Effects of human activities on earth

Which human activity would preserve nonrenewable resources?

• deforestation
• removing carnivores from a forest 
• recycling
• heating homes with fossil fuels  

Continued depletion of the ozone layer will most likely result in

• an increase in skin cancer among humans 
• a decrease in atmospheric pollutants 
• an increase in marine ecosystem stability 
• a decrease in climatic changes

The acidity of a local stream would most likely be affected by

• a change in the percentage of decomposers living in the stream
• a new source of air pollution 
• a new predator species being introduced to the ecosystem
• a decrease in the amount of sunlight that reaches the stream

Increased industrialization will most likely

• decrease available habitats 
• increase environmental carrying capacity 
• increase the stability of ecosystems 
• decrease global warming

Which human activity is correctly paired with its likely future consequence?

• overfishing in the Atlantic — increase in supply of flounder and salmon as food for people 
• development of electric cars or hybrid vehicles — increased rate of global warming 
• use of fossil fuels — depletion of underground coal, oil, and natural gas supplies 
• genetically engineering animals — less food available to feed the world’s population

Which human activity would most likely deplete nonrenewable resources?

• use of natural enemies to eliminate insect pests
• development of wildlife refuges 
• governmental restriction of industrial pollution 
• increased use of fossil fuels

Deforestation of areas considered to be rich sources of genetic material could limit future agricultural and medical advances due to

• the maintenance of dynamic equilibrium 
• the loss of biodiversity 
• an increase in the ecosystem’s carrying capacity
• the depletion of the ozone layer

Deforestation by burning has been described as a "double whammy" to the environment, meaning it has 2 negative impacts. Why is this description accurate? 

• Forest burning releases CO₂ while decreasing oxygen, which disrupts cycles
• Deforestation reduces the amount of oxygen in the atmosphere, which depletes the ozone layer
• Forest clearing is often followed by land development, which often leads to increased noise pollution
• Deforestation increases the number of plant and animal species by destroying habitat

Approximately 75 percent of the Earth's surface is covered in water. So why is water considered such a precious resource?

• The greenhouse effect is causing most of the world's freshwater to be trapped in the atmosphere
• Only a small fraction of the Earth's water is freshwater available for drinking and irrigation
• Each year, more freshwater is being trapped in icecaps located at the North and South Poles
• Global warming caused by greenhouse gas emissions will likely cause Earth's oceans to evaporate

Many common products, such as wooden furniture, paper, and books, are made from trees. Which of the following is a likely consequence of humans cutting down a forest in order to make use of the natural resources there? 

• the decrease of chemical runoff into the oceans
• increased acid rain
• the increase of light pollution in cities
• the destruction of habitats