Within Southwest Asia, however, the distribution of oil is uneven. Saudi Arabia is the largest country in this region, and it also has the most oil. In fact, approximately one quarter of the world's proven oil reserves lie under its desert sand. Kuwait, in contrast, is a tiny country. Saudi Arabia could contain 125 Kuwaits and still have space left over, but little Kuwait holds almost a tenth of the world's known oil reserves. Other countries in Southwest Asia, such as Syria and Yemen, have less oil, but they still have more oil than most other countries in the world. In 2009, OPEC had 12 member countries. Six members were Southwest Asian countries, but the organization includes six oil producers from outside the region: Algeria, Angola, Ecuador, Libya, Nigeria, and Venezuela. Meanwhile, not all of the Southwest Asian oil producers belong to OPEC. Bahrain, Yemen, Oman, and Syria have not joined the organization. OPEC wants oil prices to be steady—not too high and not too low. If too much oil is offered for sale, there will be less competition among buyers to purchase the oil they need. As a result, prices will drop too low. On the other hand, if too little oil is offered for sale, there will be more competition between buyers, causing prices to rise too high. In order to keep prices steady, OPEC members have agreed to regulate how much oil they will sell.
However, two realities limit OPEC's ability to control oil prices. First, OPEC cannot control all of the world's oil sales because its members export less than half of the world's crude oil. The rest of the crude oil comes from non-OPEC countries such as Russia and Mexico. Second, even OPEC members don't always act as a united group. For example, sometimes some members refuse to follow OPEC decisions on how much oil to sell.
happens in a different way. When farmers irrigate their crops, they bring water from lakes and rivers to their fields. Often this fresh water contains a little salt. When the water evaporates, it leaves the salt behind on the surface of the soil. There might not be enough salt on the surface to damage plants, at least at first. However, if people don't wash the salt away, the soil becomes saltier as the years pass. Very few plants can grow in salty soil. The water and land in the region surrounding the Aral Sea have both been degraded by salinization. The Aral Sea used to be Earth's fourth-largest freshwater lake. Now it's about 10 percent of its original size and split into two parts. The larger part, in the south, is as salty as any ocean. The smaller part, in the north, is also still too salty to drink, but recent projects are starting to bring fresh water back into this part of the sea.