Abstract
The patterns of phytogenic field formation under the environment-forming influence of Haloxylon aphyllum in Karnabchul desert are considered. The dynamics of soil moisture and the thermal regime of air and light in the phytogenic field is shown. The nature of the distribution and accumulation of the phytomass of grass plants ( Poa bulbosa and Carex pachystylis ) within and outside the phytogenic field of black saxaul are described.