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REVIEWER | SCIENCE Abiotic Components CHAPTER 7 ECOSYSTEM ▪ Abiotic component of ecosystem refers to the physical environm...

REVIEWER | SCIENCE Abiotic Components CHAPTER 7 ECOSYSTEM ▪ Abiotic component of ecosystem refers to the physical environment Ecosystem and its several interacting variables. A biological community of Lithosphere interacting organisms and their Hydrosphere physical environment Atmosphere A.G. Tansley ( 1935) - who stated The radiant solar the following words, “ the more energy fundamental conception is the whole system. Biotic and Abiotic of an Ecosystem The term “ ecosystem” was used in a publication by British ecologist Arthur Tansley. Tansley devised the concept to draw attention to the importance of transfer of materials between organisms and their environment. Flow of Energy and Biogeochemical cycling - these Food Chain two processes bind the organisms to their environment and the Food chain is a linear network of complex network is termed as the links in a food web starting from ecosystem. producer organisms ( such as grass or trees) which use radiation from the sun Biotic Components to make their food) and ending at apex Biotic component is comprised predator species ( like killer whales), the living organisms. detritivores ( like earthworms), or Community’ is essentially treated decomposer species ( such as fungi or as a biotic component of the bacteria). ecosystem. ▪ Food chains were first introduced Autotrophs can produce their by the African-Arab scientist and own food. They are the green philosopher Al-Jahiz in the 9th plants with chlorophyll and century and later popularized in certain types of bacteria- abook published In 1927 by chemosynthetic and Charles Elton, which also photosynthetic. introduced the food web Heterotrophs depend directly or concept. indirectly on the autotrophs for ▪ All organisms in a food chain, their food. It is also called except the first organisms, are consumer. Photographs and consumers. Osmotrophs. Phagatrophs take food from Types of Food Chain outside and digest it inside their Grazing food chain bodies. Detritus food chain Osmotrophs are those organisms Parasitic food chain who secrete digestive enzaymes to break down the food into Grazing Food Chain simpler substances and then absorb the digested food. ▪ Grazing food chain. The primary producers are the living green  REVIEWER | SCIENCE plants which are grazed on by of what-eats-what in an ecological grazing animals. It is found in community. aquatic and grassland ecosystem. ▪ Another name for food web is a ▪ These are directly dependent consumer-resource system. upon solar radiations as the ▪ Food web is a simplified primary source of energy and the illustration of the various methods producers ( green plants) of feeding that links an ecosystem synthesize their plant biomass by into a unified system of exchange. the process of photosynthesis. ▪ Charles Elton pioneered the Producers from the first trophic concept of food cycles, food level. chains, and food size in his ▪ Herbivores or primary consumers classical 1927 book “Animal eat upon the producers and from Ecology”, Elton’s ‘food cycle’ was the second trophic level. replaced by ‘food web’. ▪ Grazing food chains are longer ▪ John Bruckner (1978) described food chains and they always end nature as “one continued web of at decomposer level. life” Detritus Food Chain Trophic Levels ▪ Detritus food chain: This type of ▪ The trophic level of an organism food chain starts from dead is the position it occupies in a organic matter and so it is less food chain. dependent on solar energy. The ▪ Trophic derives from the Greek dead organic matter is broken word (trophe) referring to food down into simple nutrients by or feeding. microorganisms like fungi and ▪ Trophic levels are numbered bacteria. This type of food chain is subsequently according to how found in forest ecosystem. far the organism is along the food ▪ Primary source of energy is dead chain. organic matter called ‘detritus’ which are fallen leaves, plant parts or dead animal ecosystem. Level 1. Plants and algae make their ▪ Detritus food chain are generally own food and are called primary shorter than grazing food chains. producers. Parasitic Food Chain Level 2. Herbivores eat plants and are called primary consumers. ▪ Parasitic food chain: In this type of food chain either the producer Level 3. Carnivores that eat herbivores or the consumer is parasitized and are called secondary consumers. therefore the food passes to the smaller organism. The energy Level 4. Carnivores that eat other transfer through this kind of food carnivores are called tertiary chain is not significant. consumers. Level 5. Apex predators that have no predators are the top of the food chain. Food Web ▪ Food web (or food cycle) is the natural interconnection of food Types of Eater chains and generally a graphical ▪ Herbivores representation (usually an image) ▪ Omnivores ▪ Carnivores  REVIEWER | SCIENCE Herbivores are animals whose primary an ecosystem. The bottom level food source is plant-based. Examples of illustrates species which act as producers, herbivores include vertebrates like deer, harnessing energy from abiotic sources. koalas, and some birds species, as well as Each subsequent level illustrates a level invertebrates such as crickets and of consumer, each of which receives caterpillars. energy by consuming the group below it. Omnivores are animals that eat both Types of Ecological pyramids plant-and animal-derived food. ▪ Number pyramid Carnivores are animals that eat other ▪ Biomas pyramid animals. The word carnivore is derived ▪ Energy pyramid from Latin and means “meat eater”. Number pyramid Types of Decomposers ▪ It depicts the number of ▪ Decomposers individual organisms at ▪ Scavengers different trophic levels of food ▪ Detrivores chain. This pyramid was advanced by Charles Elton (1927), who pointed out the Decomposers great difference in the number of the organisms involved in ▪ Produce enzymes that digest the each step of the food chain. dead material, which provides Successive links of trophic nutrients for organisms in the soil. structure decrease rapidly in Scavengers number until there are very few carnivores at the top. ▪ This group feeds on dead animals, ▪ The pyramid of numbers rather than just decomposing ignore the biomass of them in the soil. organisms and it also does not Detrivores indicate the energy transferred or the use of energy by the ▪ Plants or animals that feed on groups involved. The lake detritus, or decomposing organic ecosystem provides a typical matter example of pyramid of number. Biomass Pyramid ▪ The biomass of the members of the food chain present at any one time forms the Decomposer Scavengers Detrivores pyramid of the biomass. s Pyramid of biomass indicates decrease of biomass in each tropical level from base to Ecological pyramid apex. An ecological pyramid is a ▪ For example, the total biomass graphical model that illustrates the flow of the producers ingested by energy through different forms of life in herbivores is more than the  REVIEWER | SCIENCE total biomass of the herbivores Bioenergetics is a broad discipline of in an ecosystem. Likewise, the biochemistry that focuses on energy total biomass of the primary transformations within living carnivores (or secondary organisms, and the efficiency of consumer) will be less man the energy transfers between different herbivores and so on. organisms. All living things use energy, but they use it on different Energy Pyramid ways. Consider plants and animals. When production is considered in ▪ The biology of energy terms of energy, the pyramid transformations and energy indicates not only the amount of exchanges (as in photosynthesis) energy flow at each level, but within and between living things more important, the actual role and their environment. the various organisms is needed as it flows upwards to support the next tropic level. The pyramid is constructed according to the rate at which food material (in the form of energy) passes through the food chain. Some organisms may have a small biomass, but the total energy they assimilate and pass on, may be considerably greater than that of organisms with a much larger biomass. Energy pyramids are always slopping because less energy is transferred from each level than was paid into it. In case such as in open water communities the producers have less bulk than consumers but the energy they store and pass on must be greater than that of the next level. Energy Flow in the Ecosystem Bioenergetics ▪ Study of energy relationships and energy transformation in living organisms  REVIEWER | SCIENCE CHAPTER 8 Primary Production ECOLOGICAL SUCCESSION Primary production is when plants make their own food and use that food to live and grow. These plants do ECOLOGICAL SUCCESSION not depend on other plants, animals, or insects for their food. They can make Ecological succession is the their own with help from the sun, water, gradual process by which ecosystems and air. change and develop over time. Nothing remains the same and habitats are Common primary producers in a constantly changing. schoolyard ecosystem are: Types of Succession grass dandelion Primary succession is the series of milkweed community changes which occur on an oxalis entirely new habitat which has never clover been colonized before. oxeye daisy Norway maple Examples of such habitats would red oak include newly exposed or deposited surfaces, such as landslips, volcanic lava How Do Primary PRODUCERS Make and debris, elevated sand banks and Their Own Food? dunes, quarried rock facers. Primary producers like plants Secondary succession is the series of make their own food by doing something community changes which take place on called photosynthesis. a previously colonized, but disturbed or How does photosynthesis work? damaged habitat. Leaves of plants absorb lights Examples include areas which from the sun have been cleared of existing vegetation Leaves of plants also absorb the (such as after tree-felling in a woodland) air that people breathe out, called and destructive events such as fires. carbon dioxide Secondary succession is usually much Leaves of plants also absorb of quicker than primary succession for the water. They can get water from following reasons: falling rain or they can get it out of the ground with their roots. ▪ There is already an existing seed Leaves of plants use light from the bank of suitable plants in the soil. sun to turn the air people breathe ▪ Root systems undisturbed in the out and water into glucose and soil, stumps and other plant parts oxygen. Glucose is a type of sugar from previously existing plants that plants use for food helps can rapidly regenerate. them grow. Oxygen is the gas that The fertility and structure of the soil has people breathe in. so not only do also already been substantially modified plants make their own food, but by previous organisms to make it more they make the air that we breathe suitable for growth and colonization. in! In other words, photosynthesis is: sunlight+ air people breathe out + water = plant food + air people breathe in  REVIEWER | SCIENCE Secondary Production CHAPTER 9 Secondary production is the POPULATION assimilation of organic material and building of tissue by heterotrophs, and Population is a collective group of may involve animals eating plants, organisms of the species living in the animals eating other animals, or same place at the same time. microorganisms to obtain the resources (material, energy, nutrients) needed for The term "population” is interpreted producing biomass. differently in various sciences: Mechanism of Succession In human demography a It is process of interaction that population is a set of humans in a contributes to successional change; it is a “proximate cause” of vegetation given area. change. In genetics a population is a group of interbreeding individuals Elements Mechanisms of Successional of the same species, which is (1916) isolated from other groups. Nudation - removal of vegetation In ecology a population is a group by disturbance of individuals of the same species Migration – arrival of the plants to the available site inhabiting the same area. Ecesis – establishment of plants (from seed and vegetative Measurement of population reproduction) Competition – interaction of the The most basic (though not plants which may eliminate some necessarily easiest or most species Reaction – modification of the accurate) way to measure site by the plants in a way that population is simply to count guides or drives succession everyone. This is known as a census and is usually undertaken Climax State/ Climax Community by government officials. Census Is a holistic term that expressed a also has trouble collecting biological community of plants, animals, and fungi which through the process of information on rare populations. ecological succession the development A rare population is one that is of vegetation in an area over time, had small or not reflected in standard reached a steady state. It reached the stable stage. census data. A full census is sometimes known as complete enumeration which means that every single person is counted either through face-to- face interviews or through  REVIEWER | SCIENCE questionnaire. There are no light. Birds may be denied access to the estimates. nest site due to limited space. Human population South Europe- Most density populated nation In demographics, the world population is the total number of Mongolia- Least density the humans currently living. As of Two types of Density August 2016, it was estimated at 7.4 billion. The United Nations ▪ Crude density → Is a number of biomass per estimates it will further increase to unit total space. 11.2 billion in the year 2100. ▪ Specific density The highest population growth → (Or Ecological density) is rates - global population increases the number or biomass per above 1.8% per year - occurred unit of habitat. between 1955-1975 peaking to 2.06% between 1965-1970. Population Dynamic The growth rate has declined to Population dynamics is the branch 1.18% between 2010- 2015 and is of life sciences that studies the projected to decline to 0.13 by the size and age composition of year 2100. population as dynamical systems, The global population is expected and the biological and to reach between 8.3 and 10.9 environmental processes driving. billion by 2050. UN Population Division Population affected by three dynamic population projections for the rate functions. year 2150 range 24.8 billion. ▪ Nationality or Birthrate Attributes of Population ▪ Population growth rate ▪ Morality Density Natality or Birthrate Age Distribution Biotic Potential Natality- is the greatest factor that influences population increase. It is the What is Density? inherent ability of population to increase. Density is the number of individual per Often recruitment, which means unit of space. Individuals are affected by reaching a certain size or density. Terezin crowded areas may die reproductive stage. Usually refers because of lack of water, nutrients, and  REVIEWER | SCIENCE to the age a fish can be caught and Difference between Pre reproductive counted in nets. period, Productive period, Post reproductive period Two types of Natality ▪ Pre reproductive is before you can ▪ Maximum Natality -is the reproduce reproductive is while absolute or theoretical maximum you can reproduce post production of new individual reproductive is after you can under ideal condition. reproduce ▪ Ecological Natality- is the population increase under actual Age Pyramid or environmental condition Age pyramid is a special type of bar chart Population growth rate showing the age and sex of the population Population growth rate, which measures the growth of individuals in size and Three types: length. More important in fisheries, ▪ Broad base (large percentage of where population is often measured in young individuals) biomass. ▪ Bell-shaped polygon (moderate Mortality proportion of young to old) ▪ Um-shaped figure (low Morality is usually expressed as percentage of young individuals) the probability of dying. ▪ Biotic potentials the inherit Two types property or an organisms to ▪ Minimum Mortality- is the loss reproduce, to survive or to of individual under ideal increase in number. condition. ▪ When a stable age distribution ▪ Ecological Morality- is the loss exists. the specific growth rate is of individual under given called intrinsic rate of natural environmental condition. increase. What is Age Distribution? Why population affects the balance eco system? Population can be divided into three ecological periods according to ▪ Ecological balance is important Bodenheimer: for the continued survival and existence of organisms as well as ▪ Pre reproductive (juvenile period) the stability of the environment. ▪ Reproductive The natural balance in the ▪ Post reproductive  REVIEWER | SCIENCE ecosystem, which must be is low at first then accelerates and slow maintained, may be disturbed as a again, then levels of as the carrying result of natural hazards, the capacity of the environment is reached. unexpected death of a particular Exponential growth species. man-made causes or the introduction of new species to the b. Exponential growth- is a ecosystem. pattern of growth wherein the variables affect population size and can be Other Attributes of Population measured either for the entire population 1.Growth Forms or per individual. a. Logistic Forms - states that as Equation: the density of population, increases G=Rn competition among its members for State: available resources. with fewer resources to share, as equal distribution of those Population growth rate= (birth of resources available. mortality increases individuals – deaths of individuals) x No. birth rate decreases or both occur. As a of Individuals result. population growth declines with 2. Population Dispersal increasing density. Eventually reaching a Population Dispersal- is the movement level which population growth ceases. of individual or dissiminules or The level is called carrying capacity. The propagates (seeds, spores, larvae, etc.) Logistic growth equation can be into or out of the population or expressed as: population area. 𝐾−𝑁 𝑀 = 𝑟 𝑚𝑎𝑠𝑠 𝑁 ( ) a. Emigration- is a way 𝐾 outward movement. States: b. Immigration- movement Population growth rate = of organism to specific (maximum net reproduction per area. individuals) x (No. of Individuals) x c. Migration- is the periodic (portion of unexploited resources) x departure or return. (carrying capacity- No. of 1. Population Distribution Individuals/carrying capacity Individual maybe distributed Sigmoid or S Shaped curve according to three patterns: When a low density population a. Clumped- is the most common shows a logistic pattern, its rate increase pattern. The three reason of this  REVIEWER | SCIENCE type of distribution are: a. the 3. Survivorship physical and chemical condition a. Concave (type III) – if mortality suitable for growth are typically is extremely high in early life as an “patchy” rather than uniform b. oyster, fish, many invertebrates some part of the habitat offer and some plants. more protections to prey b. Linear (type II) – if the organisms c. the dispersal of mortality are constant at all ages. seeds, larvae, and other (Adult and stages of birds, representatives forms of each new rodents. Reptiles and perennial generation is often limited. plants) c. Convex (type I) when b. Random Distribution- is the individual tend to live out their even spacing brought about by physiological life span and where the severe competition and there is a high degree of survival positive antagonism among the throughout life followed by heavy individuals. mortality at the end of the species life span. (humans, mammals) c. Uniform Distribution- is the even spacing brought about by the severe competition and positive antagonism among the individuals. 2. Life Tables Life tables- are created to summarize the age specific pattern of birth and death of a particular population in a particular environment. The rate of the births and death among individuals of different ages can be recorded in a life table. Cohort- the fate of a group of newborn schedules of the organisms taken as the sample for the study.  REVIEWER | SCIENCE CHAPTER 10 electricity, to heat our homes, to move our cars, and manufacture products from ENERGY candy bars to cellphones. What is energy – energy is defined as the ability to produce change or do These energy sources are called non- work, and that work can be divided into renewable because they cannot be several main tasks we easily recognize: replenished in a short period of time. Energy produces light Law of Thermodynamics Energy produces heat Thermodynamics is principally based on Energy produces motion a set of four laws which are universally Energy produces sound valid when applied to systems that fall Energy produces sound within the constraints implied by each. Energy produces growth Zeroth law of thermodynamics: If two Energy powers technology systems are each in thermal equilibrium Types of Energy with a third, they are also in thermal Solar Energy equilibrium with each other. Geothermal Energy Tidal Energy First law of thermodynamics: the Wind Energy internal energy of an isolated system is Wave Energy constant. Biomass Energy Fossil fuels (Coal, Oil and Natural Second law of thermodynamics: Heat Gas) cannot spontaneously flow from a colder Energy sources location to a hotter location. Renewable energy - Renewable energy Third law of thermodynamics: as a sources include biomass, geothermal, system approaches absolute zero, all hydropower, solar, and wind. They are processes cease and the entropy of the called renewable energy sources because system approaches a minimum value. their supplies are replenished in a short time. Day after day, the sun shines, the wind blows, and the rivers flow. We use renewable energy sources mainly to make electricity. Non-renewable energy - Non- renewable energy sources include coal, petroleum, natural gas, propane, and uranium. They are used to generate  REVIEWER | SCIENCE CHAPTER 11 ▪ Plants grow in layers (canopy receives most light) TERRESTRIAL BIOMES ▪ Shallow, wide roots since soil is so thin and poor in nutrients TERRESTRIAL BIOMES ▪ Little sun reaches the floor FOREST TROPICAL RAIN FOREST ▪ occupy approximately one-third Animal Adaptation of Earth's land area ▪ Many animals are specialists and ▪ account for over two-thirds of the require special habitat leaf area of land plants components to survive. ▪ contain about 70% of carbon ▪ Camouflage is common present in living things ▪ Many symbiotic relationships. ▪ are major casualties of ▪ Live in different levels of canopy deforestation, pollution, and industrial usage Threats to the Tropical Rainforest ▪ forest biomes are classified ▪ Humans strip the rainforests for according to numerous uses including logging and cattle characteristics, with seasonality ranching. being the most widely used ▪ Clearing for agriculture, timber and urban development TROPICAL RAIN FOREST ▪ Conversion of diverse forest to tree plantations. Earth most complex land biome. ▪ Damage from off-roads vehicles. ▪ Pollution of forest streams Location: Found near ▪ Timber and mineral extraction equator...little variation in temperatures. No distinct seasonal changes. Sustaining Tropical Forest TROPICAL RAIN FOREST A. Prevention Abiotic factors ▪ Protect the most diverse and endangered areas. ▪ high biodiversity and biomass ▪ Educate settlers about sustainable ▪ both hot and moist; agriculture and forestry. ▪ ideal for bacteria and other ▪ Subsidize only sustainable forest microorganisms; they quickly use decompose matter on the forest ▪ Certify sustainable grown timber floor allowing nutrients to be ▪ Reduce Poverty recycled. ▪ Slow population growth ▪