Chapter 6 Humans in the Biosphere Flashcards
Describe monoculture.
the practice of clearing large areas of land to plant a single highly productive crop year after year.This enables efficient sowing, tending, and harvesting of crops using machines
What is a renewable resource?
can be produced or replaced by a healthy ecosystem
What is a nonrenewable resource?
natural processes cannot replenish them within a reasonable amount of time
How can you describe sustainable devolopment?
the use of resources in an environmentally conscious way
How do our daily activities affect the environment?
Humans affect regional and global environments through agriculture, development, and industry in ways that have an impact on the quality of Earth’s natural resources, including soil, water, and atmosphere
What is the relationship between resource use and sustainable development?
Sustainable development provides for human needs while preserving the ecosystems that produce natural resources
Describe desertification.
a combination of farming, overgrazing, seasonal drought, and climate change in areas of the world with dry climates can turn farmland into desert
Describe deforestation.
loss of forests; can have a negative effect on soil quality
What is a pollutant?
a harmful material that can enter the biosphere.When coming from a single source (factory or oil spill) it is called point source pollution.When coming from a variety of sources (automobiles) they are called nonpoint sources.
What is biological magnification?
occurs if a pollutant, such as DDT, mercury, or PCB, is picked up by an organism and is not broken down or eliminated from its body. The concentration of the pollutant when moving up the food pyramid increases by a factory of about 10 at each step.
Describe smog.
a gray-brown haze formed by chemical reactions among pollutants released into the air by industrial processes and automobile exhaust
Why is ozone good at times and bad at times?
good- high up in our atmosphere to help protect life on Earth from ultraviolet radiation.Bad- at ground level (smog) ozone and other pollutants threaten the health of people, especially those with respiratory conditions.
Describe acid rain.
A lower than normal pH of rain water that is made when certain chemicals such as nitrogen and sulfur combine with rain water.
Why is soil important and how do we protect it?
Topsoil can be a renewable resource if it is managed properly. Preventing soil erosion through careful management of both agriculture and forestry.
What are the primary sources of water pollution?
industrial and agricultural chemicals, residential sewage, and nonpoint sources
What are the major forms of air pollution?
Common forms of air pollution include smog, acid rain, greenhouse gases, and particulates
Define Biodiversity.
the total of all the genetically based variation in all organisms in the biosphere
Describe ecosystem diversity.
refers to the variety of habitats, communities, and ecological processes in the biosphere.
Describe species diversity.
the number of different species in the biosphere, or in a particular area
Describe genetic diversity.
the sum of all different forms of genetic information carried by a particular species, or by all organisms on Earth.
Describe habitat fragmentation.
The splitting of ecosystems into pieces (can separate ranges of organisms)
What is an ecological hot spot?
a place where significant numbers of species and habitats are in immediate danger of extinction
Why is biodiversity important?
biodiversity exists on three levels:1) ecosystem diversity2) species diversity3) genetic diversityBenefits to society include contributions to medicine and agriculture, and the provision of ecosystem goods and services.Also, allows life to withstand evolutionary constraints
What are the most significant threats to biodiversity?
humans reduce biodiversity by altering habitats, hunting, introducing invasive species, releasing pollution into food webs, and contributing to climate change.
How do we preserve biodiversity?
we must protect individual species, preserve habitats and ecosystems, and make certain that human neighbors of protected areas benefit from participating in conservation efforts.
What is an ecological footprint?
total area of functioning land and water ecosystems needed both to provide the resources an individual or population uses and to absorb and make harmless the wastes that individual or population generates
How does the average ecological footprint in America compare to the world’s average?
the average American has an ecological footprint over four times larger than the global average
How can ecology guide us toward a sustainable future?
1) recognizing a problem in the environment2) researching that problem to determine its cause3) using scientific understanding to change our behavior to have a positive impact on the global environment
