Midterm Study Guide

What is the ocean fertilization hypothesis and how did it come about?

"The iron hypothesis" - John Martin Past climate shows correlations to support: - High dust and iron - Lower CO2 and temperature Basically: 1) That adding Fe to oceans increases primary production 2) That the CO2 capture by these algae and turned into C incorporated into their bodies sinks to the deep ocean Getting carbon into the ocean is one matter—getting it down to the deep ocean is another! About 50 Gt of C is drawn down into the biological pump per year but only a small fraction of this carbon makes its way down into the deep ocean (2007 IPCC). (From Beedlow et al. 2004 - what is the oceanic sink??)

Describe pros and cons for monocropping.

1. Easy, Simple and Focused Monoculture is simple. A farmer doesn't have to bother about multiple varieties of a single crop or multiple crops. One would grow only one variety of rice or potato, wheat or clover, corn or cotton. The land doesn't have to be irrigated different for different crops. The entire focus is on one growth cycle, one type of crop, its needs and the maximum produce possible. Harvesting is easy too. One doesn't have to deal with pests bearing in mind the possible impact on other crops. 2. More Affordable, More Rewarding Monoculture is more affordable. The investment is reasonable given the needs of only one crop must be met. Harvesting is simpler and hence less labor intensive. All tools, farming methods and additional resources are used efficiently and more systematically with the singular objective of maximizing the output. 3. Better Execution, More Surefire Returns A farmer gets to learn more about one crop and becomes an expert. It is not easy to learn everything about half a dozen crops. Farmers develop a degree of authority and can easily tackle challenges pertaining to growing the chosen crop. From preventing diseases to mastering the techniques to have the highest yields, everything becomes more decisive. List of Cons of Monoculture 1. Underutilized Soil Nutrients If a particular piece of farmland has more nutrients than those needed for the chosen crop then that would be wasted. Not utilizing or underutilizing soil nutrients is a form of wastage seen from the perspective of agriculture or farming. 2. Limited Food Choices Monoculture focuses on a single crop and one that can be readily grown on a farm with the least effort. This encourages growing crops that have become staples in different countries. There will be fewer food options if all farmers chose monoculture. Also, there can be a surplus production of a few crops leading to unsold and wasted produce with no or limited production of other crops. 3. Diminishing Soil Fertility The same crop being grown every year will reduce the nitrogen content in the soil. This will diminish its fertility.

Describe how a nuclear reactor works, compare/contrast with a fossil fuel power plant

A fossil-fueled power plant relies on the ancient technology of fire to produce heat; such plants burn hydrocarbon fuels such as methane or pulverized coal. The process of combustion releases energy from the chemical bonds in the fuel. By contrast, nuclear reactors exploit the heat of radioactivity. The heavy, unstable atoms of uranium-235 and plutonium-239, both common nuclear fuels, decay into lighter elements while generating abundant heat. Hazards exist with both fossil fuel and nuclear power plants, although many of the dangers are different. The reactor design of most operating nuclear plants requires the constant flow of water to keep the reactor from overheating and possibly releasing radioactivity into the environment; the Fukushima disaster in 2011 happened when water pumps failed. Coal-fired power plants generate large amounts of ash, solid waste that contains mercury, arsenic and other hazardous materials. Some plant operators contain the ash in gigantic ponds, which may rupture, contaminating the surrounding area. Such an accident happened in Tennessee in 2008, releasing 1.3 million cubic meters - 1.7 million cubic yards - of ash slurry. The combustion reactions that power a fossil fuel plant consume fuel and oxygen and produce water vapor, carbon dioxide and energy. The combustion of coal, natural gas and oil always yields CO2, a gas believed to be strongly connected to global warming. Because coal and oil have noncombustible impurities, these sources also produce nitrous oxides, sulfur dioxide and other pollutants. A nuclear power plant does not use chemical reactions to produce energy; during normal operations, it has no gaseous emissions.

Compare the characteristics of a keystone species with a foundational species, and an ecosystem engineer

A keystone species has a disproportionately large effect on its environment relative to its abundance. These species are described as playing a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem. They help to determine the types and numbers of various other species in the community. Without a keystone species, the ecosystem would be dramatically different or cease to exist altogether. A foundation species is a species that has a strong role in structuring a community. The activities of foundation species physically modify the environment and produce and maintain habitats that benefit other organisms using that benefit. The presence of foundation species has the ability to either reduce or increase species diversity depending on its particular role in a specific ecosystem. This term is often applied to a range of terrestrial and aquatic ecosystems. An ecosystem engineer is any organism that creates, significantly modifies, maintains or destroys a habitat. These organisms can have a large impact on the species richness and landscape-level heterogeneity of an area.[1] As a result, ecosystem engineers are important for maintaining the health and stability of the environment they are living in. Since all organisms impact the environment they live in in one way or another, it has been proposed that the term "ecosystem engineers" be used only for keystone species whose behavior very strongly affects other organisms

Recognize positive and negative feedback cycles.

A positive feedback loop occurs in nature when the product of a reaction leads to an increase in that reaction. If we look at a system in homeostasis, a positive feedback loop moves a system further away from the target of equilibrium. It does this by amplifying the effects of a product or event and occurs when something needs to happen quickly. A negative feedback loop occurs in biology when the product of a reaction leads to a decrease in that reaction. In this way, a negative feedback loop brings a system closer to a target of stability or homeostasis. Negative feedback loops are responsible for the stabilization of a system, and ensure the maintenance of a steady, stable state. The response of the regulating mechanism is opposite to the output of the event.

Describe the role of keystone species in an ecosystem; describe direct and indirect effects

A species that plays a role in its community that is far more important than its relative abundance might suggest. A series of classic ecological experiments by Paine in the 1960s helped to elucidate this indirect effect model. In keystone predation, the removal of a prey species by the predator indirectly increases the abundance of a competitor of the prey species. Menge (1995) found that keystone predation was the most common of the indirect effects observed in intertidal studies with 35% of the interactions falling in to this model.

Illustrate how humans are changing these fluxes. Trace the pathway of "anthropogenic" carbon. Explain how anthropogenic activities are changing the carbon cycle.

AND THIS

how do, if at all, mass number and atomic number differ between isotopes

Atoms of each element contain a characteristic number of protons. In fact, the number of protons determines what atom we are looking at (e.g., all atoms with six protons are carbon atoms); the number of protons in an atom is called the atomic number. In contrast, the number of neutrons for a given element can vary. Forms of the same atom that differ only in their number of neutrons are called isotopes. Together, the number of protons and the number of neutrons determine an element's mass number: mass number = protons + neutrons. If you want to calculate how many neutrons an atom has, you can simply subtract the number of protons, or atomic number, from the mass number.

Applied vs basic research

Basic (aka fundamental or pure) research is driven by a scientist's curiosity or interest in a scientific question. The main motivation is to expand man's knowledge, not to create or invent something. There is no obvious commercial value to the discoveries that result from basic research. Applied research is designed to solve practical problems of the modern world, rather than to acquire knowledge for knowledge's sake. One might say that the goal of the applied scientist is to improve the human condition.

Discuss limits on CO2 sequestration into the biosphere via photosynthesis

Biological processes which transfer organic matter and associated elements to depth - Pathway for rapid C sequestration - Can quickly remove C from surface ocean and atmosphere

Compare fundamental and realized niches

Both fundamental and realized niches refer to the environmental position that species occupy in an ecosystem. Fundamental niches represent all the environmental conditions where a species is able to live, and the realized niche is where the species actually lives. Other names for these niches are precompetitive and postcompetitive, respectively. In a fundamental niche, an organism can take advantage of all the biotic and abiotic factors in an ecosystem without competition from other species or pressure from predators. This niche narrows when other organisms arrive and there is competition for food and breeding partners or when predators start hunting in the area. The organism will survive if it adapts to the new conditions of its realized niche. Fundamental niches are the same size or larger than realized niches. Also, the same species living in different locations may have different realized niches depending on the competitors and predators that are present. Fundamental and realized niches can be wide or narrow. Specialist species is the term for organisms that live in narrow niches because they thrive only in certain environmental conditions or eat a certain food. Conversely, generalist species occupy wider niches and make use of a variety of resources and can live in many different environmental conditions. The niche that an organism occupies may change dramatically over the course of its life. An example of this is when a tadpole which is an herbivore, undergoes metamorphosis into a carnivorous frog.

Draw graphs depicting bottom-up control vs. top-down control

Bottom up: predators: \ forage fish: \ zooplankton: \ phytoplankton: \ Top Down: predators: \ forage fish: / zooplankton: \ phytoplankton: /

Describe species interactions, give examples

Competitive exclusion principle: two species competing for the same limiting resources cannot coexist. This can lead to resource partitioning. Resource partitioning: two species co-evolve to divide a limiting resource, through differences in species behavior or form. Predators are found in four forms: true predators, herbivores, parasites, and parasitoids. Mutualism A type of interspecific interaction where both species benefit Commensalism A type of relationship in which one species benefits but the other is neither harmed nor helped.

How do corridors help with conservation? What species are more likely to require corridors between habitats?

Corridors are habitats that are typically long relative to their width, and they connect fragmented patches of habitat. They can vary greatly in size, shape, and composition. The main goal of corridors is to facilitate movement of individuals, through both dispersal and migration, so that gene flow and diversity are maintained between local populations. By linking populations throughout the landscape, there is a lower chance for extinction and greater support for species richness. Corridors work by increasing connectivity between patches that are isolated by human habitat fragmentation, caused primarily by urbanization, agriculture, and forestry. Plants and animals can use corridors for both dispersal and migration, two key movement patterns for species persistence. The human-dominated habitats surrounding more natural areas present barriers that plants and animals are unable or highly reluctant to move through. These inhospitable places may have higher abundances of predators, lower resource availability, or reduced shelter. When a corridor is present, however, it provides an unbroken path of suitable habitat that can provide safe passage for animals or plants without being hindered as they travel through agricultural or urban landscapes. This connectivity is key to population persistence, as it promotes gene flow between populations and supports higher species diversity.

differences between inductive and deductive reasoning.

Deductive reasoning, or deduction, starts out with a general statement, or hypothesis, and examines the possibilities to reach a specific, logical conclusion Inductive reasoning makes broad generalizations from specific observations. Basically, there is data, then conclusions are drawn from the data. This is called inductive logic

Contrast the ways in which density-dependent and density-independent factors affect population size

Density-dependent limiting factors tend to be biotic—living organism-related—as opposed to physical features of the environment. Some common examples of density-dependent limiting factors include: Competition within the population. When a population reaches a high density, there are more individuals trying to use the same quantity of resources. This can lead to competition for food, water, shelter, mates, light, and other resources needed for survival and reproduction Predation. Higher-density populations may attract predators who wouldn't bother with a sparser population. When these predators eat individuals from the population, they decrease its numbers but may increase their own. This can produce interesting, cyclical patterns, as we'll see below. Disease and parasites. Disease is more likely to break out and result in deaths when more individuals are living together in the same place. Parasites Waste accumulation. human activities unusual weather natural disasters

What is a ½ life?

Each half-life, the number of parent isotopes reduces by half

Define ecology

Ecology is the study of how organisms interact with one another and with their physical environment. The distribution and abundance of organisms on Earth is shaped by both biotic, living-organism-related, and abiotic, nonliving or physical, factors. Ecology is studied at many levels, including organism, population, community, ecosystem, and biosphere.

What is the 1st law of thermodynamics?

Energy cannot be created or destroyed

List the environmental impacts of coal and discuss each.

Environmental impacts of coal • Mining • Air pollution (but also into hydrosphere and biosphere) • CO2 • SO2 & particulates - smog • SO2 and NOx - Acid drainage and rain • Wastes & thermal pollution • Coal fires (+ subsidence)

List the environmental impacts of using nuclear fission with U-235 and discuss each

Environmental impacts: • Radiation • Radioactive wastes • Potential for accidents • Scope for nuclear weapons proliferation • May be costly • (Not entirely CO2 free - takes steel, etc. to build reactors, energy involved in enrichment)

What is the difference between weathering and erosion? List examples for each.

Erosion • Physical removal of rock fragments from landscape or ecosystem • Wind, water, ice transport soil and minerals downslope under gravity • loss of soil fertility reduces plant growth • leads to additional fertilizer applications Deposition: accumulation of eroded material (i.e. sediment, rock, soil) • Often in waterways weathering: Weathering Mechanical/physical • Water, wind, variations in temperature (e.g., freeze-thaw cycles) • Biological agents (e.g. plant roots, burrowing animals) • Human: compaction causing a decrease in infiltration capacity of the soil, changing runoff Chemical • Chemical rxns, dissolving of chemical elements from rocks, or both • Natural - acids (e.g., produced by lichens) or rocks contain compounds that dissolve easily (e.g., calcium carbonate) • Human -acid rain, salinization, fertility depletion/decrease in cation retention capacity

What is the difference between Gross Primary Production and Net Primary Production?

Gross Primary Productivity (GPP) • Total amount of energy that plants capture and assimilate in a given period of time Net Primary Productivity (NPP) • NPP = GPP - cellular respiration • Plant growth per unit area per time • rate at which organic material is actually incorporated into the plant tissue for growth • Only NPP is available as food to organisms

How is succession relevant to fire ecology?

Fire and ecological succession. ... Ecologists usually characterize succession through the changes in vegetation that successively arise. After a fire, the first species to re-colonize will be those with seeds are already present in the soil, or those with seeds are able to travel into the burned area quickly.

Compare the trade offs (pros and cons) of fossil fuels and nuclear power

Fossil Fuel Pros: Systems are set up process and utilize oil and gas Widely available around the globe low cost per unit energy Refineries, transportation, and plastics all rely heavily on oil and gas High energy output Employs millions of people globally The primary source of all plastics Fossil Fuel Cons: Finite resource Large greenhouse gas emitter including CO2 Progressively harder to find oil and gas deposits Global movement toward limiting oil and gas and using renewable energy sources Environmentally damaging, with potential catastrophic damage from large oil spills Produces smog which harms human health Pros of Nuclear Energy 1. Low Pollution 2. Low Operating Costs 3. Reliability: 4. More Proficient Than Fossil Fuels: 5. Renewable?: Nuclear energy is not renewable resource. Uranium, the nuclear fuel that is used to Cons of Nuclear Energy 1. Environmental Impact 2. Radioactive Waste Disposal: 3. Nuclear Accidents 4. High Cost 5. Uranium is Finite: 6. Hot Target for Militants

Describe where you would find coal and why you would find it there.

Fossil fuels are formed from the remains of ancient organisms. Because coal takes millions of years to develop and there is a limited amount of it, it is a nonrenewable resource. The conditions that would eventually create coal began to develop about 300 million years ago, during the Carboniferous period. During this time, the Earth was covered in wide, shallow seas and dense forests. The seas occasionally flooded the forested areas, trapping plants and algae at the bottom of a swampy wetland. Over time, the plants (mostly mosses) and algae were buried and compressed under the weight of overlying mud and vegetation. As the plant debris sifted deeper under Earth's surface, it encountered increased temperatures and higher pressure. Mud and acidic water prevented the plant matter from coming into contact with oxygen. Due to this, the plant matter decomposed at a very slow rate and retained most of its carbon (source of energy). These areas of buried plant matter are called peat bogs. Peat bogs store massive amounts of carbon many meters underground. Peat itself can be burned for fuel, and is a major source of heat energy in countries such as Scotland, Ireland, and Russia. Under the right conditions, peat transforms into coal through a process called carbonization. Carbonization takes place under incredible heat and pressure. About 3 meters (10 feet) of layered vegetation eventually compresses into a third of a meter (1 foot) of coal! Coal exists in underground formations called "coal seams" or "coal beds." A coal seam can be as thick as 30 meters (90 feet) and stretch 1,500 kilometers (920 miles). Coal seams exist on every continent. The largest coal reserves are in the United States, Russia, China, Australia, and India. In the United States, coal is mined in 25 states and three major regions. In the Western Coal Region, Wyoming is the top producer—about 40% of the coal mined in the country is extracted in the state. More than one-third of the nation's coal comes from the Appalachian Coal Region, which includes West Virginia, Virginia, Tennessee, and Kentucky. Coal extracted from Texas in the Interior Coal Region supplies mostly local markets.

Describe pros/cons for pesticides

Gains associated with pesticide use include: 1. Economics of pesticide production:$50 billion dollar business - about 40% is exported to other countries. 2. It has been estimated that millions of lives have been saved from death through malaria, yellow fever, sleeping sickness, Black plague and typhoid 3. With respect to agriculture- 35% lost before cropping and 20% post with pesticides ; without pesticide another 8% of additional damage would occur. The psychological damage ( non perfect fruit and vegetables) would be even greater- 20-90% 4. Forestry - millions of acres have been sprayed; Spruce budworm and gypsy moth. some contend however that these insects cycle normally and would decrease without the use of pesticides. Cons associated with pesticide use: 1. Genetic resistance - every year the number of resistant species evolving increases Today, nearly 275 weeds and more than 500 insects are resistant to at least one pesticide. That's more than five times the amount in 1950. And farmers lose more crops to pests today than they did in the 1940s. 2. Most chemical pesticides are nonspecific - effect a large number of species, pest and non-pest 3. Pesticides treadmill: from 1940 --> 1984 crop loss has increased from 7 --> 13% while pesticide use increased 12X. Why? with spraying we have killed the predators of the pests, and once the pest species is released from natural controls ( both no predation and no competition) their populations escalate! 4. With aerial application, only 10% reaches the crop and only 0.1%-5% reaches the targeted pest. 5. Pesticide use has threatened and continues to impact wildlife negatively. 6. Each year WHO estimates 1-5 million people have acute poisoning and die. In the US, 20,000 are estimated to suffer from some form of pesticide poisoning.

Compare total annual energy consumption to per capita consumption

Generally, USA, Australia, Canada, and France have high energy per capita consumption total consumption is high in USA and china

What is the 2nd law of thermodynamics?

Heat will always flow from an area of higher temperature to an area of lower temperature.

Where does carbon have to be sequestered in the terrestrial biome to be stored more long term?

INCREASING FOREST DENSITY DECREASES CARBON IN THE ATMOSPHERE passive pools

Define community ecology

In ecology, a community is a group or association of populations of two or more different species occupying the same geographical area and in a particular time, also known as a biocoenosis. The term community has a variety of uses. In its simplest form it refers to groups of organisms in a specific place or time, for example, "the fish community of Lake Ontario before industrialization". Community ecology or synecology is the study of the interactions between species in communities on many spatial and temporal scales, including the distribution, structure, abundance, demography, and interactions between coexisting populations.[1] The primary focus of community ecology is on the interactions between populations as determined by specific genotypic and phenotypic characteristics. Community ecology has its origin in European plant sociology. Modern community ecology examines patterns such as variation in species richness, equitability, productivity and food web structure (see community structure); it also examines processes such as predator-prey population dynamics, succession, and community assembly.

Define strong inference

In philosophy of science, strong inference is a model of scientific inquiry that emphasizes the need for alternative hypotheses, rather than a single hypothesis to avoid confirmation bias. The term "strong inference" was coined by John R. Platt,[1] a biophysicist at the University of Chicago. Platt notes that some fields, such as molecular biology and high-energy physics, seem to adhere strongly to strong inference, with very beneficial results for the rate of progress in those fields. The method, very similar to the scientific method, is described as: Devising alternative hypotheses; Devising a crucial experiment (or several of them), with alternative possible outcomes, each of which will, as nearly as possible, exclude one or more of the hypotheses; Carrying out the experiment(s) so as to get a clean result; Recycling the procedure, making subhypotheses or sequential hypotheses to refine the possibilities that remain, and so on.

List the environmental impacts of using oil and discuss each.

Just 1 litre of oil can contaminate 1 million litres of water. Oil pollution can have a devastating effect on the water environment, it spreads over the surface in a thin layer that stops oxygen getting to the plants and animals that live in the water. Oil pollution: harms animals and insects prevents photosynthesis in plants disrupts the food chain takes a long time to recover

Describe logistic growth

Logistic growth is when growth rate decreases as the population reaches carrying capacity. Carrying capacity can be defined as maximum number of individuals in a population that can be supported by the environment. dN/dT = rN(K-N/K)

compare and contrast logistic growth with exponential growth

Logistic growth occurs when there are limited resources due to competition; it slows, stops, and has a period of exponential growth. Exponential growth occurs when there is unlimited resources due to little competition; individuals produce at a constant rate.

Understand the soil degradation processes that lead to desertification.

Main causes of soil degradation and problems: (1) Erosion (vs. weathering) (2) Nutrient loss (3) Salinization (understand how irrigation leads to this) (4) Desertification (which regions are most sensitive?) (5) Land loss (6) Pollution

What are factors that control the rate of nitrification?

N2 gas is very stable due to the strength of the triple bond between the nitrogen atoms; it requires a large amount of energy to break this bond • Only a select group of prokaryotes are able to carry out this energetically demanding process • Some nitrogen-fixing organisms are free-living while others are symbiotic nitrogen-fixers, which require a close association with a host to carry out the process • All have enzyme complex called nitrogenase that catalyzes the reduction of N2 to NH3 (ammonia)

Link the carbon cycle to the nitrogen cycle - how do changes in the nitrogen cycle (and what changes?) impact photosynthesis?

Nitrogen is necessary because it allows for plants to grow, and plants assist in the capture of carbon. • 4 ways to increase nitrogen availability: • N reallocated from within the plant, • increased mineralization from litter and soil, • fertilizer, • air pollution. • While air pollution seems bad, it increases N deposition and allows for more C sequestration.

Describe exponential growth including all the variables that we consider when modeling exponential growth and explain what each indicates

Nt = pop's future size r = intrinsic growth rate t = time Delta N = ? dN/dt = rN Per capita growth rate (r) doesn't change, even if pop. gets very large

Distinguish between nuclear fission and fusion

Nuclear fission = one atomic nucleus is split into smaller fragments, releasing energy (HEAVY nucleus)Nuclear fission • U-235 is bombarded with neutrons • The nucleus absorbs neutrons • It becomes unstable and splits into 2 atoms • Emitted, free neutrons bombard another U235 atom - a chain reaction occurs • Nuclear fusion = two atomic nuclei join into a single, heavier nucleus, releasing energy (LIGHT nuclei)

Define nuclei

Nucleus Definition In chemistry, a nucleus is the positively charged center of the atom consisting of protons and neutrons. It's also known as the "atomic nucleus". The word "nucleus" comes from the Latin word nucleus, which is a form of the word nux, which means nut or kernel. The term was coined in 1844 by Michael Faraday to describe the center of an atom. The sciences involved in the study of the nucleus, its composition, and characteristics are called nuclear physics and nuclear chemistry. Protons and neutrons are held together by the strong nuclear force. Electrons, although attracted to the nucleus, move so fast they fall around it or orbit it at a distance. The positive electrical charge of the nucleus comes from the protons, while the neutrons have no net electrical charge. Nearly all the mass of an atom is contained within the nucleus, since protons and neutrons have much more mass than electrons. The number of protons in an atomic nucleus defines its identity as an atom of a specific element. The number of neutrons determines which isotope of an element the atom is.

Distinguish between the processes of coal and oil formation.

Peat (not coal) Lignite (brown coal) Bituminous Coal (soft coal) Anthracite (hard coal) Heat Pressure Pressure Pressure Heat Heat Partially decayed matter in swamps and bogs; low heat content Low heat content; low S content; limited in most areas Extensively used as fuel b/c of high heat content and availability; normally high S content Highly desirable b/c of high heat content & low S content; reserves limited in most areas

What is peer-review in science?

Peer review does the same thing for science that the "inspected by #7" sticker does for your t-shirt: provides assurance that someone who knows what they're doing has double-checked it. In science, peer review typically works something like this: 1) A group of scientists completes a study and writes it up in the form of an article. They submit it to a journal for publication. 2) The journal's editors send the article to several other scientists who work in the same field (i.e., the "peers" of peer review). 3) Those reviewers provide feedback on the article and tell the editor whether or not they think the study is of high enough quality to be published. 4) The authors may then revise their article and resubmit it for consideration. 5) Only articles that meet good scientific standards (e.g., acknowledge and build upon other work in the field, rely on logical reasoning and well-designed studies, back up claims with evidence, etc.) are accepted for publication. Peer review and publication are time-consuming, frequently involving more than a year between submission and publication. The process is also highly competitive. For example, the highly-regarded journal Science accepts less than 8% of the articles it receives, and The New England Journal of Medicine publishes just 6% of its submissions. Peer-reviewed articles provide a trusted form of scientific communication. Even if you are unfamiliar with the topic or the scientists who authored a particular study, you can trust peer-reviewed work to meet certain standards of scientific quality. Since scientific knowledge is cumulative and builds on itself, this trust is particularly important. No scientist would want to base their own work on someone else's unreliable study! Peer-reviewed work isn't necessarily correct or conclusive, but it does meet the standards of science. And that means that once a piece of scientific research passes through peer review and is published, science must deal with it somehow — perhaps by incorporating it into the established body of scientific knowledge, building on it further, figuring out why it is wrong, or trying to replicate its results.

Define Population ecology

Population ecology is a sub-field of ecology that deals with the dynamics of species populations and how these populations interact with the environment.[1] It is the study of how the population sizes of species change over time and space. The term population ecology is often used interchangeably with population biology or population dynamics. The development of population ecology owes much to demography and actuarial life tables. Population ecology is important in conservation biology, especially in the development of population viability analysis (PVA) which makes it possible to predict the long-term probability of a species persisting in a given habitat patch. Although population ecology is a subfield of biology, it provides interesting problems for mathematicians and statisticians who work in population dynamics.

Understand which kinds of disturbances would initiate primary or secondary succession.

Primary • Volcano • Landslide • Flooding • Lake Drainage • Tsunami Secondary • Fire • Hurricane • Logging

Describe the processes of ecological succession and how do they differ? How does biodiversity and plant community composition change?

Primary succession • After severe disturbance the remove or bury products of the ecosystem Secondary succession • After disturbance on a vegetated site. • Most above ground biomass may be disturbed but soil organic matter and plant propagules remain Process of Succession Dispersal - getting to the site • Small seeds arrive first, wind blown • Colonization and recruitment • Establishment, facilitation and inhibition • Facilitation: Colonizers - "Pioneer Species" - modify environment so it becomes less suitable for themselves and more suitable for species of later successional stages • Inhibition: Early occupants of an area modify env. in a way that makes it less suitable for both early and late successional species

Describe pros/cons for geneticially modified foods

Pros of GM foods Scientists genetically engineer seeds for many reasons. For example, they sometimes make changes designed to increase a plant's: resistance to insects tolerance to herbicides tolerance for heat, cold, or drought crop yield They also engineer seeds to give GM foods stronger colors, increase their shelf life, or eliminate seeds. That's why we can buy seedless watermelons and grapes. Some GM foods also have been engineered to have higher levels of specific nutrients, such as protein, calcium, or folate. Proponents of GM food contend that genetic engineering can help us find sustainable ways to feed people. Specifically, in countries that lack access to nutrient-rich foods. The heartiness of some GM crops makes it so they can grow in marginal environments. The longer shelf life of some GM foods allows them to be shipped to remote areas. Potential cons of GM foods On the other hand, some people wonder if GM foods are safe and healthy to eat. Genetic engineering is a relatively new development. As a result, research on the long-term health effects of GM foods is limited. GM foods have to meet the same safety requirements as foods grown from non-GM seeds. But critics suggest there's more to be concerned about. Some people worry that GM foods may be linked to allergies, antibiotic resistance, or cancer. Others suggest these concerns are unfounded. Here's what the research says. Allergies Food allergies are a growing problem in the United States. According to the Centers for Disease Control and Prevention (CDC), food allergies in children under 18 years of age have increased; from 3.4 percent between 1997 and 1999 to 5.1 percent between 2009 and 2011. Some people believe that spike is linked to GM foods. But there's no evidence that GM foods in general are more likely to trigger allergic reactions than non-GM foods, according to a study from Harvard University. Others raise concerns about the transfer of specific proteins from one plant to another in genetic engineering. Proteins found in a relatively small number of foods cause most allergic reactions. Tree nuts are one of the most common triggers. In the mid-1990s, researchers examined a strain of GM soybean that was engineered to contain protein from Brazil nuts. According to their report in the New England Journal of Medicine, the soybeans triggered allergic reactions in people with Brazil nut allergy. Those soybeans never entered the market and aren't sold to consumers. The Food and Agriculture Organization of the United Nations (FAO) and World Health Organization (WHO) have since established protocols for GM foods. They require GM foods to be tested for their ability to cause allergic reactions. According to the Mayo Clinic, none of the GM foods that are currently on the market have been found to have allergenic effects. Antibiotic resistance Antibiotic-resistant bacteria can resist antibiotics, making them hard to kill. According to the CDC, antibiotic-resistant germs infect two million people each year. Those infections kill at least 23,000 people per year. Scientists often modify seeds using antibiotic-resistant genes in the genetic engineering process. Some people wonder if there's a link between these GM foods and rising rates of antibiotic resistant bacteria. No studies have confirmed this claim, but more research is needed. Cancer In 2013, the journal Food and Chemical Toxicology retracted a paper that linked the herbicide Roundup and Roundup-tolerant GM corn to cancer and premature death in rats. Due to concerns about the paper, the journal's editor reviewed the researchers' raw data and the peer-review process. They found the researchers had used too few rats, the specific strain of rats was prone to cancer, and the results were inconclusive. Since then, the paper has been republished in another journal, Environmental Sciences Europe. The controversy surrounding the study's findings has continued. According to the American Cancer Society, more research is needed to assess the potential long-term health effects of GM foods.

ultimate vs proximate research questions

Proximate • 'How' or mechanism (neural, development) • Interesting in their own right • Sometimes important to understand ultimate questions • example: color vision in NW monkeys - only 2 loci code for color-receptive pigments, one is X-linked with 3 alleles (distinct color sensitivities) - 2/3 of females get 3 distinct alleles and have 'normal' color vision - all males get only 2 alleles and are 'color-blind' - consequences for food choice, foraging height, etc Ultimate • 'Why' = historical or functional - historical -- why is the trait this particular way rather than some other way that serves a similar purpose? Evolutionary history of genes. - functional -- what purpose does the behavior serve? What problem does it 'solve'? - adaptive -- does it increase the fitness of those that use the behavior?

List the scientific method step

Purpose/Question: Ask a question. Research: Conduct background research. Write down your sources so you can cite your references. In the modern era, a lot of your research may be conducted online. Scroll to the bottom of articles to check the references. Even if you can't access the full text of a published article, you can usually view the abstract to see the summary of other experiments. Interview experts on a topic. The more you know about a subject, the easier it will be to conduct your investigation. Hypothesis Propose a hypothesis. This is a sort of educated guess about what you expect. It is a statement used to predict the outcome of an experiment. Usually, a hypothesis is written in terms of cause and effect. Alternatively, it may describe the relationship between two phenomena. One type of hypothesis is the null hypothesis or the no-difference hypothesis. This is an easy type of hypothesis to test because it assumes changing a variable will have no effect on the outcome. In reality, you probably expect a change, but rejecting a hypothesis may be more useful than accepting one. Experiment Design and perform an experiment to test your hypothesis. An experiment has an independent and dependent variable. You change or control the independent variable and record the effect it has on the dependent variable. It's important to change only one variable for an experiment rather than try to combine the effects of variables in an experiment. For example, if you want to test the effects of light intensity and fertilizer concentration on plant growth rate, you're really looking at two separate experiments. Data/Analysis Record observations and analyze what the data means. Often, you'll prepare a table or graph of the data. Don't throw out data points you think are bad or that don't support your predictions. Some of the most incredible discoveries in science were made because the data looked wrong! Once you have the data, you may need to perform a mathematical analysis to support or refute your hypothesis. Conclusion Conclude whether to accept or reject your hypothesis. There is no right or wrong outcome to an experiment, so either result is fine. Note accepting a hypothesis does not necessarily mean it's correct! Sometimes repeating an experiment may give a different result. In other cases, a hypothesis may predict an outcome, yet you might draw an incorrect conclusion. Communicate your results. The results may be compiled into a lab report or formally submitted as a paper. Whether you accept or reject the hypothesis, you likely learned something about the subject and may wish to revise the original hypothesis or form a new one for a future experiment.

Give examples of sources of radiation to people, what is the unit for measuring radiation?

Rates of emission • Becquerel (Bq) - SI unit describing activity related to the decay of 1 nucleus per second. • The average human experiences 4400 becquerels from decaying potassium within the body

Define renewable energy (contrast with fossil fuels).

Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. a natural fuel such as coal or gas, formed in the geological past from the remains of living organisms.

Draw the carbon cycle, including the reservoirs of carbon and fluxes between them. Know the order of magnitude of the size of each reservoir and rate of each flux

STUDY THIS ONEEEEEE

Compare the trade offs (pros and cons) or each

Solar Advantages -Renewable -Technology available Disadvantages -High capital cost -Land use -Not constant supply -Limited materials for construction? -Geographically limited; Storage batteries The big biofuels problems (1) Drive deforestation Only renewable when not overharvested with rapid deforestation, soil erosion, and forest fail to regrow, biomass is frequently not replenished (2) Limited supply Require large land areas is there really enough supply? (3) Competing demands for land and water The agriculture problem and higher food prices (4) Cost Can increase price relative to traditional gasoline/diesel Hydropower Pros -Abundant energy -Mature technology -No greenhouse gases? Cons -Mostly developed in US, Europe -Greenhouse gases? -Environmental damage (for fish, communities, etc.) Pros and cons of wind Advantages Renewable No direct CO2 emissions Technology available The problems Land use & environmental consequences Not constant supply High capital cost

Describe the major renewable energies discussed in class

Solar energy Hydropower Geothermal Wind Biofuels

What does 'at steady state' mean for an element in an ecosystem?

Steady state: in a system, when input equals output, it is said to be in a steady state

Why is N2 not a greenhouse gas?

Such as N2 and O2 and mono atomic molecules (single atomic molecules)such as argon (Ar) have no net change in the distribution of their electrical charges,when they vibrate and hence are almost totally unaffected by infrared radiation. Although molecules containing two atoms of different elements such as carbon monoxide(CO)or hydrogen chloride(HCl) absorb infrared radiation, these molecules are short-lived in the atmosphere owing to their reactivity and solubility. Therefore, they do not contribute significantly to the greenhouse effect and usually are omitted when discussing greenhouse gases.

What is a terminator seed?

Terminator technology is the genetic modification of plants to make them produce sterile seeds. They are also known as suicide seeds. Terminator's official name - used by the UN and scientists - is Genetic Use Restriction Technologies (GURTs)

Consider energy sources to a community; and how energy flows in that community between primary producers/autotrophs (plants), first level consumers (herbivores), and higher level consumers (carnivores)

The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10 percent of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat

How does the theory of island biogeography work? What two factors influence the number and types of species in a community?

The theory predicts other things, too. For instance, everything else being equal, distant islands will have lower immigration rates than those close to a mainland, and equilibrium will occur with fewer species on distant islands. Close islands will have high immigration rates and support more species. By similar reasoning, large islands, with their lower extinction rates, will have more species than small ones -- again everything else being equal (which it frequently is not, for larger islands often have a greater variety of habitats and more species for that reason). There are two general relationships to remember: 1) Immigration is higher on near islands than on distant islands (in relation to the mainland), hence the equilibrium number of species present will be greater on near islands. 2) Extinction is higher on small islands than on larger islands, hence the equilibrium number of species present will be greater on large islands.

Think about experimental design in determining if species is the "keystone" to an ecosystem

Thus, you could work out the keystone species in an ecosystem by sampling population size and and what size 'effect' the removal of the species from the ecosystem would have. If you standardised the units of 'effect' for all species in the ecosytem, the keystone species would be those with the highest effect/population fraction. I don't know if there's a critical size of this fraction for a species to be determined 'keystone', but if there is it would allow you to explicitly define a keystone species. This would rule out the problem of interdependency as you mention.

Understand (from our assignment) how in a top-down trophic cascade primary consumers can still impact secondary consumers

Trophic cascade in Alaska resulting in inverse patterns in abundances or biomass across trophic links in a food web

Describe the three types of survivorship curves and relate these back to reproductive strategies

Type I or convex curves are characterized by high age-specific survival probability in early and middle life, followed by a rapid decline in survival in later life. They are typical of species that produce few offspring but care for them well, including humans and many other large mammals. Type II or diagonal curves are an intermediate between Types I and III, where roughly constant mortality rate/survival probability is experienced regardless of age. Some birds and some lizards follow this pattern. Type III or concave curves have the greatest mortality (lowest age-specific survival) early in life, with relatively low rates of death (high probability of survival) for those surviving this bottleneck. This type of curve is characteristic of species that produce a large number of offspring (see r/K selection theory). This includes most marine invertebrates. For example, oysters produce millions of eggs, but most larvae die from predation or other causes; those that survive long enough to produce a hard shell live relatively long.

Theoretically where should the carbon be going and what are some reasons why this is not likely? What are the ecosystem consequences?

What are reasons it could not work? • Ocean currents (move Fe) • Other nutrients are limiting • Algae decompose and re-release CO2 back before reach deep sea • Algae are eaten by other animals that late die, decompose release CO2 back What are the ecological consequences? • Oxygen depletion • Ecological shifts to harmful algae • Microbial shifts results in production of other harmful greenhouse gases • Disruption/changes to higher trophic levels Many unknowns: • Negative: blue ocean turned green • Positive: more productive fisheries? By design: ocean fertilization changes ecology

What is land subsidence?

a gradual settling or sudden sinking of the Earth's surface owing to subsurface movement of earth materials.

define hypothesis

a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

What is the Haber-Bosch process? What steps does it replace in the nitrogen cycle?

artificial N2 fixation • N2 + 3 H2 → 2 NH3 • A reaction using a metal catalyst under high temperatures and pressures • Hydrogen source - methane gas

Define isotope

atoms with the same number of protons but different number of neutrons

Discuss/draw how humans are influencing the nitrogen cycle, including N2O and NO3

dissolving of nitrogen oxides discharge of municpal sewage detergents natural ruynoff construction runoff

What are some of the pros and cons of this process?

eer review has been defined as a process of subjecting an author's scholarly work, research or ideas to the scrutiny of others who are experts in the same field. It functions to encourage authors to meet the accepted high standards of their discipline and to control the dissemination of research data to ensure that unwarranted claims, unacceptable interpretations or personal views are not published without prior expert review. Despite its wide-spread use by most journals, the peer review process has also been widely criticised due to the slowness of the process to publish new findings and due to perceived bias by the editors and/or reviewers. Within the scientific community, peer review has become an essential component of the academic writing process. It helps ensure that papers published in scientific journals answer meaningful research questions and draw accurate conclusions based on professionally executed experimentation. Submission of low quality manuscripts has become increasingly prevalent, and peer review acts as a filter to prevent this work from reaching the scientific community. The major advantage of a peer review process is that peer-reviewed articles provide a trusted form of scientific communication. Since scientific knowledge is cumulative and builds on itself, this trust is particularly important. Despite the positive impacts of peer review, critics argue that the peer review process stifles innovation in experimentation, and acts as a poor screen against plagiarism. Despite its downfalls, there has not yet been a foolproof system developed to take the place of peer review, however, researchers have been looking into electronic means of improving the peer review process. Unfortunately, the recent explosion in online only/electronic journals has led to mass publication of a large number of scientific articles with little or no peer review. This poses significant risk to advances in scientific knowledge and its future potential. The current article summarizes the peer review process, highlights the pros and cons associated with different types of peer review, and describes new methods for improving peer review.

How do humans use energy? Explain how a power plant moves/transfers energy. More broadly, what steps are needed for energy to get from source to user? How is energy transferred along this process?

energy resource extraction transportation processing combustion disposal/electricity generation electricity transmission user

Which renewable energies cannot be linked to the sun?

geothermal and tidal energy

What are some of the ecosystem services soils perform?

medium for plant growth system for water supply and purification recycling system for nutrients and organic waste modifier of the atmosphere habitat for soil organisms engineering medium

Describe the source of energy for fossil fuels.

natural gas=30% petroleum=37% coal=15% nuclear=9% renewable=10%

Describe trends in energy use by resource over time in the USA and globally.

oil has grown exponentially from 20-70 and stayed since nuclear eneergy grew around the 70s and now natural gas grew from 50-70 and stayed constant coal has fluctuated anf leveled off

How might you incorporation corridors with a changing climate?

project movement

Explain r versus K reproductive strategies

r-selection r-selected species are those that emphasize high growth rates, typically exploit less-crowded ecological niches, and produce many offspring, each of which has a relatively low probability of surviving to adulthood (i.e., high r, low K).[8] A typical r species is the dandelion (genus Taraxacum). In unstable or unpredictable environments, r-selection predominates due to the ability to reproduce quickly. There is little advantage in adaptations that permit successful competition with other organisms, because the environment is likely to change again. Among the traits that are thought to characterize r-selection are high fecundity, small body size, early maturity onset, short generation time, and the ability to disperse offspring widely. Organisms whose life history is subject to r-selection are often referred to as r-strategists or r-selected. Organisms that exhibit r-selected traits can range from bacteria and diatoms, to insects and grasses, to various semelparous cephalopods and small mammals, particularly rodents. K-selection By contrast, K-selected species display traits associated with living at densities close to carrying capacity and typically are strong competitors in such crowded niches that invest more heavily in fewer offspring, each of which has a relatively high probability of surviving to adulthood (i.e., low r, high K). In scientific literature, r-selected species are occasionally referred to as "opportunistic" whereas K-selected species are described as "equilibrium".[8] In stable or predictable environments, K-selection predominates as the ability to compete successfully for limited resources is crucial and populations of K-selected organisms typically are very constant in number and close to the maximum that the environment can bear (unlike r-selected populations, where population sizes can change much more rapidly). Traits that are thought to be characteristic of K-selection include large body size, long life expectancy, and the production of fewer offspring, which often require extensive parental care until they mature. Organisms whose life history is subject to K-selection are often referred to as K-strategists or K-selected.[9] Organisms with K-selected traits include large organisms such as elephants, humans, and whales, but also smaller, long-lived organisms such as Arctic terns,[10] parrots and eagles.

Explain the process of alpha emission, beta emission and electron capture

• Alpha emission: loss of a 4He (2n, 2p) • Beta emission: neutron - electron → proton • Electron capture: proton + electron → neutron

How does the flow of energy and matter in ecosystems differ?

• Matter moves between ecosystems, biotic & abiotic environments • Unlike energy

Define radionuclide

• Radionuclide • Atom with an unstable nucleus