GEE 302 Intro to Ecology & Ecosystem PDF

GEE 302: PEOPLE AND THE EARTH’S ECOSYSTEM NAME: COURSE: YR&SEC: ECOLOGY CUE COLUMN: Answers to review questions, Main...

GEE 302: PEOPLE AND THE EARTH’S ECOSYSTEM NAME: COURSE: YR&SEC: ECOLOGY CUE COLUMN: Answers to review questions, Main German zoologist Ernst Haeckel coined “oekologie” ideas, Questions that connect points, Diagrams, “relation of the animal both to its organic as well as Study prompts, mind maps, KEYWORDS… its inorganic environment.” the term ecology is from Greek word “oikos” which means “household,” “home,” or “place to live.” study of the relationships between organisms and their environment. Some of the most pressing problems in human affairs—expanding populations, food scarcities, environmental pollution including global warming, extinctions of plant and animal species, and all the attendant sociological and political problems—are to a great degree ecological. -Pimm and Smith (2024) studies the interrelationships between organisms and their environment and the relationships of organisms with each other. -HUBER, GOMERČIĆ & KUSAK, (2019) PRINCIPLES OF ECOLOGY 1. Ecology and the Abiotic Environment 2. Ecological interactions among species (Biotic relationships) 3. Ecology of individual organisms 4. Ecology of populations 5. Ecology of communities 6. Ecology of ecosystems 7. Biomes 8. Biosphere Earth’s Ecosystems system that includes all organisms (biotic) and the abiotic (non- living) environment in an area, functioning together as a unit the structural and functional unit of ecology (nature) encompassing complex interaction between its biotic (living) and abiotic (non-living) components Abiotic 1. Climatic Factors Light one of the most important climatic factors is a source of energy for living organisms. Sun is the biggest source of energy on earth and constantly gives heat energy in form of solar radiations. affects various physiological activities in animals for example, reproduction, development, vision, metabolism, locomotion, etc. Heliophytes - sun loving plants Temperature another very important climatic factor affecting reproduction, metabolism, growth and development of organisms. (e.g. production of eggs, breeding season, maturation of gonads) Bergman’s rule - effect of temperature on morphology of animal’s body. has an effect on geographical distribution of plants and animals Rainfall one of the major events of water cycle on earth most important source of soil water Amount of rainfall affects distribution and type of vegetation for example, evergreen forests are found in tropical regions where heavy rains occur throughout the year Humidity Moisture present in the form of invisible vapor in the atmosphere relative humidity - amount of moisture which air can hold at saturation at the existing temperature affects life cycle of some plant groups like orchids, lichens, mosses and events such as germination of spores, etc. Atmospheric gases wind - moving air which affects lives of plants on mountains, plains and coastal regions as well as causes changes in various physical, anatomical and physiological processes of plants. Mechanical damage and uprooting of plants are one of the important physical effects of high velocity wind on plants.  GEE 302: PEOPLE AND THE EARTH’S ECOSYSTEM CUE COLUMN: Answers to review questions, Main lodging - a type of wind injury where there is flattening of ideas, Questions that connect points, Diagrams, herbaceous plants and grasses against the ground Study prompts, mind maps, KEYWORDS… fire - mostly caused by anthropogenic activities particularly in forests and changes soil fertility, litter & humus contents, pH, micro-flora & fauna, nutrient cycle. 2. Topographic Factors physical geography of any area which includes mountains, hillocks, valleys, slopes and any other surface irregularity of earth factors may sometimes create specific microclimates peculiar of any region height & direction of mountains - an important factor in determining climate; determines direction of wind flow and also affects humidity and rainfall. slope - steepness of mountain slope is responsible for difference in amount of solar radiation received and changes in soil characteristics 3. Edaphic Factors includes quality and texture of soil which affects life of plants in many ways ▪ SOIL - provides nutrients, water, a home, and a structural growing medium for organisms. Vegetation found growing on top of a soil is closely linked to the overall health of the ecosystem. ▪ Soil is made up of four major components besides others. These are: mineral matter, organic matter, soil water and soil air. ▪ Humification - process of degradation of dead parts of plants and animals and their conversion into humus ▪ Holard – total amount of water available in soil ▪ Chresard - water which is available to plants ▪ Echard - water unavailable to plants Three types of water available to soil: 1. Hygroscopic water - tightly held around soil particles by surface forces and cannot be removed by plants 2. Capillary water - water which fills in pore spaces 3. Gravitational water - moves downwards due to gravitational force and reaches up to deep saturated ground water ▪ Water holding capacity – percentage of water retained as capillary water in soil against gravitational force. ▪ Soil Air – important for seed germination and humification process. Poor aeration may increase the levels of CO2 thus leading to production of toxic compounds like acetic acid, formic acid, oxalic acid, hydrogen disulfide, etc., which has harmful effect on growth of plants ▪ Soil temperature - various physical and chemical processes in soil like absorption of minerals and water by roots, growth of underground parts of plant and seed germination is affected by temperature. Maximum metabolism is observed in plants between 20° to 30° C. Biotic All living species including plant, animal and microbes there is no independent existence of any organism, as all organisms whether plants or animals interact and affects each other either directly or indirectly.  GEE 302: PEOPLE AND THE EARTH’S ECOSYSTEM CUE COLUMN: Answers to review questions, Main Ecology is studied at various level of organization. ideas, Questions that connect points, Diagrams, ✓ Species/Individual Study prompts, mind maps, KEYWORDS… ✓ Population ✓ Community Research and define these levels and write it in the ✓ Ecosystem CUE COLUMN ✓ Biome ✓ Biosphere For notes and review: 1. List down the environmental factors that affect the living organisms 2. Explain the role of climatic factors in the distribution of plants 3. Explain the scope of ecology. Biotic Relationships Many biological processes such as pollination, fertilization, nutrition, growth, seed dispersal, etc., biotic interactions occur among organisms. These could be divided as: Intraspecific relationship, where interactions occur within the same biological species and Interspecific relationship, where interactions occur between two different biological species. These interacting activities act as biotic factors affecting the ecosystem in various ways. In this regard, human beings are an important biotic factor. Biotic relationships could be studied under various categories as follows: 1. Symbiosis 2. Neutralism 3. Parasitism 4. Mutualism 5. Commensalism 6. Predation 7. Amensalism 8. Proto-cooperation 9. Antagonism 10. Antibiosis 11. Competition Species interactions (Biotic relationships) Neutral - two species that don't interact at all Commensalism - beneficial to one species but neutral to another, e.g., birds that nest in trees, epiphytes (plants that grow on other plants) such as tropical orchids Mutualism - an interaction that is beneficial to both species, e.g., plants and their pollinators, plants and animals that disperse their seeds, certain fungi and plant roots Parasitism - an interaction that benefits one species and is detrimental to another. Note that the host is generally not killed. Predation - an interaction beneficial to one species and detrimental to another. In this case the prey is killed. Predators are those that kill and eat other animals. Although many organisms eat plants, they usually don’t kill them because they are a constant supply of food. Prey are killed and eaten. Amensalism - an interaction that is neutral to one species and is detrimental to another, e.g., cattle that tramples on grass—the grass is harmed while cattle are unaffected For notes and review: 1. Define other Biotic relationships that are not found above. 2. In your neighborhood, which biotic relationship is more common? Give an example Types of competition: 1. Intraspecific - competition among individuals of the same species, e.g., humans compete against other humans 2. Interspecific - competition between different species, e.g., humans compete against a wide variety of species seeking to utilize our food resources 3. The theory of competitive exclusion maintains that species who utilize the same resources cannot coexist indefinitely - the "one niche, one species" concept 4. Resource partitioning - the resources are divided, permitting species with similar requirements to use the same resources in different areas, ways, and/or times