Answer:
The answer is C)
Explanation:
The predators were unable to keep the population of the mussels down. The mussels took more area of the rock. Other species that needed space did not return to the tidal pool. Otters can also be keystone species as they eat urchins. By doing so, they prevent the sea urchins form eating all the kelp plants and removing the entire habitat for many other species. The Keystone Species theory shows that this impact of few predators, that made up a minor amount of the total species, could have such a high impact on the ecosystem.
We can control resource depletion by rationing them and making thing that don't need or use so much resources.
Lava flows are the least hazardous of all processes in volcanic eruptions. How far a lava flow travels depends on the flows temperature, silica content, extrusion rate, and slope of the land. A cold lava flow will not travel far and neither will one that has a high silica content. Such a flow would have a high viscosity<span> (a high resistance to flow). A basalt flow like those in Hawai'i have low silica contents and low viscosities so they can flow long distances. Such a flow can move as far away as 4 km from its source and have a thickness of 10 m (Bryant, 1991). These flows can move at rates of several kilometers per hour (Scott, 1989). </span><span>More silica-rich flows can move as far away as 1.3 km from their sources and have thicknesses of 100 m (Bryant, 1991). These flows can move at rates of a few to hundreds of meters per hour (Scott, 1989). If a lava flow is channelized or travels underground in a lava tube then the distance it travels is greatly extended.</span>
