Sustainability of Life in Ecosystems - Integrated Sciences PDF

**Sustainability of life in ecosystems from the perspective of scientific integration.** **The first axis\ **\ **Chapter One: The Aquatic Ecosystem\ Chapter Two: The Atmosphere\ Chapter Three: Soil\ Chapter Four: the role of science in environmental sustainability.\ **\ **Chapter One: The Aquatic E...

**Sustainability of life in ecosystems from the perspective of scientific integration.** **The first axis\ **\ **Chapter One: The Aquatic Ecosystem\ Chapter Two: The Atmosphere\ Chapter Three: Soil\ Chapter Four: the role of science in environmental sustainability.\ **\ **Chapter One: The Aquatic Ecosystem\ Learning outcomes\ [After completing the study of this chapter, the student will be able to\... ]** 1. Know the hydrosphere and its relationship with other envelopes on planet Earth. 2. Explain the role of the water cycle in nature in causing various environmental changes. 3. Explain the chemical interactions in the aquatic ecosystem and their impact on water quality and the sustainability of marine life. 4. Illustrate the impact of the physical properties of water, such as specific heat, and surrounding physical factors like temperature and pressure on the distribution of living organisms and the sustainability of the aquatic ecosystem. 5. Evaluate the biological adaptations of living organisms in aquatic environments and their role in the sustainability of the ecosystem. 1. Water pollution 2. Climate changes 3. Sustainability of water resources 4. Maintaining biodiversity 5. Water Resources Management 6. Sustainability challenges in the context of population growth.\ \ **The first axis is ecosystems and the sustainability of life.\ Chemical reactions and their impact on water quality.\ ** **Get ready**\ Every time you drink a glass of water, have you thought about the chemical reactions that could occur within this vital liquid? Water is not just a transparent liquid; it is a medium in which many chemical compounds can interact, affecting the quality of water and the health of living organisms that depend on it. In this chapter, [we will explore the hydrosphere and the water cycle in nature, as well as some basic physical properties and chemical reactions that occur in water, and how these properties and reactions can affect the components of the environment.]\ \ **Learn\ **Water is characterized by its unique properties that support life, as it can dissolve many chemical substances and can exist in all three states of matter: solid, liquid, and gas, within the range of temperatures known on the Earth\'s surface. Water is essential for the continuation of life on Earth. All forms of life have a membrane that separates the living organism from its environment. Water passes from the environment into the living cell through this membrane, carrying the necessary materials for energy production and also removing waste to the outside.\ \ **\*The different layers on planet Earth.\ **The water cover distinguishes planet Earth from the other planets in the solar system and refers to water in its liquid state on the planet. Water covers about 70% of the Earth\'s surface. About 97% of this liquid water is found in oceans, seas, and saline lakes as saltwater. The remaining part represents the freshwater found in rivers, freshwater lakes, and groundwater.\ Water vapor (water in its gaseous state) is considered one of the components of the atmosphere. There is also the ice cover, which refers to the frozen water in polar regions, mountain peaks, and glaciers.\ Egypt is characterized by the diversity of its aquatic environments, which include the Nile River, the Gulf of Suez, the Gulf of Aqaba, the Red Sea, the Mediterranean Sea, and numerous saline and freshwater lakes.\ \ **\*The water cycle in nature.\ **Water exists on the surface of the Earth or nearby in a constant state of change between its three states. Water continuously moves from one place to another through various pathways, forming an almost closed system known as the water cycle in nature or the hydrological cycle. The water cycle is a system capable of physically, chemically, and biologically changing the Earth\'s surface.\ The water cycle in nature mainly includes the process of evaporation, which contributes to cloud formation, and the process of precipitation or rainfall. In addition to other processes such as biological processes that succeeded in plants, and respiration in plants and animals, there are processes of water seepage through the pores of soil and sedimentary rocks to form groundwater.\ Water vapor in clouds can chemically react with compounds present in the air, forming some acids that fall as acid rain, which contributes to the weathering of rocks.\ \ **Research activity\ **1. What are the different tools and measurements used by meteorologists to measure the annual rainfall amounts that fall on a specific area of the Earth\'s surface?\ 2. Can scientists predict future changes in a cycle on Earth?\ \ **\*The chemical composition of water.\ **Water is composed of two elements, hydrogen and oxygen, in a volume ratio of 1:2, respectively. Oxygen accounts for 88.89% of the molecular weight of water, while hydrogen represents 11.11%. The two hydrogen atoms are bonded to the oxygen atom by two covalent bonds, forming an angle of approximately 104.5 degrees between them.\ \ **\*The chemical properties of water.\ **There is no water on the surface of the Earth in its pure form, as it contains many ions and chemicals that interact with it in various ways. We will review three of the main properties of water. **1. Polarity of water\ **The oxygen atom is characterized by a higher electronegativity than the hydrogen atom, which causes the bonding electrons to be attracted towards the oxygen atom, resulting in a partial negative charge on the oxygen atom and a partial positive charge on the hydrogen atom. This phenomenon is known as the polarity of the water molecule. The polarity of water molecules leads to their association with other water molecules through what is known as hydrogen bonds, or with polar molecules of other substances, which gives water the ability to dissolve many salts and break them down into hydrated ions.\ \ The ability of water molecules to form hydrogen bonds with each other is also a fundamental reason for the high boiling point of pure water, which reaches 100 degrees Celsius under normal atmospheric pressure, compared to the boiling point of similar compounds, such as hydrogen sulfide, which is -61 degrees Celsius.\ \ **2. Hydrolysis (hydration)\ **There is a small percentage of water molecules in the form of hydrogen ions and hydroxide ions. As a result of chemical reactions with various compounds, hydrolysis of some salts present in natural waters occurs, affecting the balance of these ions, which leads to the acidity or alkalinity of the water.\ \ Practical example: When table salt is added to water, it dissociates into sodium ions and chloride ions, and the salt ions remain in the solution without bonding to the water ions, which makes the solution neutral because the concentration of hydrogen ions equals the concentration of hydroxide ions.\ In the case of sodium bicarbonate, hydrolysis occurs, leading to a decrease in the concentration of hydrogen ions and an increase in the concentration of hydroxide ions, which makes the salt solution basic. The opposite occurs when dissolving ammonium chloride salt in water, which hydrolyzes and causes a decrease in the concentration of hydroxide ions and an increase in the concentration of hydrogen ions, thus making the salt solution acidic.\ \ **3. Acid-base balance\ **The acid-base balance in water depends on the relationship between the concentration of hydrogen ions and hydroxide ions, and this relationship can be identified through the value known as the pH of the solution.\ It is a graduated scale that takes values from 0 to 14. If the concentration of hydrogen increases, the water becomes acidic, and the pH value is less than seven. If the concentration of hydroxide increases, the water becomes basic, and the pH value is greater than seven. If the concentration of ions is equal, the water is neutral, and the pH value is 7. The pH level: is a measure that expresses the acidity or alkalinity of water. Pure water has a pH of about seven, which is considered neutral. However, this number can vary in natural environments, affecting the living organisms that inhabit them.\ \ The pH value of water from different sources.\ 1. **Seawater**: The pH value of seawater generally ranges from 7.5 to 8.4, depending on the region where the sea is located and the surrounding environmental factors.\ 2. Freshwater (rivers and lakes): The pH value varies and typically ranges naturally between 6.5 to 8.5.\ 3. **Distilled water**: Its pH value is about seven, as it is free from most impurities and ions that contribute to the acidity or alkalinity of other natural water sources.\ 4. **Groundwater**: The pH level of groundwater varies from one area to another depending on several factors, the most important of which is the geological composition of the region. The groundwater can either be neutral or alkaline, and its environmental value varies due to the presence of calcium carbonate or magnesium carbonate rocks.\ 5. The pH level of rainwater is generally slightly acidic, ranging from 4.5 to 5, due to the presence of excess carbon dioxide and other acidic gases in the water droplets. These values can vary depending on different environmental factors and human activities in that area, which can affect the pH level during cloud formation or rainfall.\ \ Scientific activity\ Measuring the difference in pH levels in various water samples.\ To measure the pH value of different water samples (seawater).River water, spring water) You can conduct the following experiment:\ The required materials.\ 1. Water samples\ 2. pH meter or pH test strips\ 3. Sample cups\ 4. Distilled water for calibration.\ 5. Leg turning.\ Conducting the experiment.\ 1. Calibration: Please calibrate the pH meter according to the manufacturer\'s instructions using distilled water.\ 2. Sample preparation: Number the cups according to the type of water sample and place a small amount of that type in each one.\ 3. Test: Immerse the electrode of the calibrated pH meter in each sample and record the reading once it stabilizes.\ 4. Measuring with test strips: In the case of using test strips, dip the strip into each sample for a few seconds, then compare its color to the attached chart to determine the approximate pH value.\ \ Research activity\ Here, with a group of your colleagues, conduct a research study supported by statistical data that shows the difference in pH values of clouds and rain, and the reasons for that in both.\ 1. Industrial cities\ 2. Agricultural areas\ 3. Coastal cities To mitigate the potential negative effects on water quality and the health of living organisms due to saline hydrolysis and its impacts on water chemistry, it is important to closely monitor salinity levels as well as changes in ionic composition within natural water bodies.\ Proper waste disposal practices reduce the addition of harmful salts to water bodies and maintain water quality for wildlife habitats and human consumption purposes.\ \ Multiple choice questions\ 1. Which of the following represents the percentage of freshwater on the Earth\'s surface?\ 50% 3% 70% 97%\ \ Higher-order questions\ 1. Explain how changes in the pH value of river water can affect the surrounding ecosystem. It offers suggestions to improve the water quality in this river.\ 2. Design an experiment to study the effect of different chemicals on water quality, and determine how the results of this experiment can be used to preserve aquatic environments. ***2-1 Physical properties of water and their role in the distribution of living organisms*** Water has unique physical properties that distinguish it from other liquids and gases, such as: - The decrease in its density when it reaches the freezing point and - The increase in its specific heat, which affects many natural phenomena and the distribution of living organisms in different environments. **Density** It is the mass of a unit volume of a substance at a certain temperature, and because the substance is made up of molecules, the density of the substance depends on the mass of the molecules and the distances between them. In the case of pure water, the mass of 1 cm of it at a temperature of 40 is equal to 18. That is, the density of water at 40 is equal to g/cm, which is equivalent to 1000 in the international unit of density. As the temperature of water decreases from 40 to its freezing point, its density decreases, as shown in the opposite figure. The ratio between the density of a certain substance and the density of pure water at the same temperature is known as the relative density of the substance. The density or relative density of liquids is measured by a hydrometer, which is a hollow, sealed glass reservoir with a wider bottom for buoyancy, in which there are lead (or mercury) balls that help in vertical balancing. Its reservoir is connected to a long glass stem with a small diameter graduated in density units so that the lower graduation indicates the highest density measured by the hydrometer and the upper graduation indicates the lowest density measured by the hydrometer in the opposite figure. **Scientific activity** **Measuring the density of different water samples** Use a hydrometer to determine the density of water from different sources (sea / river / canal / pond /Lake/underground). Discuss how a hydrometer can be used to predict the presence of dissolved contaminants in a water sample. **Water density and ocean currents** The density of water in the oceans is affected by - The pressure inside it - The amount of salt dissolved in it - Its temperature. As the pressure increases with increasing depth, the water molecules get closer together, and thus its density increases. Density is also affected by the amount of salt dissolved (salinity) in the water. The higher the salinity of the water, the higher the density of the water. The normal salinity of ocean water is 35 g/L of water, (or the equivalent of two teaspoons per cup of water). Finally, the temperature of the water affects its density. As the temperature of the water decreases (until it reaches 4[℃]{.math.inline}, the molecules get closer to each other, and thus occupy less volume and its density increases. Differences in water density are one of the causes of ocean currents. Ocean currents transport: - Heat and salt from the tropics to the poles, - Nutrients from the depths of the ocean to the surface - Fresh water flowing from rivers or melting glaciers to different places on its journey around the world. **Water density in polar regions** The density of water changes as its temperature changes, as the volume of a liquid generally increases with increasing temperature and decreases with decreasing temperature. Water is an exception to this rule. When the temperature of pure water rises from (C) to (4), the water shrinks and thus its density increases. The density of water reaches its highest value, equal to 1000 kg/m3, at 4, and water expands as the temperature rises above 40. Thus, its density decreases. This helps explain why a lake in the polar regions starts at the surface rather than the bottom. When the air temperature is between 4 and OC, the surface water of the lake expands, becoming less dense than the water below it. Eventually the surface water freezes and the ice remains on the surface since the density of ice is less than the density of water while the water near the bottom remains at 4C. If this were not the case, fish and other marine life would not survive. **[Experiment]** **[Effect of density difference on water movement]** Make ice cubes by adding food coloring to the water before it freezes and becomes an ice cube, to help facilitate the observation of the melting process of cubes and the direction of water movement after it melts. Place one cube of ice in a quantity of fresh water, and another in an equal quantity of salt water in which the concentration of the salt is equivalent to the concentration of salt found in ocean at room temperature. In which case will the ice cube melt faster? What are your observations on the movement of water resulting from the melting of each cube? This is what happens in the ocean. If fresh water from melting icebergs enters the ocean, this fresh water spreads on the surface of the ocean and will not sink. If this fresh water freezes, it forms an insulator between the deep regions of the ocean and the cold air is higher. Check your understanding 1. Analyze the graph below and conclude what happens to the density of water with temperature change. 2. Give an example of how changes in temperature and density of water affect living organisms in the aquatic environment. **Oxygen and carbon dioxide in the aquatic environment** Naturally, rivers and seas contain sufficient levels of oxygen and carbon dioxide to sustain marine life, including plants, marine animals, fish, and microorganisms such as bacteria and algae. Oxygen is present in small quantities in water and the main source of oxygen is the atmosphere. In addition to the role played by phytoplankton, algae and aquatic plants through photosynthesis in producing oxygen in the water. In the seas and oceans, more oxygen dissolves in the water as a result of waves and turbulence within the ocean. Which can increase the exchange of gases between the atmosphere and water. In general, these natural processes provide marine creatures with the dissolved oxygen they need to survive. ***Solubility of gases in water*** The concentration of oxygen gas in the air is about 500 times higher than that of carbon dioxide gas, but oxygen gas is about 50 times less soluble in water, and the solubility of the gases in salty ocean water is about 20-30% less than their solubility in water. In general, the solubility of the two gases is lower at higher temperatures. As the temperature rises, the percentage of carbon dioxide dissolved in water decreases at a greater rate than the percentage of oxygen in water. The graph shows the relationship between the solubility of oxygen and carbon dioxide in fresh water at different temperatures under the natural composition of the atmosphere. ***Effect of increasing the percentage of dissolved oxygen in water:*** 1. Enhances respiration:\ Organisms depend on dissolved oxygen in the water for respiration. Increasing the amount of oxygen in the water improves their ability to breathe. 2. Improves metabolism:\ High levels of dissolved oxygen can support the metabolic processes of aquatic organisms and promote growth. 3. Increased activity:\ Adequate levels of dissolved oxygen stimulate the organisms to more activity in tourism, hunting and reproduction. 4. Maintaining the balance of the ecosystem:\ The healthy balance of dissolved oxygen in the water is the importance of maintaining a stable Beni Mani ecosystem by supporting a diverse population of fish, invertebrates and plants. Research activity Research various sources about the factors that lead to a decrease in the percentage of oxygen gas in water, and the effects of its decrease. ***Sources of carbon dioxide in the aquatic environment:*** - The atmosphere is the main source of carbon dioxide (CO~2~) in water. CO~2~ is exchanged between the atmosphere and water. - Marine organisms produce carbon dioxide, which dissolves in the surrounding water as one of the wastes resulting from metabolic processes. - Human activities such as industrial pollution and the decomposition of organic matter carried by agricultural wastewater. ***The effect of increasing the percentage of carbon dioxide in water on aquatic organisms:*** Increasing the percentage of carbon dioxide (CO~2~) in water can have several negative effects on marine organisms: 1. Acidification:\ When carbon dioxide levels are high in the atmosphere, it can dissolve in greater concentration in water, resulting in increased carbonic acid and a lower pH value of the water. This acidification can be harmful to many species of aquatic organisms, especially those with sensitive life stages such as the egg and larval stages. 2. Impaired respiration:\ High levels of carbon dioxide can lead to decreased the percentage of dissolved oxygen in water, which is necessary for the respiration of aquatic organisms. 3. Reducing calcification:\ Many marine organisms, such as corals, mollusks, and some types of plankton, rely on calcium carbonate to form their skeletons. This is a solid substance that is poorly soluble in water. Increased carbon dioxide levels convert it to calcium bicarbonate, which dissolves in water, hindering the ability of these organisms to build or maintain their skeletons. ***The effect of carbon dioxide deficiency in water on aquatic organisms:*** 1. Photosynthesis reduction:\ Aquatic plants and algae need carbon dioxide to carry out photosynthesis. Low carbon dioxide may lead to a reduction of its ability to produce energy, which affects the overall productivity of the environmental system. 2. Impact on food chains:\ Changes in the level of carbon dioxide in the water can affect on productive organisms such as phytoplankton and algae, thus affecting organisms at higher levels of food chains. 3. pH imbalance:\ Low CO~2~ concentrations may lead to an increase in pH, negatively affecting sensitive species adapted to a range of certain pH value. Biological adaptations of living organisms in the aquatic environment. prepare In the world of marine creatures, every living thing has a set of adaptations that help it survive in its marine environment, whether it is in deep oceans or shallow lakes. How do fish adapt to temperature changes? How can organisms survive in salty or low-oxygen water environments? In this lesson, we will explore these physiological, behavioral, and structural adaptations that Allows aquatic organisms to live in a variety of intermediate conditions. to learn physiological (functional) adaptation Organisms in the marine environment develop special physiological adaptations that enable them to survive in their environment, i.e. adaptations or modifications in the way they perform their natural functions. For example, some fish that live in the depths of the oceans have special abilities to regulate breathing in conditions of low oxygen and to adapt to the high water pressure at depths. Deep-sea fish have strong and durable arteries and veins that can withstand high pressure. They also have the ability to effectively regulate blood pressure to remain in proportion to external pressure. A famous example of these fish is the electric eel, which lives at depths of thousands of meters, where oxygen levels are extremely low. These fish have evolved very large gills, with very fine blood capillaries that increase the efficiency of extracting the little oxygen present in the water. In addition, they can slow down their metabolism to reduce their oxygen needs. Osmosis and osmotic pressure Osmosis is the phenomenon of the transfer or diffusion of water from a dilute solution to a concentrated solution through a semi-permeable membrane separating the two solutions, as shown in the figure. Osmotic pressure is the pressure resulting from a difference in the concentration of a solution as a result of the presence of a substance. Semi-executed dinner run counting the convict Osmotic water flow The osmotic pressure that leads to the diffusion of water by osmosis. The solution with a higher concentration has a higher osmotic pressure than the solution with a lower concentration, which makes it pull water from the solution with a lower concentration, as shown in the figure. Scientific activity Tools: Sugar solution, thistle funnel, Sullivan paper, glass cup with rubber band, step holder. Install the cellophane paper on. suppress the hyena Final level Solomon\'s paper End of the experiment, beginning of the navy Seal the funnel opening tightly with a rubber band. Osmosis demonstration experiment First level of solution Fill the funnel with the sugar solution, then immerse it in the beaker filled with water and fix it. plumb. Mark the stem of the funnel at the level of the solution. Leave the device for a sufficient period of time and observe what happens, recording your observations. You notice the sugar solution level rising in the funnel stem, increasing its volume due to it drawing water from the cup by osmosis, because the sugar concentration in it is higher than the sugar concentration in the water in the glass cup. Freshwater organisms adapt physiologically to low osmotic pressure. The previous experiment explained what could happen to an organism living in fresh water as a result of the osmotic pressure of the water being lower than the osmotic pressure of the solutions in the bodies of those organisms. 0 In this case, the bodies of these organisms draw large amounts of water, which leads to their explosion and death. How do these organisms adapt to the characteristics of the freshwater environment? Boglina contracted gap His dawn is contracted contracted gap Paramecium Unicellular organisms, such as amoeba, paramecium, and euglena, have a cellular structure or organelle called a contractile vacuole, in which the cell collects excess water and then pushes it toward the cell membrane to empty the water inside it to the outside of the cell, as shown in the figure. As for multicellular organisms such as fish, they get rid of excess water that enters the body through the skin, mouth and gills through the kidneys in the form of diluted urine. The kidneys in fish are located in the abdominal cavity on both sides of the spine as shown in the figure. Kidneys in fish college gills Fish that live in salt water need to swallow large amounts of water to compensate for the loss of water from their bodies through osmosis. Their source for this is highly saline seawater. They then excrete the excess salts through the kidneys and specialized cells in the gills. Among the physiological adaptations to confront the high salinity of water in the oceans and seas, you find that sharks maintain the balance of water and salts inside their bodies by a special mechanism to control the level of urea in their blood, as urea is a nitrogenous compound secreted in the urine of many animals) and is disposed of. Sharks maintain a high concentration of urea in their blood, which increases pressure. Its osmotic pressure is close to the osmotic pressure of the surrounding water. This helps reduce water loss from its body to the surrounding high-salinity environment. Behavioral adaptations Behavioral adaptations include specific actions or behaviors that organisms perform to avoid harsh conditions or to make better use of available resources. For example, some fish migrate between waters Fresh and salty for reproduction and survival.. Salmon are born in fresh water, then move to the sea where they spend most of their adult life, before returning to the rivers again to reproduce. When the salmon eggs hatch, their young spend the period The first stage of their life is in fresh water. During this stage, the young adapt to the fresh water environment. Upon reaching a certain size, the fish undergo a biological process known as \"osmotic adaptation\" which is followed by the transition to salt water in the sea. When the salmon reach sexual maturity, they begin to return again. salmon migration Others go to the rivers where they were born to breed. The ability of salmon to move between different environments is due to their ability to make complex physiological adaptations. For example, their circulatory and respiratory systems adapt to changes in The degree of salinity and the amount of oxygen differ in fresh and salt water. Structural adaptations Structural adaptations include changes in the physical structure of organisms that help them survive in their environments. For example, fish that live in the deep ocean have very large eyes to be able to see in the dark, and their bodies are ice fish Compressed to withstand the very high pressure in deep water. An example of a fish that is compressed at depth is the ice fish, which lives in the cold southern oceans, at depths of up to.to 2000 meters General structural adaptations of fish The streamlined body that reduces water resistance, the movement of the fish, and the gills that enable it to extract oxygen dissolved in the water. Its body is covered with scales and mucus to be waterproof and to reduce water resistance to its movement when swimming. The fins are also the organs of movement. Bony fish have a swim bladder, or swim sac, that helps them float in the water. Gas exchange and cellular respiration Gas exchange is the process by which an organism obtains oxygen from the air or the surrounding environment. And getting rid of carbon dioxide. As for cellular respiration, it is a vital process carried out by a living organism that breaks down the bonds found in food molecules, especially glucose, to obtain stored energy. Unicellular organisms such as amoeba obtain oxygen and get rid of carbon dioxide through the cell membrane by diffusion. activity Analysis of the relationship between biological adaptations and the aquatic environment Search the Internet for biological adaptations found in lionfish and colorful octopus. lionfish Colorful Octopus Check your understanding Choose the correct answer: Which of the following is a physiological change in ocean fish? a\) Compressed body c\) Increased blood pressure With strong arteries d\) Large gills Which of the following adaptations enables deep-sea fish to cope with a lack of oxygen? \(1) Slowing down the metabolic rate b compact body Increased salt concentration in cells d\) Strong blood vessels What is the type of osmotic adaptation in salmon? 1\) Behavioral adaptation b\) Physiological adaptation I have a complex air conditioner D\) Physiological and structural adaptation Which of the following is a similarity between amoebas and fish? \(1) Cellular respiration b gas exchange member Body complexity came d\) Osmoregulation methods Which of the following helps reduce water resistance to fish movement in the water? 1\) Peels only c mucus and streamlined body Only with mucus Streamlined body, mucus and scales 6\. Physiological adaptations require structural adaptations. Give one example of: that. What challenges do deep-sea fish face and how do they adapt to them structurally? What is the effect of fresh water on the osmotic pressure of freshwater organisms and how? How do those creatures deal with that effect?