Over the past decade, our understanding of plant adaptation to environmental
stress, including both constitutive and inducible determinants, has grown con-
siderably. This book focuses on stress caused by the inanimate components of
the environment associated with climatic, edaphic and physiographic factors
that substantially limit plant growth and survival. Categorically these are abiotic
stresses, which include drought, salinity, non-optimal temperatures and poor
Maxim, an extreme xeric semi-shrub of Tamaricaceae, is a
constructive and dominant species of desert shrub vegetation (Liu et al. 1982; Wang et al.,
2011; Bai et al., 2008). It is distributed widely on a large area of sand wasteland (Fig. 1a) and
saline land (Fig. 1b) in arid and semiarid regions of central Asia from the western Erdos,
Alaskans, Hexi Corridor, Qaidam Basin to Tarim Basin and Jungar Basin (from the east to
the west) and forms the vast and distinctive landscape of the salt desert (Liu and Liu, 1996).
The distribution of R.
The great depth and high fertility of the soils of arid and semiarid regions have made possible the profitable production of agricultural plants under a rainfall very much lower than that of humid regions. To make the principles of this system fully understood, it is necessary to review briefly our knowledge of the root systems of plants growing under arid conditions.
The great nations of antiquity lived and prospered in arid and semiarid countries. In the more or less rainless regions of China, Mesopotamia, Palestine, Egypt, Mexico, and Peru, the greatest cities and the mightiest peoples flourished in ancient days. Of the great civilizations of history only that of Europe has rooted in a humid climate. As Hilgard has suggested, history teaches that a high civilization goes hand in hand with a soil that thirsts for water. To-day, current events point to the arid and semiarid regions as the chief dependence of our modern civilization.