- The extremely arid desert climate is the best preserver of murals.
- Egina Oasis in the low reaches of Heihe River is extremely arid, Heihe River is the only source of water.
- But because of its extreme arid torrid climate, hypsography low-lying, gale and frequent wind and other unique physica1 geography characteristics, its nature ecological environment are extremely bad and frail.
- In Tarim river basin, the climate is extremely arid and the ecologic environment is fragile.
- Arid and extremely arid land are deserts, and semiarid grasslands generally are referred to as steppes.
- As an extremely arid desert oasis, Heihe River is the only source of water in Ejin Oasis.