Environmental Science Chapter 11

What is a functional group?

A group of species that carry out the same functions in an ecosystem (producers and herbivores are two functional groups, for example). (p. 256)

What is desertification?

Desertification is the process in which land is converted into a more desert-like ecosystem through an overutilization of its resources. (p. 264)

How does the degree of isolation of an area affect species richness?

The more isolated an area is (such as an island far off the coast, a tall mountain, or a wetland in the middle of a group of forests), the less likely it is that individuals of a particular species will be able to successfully colonize that area. This means that the more isolated an area is, the more likely it is that the species richness in that area is lower.

What are "in situ" vs "ex situ" approaches to conserving species?

"In situ" approaches are those that focus on managing existing populations or establishing new ones in the wild. "Ex situ" approaches are those where species are maintained temporarily under artificial conditions. (p. 279)

What is the annual estimated total value of NCP or ecosystem services to humans according to ecologists, geographers, and economists (as of 2011)?

125 trillion dollars per year. The world gross domestic product (GDP) was about 87 trillion dollars in 2019.

1: What are four characteristics of species most likely to go extinct? 2: What are four characteristics of species least likely to go extinct?

1: An example of a species that is most likely to go extinct will primarily have small populations, be found in a small area, occupy a specialized niche, and have a low reproductive rate. 2: An example of a species that is least likely to go extinct will have at least one large population, be found over a large area, occupy a generalist niche, and have a high reproductive rate. (p. 277-78)

1: What does it mean when a habitat is degraded (habitat degradation)? 2: How does habitat degradation relate to habitat loss?

1: When a habitat is degraded, it means that its quality is reduced. A degraded habitat no longer supports the same species and/or number of individuals of the original species that it once did. 2: Habitat loss and degradation often go hand-in-hand. For example, the removals of trees from a forest can cause faster water runoff and soil erosion which can negatively impact neighboring ecosystems. The original forest ecosystem is lost, and the neighboring ecosystems are degraded. Side note: Habitat degradation is not always related to habitat loss in cases such as pollution, invasive species, climate change, and habitat fragmentation. (p. 268)

1: What is an introduced species? 2: Why are some species introductions intentional? How are some unintentional? 3: What does it mean when an introduced species escapes?

1: An introduced species is one that has been transported to a location that is outside of its native range. 2: Some species introductions are intentional for the sake of improving the stability of ecosystems or meeting human interests. Conversely, other introductions are unintentional, resulting from various different transportation pathways (for example, some marine invertebrates being transported unknowingly in the ballast water in cargo ships' hulls, or when insects such as aphids and scale insects are transported on the plants they feed on). 3: When a species that has been intentionally introduced to a specific area and then spreads to surrounding areas, that species has "escaped". The term escape covers a variety of situations that differ in the degree of human involvement; they could result from unforeseen events, such as a flood that washes introduced plants from a pond into a river, or from the actions of a landowner who throws weeds from their yard into a neighboring stream. Other organisms just take advantage of new human transport infrastructures, or "corridors", such as canals that link ocean basins or oceans and lakes. (p. 272)

2: What is aquaculture? 3: What are some problems associated with aquaculture?

1: Aquaculture is thought of as one possible solution to the problems of overexploiting aquatic species. In aquaculture, fish or invertebrates are grown in cages or pens and provided with the necessary food and structures they need to grow. Shrimp, oysters, mussels, and fish like salmon, trout, and tilapia are raised this way. 2: One problem associated with aquaculture is that raising animals in such concentrated settings results in increased nutrients in the water from uneaten food and wastes. In marine ecosystems this can cause local algal blooms that negatively affect other fisheries, such as shellfish. On land, runoff can cause similar problems in local bodies of water if the nutrient-rich water is released without proper treatment. Another issue is that that species being farmed may not be native to that area, and if they are unintentionally released into the larger environment, they may become an invasive species. If those species are native, they may still have different genetics than wild populations and may alter the genetic makeup of the wild populations. Lastly, the conversion of wild ecosystems to aquaculture often involves the conversion of natural ecosystems such as mangroves and wetlands, which results in the loss of biodiversity.

1: What are endangered species? 2: What are threatened species?

1: Endangered species are those that have such small numbers that they are in immediate danger of becoming extinct. 2: Threatened species are those that could become extinct if a critical factor in their environment changes. (p. 280)

1: What is habitat fragmentation? 2: How does habitat fragmentation cause an increased amount of edge habitats? How do these habitats harm some organisms? 3: What are some strategies to reduce the impacts of habitat fragmentation?

1: Habitat fragmentation is the process in which habitats are broken down into smaller, isolated patches of land, usually as a result of human activity. 2: Smaller habitat fragments have more edge relative to their area compared to larger habitats. The organisms that live in these edge habitats are exposed to more organisms from neighboring habitats, altering interactions between organisms such as predation, parasitism, and competition. 3: The most obvious way to prevent habitat fragmentation is to just keep habitats intact. However, this is not always possible. The next best thing to do is to just keep habitat fragments as large as possible to minimize the creation of edge habitats. An additional strategy is to provide habitat corridors, which are stretches of land that connect habitat fragments. Fish ladders, hedgerows in agricultural landscapes, and highway overpasses/underpasses are examples of habitat corridors. Lastly, proper planning can be used to minimize the number of roads, power lines, and other features that divide habitats can reduce the degree of fragmentation. (p. 268-69)

1: What are habitats? 2: When does habitat loss occur?

1: Habitats are the physical, chemical, and biological systems that support living things. 2: Habitat loss occurs when natural or human activities damage and destroy habitats to such an extent that they are no longer capable of supporting the species and communities that naturally occur there. (p. 262)

1: What is the general relationship between biodiversity and ecosystem functioning? 2: How does biodiversity affect ecosystem functioning in this way (explain 3 ways)?

1: In general, the higher the number of species in an ecosystem, the better that ecosystem will function. 2: Higher levels of biodiversity means a higher chance of there being species capable of utilizing resources or carrying out particular processes more effectively. Additionally, higher levels of biodiversity also means a greater number of species that use resources in different ways, allowing for a more thorough utilization of resources and less competition. Lastly, biodiversity makes ecosystems more stable and resistant to disturbances. (p. 259)

1: What information needed to protect and manage a rare or endangered species? 2: How do scientists gather this information?

1: Information about the ecology of the species, the status of its populations, and the processes that affect population sizes and distribution is needed. 2: -Scientists can conduct a census (inventories or surveys) on a species and monitor it over time. Repeated censuses allow scientists to assess changes in the population size of a species and how the population responds to changes in the environment. -Scientists can also conduct demographic studies, in which known individuals of a population are followed over time so that information such as rates of growth, reproductions, survival, and the percentage of adults that breed in a given season can be gathered. (p. 280)

What are some species-level approaches to preserving biodiversity?

1: Listings and legal listings, such as the IUCN Red List, the ESA, and CITES. 2: Population Assessments and management. 3: Establishing new populations. (p. 279-81)

1: What are NCP, or nature's contributions to people? 2: What organization defined these?

1: NCP are the ways in which nature enriches human life, provides useful resources (building materials, medicine, food, etc.), makes life on Earth more comfortable, and harms people (diseases, predators attacking people or livestock, etc.). NCP provides a way to understand and recognize the contributions, both positive and negative, of living nature to people's quality of life. 2: The intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) defined these NCP. For reference, here are the 18 NCP defined by IPBES: 1: Habitat creation and maintenance. 2: Pollination and dispersal of seeds and other propagules. 3: Regulation of air quality. 4: Regulation of climate. 5: Regulation of ocean acidification. 6: Regulation of freshwater quantity, location, and timing. 7: Regulation of freshwater and coastal water quality. 8: Formation, protection, and decontamination of soils. 9: Regulation of hazards and extreme events. 10: Regulation of detrimental organisms and biological processes. 11: Energy. 12: Food and feed. 13: Materials and assistance. 14: Medicinal, biochemical, and genetic resources. 15: Learning and inspiration. 16: Physical and psychological experiences. 17: Supporting identities. 18: Maintenance of options. (p. 257-58)

What are some ecosystem/landscape-level approaches to preserving biodiversity?

1: Protecting areas either through government designation and management (such as national or state/provincial parks) or private investment (such as land trusts and conservancies). 2: Ecological restoration. Ecological restoration is the restoration of lost or degraded ecosystems. More specifically, restoration is the return of an ecosystem to its original state, while rehabilitation improves a system relative to its degraded state. 3: Regional ecosystem planning. (In order to balance human interests and needs with ecosystem stability.) (p. 281-84)

What are two techniques for managing the populations of endangered species?

1: Removing or reducing populations of invasive species that are outcompeting or preying upon a threatened species. 2: Supplementing limiting resources in degraded habitats or reintroduction sites. (p. 280)

1: What is species diversity? 2: How does it account for the potentially flawed picture of biodiversity that can be painted from only taking species richness into account? 3: Why is measuring species richness often focused on instead of species diversity?

1: Species diversity is the number -and- evenness of species. 2: Species richness only accounts for how many different species there are in an ecosystem, not the distribution and number of members of each species, while species diversity account for both of these aspects. This paints a more complete picture of biodiversity. 3: Measuring species diversity is often challenging. (p. 256)

1: How did American entomologist Terry Erwin famously estimate the number of species on Earth in the early 1980's? 2: What is the more recent estimation scientists have made?

1: Terry Erwin sprayed pesticides in the canopies of tropical rainforest trees in Panama. He collected over 1,200 species of beetles, 162 of which were only found in the canopies of one tree species. He assumed that each tree species must have a similar number of unique beetle species. He then took into account how many tree species were estimated to be on Earth and the fact that beetles are the most common type of insect (the largest animal group) at 40% of all species. From this information, he determined that there must be around 30 million species on Earth. 2: Using similar methods to Terry Erwin, scientists have since estimated that there are between 1 and 6 billion different species on Earth (~2.2 million have been identified so far). Other scientists, using data on patterns of bacterial diversity, have estimated that there are roughly 1 trillion species on Earth. (p. 253)

1: What is the ESA? 2: What does it do? 3: What government agencies are responsible for the administration of the ESA?

1: The ESA is the U.S. Endangered Species Act of 1973. 2: The ESA designates species as endangered or threatened and gives the federal government jurisdiction over any species designated as endangered. 3: The U.S. Fish and Wildlife Service and the National Marine Fisheries Service are responsible for the administration of the ESA. (p. 280)

1: What is the leading global organization in assessing the statuses of species? 2: What are the three threat categories that this organization recognizes? 3: How many species are threatened with extinction according to the Red List of threatened species that is managed by this organization?

1: The IUCN. 2: Critically endangered, endangered, and vulnerable. 3: 31,000 species are listed as threatened on the IUCN Red List. These species include 41% of amphibians, 25% of mammals, 14% of birds, 30% of sharks and rays, and 33% of corals. (p. 279)

1: What factors determine species richness in an ecosystem? 2: Of these, which two are most important? 3: What are some more specific factors that determine species richness in aquatic ecosystems?

1: The factors that determine species richness in an ecosystem are: the availability of energy and water, the geologic and evolutionary history of a region, the size of an area, and the degree of isolation of an area. 2: The two most important factors are the availability of energy and water. 3: In aquatic ecosystems, the temperature is more consistent and the availability of water is of course not an issue. More specific factors that determine species richness in aquatic environments are: the chemical characteristics of the environment such as salinity or acidity, the temperature of the water, and the flow of the water (the types of organisms present can vary in a still pond and a turbulent river). (p. 253)

1: What is the ultimate source of energy for every organism on Earth? 2: This source of energy is unevenly distributed across the Earth. How does this uneven distribution influence species richness in different environments?

1: The sun is the ultimate source of energy for life on Earth. 2: Sunlight is unevenly distributed across the surface of the Earth. This uneven distribution results in an uneven heating of the Earth's surface, which means that the rainfall patterns, availability of water on land, and ocean currents in different environments will vary drastically, directly influencing the distribution of energy and water available to organisms. This is the reason why there is a latitudinal gradient in diversity on Earth, with many more species being found near the equator in tropical environments (more energy and freshwater from rain is available). (p. 253)

What is a protected area according to the IUCN?

According to the IUCH, a protected area is a clearly defined geographical space, recognized, dedicated, and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values. (p. 281)

What is the option value of nature perspective on the importance of biodiversity?

According to this perspective, maintaining existing biodiversity is valuable because it is impossible to predict which aspects will help maintain the stability and integrity of natural systems in a human-dominated and rapidly changing world. In other words, maintaining biodiversity gives humans the greatest number of options moving forward. Species that may go extinct now may have been the source of a discovery that would have benefitted humans in the future. (p. 260)

What is the leading cause of terrestrial habitat loss?

Agricultural land conversion. Currently, about 50% of habitable land and nearly 75% of freshwater resources are devoted to agriculture. Side note: Of that agricultural land, 23% is devoted to crop production, while 77% is devoted to raising livestock. (p. 263)

How many species are described on average annually?

Almost 18,000. (p. 252)

What is an invasive species?

An invasive species is an introduced species which becomes established in its new environment, starts to spread, and begins to harm native species, environments, and/or human wellbeing.

What are inventories vs surveys?

An inventory is a count of the total number of individuals in a population. A survey is the use of a repeatable method to sample a portion of the population, and then estimate the number of individuals or the density of a population from the survey data. These methods can be techniques such as mark-recapture methods for mobile organisms, or transects and quadrats for nonmobile organisms. (p. 280)

What are strategies to minimize the amount of habitat loss due to agricultural land conversion?

Better practices and technologies that increase the productivity of existing agricultural land can be employed. New methods of irrigation, crop rotation, and harvesting, as well as new crop varieties, can improve the productivity of the land already converted to agriculture. Additionally, the small patches of natural ecosystems left inside and around agricultural regions can be preserved. These patches can be valuable for maintaining native organisms and to act as important sources for predators and parasites of agricultural pest insects (consequentially increasing crop yields). Lastly, practices that allow agricultural areas to more closely mimic natural vegetation can be used. (p. 264)

What is bio-prospecting?

Bio-prospecting is the process of looking for potentially valuable genetic resources and biochemical compounds in nature. (p. 250)

What is biodiversity?

Biodiversity is the variety of living things. It includes variation in the number of genes, populations, species, and ecosystems and how they function, as well as the diversity of evolutionary histories they represent. (p. 251)

What is biotic homogenization?

Biotic homogenization is the process in which specialist species are replaced by generalist (and usually nonnative) species as a result of human alteration of the environment. (p. 278-79)

What is bycatch?

Bycatch refers to all of the other organisms captured along with the species being targeted. (p. 271)

What is CITES?

CITES stands for the Convention on International Trade in Endangered Species of Wild Fauna and Flora. It is an international agreement among governments of 170 countries. CITES aims to ensure that international trade in wild animals and plants does not threaten their survival. Countries agree to limit the export and import of certain species to protect the populations in their countries of origin. There are about 5,000 species of animals and 29,000 species of plants that are protected by CITES against overexploitation through international trade. (p. 280)

Why is categorizing ecoregions helpful?

Each ecoregion is described by its relatively distinct species. Each ecoregion is unique to a place, so categorizing them provides a way to estimate the overall diversity of ecosystems. Categorizing ecoregions also provides an important conservation planning tool to monitor changes in the size of each ecoregion in the face of threats to biodiversity such as habitat loss and degradation, and to target conservation actions such as designating protected areas or pursuing other policy initiatives. (p. 255)

What factor does ecosystem diversity depend on?

Ecosystem diversity depends on the scale of the area in question. The larger the area, the more distinct ecoregions that area will contain. (p. 255)

What is ecosystem diversity?

Ecosystem diversity refers to the number of different kinds of ecosystems present in an area. (p. 255)

What are some strategies to minimize overexploitation?

Exploited species could be monitored and the their harvest could be regulated to ensure long-term sustainable use. Additionally, alternative sources of organisms could be found to meet human needs such as food, materials, and energy. Many additional solutions can be applied to specific cases of overexploitation. For instance, fish hooks could be redesigned to decrease the chances of capturing and killing sea turtles. Similarly, gill nets could be designed with beacons to warn whales, and weak links to allow large whales to break free. (p. 272)

What is the perspective of phylogenetic diversity on biodiversity?

From the perspective of phylogenetic diversity, the loss of a species or group of species that is more closely related to species that still persist may have a smaller long-term impact than the loss of a unique or different evolutionary lineage. (p. 256)

What is functional diversity?

Functional diversity refers to the diversity of the functions that organisms can carry out. (p. 256)

"Biodiversity is the variability among living organisms from all sources, including terrestrial, marine and other aquatic ecosystems, and the ecological complexes of which they are a part. This includes variation in genetic, phenotypic, phylogenetic, and functional attributes, as well as changes in abundance and distribution over time and space within and among species, biological communities and ecosystems." According to this formal definition of biodiversity provided by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), biodiversity can be looked at by counting up the number of difference types (or variants) at various levels of a hierarchy. What are the levels of this hierarchy?

Genes within populations, populations within species, species within communities and ecosystems, and ecosystems within landscapes and the overall biosphere. (p. 252)

What does genetic diversity refer to?

Genetic diversity refers to the number of different types or variants of DNA present within a population, species, or community. (p. 254)

What are global extinctions vs local extinctions?

Global extinction occurs when no member of a species remains alive anywhere in the world. A local extinction occurs when a species is no longer found in an area it once inhabited but still lives elsewhere. A global extinction is the extinction of a species, while a local extinction is the extinction of a population of a species. (p. 277)

What are habitat islands?

Habitat islands are "islands" in a "sea" of other habitats. An example would be a wetland in the middle of an expansive forest. Species that would typically thrive in a wetland habitat would have a hard time traveling through the forest to reach the wetland and populate it. (p. 253)

What is habitat management?

Habitat management is the strategy of making alterations to a habitat to help a species to succeed. (p. 281)

What is horizontal gene exchange?

Horizontal gene exchange is the direct exchange of genetic material between bacteria. (p. 252)

What does it mean if two or more problems are synergistic?

If two or more problems are synergistic, the total harm done by all of them is greater than the harm that would be done by each on their own. (p. 277)

What steps does land reclamation typically include?

Land reclamation typically involves stabilizing the terrain, removing machinery and filling in pits, removing pollutants, ensuring public safety, and (usually) reintroducing vegetation and other aesthetic improvements. (p. 283-84)

Morphology (Biology)

Morphology (in relation to biology) is the study of the form of living organisms, and with relationships between their structures.

What is overexploitation?

Overexploitation occurs when humans use or extract a resource to the point of exhaustion or extinction. Populations are overexploited when humans harvest them faster than they can be replaced.

What is the perspective of functional diversity on biodiversity?

People with this perspective on biodiversity focus on the diversity of the functions carried out, rather than particular species. Measures of functional diversity highlight that not all species are equal in terms of their influence on how ecosystems perform. (p. 256)

What is phylogenetic diversity?

Phylogenetic diversity is a measure of biodiversity accounting for shared evolutionary history. (p. 256)

What is population augmentation?

Population augmentation is the process of releasing individuals of a species into an existing population to increase its size and gene pool. (p. 281)

What are some strategies to reduce the environmental impacts of deforestation?

Reforestation, the use of alternate materials for building and fiber for paper (such as hemp, bamboo, and flax), and the development of tree plantations (tree farms) are some strategies that can be utilized. (p. 266-68)

What is species richness?

Species richness is a measure of the number of different species in a community. (p. 252)

How does the geologic and evolutionary history of a region influence species richness?

The "rougher" the geologic and evolutionary history of a region, the lower the number of species present. This is because regions with a higher availability of energy and resources allows more opportunities for different species to thrive.

What are some countries that mandate the legal protection of endangered and threatened species?

The United States, Canada, Australia, India, South Africa, and Brazil are some of the countries that mandate the legal protection of endangered and threatened species. (p. 279-80)

How does the size of an area affect species richness?

The bigger an area, the higher the degree of variation in habitats, conditions, and resources. This higher degree of variation allows more species to thrive. Conversely, areas with smaller degrees of variation in habitats, conditions, and resources support a more limited range of species.

What is the least genetically diverse species known of?

The channel Island fox. This species of fox is found on several islands off the coast of California. The low level of genetic diversity present in populations of these foxes is due to years of population declines. (p. 254)

How can the economical value of NCP be determined?

The financial value contributed by ecosystem services (NCP) can be determined and compared to the value of unsustainable use. (Think of the free pest control provided to farmers by birds and bats that saves billions of dollars annually. The ecosystem service provided by the birds and bats is of financial value because it saves money for farmers.) (p. 259, review in book)

What are some strategies for minimizing the impacts of invasive species?

The first (and most brutal) strategy is to eradicate the species entirely from the new environment. However, that is usually impossible (there are usually too many individuals and it is too hard to find them all, and plants can exist as root systems or seeds). The second strategy is to manage existing populations and to prevent or at least limit new individuals and species from being introduced. Management techniques include physical, chemical, and biological methods. The last strategy is to simply prevent the introduction of invasive species entirely. One method of doing this is to employ policies and economic incentives to regulate the pathways that species may use to "invade" environments they are not native to. (p. 275-76)

What is the intrinsic value of nature perspective on the importance of biodiversity?

This perspective is based on the idea that people may not need or want to assign a monetary value to nature. Instead, nature has an intrinsic value as well as a fundamental right to exist without its survival being challenged by humans, whether or not it benefits humans directly or indirectly.

Why is a high level of genetic diversity beneficial to a population of an organism?

When there is a high level of genetic diversity in a population, the chances of there being a favorable genetic trait in the population is higher. Side note: It's also important to note that the bigger a population is (and the less isolated it is), the more likely it is that the genetic diversity of that population is high. (p. 254-55)

What is the nonmaterial values perspective on the importance of biodiversity?

While regulating and material NCP may be quantified in monetary terms, the nonmaterial value (learning, inspiration, physical and psychological experiences, identity, spirituality, sense of place) is much harder to describe in these terms. However, this does not change the fact that these nonmaterial values are crucial to the health and happiness of people. (p. 260)