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Main Wind direction
Tree Sang Stocking Belt
Tree and Shrub
Sand Stocking Belt
Closing Belt
Sand Driving Wind from Gobi
Network in
farmland
50-100m
300-500m
10-20m
Fig. 3.6
Comprehensive system for sand control near Aydingkol Lake, Turpan county Xinjiang
Haloxylon ammondendron and Calligonum spp . on mobile sand dunes within 100 m
out of sand-stocking forest belt. Combined with the placement of sand barriers,
sand-closing belt for rehabilitating natural vegetation whose width is 200-500 m is
placed on the periphery of sand-fixing belt (Fig. 3.4 )
Example 3. The area surrounding Aydingkol Lake in Turpan County
Turfan is an arid area in Xinjiang. Irrigation water is often available in late
summer and autumn after the crops have matured. This water can be used to
irrigate the sandy land and afforest it outside of sand-closing belt, the forest belt
that is disposed in multi-belt and where wide rows alternate with narrow rows for
stocking blown sand is planted with trees ( Populus alba var. pyramidalis, Elaeagnus
angustifolia, Ulmus pumila etc.) and shrubs ( Tamarix spp. ) on it. Shelter forest
systems of oases in sandy desert include closing belt for grasses (shrubs) established
along front line of mobile dunes, land-break and sand-stock forest belt along the
edge of oases and forest network in farmland in oases (Figs. 3.6 and 3.7 ).
5.3
Planting Forest on Lowlands
This measure is common in Mu Us sandy land in inner Mongolia, this is called
“blocking shifting sand dune in front and dragging it from behind”. The Wushen-
zhao plain in the north of Mu Us sandy land is taken as the example here.
The actual method is to take the trees as major species to afforest in lowlands
among shifting sand dunes so as to break up and surround mobile sand dunes, plant
sand-fixing plants on lower (1/3) part of the windward slope of the dune to form
“dragging dune from behind”, thus the middle and upper parts of the wind ward side
is eroded by wind constantly, the height of dune declines constantly even a concave
is formed by wind erosion in former upper part of dune, at this time, sand-fixing
plants are planted on the concave (Fig. 3.8 ). This continues until the whole sand
dune become even. In general, this process takes about 5 years, thus the coverage of
controlled sand land could increase to over 50 %, as shifting sand is stabilized.
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