Problem: I read this background article the other day: At the mid-oceanic ridges, two tectonic plates diverge from one another as new oceanic crust is formed by the cooling and solidifying of hot molten rock. Because the crust is very thin at these ridges due to the pull of the tectonic plates, the release of pressure leads to adiabatic expansion (without transfer of heat or matter) and the partial melting of the mantle, causing volcanism and creating new oceanic crust. Most divergent plate boundaries are at the bottom of the oceans; therefore, most volcanic activity on the Earth is submarine, forming new seafloor. Black smokers (also known as deep sea vents) are evidence of this kind of volcanic activity. Where the mid-oceanic ridge is above sea-level, volcanic islands are formed; for example, Iceland.  I am facing a new situation today: Two oceans have divergent plate boundaries at the bottom of their floor. The Arctic ocean has a single dormant divergent plate, while the Pacific ocean has seven diverging tectonic plates under its waters.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which ocean experiences more volcanism?

A: Pacific


Problem: I read this background article the other day: Biodiversity loss is the extinction of species (plant or animal) worldwide, and also the local reduction or loss of species in a certain habitat.  The latter phenomenon can be temporary or permanent, depending on whether the environmental degradation that leads to the loss is reversible through ecological restoration / ecological resilience or effectively permanent (e.g. through land loss). Global extinction has so far been proven to be irreversible.  Even though permanent global species loss is a more dramatic phenomenon than regional changes in species composition, even minor changes from a healthy stable state can have dramatic influence on the food web and the food chain insofar as reductions in only one species can adversely affect the entire chain (coextinction), leading to an overall reduction in biodiversity, possible alternative stable states of an ecosystem notwithstanding. Ecological effects of biodiversity are usually counteracted by its loss. Reduced biodiversity in particular leads to reduced ecosystem services and eventually poses an immediate danger for food security, also for humankind.[1]  I am facing a new situation today: Rob is an environmental scientist. He is studying the effect of insect species on environment. For his study he chose four locations, location A, location B, location C and the entire globe, which he denoted as location D. He noticed location A's loss of biodiversity is temporary , but location B's loss is permanent. Location C's loss of biodiversity yet to be determined.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Would ecological restoration be helpful or not helpful for location B?

A: not helpful


Problem: I read this background article the other day: The quantity of small plastic fragments floating in the north-east Pacific Ocean increased a hundredfold between 1972 and 2012.Marine pollution is a generic term for the harmful entry into the ocean of chemicals or particles. The main culprits are those using the rivers for disposing of their waste. The rivers then empty into the ocean, often also bringing chemicals used as fertilizers in agriculture. The excess of oxygen-depleting chemicals in the water leads to hypoxia and the creation of a dead zone.Marine debris, also known as marine litter, is human-created waste that has ended up floating in a lake, sea, ocean, or waterway. Oceanic debris tends to accumulate at the center of gyres and coastlines, frequently washing aground where it is known as beach litter.In addition, the Pacific Ocean has served as the crash site of satellites, including Mars 96, Fobos-Grunt, and Upper Atmosphere Research Satellite.  I am facing a new situation today: Tim and Joe were two friends living near two different oceans. Tim lived on the Pacific coast while Joe lived on the Atlantic coast.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which friend sees more marine pollution?

A: Tim


Problem: I read this background article the other day: Huge amounts of chemicals, such as fertilizers and pesticides, are applied to farm fields (see Figure below ). Some of the chemicals are picked up by rainwater. Runoff then carries the chemicals to nearby rivers or lakes. Dissolved fertilizer causes too much growth of water plants and algae. This can lead to dead zones where nothing can live in lakes and at the mouths of rivers. Some of the chemicals can infiltrate into groundwater. The contaminated water comes up in water wells. If people drink the polluted water, they may get sick.  I am facing a new situation today: Two neighboring towns used different approaches to agriculture. Big town used pesticides and fertilizers, while Small town applied permaculture principles and organic farming methods.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which town had more growth of algae because of fertilizer?

A:
Big