Suitable oasis scale in a typical continental river basin in an arid region of China: A case study of the Manas River Basin

Abstract: An oasis is defined here as an efficient eco-geographical landscape that allows flourishing vegetation or human settlement due to a stable water supply in an arid region. The water resource is the major limiting factor impacting the oasis scale in arid regions. For discussion of the suitable scale of an oasis supported by a specific quantity of water resource, the Manas River Basin, a typical continental river basin in the arid region of China, was taken as the study object. Based on the remote sensing images and socio-economic data, the stability and suitable scale of oasis in 1976, 1987, 1998, 2010, and 2020 were analyzed using an oasis water-heat balance model. The results indicated that (1) the respective stability index (H 0) of 1976, 1987, 1998, and 2010 was 0.10, 0.15, 0.40, and 0.38, respectively, changing from an unstable level into a metastable level. (2) 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. (3) If the artificial oasis scale remained unchanged from 2010, the suitable scale of the natural oasis in the Manas River Basin in 2020 would be 1695.8–2543.8 km2, and the suitable scale of the total oases would be 8398–9246 km2. With a reasonable proportion between natural and artificial oases, the suitable scales of each would be 3400.3–5100.5 km2 and 2266.9–3400.4 km2. This paper 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. [Copyright &y& Elsevier]