Which agricultural practices has the most significant long-term environmental impact in tropical regions?

The correct answer is option "Burning extensive areas of forested land to create pasture, which decreases biodiversity".

Explanation:

The missing options of this question are:

A) Clearing small patches of land to pasture dairy cows, which decreases water pollution from runoff.

B) Building terraces on sloping land to grow rice, which destabilizes hillsides.

C) Burning extensive areas of forested land to create pasture, which decreases biodiversity.

D) Moving livestock to higher pasture areas in the spring, which leads to soil degradation.

The correct answer is option C) "Burning extensive areas of forested land to create pasture, which decreases biodiversity".

Tropical regions are rich in forested landscapes, where multiple species of animals and plants live. The agricultural practice that most significant long-term environmental impact is to burn these areas to create pasture. It is estimated that burning forested lands cannot be recovered in least than 28 years, while some areas have permanent damages.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.