The correct answer is - A. replacing natural vegetation with cultivated crops.
The natural vegetation is perfectly adapted to a certain environment, and it is also able to keep the soil tight with its roots, so the erosion is minimal.
When the natural vegetation is replaced by cultivated crops, than a problem occurs in the erosion of the soil. That is because the cultivated crops, in general, do not have root systems that are as strong and widespread as the natural vegetation, thus the soil becomes loosened up, so it is much easier to be eroded.
Pangaea would be you answer.
Answer:
When discussing drought, one must have an understanding of aridity and the difference between the two. Aridity is defined, in meteorology and climatology, as "the degree to which a climate lacks effective, life-promoting moisture" (Glossary of Meteorology, American Meteorological Society). Drought is "a period of abnormally dry weather sufficiently long enough to cause a serious hydrological imbalance". Aridity is measured by comparing long-term average water supply (precipitation) to long-term average water demand (evapotranspiration). If demand is greater than supply, on average, then the climate is arid. Drought refers to the moisture balance that happens on a month-to-month (or more frequent) basis. If the water supply is less than water demand for a given month, then that month is abnormally dry; if there is a serious hydrological impact, then a drought is occurring that month. Aridity is permanent, while drought is temporary.
Answer:
Explanation:
Os impactos ambientais negativos do turismo são substanciais. Eles incluem o esgotamento dos recursos naturais locais, bem como problemas de poluição e resíduos. O turismo muitas vezes pressiona os recursos naturais por meio do consumo excessivo, muitas vezes em lugares onde os recursos já são escassos.
O turismo coloca enorme pressão no uso da terra local e pode levar à erosão do solo, aumento da poluição, perda de habitat natural e mais pressão sobre as espécies ameaçadas de extinção. Esses efeitos podem destruir gradualmente os recursos ambientais dos quais o próprio turismo depende.
