BIOSPHERE KEY QUESTION 1 IV. BIOSPHERE: The living organisms that have established themselves in the other three spheres A. In this module, two contrasting ecosystems should be studied to a greater depth and should incorporate information from Key Question 1,2, and 3; ideally one of these studies can be based upon an area with which the students have some personal familiarity. B. KQ1a: What are the major abiotic and biotic factors, which drive and influence the distribution of different ecosystems? a. The biotic and abiotic factors, which drive and influence the distribution of the world s major biomes b. A survey of the global system followed by a study of the distribution of the following biomes: i. Tropical rain forest 1. Abiotic Factors: water, warm climate, sunlight, humidity, poor soil composition due to millions of years of rain and weathering have washed out all the nutrients., and precipitation. There is an average of at least 60mm to 2000 mm of rainfall per year. The average temperature is 24 degrees Celsius. Typically hot and wet all year round with rainfall being both heavy and frequent. No dry season, it
rains all year. The layers of the Canopy, understory, forest floor (shrub area), and then the soil and nutrient cycling. 2. Biotic Factors: The plants and animals that inhabit the Tropical rainforest are necessary for the structure and thriving of this biome. Plants like bamboo and tropical fruit trees provide oxygen for the animals living in the tropical rainforest. Fruit eating animals, like birds and bats, spread seeds and are also pollinators. Insects, fungi and bacteria break down the plant matter and return nutrients to the soil. Predators like jaguars and snakes feed on smaller animals. ii. Monsoon rain forest 1. Abiotic Factors: The temperature, humidity, sunlight, soil, climate and precipitation. Temperatures are high all year round and the average temperature during the rainy season is 27.05 degrees Celsius, while monthly it is around 18 degrees Celsius. The monsoon rainforest usually has the highest temperatures just before the rainy season. This biome experiences a wet and dry season where in the dry season less than 60 mm of rainfall is recorded while in the wet season, up to 1000 mm of rainfall is recorded. 2. Biotic Factors: The plants and animals that inhabit the Monsoon rainforest are necessary for the structure and
thriving of this biome. Some animals include, monkeys, deer, parrots, and large cats like mountain lions. Some plants include deciduous shrubs, bromeliads, orchids, deciduous trees which shed their leaves to conserve the water they lose when the leaves fall off and mushrooms which break down plant matter and return it to the soil. iii. Tropical savannah 1. Abiotic Factors: The tropical savannah is a hot, seasonally dry grassland that have an extended dry and wet season. The average annual temperature of this biome is 25 degrees Celsius, while in the dry season it is 20 25 degrees Celsius, and in the wet season it s 25 30 degrees Celsius. The average amount of precipitation is 38 63 cm. The weather ranges from cool and dry to wet and warm in their respective seasons. In the summer, the soil is very fertile due to grazing of the large herbivores but during the dry season, the soil is infertile which causes the small grasses and shrubs to die off. There is a large abundance of water during the wet season, but scarce during the dry season. 2. Biotic Factors: The Biotic Factors in this biome would include the plants and animals the are needed to keep the Savannah alive. Most of the animals on the savanna have
long legs or wings to be able to go on long migrations. Some animals that inhabit the biome are the Wild dog, hyena, lion, cheetah and caracal, all preying on smaller animals to survive. Some plants that inhabit the environment would be Star grass, Umbrella Thorn Acacia, and Bermuda Grass, which provides food for the various herbivores that can help the soil became fertile. Plants in the savanna are highly specialized to grow in the the environment due to long periods of drought and they have long taproots that can reach the deep water table and thick bark to resist fires and store water. iv. Desert 1. Abiotic Factors: Hot area of land with very little moisture in the air. The dessert has an average rainfall of 25.2 centimeters a year. Average temperature during the day is about 30 degrees Celsius and at night it is 4 degrees celsius. Natural deserts occur where moisture is slim with the exceptions such as the Namib Desert in Africa where coastal fog deserts occur because of cold oceanic currents. Fog deserts are types of deserts where fog drip supplies the majority of moisture needed by animal and plant life.
2. Biotic Factors: The biodiversity of deserts is much lower than that of other biomes, as the harsh conditions only allow for the most adaptable plants and animals to survive. Producers of this biome are cacti, turpentine bushes, prickly pears. Primary and secondary consumers are rabbits, and then rattlesnakes. Plant in this biome have similar characteristics of being able to retain water for long dry periods and most animals only come out after the hot sun has set to prey. v. Temperate deciduous 1. Abiotic Factors: Located usually in the Eastern US, Canada, Europe and experiences all four seasons. There are approximately 77 153 cm of rain per year. The temperature ranges per season which allows there to be constant plant litter and decomposition on the ground. There is constant moisture but it is enough to allow greenery rather than a humid climate. Rich soil which leads to large amounts of foliage as well as animal life. 2. Biotic Factors: Deciduous trees drop their leave and go into dormancy into the winter. The trees dropping their leaves allows rodents to survive using the shed leaves as shelter or source of nutrition. Types of plants that live in this biome are lichen, moss, ferns, and hardwood trees like oak. If these
plants were not able to shed some of their foliage to conserve water they would not be able to survive the cold winter. Animals that live in this bios[here are hawks, white tailed deer, and raccoons. These animals have the ability to camouflage one way or another to their surrounding environment, without it they would not survive being pred on. vi. High latitude tundra 1. Abiotic Factors: Usually in Eastern US, Canada, Europe. Experiences all four seasons despite being very brief. 15 20 centimeters of rain as an average per year. The average temperature is 10 degrees warmer. Often compared to a desert because of the little biodiversity and varying temperatures. 2. Biotic Factors: Low amounts of biomass due to the permafrost. Nutrients never recycle. Some animals that live in this biome are bees, killer whale, and a red fox. Some plants that grow in this area are caribou moss and lichen. c. Photosynthesis: i. Its requirements and process 1. Photosynthesis requires an abundance of sunlight, water, and carbon dioxide. Photosynthesis is a process used by plants and other organisms to convert light energy, normally
from the sun into chemical energy that can be later released to fuel the organisms activities. Photosynthesis takes place in the leaves of plants which are made up of very small cells called chloroplasts and those chloroplasts contain a green chemical called chlorophyll that gives the plant its green color. The chlorophyll and other pigments absorb energy from the sunlight and then it is transferred to the photosystems responsible for photosynthesis. Water is then used to provide electrons and hydrogen ions but also produces oxygen which is then released from the leaves into the atmosphere. Hydrogen and carbon dioxide are then used to form glucose or food for the plants. Some of the glucose is used to provide energy for the growth and development of plants while the rest is stored in leaves, roots or fruits for later use by plants. ii. Photosynthesis and different wavelengths 1. The picture below shows the rate of photosynthesis to the wavelength of light being received by plants. The pigment molecules in plants absorb the boob energy of light well enough to convert it into energy for the plant. The graph below shows that for green plants most photosynthetic activity takes place in the orange and blue lights since these
are the colors that are most able to be absorbed by the main chlorophylls in the plant. The activity is lowest in green light because the green light is not able to be absorbed well enough by the pigments. The wavelengths of light dat boi are able to be absorbed easily by the photosynthetic pigments cause higher levels of photosynthesis. iii. The influence of light intensity and rainfall on plant productivity 1..A higher light intensity means that more photons are reaching the leaves on the plant. As the light intensity increases, the rate of photosynthesis will generally increase as well. Given that the other things needed for photosynthesis (water & carbon dioxide), the rate of photosynthesis will be higher the more dick light there is. However, this also means that if there is not enough water or carbon dioxide, plant productivity will not rise no matter how
much light is available. Also, once the light intensity reaches a certain level, plant productivity will no longer increase. If the light intensity gets TOO high, the rate of photosynthesis can drop as the light will start to actually damage the plant. The amount and regularity of rainfall also heavily affects plant productivity. Too much rain can saturate the soil which can ruin the chance the plant has of growing properly. Too little rain can reduce germination and result in plants that will not grow to their fullest potential. C. B KQ1b: What are the main components and characteristics of ecosystems and how are they structured? a. The characteristics of ecosystems in terms of their biotic and abiotic components: i. Soil consists of minerals or organic materials on the surface of the earth that allows for the growth of plants. Soil modifies the atmosphere by absorbing gases like methane, carbon dioxide, and water vapor. It purifies, holds, and releases water into aquifers as well as recycles nutrients back into the ecosystems. ii. Temperature can affect climate changes and cause sea levels to rise, fall, etc. It can affect the animals and plants by altering their life cycles and the makeup of the entire ecosystem as a whole.
iii. Rainfall is the result of many ecosystems having wet or dry seasons and causes humidity in the atmosphere. The wet seasons is when there is heavy rainfall compared the the dry seasons where there is little to no rain at all. Rainfall can affect the animals and plants in an ecosystem and how they adapt to survive depending on how little rainfall is received in the ecosystem. iv. Photosynthesis is a process used by plants and other organisms, that convert light energy (from the sun) into chemical energy. It is then used to fuel the organisms activity. v. Net primary productivity is the rate at which plants in a certain ecosystem produce a net use of chemical energy. It is calculated by the difference between the rate at which the plants produce the chemical energy and the rate at which the plants use the energy during respiration. vi. Succession is the observed changes in an ecological community over time. It can be observed through three types; primary (initiated change in an area that has had no ecological community to form a community), secondary (a disastrous change in a community), and seasonal (a changed caused by cyclical occurrences) D. Succession is the change in either species composition, structure, or architecture of vegetation through time. Vegetation has three important
aspects that are subject to change. Species composition includes the roster of the species. i. Biomass is the mass of living biological organisms in a given area or ecosystem at a given time (plants, animals, microorganisms) and is the total mass of organisms at a trophic level. ii. Biodiversity is the variety of living things on the planet. IE, ecosystems with high biodiversity are thriving with life and an assortment of plant and animal species. iii. Trophic levels, food chains and webs: A trophic level is the position an animal is in the food chain and shows the flow of energy from each. (producers, primary consumers, secondary consumers, tertiary consumers) Food chains show a single pathway by which energy and matter flow through an ecosystem, while food webs show multiple pathways through which energy and matter flow through an ecosystem. iv. Habitats and niches: A habitat is the natural home or environment of an animal, plant, or other organism. A niche is the place in an ecosystem that an species fits and adapts to best. b. The interaction of these components to be illustrated through relative size of the flows and stores of nutrients between vegetation, litter and soil.
i. Tropical Rain Forest 1. There is much biomass, but there is little litter since the plant life is annual. The foliage on the ground slightly prevents the little litter from reaching the soil to provide nutrients, but there is still a lot of nutrient flow. ii. Monsoon Rain Forest 1. There is a decent amount of biomass and a lot of litter, but plants on the ground keep the litter from giving much nutrients to the soil, so there is little in the soil department.
iii. Tropical Savannah 1. The biomass, litter, and soil nutrients are relatively proportional with each other, but the biomass gives a lot to the litter, which then gives slightly less to the soil. iv. Desert 1. There is very little biomass so there is not much litter, so the soil holds much of whatever is available.
v. Temperate Deciduous Forest 1. There is a good amount of biomass that provides a moderate amount to the litter which is then transferred to the soil. vi. High Latitude Tundra
1. There is very little biomass to provide soil, and once the litter is there almost none of it goes into the soil because of the presence of permafrost.