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affected by soil salinization. Application of such approaches solves the animal feed
gaps in the lands degraded both by overgrazing and salinity, and promotes increased
income for farmers. Agro-silvi-pastoral trials used for rehabilitation of saline soils
represent a model for preservation and/or restoration of ecosystem function/services
for agropastoral communities as part of their adaptation measures to climate change.
The coexistence of C
3
and C
4
species is facilitated because C
3
species can colonize
nutrient rich microsites, while C
4
species can occupy nutrient poor microsites.
Comparing different species within a small scale habitat along a salinity gradient
we found that short-lived annuals or herbaceous species had significantly lower
values of forage biomass than perennial species. The selection for trees with low
13
C and, therefore, high transpiration efficiency, has the potential to increase total
tree biomass growth in water-limited arid saline environments. Results obtained in
this study showed that the successful performance of dryland afforestation technique
is based on partial overlapping of natural niches of C
3
/C
4
species. Therefore the
optimal rehabilitation technique of saline prone rangelands consists from 12 % of
tree cover, 20 % wild xerohalophytes, 38 % of biennual and 30 % annual forage
crops, which in mixed planting significantly increase the productivity of rangelands.
They prevent the accumulation of salts in the root zone. Results of this research
indicate the suitable co-existence of C
3
and C
4
species is facilitated because C
3
species can colonize nutrient rich microsites, while C
4
species can occupy nutrient
poor microsites.
There are a number of both C
3
and C
4
plants suitable for reclamation of
salt/affected and waterlogged drylands that have proven very useful in demonstra-
tion trials. They provide potential to re-use areas that have been abandoned by
agro-pastoralists and which are not used as part of the arid fodder production system.
Incorporation of fodder halophytes into the agro-silvo pastoral system or domes-
tication of wild halophytes species represents low cost strategies for rehabilitation
of desert degraded rangelands and abandoned farmer lands affected both by soil
and water salinity. Late summer and early autumn time should be considered
as the optimal period for transplanting of all the above mentioned non con-
ventional halophyte species. Introduction of strip-alley livestock-farming system
increased the productivity of rangelands by 2.0-2.5 times and slowed further
degradation of rangelands. The proposed system (developed by the authors) of
creation of agro-phytocenosis by mixture of natural halophytes with salt tolerant
crops, fodder legumes and grass allow getting forage for animals almost all of
the year. Salt tolerant crops cultivated into an agro-silvo-pastoral model benefits
from the improvement of soils and microclimatic conditions provided by the shrubs.
Considerable reductions were observed in wind speed, potential evapotranspiration,
temperature and in the intensity of sand storms. First screening of wild halophytes
for their gradual domestication should be done based on the following criteria: ash
composition of forages; nutritional values and needs of farmers.
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