The geographically informed person must understand that Earth’s surface is home to multiple biophysical communities. All elements of the environment, including the human, are part of many different but nested ecosystems that comprise different biomes. Ecosystems and biomes, defined by specific plant and animal communities interacting with the physical environment, are unevenly distributed on Earth’s surface.
Therefore, Standard 8 contains these themes: Components of Ecosystems, Characteristics and Geographic Distribution of Ecosystems, and Characteristics and Geographic Distribution of Biomes.
Ecosystems and biomes are integral parts of the biosphere and interact with the atmosphere, hydrosphere, and lithosphere to form areas varying in size, shape, scale, and complexity. An ecosystem, for example, might be as small as a stand of oak trees or a pond or as large and complex as a vast desert or rainforest. Ecosystems that share similar characteristics of climate and vegetation can be grouped together to form regional-scale regions known as biomes. These biomes include Earth’s tropical and temperate forests, savannahs and scrublands, grasslands, deserts, tundra, and oceans.
Changes in one ecosystem can have a ripple effect, with varying degrees of impact, as those changes influence other ecosystems, ultimately affecting the structures of the larger biomes. While ecosystems and biomes create both stability and equilibrium on Earth’s surface, they can be altered by large-scale natural events such as volcanic eruptions, increases in surface temperature, or long-term droughts, or by human interventions such as overgrazing grasslands and clearing rainforests that may occur without an understanding of the environmental consequences.
Knowing how ecosystems and biomes function will enable students to make informed decisions about the sustainable uses of the natural world in the future. Global climate change is a reality with the potential of inflicting unimagined outcomes on the planet. The degree to which present and future generations understand the critical role they must play in maintaining healthy ecosystems and biomes will determine, in large measure, the quality of human life on Earth.
Students must understand how ecosystems and biomes form a fragile web of ecological interdependence. Understanding these themes enables students to appreciate our dependence on ecosystems and biomes and understand how we can live in environmentally sustainable ways.
1. The components of ecosystems
Therefore, the student is able to:
A. Identify the components of different ecosystems, as exemplified by being able to
2. The characteristics of ecosystems
Therefore, the student is able to:
A. Identify and describe the characteristics of ecosystems, as exemplified by being able to
3. The characteristics of biomes
Therefore, the student is able to:
A. Describe the characteristics of biomes, as exemplified by being able to
1. Components of ecosystems are interdependent
Therefore, the student is able to:
A. Describe how the components of ecosystems are connected and contribute to the energy of their own cycles, as exemplified by being able to
B. Construct a model to explain how an ecosystem works, as exemplified by being able to
2. Physical processes determine the characteristics of ecosystems
Therefore, the student is able to:
A. Describe and explain how physical processes determine the characteristics of ecosystems, as exemplified by being able to
3. Climate primarily determines the characteristics and geographic distribution of biomes
Therefore, the student is able to:
A. Describe and explain how climate (temperature and rainfall) primarily determines the characteristics and geographic distribution of biomes, as exemplified by being able to
1. Ecosystems are dynamic and respond to changes in environmental conditions
Therefore, the student is able to:
A. Explain how there are short-term and long-term changes in ecosystems, as exemplified by being able to
B. Explain how local and global changes influence ecosystems, as exemplified by being able to
2. The characteristics and geographic distribution of ecosystems
Therefore, the student is able to:
A. Explain the geographic distribution of ecosystems, as exemplified by being able to
B. Evaluate ecosystems in terms of their biodiversity and productivity, as exemplified by being able to
3. The distribution and characteristics of biomes change over time
Therefore, the student is able to:
A. Explain how climate can influence and change the characteristics and geographic distribution of biomes, as exemplified by being able to