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Topographical changes of ground surface affected by the shelterbelt along the Tarim Desert Highway

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Chinese Science Bulletin 2008年第S2期53卷 8-21页

作者： LI ShengYu LEI JiaQiang XU XinWen WANG HaiFeng FAN JingLong GU Feng QIU YongZhi XU Bo GONG Qing ZHENG Wei Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Graduate University of the Chinese Academy of Sciences Beijing 100049China Tarim Branch PetroChina Company LimitedKorla 841000China Weather Station of Tazhong Qiemo 841000China

To study the effects of sand protection project on modern aeolian landform, the types, distribution, and intensity of topographical changes of the ground surface affected by the shelterbelt along the Tarim Desert Highway were determined by measuring the deflation and deposition of sand surface in the Tazhong area located in the hinterland of the Taklimakan Desert. The results showed that (1) the newly-formed landform in sand protection systems is dominated by aeolian deposition including the small-scale Nabkha Dunes, the medium-scale sheet-like sand deposition and the large-scale ridge-like sand deposition. To some degree, aeolian deflation landform can also be formed in the open space in the shelterbelt. Furthermore, it is difficult for aeolian deflation landform to develop in a large scale in the interdunes. However, aeolian deflation landform can be developed in a large-scale on the windward slope of secondary dunes in longitudinal complex sand ridges; (2) on the windward side of the sand protection systems, both the morphology and strike of dwarf mobile dunes in the interdunes are changed by the sand-obstructing forest belts and the ridge-like sand deposition around it. The wind- ward slope of the ridge-like deposition around the sand-obstructing forest belt forms a stable ground surface. After being damaged by forward-moving dunes in a short period, the ground surface is re- covered gradually; (3) on the leeward side of the sand protection systems, aeolian deflations are formed widely. Particularly, the deflation depression is formed in the interdunes. In addition, the dunes in the region with highly topographic relief are cut flat by aeolian deflations; thereafter its relief of to- pography is reduced. The above analysis indicates that shelterbelts have obvious effects on the windward wind-sand flux in terms of dissipating energy and intercepting sand. With the recovery of wind velocity on the leeward side of the sand protection systems, the wind-sand flux gradually tends to be unsaturated; therefore the sa

关键词： aeolian landform deflation and deposition of sand surface shelterbelt Tarim Desert Highway

Plants water status of the shelterbelt along the Tarim Desert Highway

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Chinese Science Bulletin 2008年第S2期53卷 146-155页

作者： XU Hao ZHANG XiMing YAN HaiLong LIANG ShaoMin SHAN LiShan Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Institute of desertification control Ningxia Academy of Agriculture and Forestry ScienceYinchuan 750002China Foresty School Gansu Agricultural UniversityLanzhou 730070China

The plant water consumption and irrigation management are the core issue of the sustainable growing of the Tarim Desert Highway shelterbelt in the hyperaride Taklimakan Desert. The stem sap flow, water status and water consumption of shelterbelt plants were studied, then, the issue of the water save in the process of shelterbelt irrigation management was discussed by measuring the sap flow of shelterbelt plants with a stem sap flow gauge. The stem sap flow exhibited a distinct diurnal course with maximum values between 10:00 and 15:00, and minimum values between 00:00 and 03:00. Generally, sap flow was lower at night than during the day. The daily average stem sap flow of Calligonum arborescens, Tamarix ramosissima and Haloxylon ammodendron (diameter 1.9―2.0 cm) was 67.2 g·h-1, 77.05 g·h-1 and 61.54 g·h-1 respectively. The sap flow was influenced by environmental factors, and the solar radiation, wind velocity, temperature and relative humidity were significantly correlative with plant stem sap flow. The annual water consumption of 8-a Calligonum arborescens, Tamarix ramosissima and Haloxylon ammodendron was 1937.80 kg, 1253.39 kg and 1026.96 kg, while daily average water consumption was 9.69 kg, 6.27 kg and 5.13 kg respectively. Under drip irrigation, soil moisture content of the shelterbelt in different months indicated no obvious fluctuation, and soil moisture was adequate. The predawn and midday plant water potential reflected that the plant water status was in good conditions. There is still some water-saving space if optimizing the present water management, integrating water resources conservation and protection performance.

关键词： Tarim desert highway shelterbelt sap flow water consumption water status

Effect of the shelterbelt along the Tarim Desert Highway on air temperature and humidity

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Chinese Science Bulletin 2008年第S2期53卷 41-52页

作者： WANG HaiFeng LEI JiaQiang LI ShengYu FAN JingLong LI YingGang SUN ShuGuo CHANG Qing Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Graduate University of Chinese Academy of Sciences Beijing 100049China

The temperature and humidity of the shelterbelt micro-climate on both horizontal and vertical scales in the extremely drought area were measured with multiple HOBO temperature and humidity automatic observation equipments in the hinterland of the Taklimakan Desert. The results show that the shelterbelt ecosystem of the desert highway plays typical micro-climate adjustment rolesin stabilizing surface air temperature and increasing air humidity, and so on. Solar radiation significantly affects both temperature and humidity of surface layers, and it has a positive correlation with the temperature but a negative correlation with the air humidity. When it is cloudy, the weather has a great impact on keeping temperature and humidity in the shelterbelt. The shelterbelt also significantly influences the environment, and the micro-climate in the belt has an obvious characteristic of cooling and humidification: compared with the original sand area, the temperature in the shelterbelt is always lower and the humidity is always higher. Moreover, the temperature range at the shelterbelt edge is greater than that in the sand area, but the humidity is always higher. Our conclusion is that the vertical-effect range of temperature of the shelterbelts is 4 -10 m, and the humidity range is 6 to 8 m; the horizontal-effect range of temperature is 16 m and the humidity range is about 24 m.

关键词： shelterbelt extremely drought area micro-climate temperature and humidity boundary

The effect of salt stress on the chlorophyll level of the main sand-binding plants in the shelterbelt along the Tarim Desert Highway

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Chinese Science Bulletin 2008年第S2期53卷 109-111页

作者： XU XinWen XU HaiLiang WANG YanLing WANG XiaoJing QIU YongZhi XU Bo Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Institute of Environmental Engineering Xinjiang Agricultural UniversityUrumqi 830052China Tarim Branch PetroChina Company LimitedKorla 841000China

Based on the fact that only high saline water irrigated to the shelterbelt along the Tarim Desert Highway, the experiment about three species with six degree of salinity was carried out to analyze the relation between chlorophyll content and salt stress. The results show that: (1) the chlorophyll content of tree species decreases with aggravating the salt stress, which explains that salt stress can affect chlorophyll accumulation of three plants; (2) from chlorophyll content with different salinity, the chlorophyll content of three shrubs also has twice obvious decrease, which indicates that some plants adapt to salt stress. We divided salt resistance of the plant into three grades, namely the slight salt resistance, the heavy salt resistance and the extreme salt resistance; and (3) according to the experimental results, the salt stress of each plant was divided, which can provide theoretical guidance for constructing the shelterbelt along the Tarim Desert Highway.

关键词： artificial shelterbelt sand-binding plants salt stress chlorophyll

The vertical distribution of the root system of the desert highway shelterbelt in the hinterland of the Taklimakan Desert

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Chinese Science Bulletin 2008年第S2期53卷 79-83页

作者： WANG XiaoJing XU XinWen LEI JiangQiang LI ShengYu WANG YongDong Xinjiang Institute of Ecology and Geography Chinese Academic of SciencesUrumqi 830011China Graduate University of Chinese Academy of Sciences Beijing 100049China

In this work, the vertical distribution of the root system in the Tarim Desert Highway shelterbelt under high salinity water drip irrigation was investigated. The effect of site condition and shelterbelt age was studied. The root sample was collected by plant side soil column excavation. The root distribution was found to be dependent on soil texture, aspect, and plant age. In harden sand, the roots were mostly in the 0–40 cm soil. The root distribution is deep in flat sandy ground and ridge sand. In unit soil volume, the root weight of flat sandy ground was the highest. Compared with the shady slope, the sunny slope had much high total root weight, deeper root distribution, but less hair root. The root weight increased rapidly with the increase of the shelterbelt ages, and the most substantial increase was observed in the early years after forest implantation.

关键词： Tarim Desert Highway artificial shelterbelt root

Assessment of the effects of the shelterbelt on the soil temperature at regional scale based on MODIS data

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Journal of Forestry Research 2011年第1期22卷 65-70页

作者： DENG Rong-xin LI Ying ZHANG Shu-wen WANG Wen-juan SHI Xiao-liang Northeast Institute of Geography and Agriculture Ecology CASChangchun 130012 China. Graduated School of Chinese Academy of Science Beijing 100049China Department of Resources and Environmental Sciences Henan Universityof Finance and Economics Zhengzhou 450002 China

At present, the most researches on the protected effect of shelterbelt are on the basis of the two scales of forest belts and networks. However, with the further research on the global environmental change, more attention was paid to the regional climate effect of shelterbelt. In present study, we analyzed the temperature effect of the shelterbelt at regional scale by using the land surface temperature （LST） data from the moderate resolution imaging spectroradiometer （MODIS） at Yushu, Nong＇an, Dehui, and Fuyu in Jilin Province of China from March to October in 2008. Results show that the shelterbelt can increase the soil temperature of the protected farmland as compared with no shelterbelt zone, with the increment of 0.57oC per day in fine shelterbelt and 0.38oC per day in the normal shelterbelt. Moreover, the correlation analysis of the air temperature, precipitation and the soil type and the shelterbelt effect shows that the air temperature and precipitation are negatively correlated with the shelterbelt effects, that is, the more the temperature and precipitation are, the less the effect produced. While the impact of the soil types on the shelterbelt＇s effect is not very obvious as a whole. This paper draws significance in terms of analyzing the effects of the shelterbelt on the soil temperature at regional scale utilizing the remotely sensed data and GIS technique.

关键词： regional scale remote sensing shelterbelt temperature effect

Effects of natural covers on soil evaporation of the shelterbelt along the Tarim Desert Highway

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Chinese Science Bulletin 2008年第S2期53卷 137-145页

作者： ZHOU HongWei LI ShengYu SUN ShuGuo XU XinWen LEI JiaQiang LIU Shang DU WenYi YAN Zeng WANG YongChang Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Graduate University of the Chinese Academy of Sciences Beijing 100049China Tarim Branch PetroChina Company LimitedKorla 841000China Tuha Branch PetroChina Company LimitedKorla 839009China 不详

The control of soil evaporation is one of important approaches to save water. The artificially simulated evaporation experiments have been conducted in the hinterland of the Taklimakan Desert to reveal the effects of the natural covers on the soil evaporation of the Tarim Desert Highway shelterbelt as well as provide some insights in the efficient utilization of water resources and optimization of irrigation systems. The results showed that (1) All the covers, including the sand deposit, the salt crust, the litter, the sand-litter mixed layer and so on, can significantly inhibit the soil water evaporation. Specifically, the daily evaporation, the total evaporation, and the evaporation rate in covered sands were much smaller than that of sands without cover. The cover inhibition effects increased with the cover thickness. Particularly, the soil evaporation of the covered sands was less affected by external and internal factors than that of the bare sands. Moreover, the variation of daily evaporation of covered sands was smaller than that of bare sands. The cumulative evaporation varied linearly with time in the covered sands whereas it varied logarithmically in the bare sands. In addition, the soil evaporation in the bare sands showed significantly different characteristics in the early and late stages of the evaporation. (2) All the covers exhibited the significant inhibiting effect on the soil evaporation, and the inhibition efficiency increased logarithmically with the cover thickness. However, as the cover thickness was above a certain value, the increase in the inhibition efficiency was slow. Particularly, at a cover thickness of 2 cm, there was no obvious difference in the inhibition efficiency among all kinds of covers. The maximum inhibition efficiency as calculated from the daily evaporation on the first day of irrigation was: sand-litter mixed layer (79.92%) > litter layer (78.96%) > salt crust (75.58%) > sand bed (74.11%), whereas the average inhibiting efficiency as calculated from the cumulative soil

关键词： Taklimakan Desert shelterbelt irrigation cover soil evaporation inhibition efficiency

Algorithm Derivation of Winter Facies Wind Protection of shelterbelts Structural Parameters and Wind Permeability Coefficient

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Chinese Forestry Science and Technology 2012年第3期11卷 89-90页

作者： Wang Zhigang Ren Yu Experimental Center for Desert Forestry Chinese Academy of Forestry

To solve the problem in the absence of permeability algorithm in China’s forestry industry standard "Technical Specification for Oasis Shelter Belt Construction(LY/T 1682—2006)",by defining and calculating the forest structural parameters-porosityβ,stumpage surface porosity S",stumpage volume porosity V’,aboveground surface area density C,aboveground bulk density W,the relations among these structural parameters and their relations with wind permeability coefficientα,shelterbelt width D and mean diameter of branch d were calculated,which is expressed as:W=V’/D=dC/4 =dS’/4D=-πdlnβ/4D = -0.1πZdlnα/D.It is proofed that the main structural parameters have homogeneity and different structural parameters are of inheritance and consistency on the nature,there is no exclusivity in the strict sense,and is convertible under certain conditions,which is convenient for evaluating the wind-resistance effect of shelterbelt. A set of computational formulas for wind effect evaluation of farmland shelterbelt in dry and sandy area in northern China is derived.

关键词： farmland shelterbelt porosity stumpage porosity surface density bulk density wind permeability coefficient