Maravillas naturales bajo amenaza

by Vocafy Verificado

Inglés (Estados Unidos) B2 12 preguntas Nature & animals

Explora cómo las presiones ambientales afectan a lugares naturales famosos, desde los arrecifes de coral hasta los bosques de montaña, y descubre cómo la conservación puede ayudar.

1. 1. Elige la respuesta correcta.

   ¿Qué factor de estrés desencadena más directamente el blanqueamiento en esta situación?

   During marine heat waves, corals on the Great Barrier Reef may turn white after losing the tiny algae that live in their tissues.

   • Sediment washing into the sea
   • Unusually warm seawater
   • Increasing ocean acidity

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   • Unusually warm seawater

   Las algas proporcionan gran parte del alimento de un coral. Un coral blanqueado no está necesariamente muerto, pero el estrés térmico prolongado puede impedir su recuperación.

2. 2. Elige la respuesta correcta.

   ¿Cuál es la amenaza más directa para estos animales?

   Parts of the Amazon rainforest are cleared for cattle pasture. Animals that depend on the forest must then survive in a landscape with fewer trees.

   • Loss of suitable forest habitat
   • A shortage of open grassland
   • Expansion of continuous forest cover

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   • Loss of suitable forest habitat

   Distintas especies del bosque dependen de las copas de los árboles, los huecos en los árboles o el suelo sombreado. Un pastizal para el ganado no puede reemplazar todos estos hábitats.

3. 3. Elige la respuesta correcta.

   What environmental problem does this illustrate?

   Rats reached the Galápagos Islands on ships. On some islands, they now eat the eggs and chicks of native birds.

   • Native predators returning after a decline
   • Birds following a seasonal migration route
   • Introduced animals disrupting an island ecosystem

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   • Introduced animals disrupting an island ecosystem

   Many island species evolved without certain predators. Animals introduced by people can therefore cause damage out of proportion to their size.

4. 4. Elige la respuesta correcta.

   ¿Qué significa este desequilibrio anual?

   A glacier gains ice from accumulated snow and loses ice through melting. Many glaciers in the Alps now lose more ice each year than they gain.

   • The glacier's total volume gradually increases.
   • The glacier's total volume gradually decreases.
   • The glacier keeps the same total volume.

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   • The glacier's total volume gradually decreases.

   Un invierno con mucha nieve no garantiza que un glaciar esté en buen estado. La nieve que cae debe reemplazar el hielo perdido a lo largo de todo el año.

5. 5. Elige la respuesta correcta.

   Which change best addresses the damage caused by water diversion?

   Fresh water once moved slowly through the Everglades, following seasonal patterns. Canals and other structures have diverted much of that water away from the wetlands.

   • Restoring a more natural seasonal flow of fresh water
   • Keeping every part of the wetland deeply flooded all year
   • Draining wet areas more quickly after heavy rain

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   • Restoring a more natural seasonal flow of fresh water

   Wetland wildlife depends on the timing and depth of water, not simply on having as much water as possible.

6. 6. Elige la respuesta correcta.

   ¿Qué patrón de incendios representa la mayor amenaza para la recuperación del bosque?

   Many Yellowstone plants are adapted to occasional fires. After a severe fire, however, young trees need time to grow and produce seeds.

   • Occasional fires separated by long recovery periods
   • Small fires that leave nearby seed-producing trees alive
   • Severe fires returning before young trees can mature

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   • Severe fires returning before young trees can mature

   Estar adaptado al fuego no significa sobrevivir a todos los patrones de incendios. Los incendios intensos y repetidos pueden interrumpir la regeneración natural del bosque.

7. 7. Elige la respuesta correcta.

   How can excess nutrients threaten marine life?

   Wastewater entering Ha Long Bay can carry nutrients that encourage algae to grow. Large blooms may eventually die and decay.

   • Decaying algae release enough oxygen to support more fish.
   • The breakdown of algae can use up oxygen that fish need.
   • Extra nutrients prevent algae from growing, removing food for fish.

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   • The breakdown of algae can use up oxygen that fish need.

   Organisms that break down dead algae consume oxygen. Nutrients that support growth in small amounts can cause problems when excess amounts enter the water.

8. 8. Elige la respuesta correcta.

   Which plan best supports this seasonal movement?

   In the Serengeti, migrating wildebeest move between areas as rainfall changes where grass grows. A fence can separate two otherwise healthy habitats.

   • Protecting a route connecting seasonal feeding areas
   • Protecting only the wet-season feeding area
   • Fencing the dry-season feeding area on all sides

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   • Protecting a route connecting seasonal feeding areas

   Migrating animals need connected habitats. Protecting separate feeding areas is not enough if animals cannot travel between them.

9. 9. Elige la respuesta correcta.

   Which land-use decision would make this problem worse?

   As sea levels rise, mangroves in the Sundarbans may need to spread inland. Embankments and settlements can block that movement.

   • Leaving undeveloped space behind the mangrove forest
   • Allowing tidal water to reach suitable inland areas
   • Building more permanent barriers along the forest's inland edge

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   • Building more permanent barriers along the forest's inland edge

   This is called "coastal squeeze": rising water on one side and fixed barriers on the other leave less room for coastal habitats.

10. 10. Elige la respuesta correcta.

    ¿Qué limitación deben considerar los responsables de la gestión al planificar estas liberaciones de agua?

    Dams above the Grand Canyon trap much of the sand that once entered the Colorado River. Managers sometimes release extra water to help rebuild downstream sandbars.

    • Releasing extra water automatically restores the original sand supply.
    • The flow needs enough available sand to deposit along the river.
    • The strongest flow creates the largest lasting sandbars, regardless of sand supply.

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    • The flow needs enough available sand to deposit along the river.

    El agua puede mover la arena, pero no puede reemplazar un aporte faltante. Las corrientes fuertes también pueden arrastrar la arena existente más lejos, río abajo.

11. 11. Elige la respuesta correcta.

    Which action targets the immediate disease pathway?

    In the mountain forests of Hawaii Volcanoes National Park, cool conditions have helped some native birds avoid disease-carrying mosquitoes. Warming allows these mosquitoes to survive farther uphill.

    • Reducing mosquito populations near the remaining bird habitats
    • Restoring vegetation without addressing disease carriers
    • Reducing visitor noise while leaving mosquito populations unchanged

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    • Reducing mosquito populations near the remaining bird habitats

    Climate change can harm wildlife indirectly by changing where disease carriers can live. Cooler mountain habitats may no longer provide the same protection.

12. 12. Elige la respuesta correcta.

    Which approach addresses both local damage and ocean acidification?

    Belize's Great Blue Hole lies within protected marine waters. Local rules can limit direct damage, but carbon dioxide from worldwide emissions still enters seawater and makes it more acidic.

    • Relying on stronger local restrictions without addressing global emissions
    • Focusing on global emissions instead of maintaining local protection
    • Maintaining local protections while reducing global carbon emissions

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    • Maintaining local protections while reducing global carbon emissions

    Protected boundaries cannot keep out changes in ocean chemistry. Acidification makes building and maintaining shells or skeletons harder for many marine organisms.