Tigris–Euphrates river system border. Since the 1960s and in the 1970s, when Turkey began the GAP project in earnest, water disputes have regularly occurred in addition to the associated dam's effects on the environment. In addition, Syrian and Iranian dam construction has also contributed to political tension within the basin, particularly during drought. The general climate of the region is subtropical, hot and arid. At the northern end of the Persian Gulf is the vast floodplain of the Euphrates, Tigris, and Karun Rivers, featuring huge permanent lakes, marshes, and forest. The aquatic vegetation includes reeds, rushes, and papyrus, which support numerous species. Areas
Euphrates unrecorded substrate language. Tamaz V. Gamkrelidze and Vyacheslav Ivanov suggest the Proto-Sumerian *burudu "copper" (Sumerian "urudu") as an origin, with an explanation that Euphrates was the river by which the copper ore was transported in rafts, since Mesopotamia was the center of copper metallurgy during the period. The earliest references to the Euphrates come from cuneiform texts found in Shuruppak and pre-Sargonic Nippur in southern Iraq and date to the mid-3rd millennium BCE. In these texts, written in Sumerian, the Euphrates is called "Buranuna" (logographic: UD.KIB.NUN). The name could also be written KIB.NUN.(NA) or KIB.NUN, with the prefix "" indicating