Chapter 3 Ecosystems and Energy Chesapeake Bay Salt

Chapter 3 Ecosystems and Energy

Chesapeake Bay Salt Marsh Ecosystem § § Chesapeake is an estuary (affected by tides) Tidal marshes are special because they: § § Purify water Protect the coastline Provide shelter and breeding grounds for aquatic species Are one of the most productive ecosystems in terms of energy!

Chesapeake Ecosystem § § § Water is salty on the ocean side, brackish in the middle, and fresh water at the head of the bay Base of the food web is cordgrass (shown in photo). This has an advantage since it can grow under saline conditions and periodic submergence due to tides. The bay receives high nutrient levels (N, P) from treated human sewage and farm runoff, which promotes algal growth (cordgrass too), which serve as food for other organisms.

What is the Chesapeake like? Major kinds of life in the salt marsh ecosystem: 1. Insects Ø Millions of mosquitoes and horseflies 2. Birds Ø Sparrows, hulls, clapper rails 3. Shrimp, lobster, crabs, barnacles, worms, clams and snails are all present and seek refuge in the cordgrass. Ø No amphibians live there (salt) but the terrapin turtle does. 4. Numerous species of fish call the Chesapeake home…including: Ø Sea trout, croaker, bluefish, striped bass Ø Young species enter from the ocean. 5. Meadow voles live along the shores, and are excellent

What does the Chesapeake Tell Us? § § This ecosystem is interdependent upon human inputs (pollutants such as nitrates, phosphates and others like oil, gas, etc. ) and also it’s natural setting. It remains one of the most productive ecosystems on the planet…but it is in peril! Too much pollution…overfishing…too many nutrients (eutrophication)…oil spills…. growing population…. It is important to protect our most productive ecosystems!

Chesapeake Ecosystem n Chesapeake also serves as an excellent case study in how energy flows through an ecosystem!

Overview of Chapter 3 § § What is Ecology? The Energy of Life § § § Laws of Thermodynamics Photosynthesis and Cellular Respiration Flow of Energy Through Ecosystems § § § Producers, Consumers & Decomposers Ecological Pyramid Ecosystem Productivity

Ecology § § § Biotic - living environment § § “eco” house & “logy” study of The study of interactions among and between organisms in their abiotic environment Includes all organisms Abiotic - non living or physical environment § Includes living space, sunlight, soil, precipitation, etc.

Ecology § Ecologists are interested in the levels of life above that of organism

Ecology Definitions § Species § § Population § § Al the populations of different species that live and interact in the same area at the same time Ecosystem § § A group of organisms of the same species that occupy that live in the same area at the same time Community § § A group of similar organisms whose members freely interbreed A community and its physical (abiotic) environment Landscape § Several interacting ecosystems

Ecology § Biosphere contains earth’s communities, ecosystems and landscapes, and includes: § § § Atmosphere gaseous envelope surrounding earth Hydrosphere earth’s supply of water Lithosphere - soil and rock of the earth’s crust

The First & Second Law of Thermodynamics By: Michelle Zicca

Basic Laws of Thermodynamics n First Law of Thermodynamics – energy can neither be created nor destroyed n Second Law of Thermodynamics – naturally occurring processes are directional

First Law of Thermodynamics One form of work may be converted into another, n or, work may be converted to heat, n or, heat may be converted to work, n but, final energy = initial energy n

2 nd Law of Thermodynamics n We intuitively know that heat flows from higher to lower temperatures and not the other direction. – i. e. , heat flows “downhill” just like water – You cannot raise the temperature in this room by adding ice cubes. n Thus processes that employ heat are inherently irreversible.

Heat/Work Conversions Heat transfer is inherently irreversible. This places limits on the amount of work that can be produced from heat. n Heat can be converted to work using heat engines n – Jet engines (planes), steam engines (trains), internal combustion engines (automobiles)

Open & Closed Systems Open system exchanges energy with its surroundings n A closed system is self-contained and isolated; does not exchange energy with its surroundings. n

Where did the energy go? By the First Law of Thermodynamics, the energy we put into the water (either work or heat) cannot be destroyed. n The heat or work added increased the internal energy of the water. n

Processes that take Place n Reversible Processes n A reversible process is a quasi-equilibrium, or quasi-static, process with a more restrictive requirement. n Internally reversible process n n n The internally reversible process is a quasi-equilibrium process, which, once having taken place, can be reversed and in so doing leave no change in the system. This says nothing about what happens to the surroundings about the system. Totally or externally reversible process The externally reversible process is a quasi-equilibrium process, which, once having taken place, can be reversed and in so doing leave no change in the system or surroundings.

Overview of Thermodynamics Two constraints on life processes – Evolutionary history – Physics and chemistry • Living things must play by these rules • Order is sustained in living things at the expense of energy and disorder to the surroundings n

Pictures and Examples

Three Types of Process Isothermal process System Adiabatic process P Adiabat Isotherm Heat bath or reservoir Adiabatic free expansion V P 1 ● End points 2 ● V 27

Photosynthesis, Cellular Respiration, and Chemosynthesis By Wesley Washington

Photosynthesis • It is a biological process where plants such as algae, and some bacteria take in light energy and change it into carbohydrates (sugar). • Glucose is the molecule that is formed by photosynthesis. Glucose is the fuel source of plants.

Photosynthesis The carbon dioxide(6 CO 2) and water(12 H 2 O) is synthesized with sunlight to form glucose(C 6 H 12 O 6). Left over products include water which is stored and Oxygen which is released.

Aerobic Cellular Respiration • Is essentially is the process of the cells using energy to biological work. • All organisms need to respire. Plants use glucose energy while most animals breathe. • This process usually needs oxygen, however anaerobic bacteria hat lives in waterlogged soil, animal intestines (like yours!) and hydrothermal vents still respire without oxygen.

Chemosynthesis • Happens at hydrothermal vents on the bottom of the sea floor. • Bacteria living there is able to with stand temperatures of 392 F • The vents spew out mineral rich water and toxic hydrogen sulfide.

Chemosynthesis • The bacteria takes the raw inorganic chemicals and process them into food of the bacteria. • Organisms such as the giant red tube worms have a symbiotic relationship with the bacteria allowing them to live inside their bodies in exchange for the energy they produce.

Producers, Consumers, and Decomposers by: Joey Harkins • All organisms are classified as either a producer, consumer, or decomposer • The basis of the classification is on how each organism receives its nourishment

Producers • Producers (autotrophs)organisms that manufacture complex organic molecules from simple inorganic substances, such as CO 2 and water, and using the energy from the sun. • For example photosynthetic organisms • Producers incorporate the chemicals they manufacture into their own bodies, becoming food sources for other animals.

Consumers • Consumers (heterophs)- use the bodies of other organisms as a source of food energy and bodybuilding materials. • Four types of consumers: primary consumers- herbivores, only eat producers secondary consumers- eat primary consumers tertiary consumers- eat secondary consumers detritus feeders- consume organic matter, like animal carcasses, leaf litter, and feces

Decomposers • Decomposers (saprotrophs)- heterotrophs that break down dead organic material and use the decomposition products to supply themselves with energy. • Decomposers release inorganic molecules, such as CO 2 and mineral salts, that producers can reuse. • Bacteria and fungi are some examples of decomposers

• Producers, consumers, and decomposers all play an important role in the ecosystem. • Producers provide food and oxygen for the community • Consumers maintain a balance between producers and decomposers. • Decomposers keep dead organisms and waste products to a minimum, while also releasing the potassium, nitrogen, and phosphorus from dead organisms.

The Path of Energy: Who Eats Whom in Ecosystems? Hunter Longenberger

In an Ecosystem • Energy passes from one organism to the next through a food chain • Many interconnected food chain forms a food web • Within each food chain there are trophic levels Food web (everything is connected) Food chain (just one path of energy)

Food Web

Trophic levels • • Is where the organism stands in the food web This is based on the number energy transfer steps to that level • Tropic levels 1. Producers (organisms that photosynthesize) 2. Primary consumers (herbivores) 3. Secondary consumers (carnivores) • At every step in the food chain there are decomposers

Trophic levels Secondary consumers Primary consumers Producers

Energy flow • It is linear or one way • Once an organism has used energy it is lost as heat and is unavailable for any other organism in the ecosystem

Human Impact on the Antarctic food Web Ryan Privitera

The Antarctic food web § Everywhere in the world there are predators and prey meaning the lower you are on the web means that you are a primary source to other species. § Going from the diversity of the rain forest where the web is large and complicated as compared to one of the simplest webs, the Antarctic.

They call us humans. § The number one environmental problem we face as a society simply is our population growth. § The more humans reproduce the worse off the planet is going to be and the number increases each day by 353015 babies. § § The united states alone produces 10650 a day. That’s an outrageous number and believe it or not this is the main reason for impacting any food web and we seem to disturb the simplest one.

Antarctica § This is a place of vacancy which means no civilized human life forms live there year round for the reason that tempters can drop to -89. 2 ° Celsius. § This baron land is home to penguins, polar bears, weddell seals, blackbrowed albatross, leopard seals, elephant seals, and crabeater seals.

Human impacts § Antarctica is one of the most important research centers for environmental warming and melting of ice. § Antarctica's clean air, water and ice of are of importance to science for understanding how the Earth's environment is changing both naturally and as a result of human activity due to the increasing hole over the Antarctic. § Pollution drifts into the air and contaminates the normal levels of our atmosphere.

This is the marine ecosystem.

The simplicity of the food web.

Rusting metal in antarctica.

Rusted metal waste barrells.

Warming chart

Realizing our mistakes § The best way to fix any mistake is not to do it again so what we have to do as a society is realize that we do anywhere in the world will have serious consequences if we keep living like Americans. § The ignorance of others will ruin this ecosystem if we simply keep overusing fuels and not using renewable energies.

Ecological Pyramids Maddie Lewis

• Most energy going from one trophic level to the next dissipates into the environment due to the second law of thermodynamics. • Ecological pyramids graphically represent relative energy levels at each level • There are three types of ecological pyramids

Pyramid of Numbers • Shows number of organisms at each trophic level, greater numbers are shown by a larger area • In most, organisms at the base of the food chain are more abundant • Inverted pyramids of numbers are when higher trophic levels have more organisms, seen in decomposers, parasites, etc.

Pyramid of Biomass • Biomass- quantitive estimate of total mass or amount of living material, indicates fixed energy • Represented as live weight, total volume or dry weight • Succeeding trophic levels usually show reduction of biomass

Pyramid of Energy • Illustrates energy of biomass at each level • Usually measured in kilocalories per year • Always have large energy bases and get progressively smaller • Less energy reaches each level because organisms use it, and some is lost • Food webs are short due to dramatic reduction in energy

ECOSYSTEM PRODUCTIVITY MERICA

Gross Primary Productivity • GPP of an ecosystem is the rate at which energy is captured during photosynthesis! MERICA

Net Primary Productivity • NPP is energy in plant tissues after cellular respiration has occurred! • NPP is the amount of biomass found in excess of that broken down by plant’s cellular respiration!

GPP=NPP + Respiration

More! • Both GPP and NPP are expressed as energy per unit area per unit time, or as dry weight. • Consumers use most energy from NPP for cellular respiration and to contract muscles.

RECENTLY • In 1986 Peter Vitousek calculated how much of global NPP is appropiated for the human economy and therefore not transferred to other organisms. He determined humans use 32% of the annual NPP of landbased organisms. • In 2001 Stuart Rojstaczer reexamined Vitousek’s experiment and agreed with his result of 32% usage. • In 2007 K. Heinz Erb put 97% of the Earth’s forestry information into a computer model. The model states humans are appropriated about 25%.