As Sudd

As Sudd, swampy lowland, southern Sudan, in eastern central Africa. The region is about 320 km (about 200 mi) long and about 360 km (about 220 mi) wide. It is fed by major tributaries of the north-flowing White Nile, including the Baḩr al ‘Arab. Just north of Bor, the White Nile overflows onto a broad clay plain. Because the gradient of the land is so low, the rivers’ waters spread to form many swamps and lagoons. Papyrus and floating water plants, known in Arabic as sudd, grow densely in the region. The river is no longer navigable in As Sudd, as half of its water evaporates in the slow-moving waterways. The Dinka and Nuer peoples live in the grassy plains between the watercourses. Since about the 10th century, these pastoral peoples have raised herds of cattle, sheep, and goats for their livelihoods.