Factors Affecting Earth

If topsoil from a freshly fertilized field was washed into a local stream, nitrogen in the water would drastically increase, causing algae to grow. What effect would this have on the stream?

• Animal life in the stream would benefit since most fish eat algae

• It would upset the balance of carbon dioxide and oxygen in the water, causing fish to die

• The algae would act as a thermal blanket on the stream, causing water temperature to increase

• The algae would attach itself tot he stream bank and narrow the width of the stream.

In a landslide, the tons of rock falling would force animals living in the area to...

• move to a new area

• develop new adaptations

• uncover buried plants

• develop different diets

Which would be a disturbance to a grassland biome?

• a fire caused by lightning

• a hurricane

• a volcanic eruption

• an earthquake

Which is a human activity that uses up a non-renewable resource?

• chopping down trees from the forest

• a car engine consuming large amounts of fossil fuels

• pollutants on the road washing into the streams

• building new roads, causing topsoil to erode

Dumping oil into the soil is hurting the environment because the oil...

• rots the base of wood in fences, attracting harmful insects

• kills weeds, and they are important to the environment

• attracts more insects

• goes deep into the soil and pollutes the groundwater

What is a negative effect that fertilizers have on the environment?

• excess is washed into streams, causing an overgrowth of algae

• it builds up in the soil and causes more weeds to grow

• it evaporates and causes acid rain to fall

• it causes an overabundance of producers

Why should you seal a concrete birdbath with a watertight solution?

• in cold, wet weather, water seeping into the concrete would freeze and cause the birdbath to crack

• the solution would slow the evaporation of water

• over time rainwater would react with the surface of the concrete

• birds like the birdbath shiny

Many people in Texas get their water from underground water that is stored from rain water. What would cause the biggest change on the amount of water available to people?

• long periods without rainfall

• long periods of high temperature

• below-freezing temperatures

• non-porous rocks storing the water

Rivers flow from higher elevations toward lower elevations. Rivers move sediment. When a river is dammed, it will change the sediment flow. Which change would occur?

• the dam will not affect the deposition of the sediment

• more sediment will be deposited behind the dam

• more sediment would be deposited after the dam

• more sediment would move down the river

When a river runs through a valley, and the river has a higher rate of erosion than deposition, how will the topography of the river change?

• The river will have very little change

• The river will have a slight change, causing it to run a little faster

• The river will have a great change, widening as it erodes