Water Resources - AP Environmental Science

Shade provided by the riparian zone is crucial to stream temperature regulation.

The riparian zone is the edge of a river or stream, therefore it has high biodiversity due to edge effects. Biofilters in the riparian zone protect the aquatic environment it surrounds. Also, because the riparian zone spans distances of an aquatic environment's edge, it serves as a corridor for wildlife.

The correct response was 10,000 years ago. The Great Lakes formed during glacial recession of the most recent glaciation. This most recent glacial recession occurred between 10-15 thousands years ago. As the glaciers receded northward across North America, melting glacial waters drained and formed what is now known as the Great Lakes.

The correct response is 0.02%. The rest of the water resources are either too salty, too deep, or too cold in frozen icecaps.

Lakes, streams, rivers and ground water account for about a half a percent of the fresh water found on Earth.

It is estimated that roughly 50% of individuals in the United States rely on groundwater for their water supplies. In some countries this percentage approaches 100%.

Agriculture is by far the largest consumer of the usable fresh water on earth, using up roughly 70% of water consumed by humans.

In hydroponics, plants are grown in nutrient-rich water and there is no soil involved in the process. Some water is lost through evaporation, but since it is a closed system, very little water is lost.

Flushing the toilet is the largest contributor to household water consumption, averaging about three gallons of water per flush.

Seventy-five percent of Earth's surface is water, and the oceans contain ninety-seven percent of Earth’s water. This means that roughly three percent of the Earth's water resides in rivers, lakes, glaciers, and water vapor.

The correct response is 97%. The remaining 3% is freshwater.

The correct response is watershed. A watershed is the drainage basin for a particular region. It’s where water collects or drains. It's functions like a funnel. The other answer choices deal with different aspects of water. Estuaries are transition zones between marine and freshwater systems. Deltas are also transition zones where a river dumps sediment into a body of water. And groundwater is not specific to a region - it's just water that is found underneath the soil surface.

The correct response is delta. This is the region where a river meets another body of water. It is a transition zone. Important ecological and biological processes occur in delta regions. One good example of a delta is the Nile Delta where the Nile River meets the Mediterranean Sea.

The correct response is littoral. The littoral layer is the layer in a freshwater lake along the shoreline with shallow water. The limnetic layer represent "open water", so this layer is off the coastline and in the middle of the freshwater lake. The benthic layer is along the bottom of the lake (i.e. benthic = bottom). And the profundal layer is the layer at the bottom of deep lakes where the light can't reach the bottom.

Physics describes the Coriolis effect as "the deflection of a moving object due to a rotating reference frame." When the motion is clockwise, the deflection is to the left. When motion is counterclockwise, the deflection is to the right. Put into context: Earth's major wind patterns dictate ocean currents (the object) for the most part—however, the rotation of the Earth deflects surface currents at an angle of about 45 degrees to the wind. The result is a rightward deflection in the Northern hemisphere, and a leftward deflection in the Southern hemisphere.

Eckman transport is the change in wind direction correlating to altitude due to the varying effect of surface friction. Thermohaline circulation is the pattern by which the density of water increases as it becomes colder and saltier; thus it sinks at high latitudes and is replaced by warmer water from the tropics flowing north. This is a key mechanism that regulates Earth's climate. While different hemispheres experience different amounts of heat/light, this is not the reason for the phenomenon described in the question. Finally, ocean currents do not have the ability to dictate storm currents.

The Coriolis effect, caused by the rotation of the earth, results in clockwise currents in the northern hemisphere and counter-clockwise currents in the southern hemisphere.

The process of upwelling brings cold, nutrient-rich waters to the surface that replace warm, nutrient-depleted waters.

The littoral zone includes the intertidal zone. Outward from shore, the zones are littoral, neritic, pelagic. The benthic zone includes the ocean floor.

The pelagic zone extends neither to the sea bed nor the shore - it is open ocean. The littoral zone includes the shore and the benthic zone includes the ocean floor. The profundal zone is only present in inland bodies of water, and begins below the limit of light penetration.

Since photosynthesis depends upon solar energy, we can deduce that the zone which is least likely to contain photosynthetic organisms is the zone furthest away from the sun, and thus the deepest, lowest level of the ocean. The intertidal zone and zone of coastal upwelling are in fact closest to the coast and sun, while the pelagic zone refers to water which is further from the coast, but includes the surface (though not the sea floor). And the euphotic zone is the uppermost zone, which indeed received sunlight. Thus the least likely of these zones to contain photosynthetic organisms is the abyssal zone, the part of the ocean deeper than about 2,000 m and the deepest of this group.