沙漠研究 24-1, 47-50 (2014)
Ἃ₍◊✲ 24-1, 47 -50 (2014)
Journal of Arid Land Studies
Journal of Arid Land Studies－ DT11 Refereed Paper －㸫DT11 Refereed Paper㸫

Habitat Change and Plants Invasion in Great Engineering Protective System in
Gurbantunggut Desert, China (2000-2009)
Xueqin WANG*1), Xinwen XU 1), LichaoLIU 2) and ChunwuSONG 1)
Abstract: The great lined engineering in the hinterland of Gurbantunggut Desert, such as construction of highways and water
channels etc. always make strong disturbance to the ground surface. In order to protect ecosystems and control blown-sand disease,the disturbed sand surface on both sides of the engineering project was stabilized by 1 m × 1 m straw checkerboard barriers. Thenshrubs were planted at 2 m × 2 m spacing inside the barriers. Based field measurements of plant species and density and analysis ofsoil characteristics in the protective system, as well as on the natural dune surface, habitat change and plants invasion from 2000 to2009 were observed. The disturbed sand surface can be stabilized by straw checker-board barrier. Organic matter and fine sandbegan to accumulate on the surface with time. Water content of soil in the prevention system was greater during the first two-years
compared to water content on the natural ground (control), but it exhibited a gradual decreasing trend with time. A total of 48 plant
species were identified in the natural dune surface, including 1 dwarf tree, 4 shrubs, 13 perennial and annual herbages and 30
ephemeral plants. Herbages, especially ephemerals, can enter the protective system naturally. 8 species and 1.4 plants/m2 weremeasured in the prevention system in 2001, while they reached 33 species and 14 plants/m2 in 2009. Out of the total number of allinvasion plants, ephemeral plants accounted for over 85% while the dwarf arbor and shrubs were scarcely observed. With decline ofsoil water and encroachment of herbage plants and biological crusts, the development of artificial vegetation needs additional
investigation to refine techniques in the future.
Key Words: Ephemeral plants, Plant invasion, Protective system, Soil property
observed. The aim of this study was to provide a theoreticalbasis for rational establishment of a protective forest system inthe desert.

1. Introduction
Gurbantunggut Desert, located in the Junggar Basin in thenorth Xinjiang Autonomous Region, is the largest fixed andsemi-fixed desert in China. Under natural conditions thedesert plants grow well and biotic crusts develop extensively,
and therefore the sand surface is stable (Wang et al., 2005).
In recent years extensive construction has created intensive
destruction to the ground surface. In order to protect thedesert ecosystem and control blown-sand disease, theprevention system made up of straw checker-board barriers
and artificial vegetation was set up in areas degraded by therecent construction following the destruction of ground surface.
However the comprehensive protective system was faced withmany problems to be answered. Especially a detailed study
on habitat change and sustainability of artificial vegetation isrequired. In this paper, the field measurements of plant
species and their densities were made on the natural dune
surface and in the protective system from 2001 to 2009. Soilproperties, such as soil water, soil grain size and organic matteretc., were analyzed as well. Habitat change and plantsinvasion in the protective system from 2001 to 2009 were
* Corresponding Author: xqwang@ms.xjb.ac.cn

2. Study Area and Methods
Gurbantunggut Desert is located between 44°11’-46°20’N
and 84°31’-90°00’E, with an area of 4.88×104 km2. It ismainly covered by fixed and semi-fixed longitudinal dunes,
ranging from a hundred meters to more than 10 km long, 10-50
m high, and north-south oriented. The interdunes and the
middle to lower parts of the dune are stabilized but their crests
are mobile. The annual average temperature is 7.2°C and the10°C accumulative temperature is about 3500°C. Mean
annual precipitation is 129 mm, of which 50% is received from
April to July. Annual evaporation exceeds 2000 mm.
Gurbantunggut Desert has a 20 cm thick snow cover during
winter and it melts in early spring. Moisture affected by snow
melting and spring rainfall is limited to a depth of 30-50 cm
and lasted about 60 days, and that is the key factor responsible
for the widespread distribution of ephemeral plants (Zhang andChen, 2002). Haloxylon persicum is the dominant species,
mainly appearing at the middle to upper parts of dunes.
㸦Received, September 5th, 2013; Accepted, January 9th, 2014㸧

No. 818 Beijing South Road, Urumqi, Xinjiang, 830011, China1) Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences
2) Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences

48Interdune and middle to lower slopes are covered by Ephedra
distachya communities and beneath them are ephemeral plants
and biological crusts. Soil is dominated by blown sand withfine grain size and loose structure. Controlled by westerly aircurrent and Mongolian high pressure, the main wind directions
are NW and NE. Spring and summer are the windy seasons.
The study site is located in the southern part ofGurbantunggut Desert (44°32’30”N㸪88°6’42”E). A greatwater channel with WNW-SSE orientation was constructed in2000 and formed a disturbed belt about 240 m wide. The
disturbed sand surface on both sides of the channel wasstabilized by 1 m × 1 m straw checkerboard barriers in 2001.
Then two shrub species, Haloxylon persicum and Calligonum
leucocladum, were planted at 2 m × 2 m spacing inside thebarriers. A typical section perpendicular to the engineering
trend was selected as the survey sample belt, which was 240 mlong. Steel pins were inserted along the section in order toobserve the sand surface change of protective system, while aparallel bare sand section was selected for the survey as well.
During the 2011 windy season the heights of steel pins along
the two sections were measured respectively after two
sand-moving wind events. Negative values indicated winderosion and positive values indicated wind deposition. The
total surface activity value was calculated by Giles method(Giles et al., 1995). In 2001, 2002, 2006 and 2009 the plant
species and density inside each straw grid in the transect weresurveyed. In the meantime some quadrants were arranged on thenatural dune surface and the plants survey was synchronously
made. The soil water of 100 cm layer in the protection system
and natural dunes were observed as well. Every two years soil
samples of 0-5 cm and 5-10 cm layers were collected to measureorganic matter content and grain size component.

3. Results and Discussion
3.1. Habitat change3.1.1. Sand surface stability
After the first sand-moving windy event in 2001 thechange of bare sand surface ranged from -60-87 mm, whilemeasurements of the change in bare sand surface within theprotective system was -19-20 mm. After the second windy
event the control area (bare) measurements indicated -220-311
mm change in bare sand surface while the protective systemmeasured -17-20 mm. During the period from Apr. to May in2001 the total surface activity value at bare sand ground was
2.4 mm day-1, while inside the protective system it was 0.48
mm day-1. We observed that wind erosion and deposition
occurred alternately in bare sand sections. This is because thegrains on free sand surface are picked up and transported bywind and dropped quickly due to gravity and, therefore, theFig. 1. Various changes of organic matter in 0-5 cm and 5-10 cm soillayers.

initial flat bed surface changes into an undulate surface with acertain distance (Song and Wang, 2001). Slight erosion
widely occurred within the protective system because sandgrains in the center of each straw grid are transported to thestraw stems and therefore form into a stable concave surface.
3.1.2. Soil grain size and organic matterIn 2001 the soil grain size component in the 0-5 cm and5-10 cm layers showed no obvious differentiation in theprotective system. The percentage of medium, fine,extra-fine and silt materials of the 0-5 cm layer accounted for17.16%, 56.12%, 24.90% and 1.82% respectively in 2002, andin 2009 they reached 6.98%, 59.13%, 26.18% and 7.72%,respectively. By 2009 biological crusts extensively occurred
inside the protective system, which may be a result of theaccumulation of silt materials on the soil surface (Wu et al.,2003). For the natural dune sand surface, organic matter
content in the 0-5 cm soil layer had a significant change at
different positions (Fig. 1(a)). The interdune had an organic
matter content of 0.236% or more, while in the crests of thedune it was only about 0.045%. In 2001, the organic matter
content in the 0-5 cm layer within the protective system was0.038%, which was no more than that of dune crests. Sixyears later it was 0.154% and 9 years later it reached 0.216
which is close to that in the interdune. In 2001, the differenceof organic matter content between 0-5 cm layer and 5-10 cm
layer was not obvious. However in 2009 that of the 5-10 cm

49

Fig. 2. Comparison of soil moisture between natural dune andprotective system.

layer changed little but that of the 0-5 cm layer increased
significantly (Fig. 1(b)).
3.1.3. Soil water
In 2001 soil water in the protective system was far greaterthan that in natural dune surface, especially in the 20-40 cm
soil layer. The protective system provides a better watercondition for plant growth. In 2006, soil moisture in the 0-50
cm soil layer was close to that of natural dune surface, butbelow 50 cm depth it was significantly lower than that innatural dune. This may be related to such a fact that the rootsystem of vegetation inside the protective system had reached60-80 cm depth and a large amount of water was consumed.
In 2009, soil moisture below the 30 cm layer inside theprotective system was lower than that of natural dunes andexhibited a widespread aridity trend. The soil moisture in the20-30 cm soil layer was relatively higher because a rainfall
event occurred in the previous day of observation (Fig. 2).
3.2. Plant invasion in the protective system
3.2.1. Number of invasion plant species
A total of 48 plant species were identified in the naturaldune surface plot, including 6 life forms, namely dwarf trees,shrubs, sub-shrubs, perennial herbs, annuals and ephemeralplants. Among these, 30 species are ephemeral plants andbelong to 15 families. In interdunes and the lower part of theslope the coverage of shrubs dominated by Ephedra distachya
was 8.9-10.0% and ephemeral coverage reached 51.8% in
mid-May. In the upper parts of slopes the coverage of dwarf

Fig. 3. Number of plant species on natural dune surface and inprotective system from 2001 to 2009.

trees and shrubs dominated by Haloxylon persicum ranged
12.2-21.4% and that of ephemerals in mid-May reached 38.2%.
The crest was the strongest mobile zone, where the coverage ofplants was less than 10%. The ephemerals demonstrated
remarkable seasonal change, and they sprouted from the end ofMarch, and died away by early July.
From 2001 to 2009, the number of tree and shrub specieson the natural dune surface was 5 species, remaining
unchanged, while the number of perennial herb, annual andephemeral plant species changed slightly (Fig. 3(a)). During thesame period the number of invasive tree and shrub species inside
the protective system did not exceed 3 species. The number ofperennial and annual herbs did not exceed 9 species. However
the number of ephemeral plant species changed significantly (Fig.
3(b)). There were 8 species in 2001, and in 2002, 2006 and 2009
they reached 12, 21 and 21 species, respectively. In 2001 thenumber of ephemeral plant species occupied 27% of that ofnatural dune surface, 5 years later it reached 80% and gradually
approximated to the natural ground surface.
3.2.2. Variations of invasive plant density
Mean values of 1.4 plants/m2 were measured in theprotective system in 2001, and in 2006 and 2009 they reached
6.5 plants/m2 and 14 plants/m2, respectively. Of the total
number of invasive plants, ephemerals occupied 65% in 2001,and 85% in 2009. In 2001, the most abundant individuals

50Fig. 4. Plant density along the section in protective system from 2001
to 2009.

inside the protective system were Erodium oxyrrhynchum,which accounted for 59% of the total number of invasiveplants. In 2002, the invasive plants were dominated by
Erodium oxyrrhynchum as well. Trigonella tenella also
occurred and it accounted for 25% of the total number. By
2006 the main invasive ephemeral plants included Erodium
oxyrrhynchum, Lactuca tatarica, Trigonella tenella andChrozophora sabulosa, and they accounted for 11.4%, 10.2%,
9.5% and 8% of the total number, respectively. From 2001 to2009 the number of trees and shrubs in the section was nomore than 4 plants. In the first two years following theestablishment of the protective system the plant abundance was
far larger on the northern side than on the southern side of thechannel. Such distribution may be a result of NW and NE
winds that prevail in the region and therefore thewind-dispersed seeds dominated by Erodium oxyrrhynchum
etc. were first blown to the northern side. The plant
abundance outside the protective system was higher than inside
the protective system. This reflects the invasion processes ofplant entrance from the outer edge to the interior (Fig. 4).

4. Conclusion
In the Gurbantunggut Desert, straw checkerboard barriersand vegetation could effectively stabilize the disturbed sandsurface. Organic matter and extra-fine and silt materials
began to accumulate with time in the protective system. In
the initial stage following the protective system establishment,
the soil water condition was better than that on natural dune
surface. However, 10 years later they inevitably exhibited adecrease trend with extensive occurrence of crusts and herbage
invasion.
In 2001, of 15 invasive plant species ephemeral plants
constituted 8 species; 10 years later, of 33 invasive plant
species ephemeral plants constituted 21 species in protectivesystem. Invasive plant density in 2001 was 1.4 plants/m2.
Nine years later this increased to 14 plants/m2, of which
ephemerals accounted for 85% of the total number of invasiveplants. Erodium oxyrrhychun was the main invasive species.
Trees and shrubs were seldom found, which showed that theirnatural restoration is far more difficult than herbages.
The protective system played a great role in engineeringsafety in the Gurbantunggut Desert. However soil moisture
content in the artificial vegetation zone gradually decreased
with time. The plants that adapted to the local environment
could reproduce and maintain populations. With invasion of
biological crusts and shallow-rooted herbages, the simple
pioneering vegetation gradually evolved towards a complex
artificial-natural ecosystem. The development of artificial
vegetation needs additional investigation to refine techniquesin the future.
Acknowledgements
This research was funded by the National Natural ScienceFoundation of China (Grant No. 41371100 and 40771032), theState Key Development Program for Basic Research of China(Grant No. 2009CB421303).

References
Giles F.S., David S.G., Joanna E. (1995): Dune mobility andvegetation cover in the southwest Kalahari Desert. Earth
Surface Processes and Landforms, 20(6): 515-529.
Song Q.C., Wang G.Q. (2001): Computer simulation for blown
sand movement. Chinese Science Bulletin, 46(3): 254-256.
Wang X.Q., Wang T., Jiang J., Zhao C.J. (2005): On the sandsurface stability in the southern part of Gurbantunggut
Deser. Science in China (Series D), 34(8): 763-768.
Wu Y.H., Gao Q., Yu X.H. (2003): Distribution influencing
factors and monitoring of biological soil crusts. Chinese
Journal of Ecology, 22(3): 38-42.
Zhang L.Y., Chen C.D. (2002): On the general characteristicsof plant diversity of Gurbantunggut sandy desert. Acta
Ecologica Sinica, 22(11): 1923-1932.