The Democratic Republic of the Congo (DRC) (About this soundpronunciation (help·info) French: République démocratique du Congo (RDC)), also known as Congo-Kinshasa, DR Congo (French: RD Congo), the DROC,[6] or simply either Congo or the Congo, and historically Zaire, is a country in Central Africa. It is, by area, the largest country in sub-Saharan Africa, the second-largest in all of Africa (after Algeria), and the 11th-largest in the world. With a population of over 101 million, the Democratic Republic of the Congo is the most-populous officially Francophone country in the world, as well as the 2nd-most populous country in Africa (after Nigeria), and the 13th-most populous country in the world. Since 2015, the Eastern DR Congo has been the scene of an ongoing military conflict in Kivu.
The first one. The use of irrigation.
The geographic term “Asia” was originally used by ancient Greeks to describe the civilizations east of their empire. Ancient Asian peoples, however, saw themselves as a varied and diverse mix of cultures—not a collective group. Today, the term “Asia” is used as a cultural concept, while subregion classifications describe the distinct geopolitical identities of the continent. These classifications are Western Asia, Central Asia, Southern Asia, Eastern Asia, Southeastern Asia, and Northern Asia.
Answer:
This is the best explanation for why there is such a small amount of phosphorus that moves into aquatic systems:
1. Phosphorus is highly stable in the atmosphere and remains there for long periods of time.
Explanation:
The phosphorus first cycle is the process by which the phosphate ion passes in very small amounts through the lithosphere from volcanic aeorosols, then to the hydrosphere, where it stays from 20,000 to 100,000 years in the ocean, and finally to biospherere, where rain and erosion helps washing the phosphorus from the rocks into the soil. So, raining is the beginning of the phosphorus´s second cycle, so it is also, the slowest one of the matter cycles that is why the natural total background phosphate levels in several bodies of freshwater range from 0.005 to 0.05 mg/L. Phosphorus remains mostly on land and in rock and soil minerals.
Although abundant on our planet´s sedimentary rock crust and in human body, phosphorus to commercialize is only found in minerals therefore, phosphates mining activity and calcium heating is the only way to get it in its pure elemental form. It is an essential nutrient for plants and animals and a big percentage of the mined phosphorus is used to make fertilizers.
