BIOL 1108 1nd Edition Lecture 24 Outline of Last Lecture I. Learning ObjectivesII. CommunityIII. Competition IV. Symbiosis V. SuccessionVI. Species Diversity VII. Trophic Interactions and Structure Outline of Current Lecture I. Learning ObjectivesII. In The NewsIII. Ecosystem IV. Thermodynamics V. Productivity VI. Energy Transfer VII. Biogeochemical Cycles Current LectureI. Learning Objectives - Describe energy flow and nutrient cycling through an ecosystem relative to organisms living thereThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Describe productivity via trophic levels II. In The News: “Why did the mountain lion cross the freeway?”- Highway causes mountain lion populations to interbreed and lead to health problems- Male mountain lions would kill their sons as sexual competition and mates with daughters- Natal dispersal- young individuals would leave their birth homes to find mates - Genetic diversity of mountain lions in S. California study sites o One individual can make a huge difference in the gene pool within small populations - Big or small- roads affect all o Many species use underpasses to travel o Strong correlation between noise level and carnivores o Overpasses: grass on themo Also affects fish - Roads can have an impact of wildlife: traffic mortality, habitat loss, population subdivision, inaccessibility o Animals tend to stay away from cars and loud noises- Connectivity: having a corridor from one area to another - For all kinds of organismso How do roads affect Individual organisms Populations, communities, ecosystems, ect? III. Ecosystem- What is an ecosystem? o Organisms and abiotic factors that interact within a given area, including the energy flow and nutrient cycling and the structures formed by these processes IV. Thermodynamics - 1st Law of Thermodynamics- Energy cannot be created or destroyed, only transferred or transformedo Therefore, we can follow energy flow from input to its release as heat from organisms- 2nd Law of Thermodynamics- Every exchange of energy increases entropy (it is inefficient and is lost as heat)- Law of conservation of mass- Matter cannot be created or destroyedo Chemicals (nutrients) cycle and can be measured V. Productivity - Primary production- sets up what’s available for use within the ecosystem- Gross Primary Production (GPP)- what is taken in by the primary producers- Net Primary Production (NPP)- whatever is not used by the primary producers; half of the gross primary production - What are limitations to productivity in aquatic ecosystems? o Lighto Nutrients o Water - What are limitations to productivity in terrestrial ecosystems?o Watero Lighto Temperature o Soil nutrients VI. Energy Transfer - Ecological pyramids- less energy (10%) as you go up; lost as heat TOPHAT QUESTION: if choosing off of the ecological pyramid, what food should you eat to conserve energy within the ecosystems? VII. Biochemical Cycles - Water Cycleo Precipitation over ocean and lando Movement over land by windo Evaporation from ocean and evapotranspiration from land o Percolation through soil o Runoff and groundwater - Carbon Cycle o CO2 in atmosphereo Plants use photosynthesis from CO2o Consumers regulate cellular respirationo Decomposition and burning of fossil fuels and wood - Nitrogen Cycleo Decomposition and sedimentation- decomposers use nitrification and ammonification from waste of other organismso Denitrification creates runoff of nitrogen fertilizers into bodies of watero Industrial fixation leads to the reaction of nitrogen gases back into the atmosphere - Phosphorus Cycleo Fungi and other decomposers break down wasteo Phosphorus leaches into bodies of water where it is dissolved and up taken by plankton, then goes through sedimentationo Weathering of rocks, geologic uplift, and wind-blown dust lead to runoff and brings phosphorus back into the atmosphere - What affect does temperature have on the amount of mass that gets decomposed?o Decomposition increases as temperatures increase because the warmers it is the more decomposers are allowed to move and obtain