Suitable Oasis Scale in a Typical Continental River Basin in an Arid Region of China

Oasis is the unique synthesis that combines nature with artificiality and is essential in arid and semi-arid regions. To build a stable, efficient, and sustainable oasis in arid and semi-arid regions, it is necessary to advance the studies on the suitable oasis scale based on the capacity of water resources and certain economic and technical conditions. However, previous studies have not separated natural oasis from artificial oasis when calculating suitable scale of oasis, and the suitable scale of oasis under different conditions of water resources and economic development in different periods was also not considered.

The Manas River Basin has a typical mountain-oasis-desert ecosystem in the arid and semi-arid region of China. In recent years, the artificial oasis area increased rapidly, while the natural oasis area was on a rapid decrease owing to water resources shortage. Therefore, to realize the coordinated development of ecosystem and socio-economy in the Manas River Basin, based on six periods of remote sensing images and water-heat balance model, prof. XU Hailiang et al. analyzed the stability and suitable scale of the oasis. In the analysis processes, the utilization efficiency of water resource was taken as the principal line under the background of global climate change. 

The results indicated that the respective stability index of 1976, 1987, 1998, and 2010 was 0.10, 0.15, 0.40, and 0.38, changing from unstable level into metastable  level. Under the guarantee of natural oasis ecosystem stability, the suitable scales of natural oasis in 1976, 1987, 1998, and 2010 were 697.2–1045.7 km², 942.2–1413.3 km², 2042.0–3063.0 km², and 1428.2–2142.3 km², respectively. The suitable scales of the total oases were 3681.3–4030.3 km², 5259.1–5730.2 km², 7654.5–8675.5 km², and 8130.3–8844.4 km², respectively.

As the artificial oasis scale would remain unchanged in 2010, the suitable scale of natural oasis in the Manas River Basin would be 1695.8–2543.8 km², and the suitable scale of the total oases would be 8398–9246 km² in 2020. Under the reasonable proportion of natural and artificial oasis, the suitable scales of the two would be 3400.3–5100.5 km² and 2266.9–3400.4km².

This study not only provides data for reasonable oasis planning of the Manas River Basin, but also provides a new direction for studies on the suitable scale of oases in arid regions. The result was published in Quaternary International on 2013, 286: 116–125.