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halophytes and other salt-tolerant crops is the
production and conservation of germplasm of important
seeds. The demand for seeds of salt-tolerant species has
increased and a number of farmers have become
interested to apply biosaline agriculture techniques as a
feasible option for marginal lands. An innovative
selection programs and development of suitable
modern agro-technologies were suggested to multiply
seeds of valuable salt tolerant
species and establish
them within natural plant communities, where they are
suitable in different ecosystems. However, the outline
of the general strategies for salt affected and degraded
rangelands regeneration and management in new
human changing desert/semi-desert environments and
socio-economic systems should still be developed and
modeled.
Our findings from the screening of 16
multipurpose tree
species offer a spectrum of
options for afforesting degraded land. In order to
implement afforestation of marginal patches of
irrigated land in Kyzylkesek site (Kanimekh district,
Navoi region, Uzbekistan ), Amudarya River Delta
(Khorezm region in Uzbekistan and Dashauz province
from Turkmenistan),
the ideal multipurpose tree
species should combine a number of features such as:
high survival rate, quick growth, halophytic and
xerophytic characteristics, and high utility value of
firewood and/or foliage. Salt tolerant trees and/or
shrubs species, e.g.,
Populus euphratica, P. pruinosus,
P. nigra var. Pyramidalis, Elaeagnus angustifolia,
Morus alba, M. nigra, Robinia pseudoacacia, Tamarix
hispida, T. androsowii, Salix babylonica, S. songarica,
Haloxylon aphyllum, Cynadon oblonga, Armeniaca
vulgare,
Malus domestica
, Acacia ampliceps
and
various perennials shrubs, such as species of genus
Atriplex, Hippophae ramnoides Ribes niger & Rosa
canina
(exceptional under arid continental with
subtropical elements climate
)
established on good deep
soils have good potential as part of the silvi-
agropastoral production system. Fodder shrubs were
associated
with the cereal farming system, including
native rangelands halophytes alone, or mixed with
various traditional salt tolerant fodder crops. As part of
the desert land re-vegetation and/or rangeland
improvement saltbushes
Atriplex canescens, A. nitens,
A. undulata, A. nummularia
and
A. amnicola
were
recently introduced at the saline
sandy desert zones of
low-lying salt affected areas of Central Asian River
deltas. Our preliminarily results showed that the
establishment trees/shrubs plantations requires limited
irrigation during the initial stage of growth before sole
reliance on available groundwater resources can
become possible. Since the availability of irrigation
water
on marginal lands is limited, there is a need for
assessment of the ground water budget, root –zone salt
accumulation control and distribution, as well as
studying the adoption of water-saving irrigation
techniques, which are being applied on tree plantations
in other arid regions of the world (Andreu et al., 1997;
Levy et al., 1999). It was found that the high
productivity of
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