as the niche fundamental to biology and ecology. (profession) of organisms. Investigations mostly This organization is essential for the efficient functioning of life and allows for the complexity and diversity observed in the natural world. Etymology and Definitions German Ernst Haeckel coined the word “Oekologie” in 1869. From two Greek words “oikos” – house or the family of household, and “logos” – study of. First Definitions: The relationship of the animal to its organic as well as its inorganic environment (Haeckel, 1869). The study of relationships among organisms and between organisms and their environment. ABIOTIC ECOLOGY is the scientific study of the relationship between organisms and their environment Three meanings of Ecology in today’s society The relation of any organism to its environment The professional science and its variants 1 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 The political or philosophical movement Ecology focuses specifically on the interactions incorporating environmental concerns – NO!! between organisms and their environments, studying ecosystems, populations, species interactions, energy Ecology is the study of the relationship between flow, and nutrient cycling. Organisms and their environment Environmental science is an interdisciplinary field Ecology - people confuse it with terms such as that combines ecology with other sciences (chemistry, environment and environmentalism (BIG NO!). geology, physics, and social sciences) to study the environment as a whole. ECOLOGY is neither. Environmentalism is activism with a stated aim of Ecology is the study of natural relationships, while protecting the natural environment, particularly from environmental science applies those ecological the negative impacts of human activities. principles, along with other scientific knowledge, to address environmental challenges. Environment refers to the surroundings or conditions where organisms live, including all “Just as we humans are constrained by the laws of physical, chemical, and biological factors. physics when we build airplanes and bridges, we should also be constrained by the principles of Environmentalism is a social and political ecology when we alter the environment”. movement aimed at protecting and conserving the natural environment, often focusing on issues like The quote emphasizes that, just like we follow pollution, deforestation, and climate change. physical laws when building, we must follow ecological principles when altering the environment. Ecology is a science, while environmentalism is an Ignoring these rules can harm ecosystems and lead to advocacy or action-oriented movement. This environmental problems. distinction is important because ecology provides the data and insights, while environmentalism uses those Organisms interact with the environment in the insights for conservation and activism. context of the ecosystem The eco– part of the word relates to the environment. The –system part implies that the ecosystem functions as a collection of related parts that function as a unit. Any example of a system? the eco system consists of two basic interacting components: the living, or biotic, and the nonliving (physical and chemical), or abiotic 2 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 Ecological systems form a hierarchy, with each level representing increasing complexity: Scientific Method  The scientific method is the sequence of 1. Organism – An individual living being. steps that scientists follow, when attempting 2. Population – A group of organisms of the same to answer a question or explain an observation. species living in a specific area.  Has been used for some of the most famous 3. Community – Multiple populations of different discoveries. species interacting in a shared environment.  a powerful tool for understanding nature 4. Ecosystem – A community plus its physical environment, involving interactions between living Observation (biotic) and non-living (abiotic) components. 5. Landscape – A mosaic of interconnected  All science begins with observation (if ecosystems, where ecological processes occur across something cannot be observed, it cannot be larger spatial scales. investigated by science) 6. Biome – Large areas with similar climate, flora,  The observation need not be direct and fauna, such as tundra or rainforest.  Observation must be repeatable 7. Biosphere – The global sum of all ecosystems, ○ to minimize unsuspected bias encompassing all life on Earth. Bias - when an individual might observe what they want or think they ought to observe Noticing and describing phenomena in a careful and detailed manner. This step involves gathering data and identifying patterns or issues that spark curiosity. Question/ Defining a Problem  forming a question regarding the observation that has been made For example, an ecologist working in the Subdivisions of Ecology prairie grasslands of North America might observe that the growth and productivity of Autecology – the study of single organism or grasses varies across the landscape. populations of single species and their relationship to their environment.  Possible Question (Formulated): Synecology – the study of groups of organisms (or  ○ what environmental factors result in the populations) observe variations in grass land productivity associated to form a functional unit of the across the landscape? environment 3 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024  The question typically focuses on seeking an -Independent variable: The factor being explanation for the observed patterns manipulated or changed. - Dependent variable: The factor being measured or  Followed by Doing Background Research observed. - Control group: The group in which conditions Based on the observation, a specific question is remain constant, used for comparison. formulated. This question should be focused and testable, guiding the direction of the research. Data Collection  During the experiment, data is gathered and Hypothesis recorded, often through measurements or  Once a question (problem) has been observations. established, the next step is to develop a hypothesis Analysis  The data is analyzed to determine if it  A hypothesis is an educated guess about what supports or refutes the hypothesis. This may the answer to the question may be involve statistical analysis or interpreting trends and patterns in the data.  The process of developing a hypothesis is guided by Conclusion  experience and knowledge, and it should be a  Based on the analysis, conclusions are drawn. statement of cause and effect that can be If the data supports the hypothesis, it may be tested accepted. If not, the hypothesis is rejected or modified, and further testing may be needed. Example: the ecologist might hypothesize that the observed variations in the growth and Communication productivity of grasses across the prairie  The results are shared with the scientific landscape are a result of differences in the community, typically through publications or availability of soil nitrogen presentations, allowing others to review, replicate, or build upon the work. A possible explanation or answer to the question is proposed. A hypothesis is an educated guess that is Peer review involves publishing the results for other testable and can be supported or refuted by scientists to review and check for error, bias, or uncontrolled variables. experimentation. Margin of error is an estimate of how different a Experiment result is from the actual value. ○ All experiments have errors in measurement, A controlled test is designed to investigate the design, or other factors. hypothesis. Variables are defined: Bias 4 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 Carl Ludwig Willdenow  Bias is the preference for an experiment to 1765–1812 turn out in a certain way. He pointed out that similar climates supported o Bias can be caused by a desire for vegetation similar in form, even though the species fame, money, or simply protecting were different your job.  Blind experiments reduce bias by ensuring the test subjects do not know whether they in Friedrich Heinrich Alexander von Humboldt the experimental or control group. 1769–1859 o Eliminates the placebo effect. Humboldt Current - west coast of South America  Double-blind experiments prevent both He spent five years exploring Latin America, scientists and subjects from knowing which is including the Orinoco and Amazon rivers the experimental group. plant association - correlated vegetation with environmental characteristics Correlation and Causation Led the way for new scientists to explore  Correlation is observed when there are relationship of plant biology and plant geography statistical variables which have a relationship that not be expected by chance alone. Johannes Warming 1841–1924  Correlation suggests, but does not always studied the tropical vegetation of Brazil mean causation, which occurs when one He wrote the first text on plant ecology, variable directly influences the other. Plantesamfund – has tremendous influence in the development of ecology Ecology History integrated plant morphology, physiology, taxonomy, and biogeography into a coherent whole The genealogy of ecology is complex and intertwined with a wide array of scientific advances that have Charles Darwin occurred in other disciplines within the biological and 1809–1882 physical sciences. Voyage on the Beagle Working for years on notes and collections from Theophrastus – a friend of Aristotle, who wrote this trip about the relations between organisms and the compared similarities and dissimilarities among environment. organisms within and among continents Ecology as we know it today has vital roots in plant He noted how successive groups of plants and geography and natural history. animals, distinct yet obviously related, replaced one In the 1800s, botanists began exploring and another mapping the world’s vegetation Theory of evolution and on the origin of species 5 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 Thomas Malthus George Evelyn Hutchinson 1766–1834 Eugene Odum Economist Howard T. Odum advanced the principle that populations grow in a The use of radioactive tracers, a product of the geometric fashion, doubling at regular intervals until atomic age, to measure the movements of energy and they outstrip the food supply nutrients through ecosystems a “strong, constantly operating force such as the use of computers to analyze large amounts sickness and premature death” would restrain the of data (systems ecology), the application of general population system theory and methods to ecology From this concept Darwin developed the idea of “natural selection” as the mecha nism guiding the Richard Hesse and Charles Elton evolution of species Elton’s Animal Ecology (1927) and Hesse’s Tiergeographie auflogischer grundlage (1924), Frederic E. Clements translated into English as Ecological Animal 1874-1945 Geography, strongly influenced the development of sought some system of organizing nature animal ecology in the United States proposed that the plant community behaves as a complex organism or superorganism that grows and Charles Adams and Victor Shelford develops through stages to a mature or climax state were two pioneering U.S. animal ecologists Adams published the first textbook on animal Arthur G. Tansley ecology, A Guide to the Study of Animal Ecology 1871-1955 (1913). Shelford wrote Animal Communities in Opposed Frederic E. Clements Temperate America (1913) Tansley advanced a holistic and integrated Shelford gave a new direction to ecology by ecological concept that combined living organisms stressing the interrelationship between plants and and their physical environment into a system, which animals he called the ecosystem Karl Mobius Raymond. A. Lindeman developed the general concept of the community. 1915-1942 essay “An Oyster Bank is a Biocenose” (1877), traced “energy-available” relationships within a Mobius explained that the oyster bank, although lake community dominated by one animal, was really a complex 1942 paper - “The Trophic-Dynamic Aspects of community of many interdependent organisms. Ecology,” marked the beginning of ecosystem He proposed the word biocenose for such a ecology, the study of whole living systems community. The word comes from the Greek, Influenced young scientists the ideas of organic meaning life having something in common nutrient cycling and feeding levels, using the terms producers and consumers W. C. Allee, A. E. Emerson, Thomas Park, Orlando Park, and K. P. Schmidt 6 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 Principles of Animal Ecology Closely associated with population and evolutionary It emphasized feeding relationships and energy ecology is community ecology, with its focus on budgets, population dynamics, and natural selection species interactions. and evolution to understand the origin, maintenance, and consequences of species diversity within ecological William Wheeler communities. animal behavior of ants landscape ecology - spatial processes that linked adjacent communities and Charles Carpenter ecosystems animal behavior of South American monkeys Example: The development of aerial photography and later the launching of satellites by the U.S. space Konrad Lorenz and Niko Tinbergen program provided scientists with a new perspective Pioneering studies on the role of imprinting and of the surface of Earth through the use of remote instinct in the social life of animals, particularly birds sensing data and fish, gave rise to ethology conservation ecology - impact of changing land use Spawned an offshoot called behavioral ecology, on natural ecosystems exem plified by L. E. Howard’s early study on applies principles from different fields, from territoriality in birds ecology to economics and sociology, to the Behavioral ecology is concerned with intraspecific maintenance of biological di versity and inter specific relationships such as mating, restoration ecology - application of principles of foraging, defense, and how behavior is influenced by ecosystem development and function to the natural selection restoration and management of disturbed lands global ecology - understanding Earth as a system In 20th century the study of populations branched into two fields: Summary: Population ecology - concerned with population Ecology has so many roots that it probably will growth (including birthrates and death rates), always remain multifaceted—as the ecological regulation and intraspecific and interspecific historian Robert McIntosh calls it, “a polymorphic competition, mutualism, and pre dation discipline.” Insights from these many specialized Evolutionary ecology - a combination of population areas of ecology will continue to enrich the science as genetics and population ecology which deals with the it moves forward in the 21st century role of natural selection in physical and behavioral adaptations and speciation. Ecology is a diverse field with many branches and Focusing on adaptations, physiological ecology is specializations, making it inherently multifaceted. As concerned with the responses of individual organisms ecological historian Robert McIntosh describes it as a to temperature, moisture, light, and other “polymorphic discipline,” this diversity allows for a environmental conditions. wide range of insights and perspectives. These specialized areas, such as community ecology, 7 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 ecosystem ecology, and conservation biology, A portion of the electromagnetic spectrum, contribute to a deeper understanding of ecological separated into solar (shortwave) and thermal systems. As we progress into the 21st century, this (longwave)radiation. Ultraviolet, visible, and infrared richness will continue to enhance the science of light waves represent only a small part of the ecology, helping us address complex environmental spectrum. To the left of ultraviolet radiation are X- challenges. rays and gamma rays (not shown).  The exact nature of the energy emitted, however, Lesson 2: Climate depends on the object’s temperature Weather is the combination of temperature, humidity, precipitation, wind, cloudiness, and other atmospheric conditions occurring at a specific place and time. (short term) Climate is the long-term average pattern of weather and may be local, regional, or global  The hotter the object is, the more energetic the Surface Temperatures Reflect the Difference emitted photons and the shorter the wavelength between Incoming and Outgoing Radiation The wavelength of radiation emitted by an object is a Solar radiation (the electromagnetic energy function of its temperature. The Sun, with an average emanating from the Sun)—travels more or less surface temperature of 5800°C, emits shortwave unimpeded through the vacuum of space until it radiation as compared to Earth, with an average reaches Earth’s atmosphere. surface temperature of 15°C, which emits longwave radiation. Wavelength (lambda) Frequency (v)  Some of the shortwave radiation that reaches the surface of our planet is reflected back into space.  The quantity of shortwave radiation reflected by a surface is a function of its reflectivity, referred to as its albedo. 8 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024  Albedo is expressed as a proportion (0–1.0) of Incoming shortwave radiation – reflective shortwave the shortwave radiation striking a surface that is radiation = net shortwave radiation absorbed by reflected and differs for different surfaces. the surface  Examples: some of the energy absorbed by Earth’s surface  surfaces covered by ice and snow (0.8–0.9) (both land and water) is emitted back out into space  Forest (0.05) as terrestrial longwave radiation.  The global annual averaged albedo is The amount of energy emitted is dependent on the approximately 0.30 temperature of the surface (the hotter the surface the more radiant energy will emit). Most of the longwave radiation emitted by Earth’s surface is absorbed by water vapor and carbon dioxide in the atmosphere. This absorbed radiation is emitted downward toward the surface as long-wave atmospheric radiation Albedo is a measurement from of how reflective a (keeps near surface temperatures warmer a.k.a. surface is GREENHOUSE EFFECT caused by  Black objects have an albedo of 0.8.  More than 80% of infrared energy is reflected.  It is the difference between the incoming shortwave (solar) radiation and outgoing longwave (terrestrial) radiation that defines the 9 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 net radiation and determines surface decreasing net surface radiation from the equator temperatures toward the poles. Net radiation is the difference between the amount What are the factors influencing this variation? of shortwave (solar) radiation absorbed by a surface and 1. At higher latitudes, solar radiation hits the surface the amount of longwave radiation emitted back into at a steeper angle, spreading sunlight over a larger space by that surface. LW, longwave; SW, shortwave area 2. solar radiation that penetrates the atmosphere at a  If the amount of incoming shortwave radiation steep angle must travel through a deeper layer of air exceeds the amount of outgoing longwave radiation = surface temperature increases In the process, it encounters more particles in the atmosphere, which reflect more of the shortwave  if the quantity of outgoing longwave radiation radiation back into space exceeds the incoming shortwave radiation = surface temperature decreases  Example: during the night  On average, the amount of incoming shortwave radiation intercepted by Earth and the quantity of long-wave radiation emitted by the planet back into space is balanced the average surface temperature of our planet remains approximately 15oC  However, from the global map of average annual As one moves from the equator to the poles, surface there is a distinct latitudinal gradient of there is a decrease in the average amount of solar 10 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 (shortwave) radiation reaching Earth’s surface. Two factors influence this variation. First, at 1. Summer: When a hemisphere (Northern or higher latitudes (a), solar radiation hits the Southern) is tilted toward the Sun, it experiences surface at a steeper angle, spreading sunlight more direct sunlight, resulting in longer days and over a larger area than at the equator (b). Second, warmer temperatures—this is summer. solar radiation that penetrates the atmosphere at a steep angle must travel through a deeper layer of 2. Winter: When a hemisphere is tilted away from air the Sun, it receives less direct sunlight, leading to shorter days and cooler temperatures—this is winter. The result of the decline in net radiation with latitude is a distinct gradient of decreasing mean 3. Spring and Autumn: During these transitional annual temperature from the equator toward the poles seasons, neither hemisphere is tilted directly toward or away from the Sun. The sunlight is more evenly Surface temperatures are determined by the balance distributed, resulting in moderate temperatures. between incoming and outgoing radiation. The incoming radiation primarily comes from the Sun in This axial tilt, combined with Earth's orbit around the the form of shortwave solar energy (visible light and Sun, creates the cyclical pattern of seasons. ultraviolet rays), which heats the Earth's surface. The Earth then emits outgoing radiation as longwave Why do the hot days of summer give way to the infrared energy, radiating heat back into space. changing colors of fall, or the freezing temperatures and snow-covered landscape of winter to the blanket If the incoming radiation exceeds outgoing radiation, of green signaling the onset of spring? the surface warms up, raising temperatures. Conversely, if outgoing radiation exceeds incoming, The seasonal changes, such as the hot days of the surface cools down. Factors like greenhouse gases, summer giving way to the colorful foliage of fall or cloud cover, and surface properties (e.g., water, land, the cold winter transitioning into green spring growth, are driven by the Earth's axial tilt and its orbit or ice) influence this balance, regulating Earth's around the Sun. Here's how it works: surface temperatures.  Summer to Fall: As the Earth orbits the Sun, the Intercepted Solar Radiation and Surface hemisphere that was tilted toward the Sun begins Temperatures Vary Seasonally to tilt away. This reduces the amount of direct sunlight and causes temperatures to cool. The decreased light and cooler temperatures signal What gives rise to the seasons on Earth? plants to prepare for winter, leading to the changing leaf colors as trees stop producing The seasons on Earth are caused by the tilt of the chlorophyll. Earth's axis (approximately 23.5 degrees) as it orbits  Winter to Spring: As the Earth continues its around the Sun. This axial tilt causes different parts orbit, the hemisphere that was tilted away from of the Earth to receive varying amounts of sunlight the Sun begins to tilt back toward it, receiving throughout the year. Here's how it works: more sunlight and warmth. This increase in light 11 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 and temperature stimulates plant growth, melting snow, and signaling the arrival of new leaves and In the equatorial region there is little seasonality green landscapes. (variation over the year) in net radiation, temperature, or day length Earth, like all planets, is subject to two distinct motions (rotation and revolution). Seasonality systematically increases from the While it orbits the Sun, Earth rotates about an axis equator to the poles that passes through the North and South Poles, giving rise to the brightness of day followed by the darkness At the Arctic and Antarctic circles (66.5° N and S, of night (the diurnal cycle) respectively), day length varies from 0 to 24 hours over the course of the year. The days shorten until the Earth travels about the Sun in an ecliptic plane. winter solstice, a day of continuous darkness. The days lengthen with spring, and on the day of the Earth’s axis of spin is not perpendicular to the summer ecliptic plane but tilted at an angle of 23.5° solstice, the Sun never sets As a result, as Earth follows its elliptical orbit about Geographic Difference in Surface Net Radiation the Sun, the location on the surface where the Sun is Result in Global Patterns of Atmospheric directly overhead at midday migrates between 23.5° Circulation N and 23.5° S latitude over the course of the year As we discussed in the previous section, the average net radiation of the planet is zero the amount of incoming shortwave radiation absorbed by the surface is offset by the quantity of outgoing longwave radiation back into space. Otherwise, the average temperature of the planet would either Changes in the angle of the Sun and circle of increase or decrease illumination during Earth’s yearly orbit (equinoxes and the winter and summer solstices are illustrated). there are regions of positive (surplus) and negative Note that as a result of the 23.5° tilt of Earth on its (deficit) net radiation north– south axis, the point of Earth’s surface where the Sun In fact, there is a distinct latitudinal pattern of surface is directly overhead migrates from the tropic of Radiation Cancer (23.5° N) to the tropic of Capricorn (23.5° S) over the course of the year 12 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 The sinking air at the poles raises surface air pressure, forming a highpressure zone and creating a pressure gradient from the poles to the equator The cooled, heavier air then flows toward the low- pressure zone at the equator, replacing the warm air rising over the tropics and closing the pattern of air circulation If Earth were stationary and without irregular RECALL: the equatorial region receives the largest landmasses, the atmosphere would circulate like the annual input of solar radiation and greatest net previous figure radiation surplus. Air warmed at the surface rises because it is less dense than the cooler air above it Air heated at the equatorial region rises to the top of the troposphere, establishing a zone of low pressure at the surface This low atmospheric pressure at the surface causes air from the north and south to flow toward the equator The resulting convergence of winds from the north and south in the region of the equator is called the  As a result, air masses and all moving objects in Intertropical Convergence Zone, or ITCZ, for the Northern Hemisphere are deflected to the short. right (clockwise motion), and in the Southern Hemisphere to the left (counterclockwise The continuous column of rising air at the equator motion). forces the air mass above to spread north and south  This deflection in the pattern of air flow is the toward the poles. Coriolis effect, named after the 19thcentury French mathematician G. C. Coriolis, who first As air masses move poleward, they cool, become analyzed the phenomenon. heavier (more dense), and sink In addition to the deflection resulting from the Coriolis effect, air that moves poleward is subject to longitudinal compression, that is, poleward-moving 13 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 air is forced into a smaller space, and the density of These systematic patterns of water movement are the air increases. called currents. These factors prevent a direct, simple flow of air Each ocean is dominated by two great circular water from the equator to the poles motions, or gyres. Within each gyre, the ocean current moves Instead, they create a series of belts of prevailing clockwise in the Northern Hemisphere and winds, named for the direction they come from. counterclockwise in the Southern Hemisphere These belts break the simple flow of surface air toward the equator and they flow aloft to the poles into a series of six cells, three in each hemisphere. They produce areas of low and high pressure as air masses ascend from and descend toward the surface, respectively Along the equator, trade winds push warm surface waters westward. When these waters encounter the eastern margins of Surface Winds and Earth’s Rotation Create continents, they split into north- and south-flowing Ocean currents along the coasts, forming north and south Currents gyres. The global pattern of prevailing winds plays a crucial As the currents move farther from the equator, the role in determining major patterns of surface water water cools. flow in Earth’s oceans. 14 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 Eventually, they encounter the westerly winds at higher latitudes (30–60° N and 30–60° S), which When air comes into contact with liquid water, produce eastward-moving currents. water molecules are freely exchanged between the air and the water’s surface. When these eastward-moving currents encounter the western margins of the continents, they form cool When the evaporation rate equals the condensation currents that flow along the coastline toward the rate, the air is said to be saturated equator. In the air, water vapor acts as an independent gas Just north of the Antarctic continent, ocean waters that has weight and exerts pressure. circulate unimpeded around the globe. The amount of pressure that water vapor exerts independent of the pressure of dry air is called vapor pressure [defined in units of pascals (Pa)]. Temperature influences the moisture content of air The saturation vapor pressure, also known as the water vapor capacity of air, cannot be exceeded. Whenever matter, including water, changes from one state to another, energy is either absorbed or If the vapor pressure exceeds the released. capacity,condensation occurs and reduces the vapor pressure. Latent heat (from the Latin latens, “hidden”) - amount of energy released or absorbed (per gram) Saturation vapor pressure varies with temperature, during a change of state. increasing as air temperature increases. In going from a more ordered state (liquid) to a less The water vapor content of air at saturation is called ordered state (gas), energy is absorbed the saturation vapor pressure. While going from a less ordered to a more ordered Having a greater quantity of thermal energy to state, energy is released support evaporation, warm air has a greater capacity for water vapor than does cold air Evaporation, the transformation of water from a liquid to a gaseous state, requires 2260 joules (J) of The amount of water in a given volume of air is its energy per gram of liquid water to be converted to absolute humidity water vapor A more familiar measure of the water content of the Condensation, the transformation of water vapor to air is relative humidity, or the amount of water a liquid state, releases an equivalent amount of vapor in the air expressed as a percentage of the energy. saturation 15 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 vapor pressure increases. As a result, the dew evaporates, increasing. vapor pressure in the air. At saturation vapor pressure, the relative humidity is 100 percent. If air cools while the actual moisture content (water vapor pressure) remains constant, then relative humidity increases as the value of saturation vapor pressure declines. If the air cools to a point where the actual vapor pressure is equal to the saturation vapor pressure, moisture in the air will condense. Lesson 3: Aquatic Ecosystem This is what occurs when a warm parcel of air at the surface becomes buoyant and rises. 1. Abiotic and Biotic Factors As it rises, it cools, and as it cools, the relative Environmental factors that differentiate aquatic humidity increases. When the relative humidity ecosystems. reaches 100 percent, water vapor condenses and forms clouds. Salinity is the amount of dissolved salt in the water.  Formed by the weathering of rocks. As soon as particles of water or ice in the air  Higher salinity water is more dense. become too heavy to remain suspended, Hardness is the amount of minerals (calcium and precipitation falls. magnesium) in freshwater. Temperature measures the average kinetic energy For a given water content of a parcel of air (vapor of the water molecules. pressure), the temperature at which saturation vapor  Warmest at the surface and near the equator. pressure is achieved (relative humidity is 100 percent) Availability of sunlight decreases with water depth. is called the dew point temperature. Dissolved oxygen is the amount of oxygen gas per mL of water. Think about finding dew or frost on a cool fall  Highest in cold, turbulent water. morning. As nightfall approaches, temperatures drop  Lowest in warm, stagnant water. and relative humidity rises. If cool night air pH is a measurement of the acidity or alkalinity of temperatures reach the dew point, water condenses water. and dew forms, lowering the amount of water in the air. As the sun rises, air temperature warms and the Acids - pH below 7 water vapor capacity (saturation vapor pressure) Neutral - exactly 7 16 BIO104 Ecology Bs in Biology | MOLLANEDA | 1st SEM 2024 Bases - pH above 7 Limnetic Zone (Photic)  Rainwater: 5.6 due to mixing with CO2.  The limnetic zone is an open water area too deep  Pure water.is 7 for emergent plants.  Ocean Water: 8.1 due to carbonate (CO32-) ions.  Photic: Warm and sunlit, supports phytoplankton.  Acid rain: