The Hawaiian Islands contain active volcanoes and are known for nutrient-rich soils and lush vegetation. What is the most powerful explanation for this?
Volcanic rocks contain minerals susceptible to hydrolysis.
Minerals in the volcanic rocks produce clay minerals as weathering by-products.
Volcanic rocks contain minerals rich in iron, so they are susceptible to oxidation.
all of the above
There is abundant rainfall.
hint; Soil formation in the Hawaiian Islands is the result of extensive weathering of volcanic basalts. Which of the following explains not only why the weathering occurs, but why the resultant soil is particularly good for plant growth?
Volcanic rocks contain minerals susceptible to hydrolysis.
Minerals in the volcanic rocks produce clay minerals as weathering by-products.
Volcanic rocks contain minerals rich in iron, so they are susceptible to oxidation.
all of the above
There is abundant rainfall.
hint; Soil formation in the Hawaiian Islands is the result of extensive weathering of volcanic basalts. Which of the following explains not only why the weathering occurs, but why the resultant soil is particularly good for plant growth?
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all of the above
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To have both nutrient-rich soils and lush vegetation you need both the nutrients and the rainfall.
The most important nutrients for fertile soil are nitrogen, phosphorus and potassium, but there are many other minerals that can help plants grow. Volcanic rock breaks down to release many of these minerals. In particular, the mineral feldspar is quite easy to break down and form clay minerals that can easily release the elements needed for plant nutrition.
Lush vegetation cannot grow without sufficient water. Other volcanoes with similar volcanic soils will not have much vegetation on the areas with little rainfall such as in the Canary islands off northwest Africa.
The most important nutrients for fertile soil are nitrogen, phosphorus and potassium, but there are many other minerals that can help plants grow. Volcanic rock breaks down to release many of these minerals. In particular, the mineral feldspar is quite easy to break down and form clay minerals that can easily release the elements needed for plant nutrition.
Lush vegetation cannot grow without sufficient water. Other volcanoes with similar volcanic soils will not have much vegetation on the areas with little rainfall such as in the Canary islands off northwest Africa.