Semester 1 Slides.pptx

Ecosystem Boundaries and Species Interactions

Learning Goals Overview

  • Learning Goals 1-1 through 1-5: Several goals revolve around understanding ecosystem boundaries, species interactions, resource competition, and invasive species.

LG 1-1: Ecosystem Boundaries

  • Ecosystem boundaries can be defined by both abiotic (e.g., temperature, salinity) and biotic factors (e.g., types of organisms present).

  • Communities of organisms interact dynamically within these boundaries, which can vary significantly in size.

LG 1-2: Competing Species and Resource Response

  • Limited resources lead to competition among species, influencing their survival and adaptations.

  • The competitive exclusion principle asserts that two species competing for the same resource cannot coexist indefinitely.

  • Resource partitioning evolves as a strategy where competing species divide resources through adaptations in behavior or morphology.

  • Examples include how Darwin's finches evolved different beak shapes based on available food resources.

LG 1-3: Consumptive Interactions

  • Interactions such as predation occur when one species consumes another; notable examples include wolves hunting moose.

  • Parasitism involves organisms living on or in a host, causing varying levels of harm without inevitably killing the host.

  • Herbivory refers to plant consumption by animals, which can have ecosystem-wide impacts, including potential collapses when herbivore populations skyrocket.

LG 1-4: Mutualistic Interactions

  • Not all interactions are detrimental. Mutualism benefits both species, such as interactions between plants and pollinators (e.g., birds, bats).

  • Interactions can also result in commensalism, where one species benefits while the other is unaffected (e.g., fish using coral reefs for shelter).

LG 1-5: Invasive Species Interactions

  • Invasive species introduce novel interactions into ecosystems, often competing aggressively and displacing native species.

  • Examples include honeybees in North America and red foxes in Australia, which highlight human-induced changes to native ecosystems.

Terrestrial Biomes and Climate Diagrams

Learning Goals Overview

  • Learning Goals 2-1 through 2-4 focus on defining biomes, interpreting climate diagrams, identifying terrestrial biomes, and understanding the causes of changes in biome boundaries.

LG 2-1: Terrestrial Biomes Definition

  • Terrestrial biomes are classified according to dominant vegetation types, annual temperatures, and precipitation.

LG 2-2: Climate Diagrams

  • Climate diagrams are graphical tools showing monthly temperature and precipitation patterns, helping to ascertain potential biomes.

LG 2-3: Major Terrestrial Biomes

  • The nine major biomes include: Tundra, Taiga, Temperate Rainforest, Temperate Seasonal Forest, Shrubland, Temperate Grassland, Tropical Rainforest, Savanna, and Hot Desert.

LG 2-4: Changing Biome Boundaries

  • Climate change and anthropogenic influences can dramatically alter the boundaries of terrestrial biomes, affecting the distribution and survival of species.

Aquatic Biomes Overview

Learning Goals Overview

  • Learning Goals 3-1 through 3-2 outline identification of freshwater and marine biomes as well as understanding their characteristics.

LG 3-1: Major Freshwater Biomes

  • Freshwater biomes encompass streams, rivers, lakes, and wetlands, characterized by low salinity.

  • Key definitions:

    • Rivers/Streams: Flowing water systems where speed, slope, and volume influence ecosystem characteristics.

    • Lakes/Ponds: Standing water bodies divided into zones (littoral, limnetic, profundal, benthic).

LG 3-2: Marine Biomes

  • Marine ecosystems consist of saltwater environments like estuaries, coral reefs, and the open ocean, each supporting diverse organisms adapted to their unique conditions.

Nutrient Cycling in Ecosystems

Learning Goals Overview

  • Learning Goals 4-1 through 4-2 focus on carbon and nitrogen cycles in ecosystems.

LG 4-1: Carbon Cycling

  • The carbon cycle moves carbon among the atmosphere, land, and ocean, involving processes such as photosynthesis and respiration.

  • Human activities, particularly fossil fuel combustion, lead to a surplus of carbon in the atmosphere, contributing to global warming.

LG 4-2: Nitrogen Cycling

  • The nitrogen cycle involves processes such as nitrogen fixation, consumption by organisms, ammonification, and denitrification, ensuring the availability of nitrogen, a crucial nutrient.

Biodiversity and Ecosystem Health

Learning Goals Overview

  • Learning Goals 8-1 through 8-4 cover biodiversity at different scales and its implications for environmental stressors and estimates.

LG 8-1: Biodiversity Scales

  • Biodiversity includes genetic, species, habitat, and ecosystem diversity which collectively contribute to ecosystem resilience and health.

LG 8-2: Biodiversity and Environmental Stressors

  • Increased biodiversity often enhances ecosystems' stability and response to disturbances.

LG 8-3: Calculating Biodiversity

  • Species richness and evenness are key metrics in assessing biodiversity health.

LG 8-4: Estimating Species Counts

  • Estimations for global species range from 5 million to over 100 million due to the challenges in identifying and accounting for all species.

Ecosystem Services

Learning Goals Overview

  • Learning Goals 9-1 and 9-2 relate to ecosystem services and human impacts on those services.

LG 9-1: Ecosystem Service Categories

  • Ecosystem services comprise four main categories: provisioning, regulating, supporting, and cultural.

LG 9-2: Disruption to Services

  • Human activities such as habitat destruction potentially disrupt ecosystem functions, leading to decreased biodiversity and service availability.

Geological Concepts and Earth Layers

Learning Goals Overview

  • Learning Goals 19-1 through 19-3 focus on geological events, plate tectonics, and the composition of Earth.

LG 19-1: Earth Layers

  • The Earth comprises several layers: core, mantle, and lithosphere, each varying in composition and properties.

LG 19-2: Plate Movement

  • Tectonic plate movements are responsible for geological features and events including earthquakes, volcanoes, and mountain formation.

Agricultural Practices and Environmental Impact

Learning Goals Overview

  • Learning Goals 25-1 through 25-5 address changes in agricultural methods and their environmental implications.

LG 25-1: Historical Changes in Agriculture

  • Progressions in agricultural practices demonstrate shifts from subsistence farming to modern industrial agriculture (the Green Revolution).

LG 25-2: Benefits and Consequences of Green Revolution

  • While the Green Revolution increased food production, it also led to environmental degradation, increased reliance on chemicals, and biotic homogenization.

LG 25-3: GMOs and Sustainable Practices

  • GMOs offer potential benefits but raise concerns regarding ecological impacts and human health risks.

LG 25-4: Mechanization and Fossil Fuels

  • Mechanized agricultural practices have led to energy subsidies in farming, heavily utilizing fossil fuels.

Urbanization and Environmental Challenges

Learning Goals Overview

  • Learning Goals 30-1 and 30-2 cover urbanization impacts on the environment and methods to mitigate urban runoff.

LG 30-1: Urbanization Effects

  • Urban sprawl and increased population density in cities strain local resources and ecosystems, leading to issues like habitat loss and pollution.

LG 30-2: Urban Runoff Mitigation

  • Strategies to address urban runoff involve reducing impervious surfaces and enhancing green infrastructure to improve water infiltration.

Sustainability and Environmental Indicators

Learning Goals Overview

  • Learning Goals 32-1 and 32-2 focus on defining sustainability and understanding environmental indicators.

LG 32-1: Sustainability Definition

  • Sustainability emphasizes resource use that does not compromise future generations' needs.

LG 32-2: Environmental Indicators

  • Key indicators such as biodiversity loss, food production rates, CO2 levels, and water availability offer insights into ecological health.