Research on Coupling Relationship between Social Economy and Ecological Environment in Jinghe County of Aiby Lake Basin,Xinjiang

Based on the theory of sustainable development,using the theory and method of coupling relationship,the main city of Aiby Lake basin——Jinghe County in Xinjiang is selected. Based on the analyses of natural condition,population growth,land use type and ecological environment,the comprehensive evaluation index systems of socio-economic development level and eco-environment quality in Jinghe County are constructed. Using principal component analysis,a comprehensive evaluation of socio-economic development level and ecological environment quality in Jinghe County is conducted by combining with Excel. Their coupling relationship is studied,and quantitative coordination degree between social economy and ecological environment in Jinghe County is obtained. The results show that in recent 50 years,socio-economic development level in Jinghe County is rising,but the ecological environment quality is falling. Their coupling degree C changes during [- 1. 260, ＋ 0. 482],in other words,their coupling relationship is changing between ＂ reluctant coordination＂ and ＂ not coordination＂. After entering into the 21 stcentury,their coupling relationship is basically ＂ reluctant coordination＂. On this basis,the existing problems in the process of sustainable development in Jinghe County are analyzed,and the suggestions about promoting coordinated development between social economy and ecological environment are put forward.

Dried earth layers of artificial forestland in the Loess Plateau of Shaanxi Province

By determining the earth moisture content of artificial forestland between 0 and 6 m deep in the Loess Plateau of Shaanxi province, the vertical change of moisture content, distribution and formation causes of a dried earth layer are researched. The results show that the average moisture content is 9.3%-9.5% between 2 and 4 m under artificial forest of over 10 year＇s growth in Guanzhong Plain, and chronic weak dried earth layers are developed which show that the dried earth layers are distributed extensively on the Loess Plateau. The southern boundary of the dried earth layer has reached the northern foot of the Qinling Mountains. When precipitation reaches 600 mm, there are weak dried earth layers between 2 and 4 m under artificial forest of more than 10 years old. When the precipitation is between 400 and 500 mm, there are moderate dried earth layers. When precipitation is above 800 mm, there are no dried earth layers. There are no dried earth layers under meadow land, corn land and less than 5 years old of artificial forestland in central and southern parts of the Loess Plateau. The development of dried earth layers under cypress forest is weaker than broad-leaved forest. Under the same climatic conditions, the development of dried earth layers under the loess tableland is nearly at the same level as the 2nd and 3rd river terrace. Dried earth layers developed in membrane water zone, and the buried depth is small and motion velocity is slow in the Loess Plateau, which is the direct water factor of the formation of the dried earth layer, while differences of tree age and tree species are the plant factors that consumed much moisture. From the depth of the gravity water and the membrane water in Guanzhong Plain, it is clear that the formation cause of dried earth layers is mainly due to natural factors. The dried layers generally develop in middle-aged artificial forestland that consumed too much moisture, which is the general character of earth moisture in subhumid and semiarid zones. The appearance of dried layers doesn＇t show that the forest doesn＇t develop in this area; this is depended on their development intensity. Artificial forest of Chinese poplar, locust tree and Chinese scholartree consuming less water can be planted in the areas where dried earth layer developed weakly, but can not be planted in the areas where dried earth layer developed intensely.

Plant water use strategies in the Shapotou artificial sand-fixed vegetation of the southeastern margin of the Tengger Desert, northwestern China

Stable oxygen and hydrogen isotopic compositions(δ^(18)O and δD) of plant xylem water and its potential water sources can provide new information for studying water sources, competitive interactions and water use patterns of plants. The contributions of different water sources to three plants, Hedysarum scoparium(HS), Caragana Korshinskii(CK) and Artemisia ordosica(AO), were investigated in the artificial sand-fixed vegetation of Shapotou, the southeastern margin of the Tengger Desert of northwestern China, based on meteorological data and δ^(18)O and δD values of precipitation, groundwater, soil water and xylem water of HS, CK and AO. Our results indicated that soil water infiltration through precipitation was the main water source of the artificial sand-fixed vegetation. Obvious differences in soil water content and in δ^(18)O of soil water and xylem water were found among different seasons. No relationship was found between the δ^(18)O in plant xylem water and in soil water in January. The same water use patterns were found in CK, HS and AO in May, suggesting they have the same water sources. The different water sources of CK, HS and AO in August indicate that water competition occurred. In addition, the main water sources of CK, HS and AO in August mainly come from shallow soil water, while they use relatively deep soil water in May. This phenomenon is related to the differences of soil water content throughout soil profile, precipitation, transpiration and water competition under different growth periods. The water use patterns of CK, HS and AO respond to soil water content throughout the soil profile and their competition balance for water uptake during different growth season. The results indicate that these sandfixed plants have developed into a relatively stable stage and they are able to regulate their water use behavior as a response to the environmental conditions, which reinforces the effectiveness of plantation of native shrubs without irrigation in degraded areas.

Chronology of the Holocene loess-paleosol section and its deposition and pedogenesis on the south of Chinese Loess Plateau

Optically stimulated luminescence （OSL） dating for polymlneral fine-grained loess samples, collected in Laoguantai （LGT） section on the south of the Chinese Loess Plateau, was made by application of single-aliquot regenerative-dose （SAR） protocol. A ＇Double-SAW procedure in which aliquots are subjected to both infrared （IR） and blue stimulations was used and two sets of equivalent dose （De） determinations were produced and assumed to relate predominantly to feldspathic and quartz fine grain populations respectively, The OSL ages estimated from IRSL signals are smaller than those estimated from [post-IR] OSL signals due to the anomalous fading of feldspar IR signals, based on fading experiment, The young ages of the samples near ground surface may be originated from the post-depositional disturbance by the intensifying humanity＇s cultivation since 3.0 ka BP in the Guanzhong Basin, south of the Chinese Loess Plateau. Based on OSL dating, as well as field observations and stratigraphic correlation, we determine the chronology of the LGT Ioess-paleosol sequence. In combination with climate proxy records, it is indicated that aeolian loess deposition and pedogenesis underwent polyphase changes during the Holocene, likely to have been driven by shifts in the East Asian monsoon. This suggests that aeolian loess deposition is episodic and highly variable, with contributions from non-aeolian processes such as alluvial deposition found in the area.

The harmonious relationship between land use and environment in Xi’an

In this paper we adopt annual land use conditions change data, land sifting data, social, economic and population data and environment information of nine districts and four counties in Xi＇an city from 1980 to 2000 to analyze its structural and degree change of land use since the 1980s, and calculate the benefits and transformation of land use type. The results show that the non-agricultural land increased rapidly, especially the urban and rural residential spots and industrial and mining （RIM） land use increased mostly rapidly, an increase of 64%. Meanwhile, the intensity of land exploitation was accelerating, land was transformed to industries with better benefit and areas experiencing faster urbanization process. By analyzing the harmonious degree of land exploitation in economic and environmental aspects, we find out that the land use imbalance mainly existed in the municipal area of Xi＇an, and the imbalance index of land use based on GDP and non-agricultural population were respectively 12.37 and 14.67 in 2000, which were far higher than those in other regions. Nevertheless the environmental harmonious degree in the municipal area of Xi＇an ranges between 0.6 and 0.8, which was better than that of suburban area. Some proposals addressing to the problems of harmonious level in all scales, resources utilization, projects management and feasibility analysis and intensive urbanization are also put forward.

Sand particle lift-off velocity measurements and numerical simulation of mass flux distributions in a wind tunnel

Lift-off velocity of saltating sand particles in wind-blown sand located at 1.0 mm above the sand bed surface was measured using a phase Doppler particle analyzer in a wind tunnel. The results show that the probability distribution of lift-off velocity can be expressed as a lognormal function, while that of lift-off angle follows an exponential function. The probability distribution of lift-off angle conditioned for each lift-off velocity also follows an exponential function, with a slope that becomes steeper with increasing lift-off velocity. This implies that the probability distribution of lift-off velocity is strongly dependent on the lift-off angle. However, these lift-off parameters are generally treated as an independent joint probability distribution in the literature. Numerical simulations were carried out to investigate the effects of conditional versus independent joint probability distributions on the vertical sand mass flux distribution. The simulation results derived from the conditional joint probability distribution agree much better with experimental data than those from the independent ones. Thus, it is better to describe the lift-off velocity of saltating sand particles using the conditional joint probability distribution. These results improve our understanding of saltation processes in wind-blown sand.

Vertical distribution of soil moisture and surface sandy soil wind erosion for different types of sand dune on the southeastern margin of the Mu Us Sandy Land,China

Soil moisture is a critical state affecting a variety of land surface and subsurface processes. We report investigation results of the factors controlling vertical variation of soil moisture and sand transport rate of three types of dunes on the south- eastern margin of the Mu Us Sandy Land. Samples were taken from holes drilled to a depth of 4 m at different topographic sites on the dunes, and were analyzed for soil moisture, grain-size distribution and surface sediment discharge. The results show that： （1） The average soil moisture varies in different types of dunes, with the following sequences ordered from highest to lowest： in the shrubs-covered dunes and the trees-covered dunes the sequence is from inter-dunes lowland to windward slope to leeward slope. The average moisture in the bare-migratory sand dunes is sequenced from inter-dunes lowland to leeward slope to windward slope. （2） Vegetation form and surface coverage affect the range of soil moisture of different types of dunes in the same topographic position. The coefficient of variation of soil moisture for shrubs-covered dunes is higher than that of other types of dune. （3） The effect of shrubs on dune soil moisture is explained in terms of the greater ability of shrubs to trap fine-grained atmospheric dust and hold moisture. （4） The estimated sand transport rates over sand dunes with sparse shrubs are less than those over bare-migratory dunes or sand dunes with sparse trees, indicating that shrubs are more effective in inhibiting wind erosion in the sandy land area.

Luminescence chronology and age model application for the upper part of the Chumbur-Kosa loess sequence in the Sea of Azov, Russia

A reliable chronology is essentially critical for correlating loess records with other paleoenvironmental time series, as well as for continuing improvements in the reconstruction of paleoenvironment and paleoclimate changes. It is exactly that the scarcity of chronologies across the Sea of Azov has limited the interpretation of climatic and environmental information in the East European Plain. In view of this, this paper conducted an exploratory study to investigate whether the optically stimulated luminescence(OSL) dating of medium-grained quartz could be used to obtain a set of chronologies and the age models could be used to establish an independent time scale since the Late Pleistocene for the Sea of Azov loess. The results showed that an internally consistent set of optical ages for the Azov loess deposited up to ~76 ka. In addition, the ages developed based on magnetic susceptibility and grain size ages models showed good comparability with independent OSL ages at an acceptable range, suggesting that it might be practicable to establish an independent time scale using age models at the Sea of Azov loess, at least for the uppermost part of the Chumbur-Kosa section. Comparison with the ages based on two age models,the grain size ages using fine-grain fractions may provide a more reliable chronological sequence at the Azov loess since the Late Pleistocene. With the help of absolute ages and climate proxies(magnetic susceptibility and grain size), paleoclimatic change in the Sea of Azov have been traced for the Late Pleistocene.

Land Eco-sensitivity Assessment of Ecological Cities Based on LUCC

Land eco-sensitivity assessment is an important method in analyzing regional eco-environmental safety. This article is based on the studies of land use and coverage change (LUCC) with the interpretation result from Landsat images. It analyzes the land use degree of Shangluo City and gives the land eco-sensitivity classification, which includes soil and water conservation, disaster prevention and eco-environmental protection. Then an improved classification model is taken through the gray model and the variation coefficient. By comparing sensitivity in each level of land use degree change, the ecological recovery mode in study area is analyzed. The results show: the land use degree in Shangluo City has been declining from 1990 to 2009, with large area converted form cropland to forest, environment becomes better; the sensitivities of zoning based on the index level shows the medium sensitive area was largest. According to the variation coefficient gives the more reasonable proportion, the zoning was improved based on uncertainties. Because of the least amount of land use degradation area was taken in high sensitive region, it is considered that the ecological construction model in study area was still worth discussing. The healthy ecological development mode is proposed that low sensitive region should be protected while high sensitive region should receive high attention, so as to further improve the regional ecological security and improve the living environment efficiently.

Natural radioactive environment of urban soils in Shihezi, China

Radionuclides, such as 238U, 232Th and 40K, can be found in urban soil. To evaluate the natural radioactivity in the environment, soil samples were collected form Shihezi city and radioisotope concentrations were determined by X-ray fluorescence. The dose rate of urban soil (mGy per year, mGy/a) was calculated. The results indicate that the U, Th and K concentrations of the urban soils were, respectively, 1.2-3.2 mg/kg, 6.4-12.3 mg/kg and 2.05%-2.24%, with the mean values of 2.47 mg/kg, 10.47 mg/kg and 2.16 %. Dose rates of urban soils were 10.04-19.55 mGy/a with the mean value of 16.31 mGy/a. This dose rate is the perfect and maximum value of natural radiation in soil and different with the air absorbed dose rate from terrestrial γ-rays. The mean value of air absorbed dose rate was about 57.42 nGy/h. The annual effective dose rate in air was about 0.07 mSv/a and the average value of Raeq in urban soil was 120.37 Bq/kg. The relative contribution of α particle to the dose rate is higher than that derived from β- and γ-rays in the urban soils.

Study on the Flow of Rural Labor Force and the Contribution of Terrain Factor in Shaanxi,China

The flow of rural labor to urban is a significant phenomenon in China during the last 20 years.In spite of many researches focus on the driving force of economy,terrain is an important index in the rural development.There is a question that whether the flow of rural labor has some relationships with terrain.The study used the relief degree of land surface (RDLS) as terrain index,and the cost distance model and the center of gravity model to analyze the relationship between terrain and labor flows.The results indicated:(1) In the last 20 years,the rural labor force was not simply flowing to the low terrain region in Shaanxi province.And the RDLS was constantly strengthening the influence on the movement.(2) The RDLS was low in Guanzhong region,and the translation of rural labors relatively was not significant.Since North Shaanxi act as the energy industry base,the number of rural labors there increased faster than in South Shaanxi.(3) The movements of economical centers took an important role in the change of rural labor centers,and terrain factors also showed a high correlation with them.It is found that the lower of the terrain index,the higher of the land intensive degree,the more intensive of nonagriculturalization process.

Aesthetic evaluation of yardang landforms landscape:the Dunhuang Yardang National Geo-park example

Dunhuang Yardang National Geo-park, situated in the Gansu Province of northwestern China （40°25′36″N-40°33′10″N, 93°00′00″E-93°13′30″E）, was chosen as a research locality of aesthetics evaluation of yardang landforms landscape. The yardang landforms landscape is a composite structural system of patch-corridor-matrix, with four landscape unit elements as dense group, sparse group, single body and remnant. The study of the landscape aesthetics spatial pattern of Dunhuang Yardang National Geo-park shows that yardang dense group, sparse group and single body provide the greatest contribution to the aesthetic value of yardang landforms landscape. Yardang bodies are scarce, unique, irreplaceable, and priceless resources in yardang landforms areas. However, they are easily destroyed under the influence of the natural and artificial factors. Therefore, when the tourism potential of yardang landforms landscape is exploited, the protection should be fully improved.

Comparison between TVDI and CWSI for drought monitoring in the Guanzhong Plain,China

Temperature vegetation dryness index （TVDI） and crop water stress index （CWSI） are two commonly used remote sens- ing-based agricultural drought indicators. This study explored the applicability of monthly moderate resolution imaging spectroradiometer （MODIS） normalized difference vegetation index （NDVI） and land surface temperature （LST） data for agricultural drought monitoring in the Guanzhong Plain, China in 2003. The data were processed using TVDI, calculated by parameterizing the relationship between the MODIS NDVI and LST data. We compared the effectiveness of TVDI against CWSI, derived from the MOD16 products, for drought monitoring. In addition, the surface soil moisture and monthly pre- cipitation were collected and used for verification of the results. Results from the study showed that： （1） drought conditions measured by TVDI and CWSI had a number of similarities, which indicated that both CWSI and TVDI can be used for drought monitoring, although they had some discrepancies in the spatiotemporal characteristics of drought intensity of this region; and （2） both standardized precipitation index （SPI） and SM contents at the depth of 10 and 20 cm had better correlations to CWSI than to TVDI, indicating that there were more statistically significant relationships between CWSI and SPI/SM, and that CWSI is a more reliable indicator for assessing and monitoring droughts in this region.

Comparison of transpiration between different aged black locust(Robinia pseudoacacia)trees on the semi-arid Loess Plateau,China

Black locust （Robinia pseudoacacia） is widely planted throughout the semi-arid Loess Plateau of China. The spatial distribution of this species at different ages is highly heterogeneous due to restoration and management practices. In this study, we aimed to compare the transpiration levels between different aged black locusts at the tree and stand scales, clarifying the physiological status of this species with different ages. Black locust trees with two representative age classes （12 and 28 years） were selected in the Yangjuangou catchment on the semi-arid Loess Plateau. Sap flux density （Fd） and environmental variables （solar radiation, air temperature, relative humidity and soil water content） were simultaneously monitored throughout the growing season of 2014. Tree transpiration （Et） was the product of Fd and sapwood area （As）, and stand transpiration （Ec） was calculated basing on the stand sap flux density （Js） and stand total sapwood area （AsT）. Stomatal conductance （gs） was measured in a controlled environment and hydraulic conductance was estimated using the relationship between transpiration rate and vapor pressure deficit （VPD）. Our results showed that Et and Ec were higher in the 28-year-old stand than in the 12-year-old stand. The gs and hydraulic conductance of 28-year-old trees were also higher than those of 12-year-old trees, and the two parameters were thus the causes of variations in transpiration between different age classes. After rainfall, mean Fd increased by 9% in 28-year-old trees and by 5% in 12-year-old trees. This study thus suggests that stand age should be considered for estimating transpiration at the catchment and region scales in this area. These results provide ecophysiological evidences that the older black locust trees had more active physiological status than the younger ones in this area. These findings also provide basic information for the management of water resources and forests on the semi-arid Loess Plateau.

Improved Land Use and Leaf Area Index Enhances WRF-3DVAR Satellite Radiance Assimilation： A Case Study Focusing on Rainfall Simulation in the Shule River Basin during July 2013

The application of satellite radiance assimilation can improve the simulation of precipitation by numerical weather prediction models. However, substantial quantities of satellite data, especially those derived from low-level（surface-sensitive）channels, are rejected for use because of the difficulty in realistically modeling land surface emissivity and energy budgets.Here, we used an improved land use and leaf area index（LAI） dataset in the WRF-3 DVAR assimilation system to explore the benefit of using improved quality of land surface information to improve rainfall simulation for the Shule River Basin in the northeastern Tibetan Plateau as a case study. The results for July 2013 show that, for low-level channels（e.g., channel 3）,the underestimation of brightness temperature in the original simulation was largely removed by more realistic land surface information. In addition, more satellite data could be utilized in the assimilation because the realistic land use and LAI data allowed more satellite radiance data to pass the deviation test and get used by the assimilation, which resulted in improved initial driving fields and better simulation in terms of temperature, relative humidity, vertical convection, and cumulative precipitation.

Aesthetic value of aeolian geomorphosites in the Kumtagh Desert,China

Tourism development of aeolian geomorphosites in the Kumtagh Desert is beneficial to both harmonious development of human-nature relationship and the sustainable development of the tourist industry in the Kumtagh Desert and its sur- rounding area. This paper adopts some research methods including field observation, expert assessment, and systematic investigation to analyze and evaluate the aesthetic value of aeolian geomorphosites in the Kumtagh Desert from three aspects of＂Beauty of Morphology＂, ＂Beauty of Color＂ and ＂Beauty of Forms＂. This research is a creative work in the field of aeolian geomorphosites combining the method of aeolian geomorphology and tourism geography.

Climate and soil moisture environment during develop-ment of the fifth palaeosol in Guanzhong Plain

Based on weathering characteristics of the fifth palaeosol layer (S5) of four sections in Guanzhong Plain, the thickness of the weathered profile of the paleosol is determined to be greater than the ordi- nary soil, a weathered and leached loess layer thicker than 2 m. The distribution depth of the red argil- lans, the weathered and leached loess layer, Fe2O3, CaCO3 and Sr content under the S5 all indicate that the precipitation in Guanzhong Plain was over 900 mm at that time. The distribution depth of gravity water zone reached 4.2 m at least, and the soil moisture content was generally more than 20% within the range of 4.2 m. At that time there was sufficient soil moisture and no dried earth layer developed in Guanzhong Plain, suitable for the forest to develop. When this soil developed, the mean annual pre- cipitation was more than the annual soil moisture evaporation. The value of soil moisture balance was positive and the atmospheric precipitation could supply the underground water normally. Soil water was weak acidic in the middle and late stages when S5 developed in Guanzhong Plain. It was a kind of subtropical climate and even more humid and warmer than the northern edge of the subtropical climate zone in Guanzhong Plain when the S5 developed. At that time the subtropical climate was prevailing over the northern side and southern side of Qingling Mountains, showing the Mountains no longer to be the boundary between the subtropical zone and the temperate zone in China. The summer monsoon acted intensely and could go over Qingling Mountains frequently bring abundant precipitation.

基于旅西日本游客旅游选择行为的西安旅游市场分析

根据在全国六大旅游热点城市所做的旅游市场调查的数据结果,对旅西日本游客的旅游选择行为进行了研究,同时进一步有针对性地对西安日本客源市场进行了SWOT分析,在此基础上,对西安旅游业的发展提出了相关对策建议。

Response of vegetation restoration to climate change and human activities in Shaanxi-Gansu- Ningxia Region

The ＂Grain for Green Project＂ initiated by the governments since 1999 were the dominant contributors to the vegetation restoration in the agro-pastoral transitional zone of northern China. Climate change and human activities are responsible for the improvement and degradation to a certain degree. In order to monitor the vegetation variations and clarify the causes of rehabilitation in the Shaanxi-Gansu-Ningxia Region, this paper, based on the MODIS-NDVI and climate data during the period of 2000-2009, analyzes the main charac- teristics, spatial-temporal distribution and reasons of vegetation restoration, using methods of linear regression, the Hurst Exponent, standard deviation and other methods. Results are shown as follows. （1） From 2000 to 2009, the NDVI of the study area was improved progres- sively, with a linear tendency being 0.032/10a, faster than the growth of the Three-North Shelter Forest Program （0.007/10a） from 1982 to 2006. （2） The vegetation restoration is characterized by two fast-growing periods, with an ＂S-shaped＂ increasing curve. （3） The largest proportion of the contribution to vegetation restoration was observed in the slightly improved area, followed by the moderate and the significantly improved area; the degraded area is distributed sporadically over southern part of Ningxia Hui Autonomous Region as well as eastern Dingbian of Shaanxi province, Huanxian and Zhengyuan of Gansu province. （4） Climate change and human activities are two driving forces in vegetation restoration; more- over anthropogenic factors such as ＂Grain for Green Project＂ were the main causes leading to an increasing trend of NDVI on local scale. However, its influencing mechanism remains to be further investigated. （5） The Hurst Exponent of NDVI time series shows that the vegetation restoration was sustainable. It is expected that improvement in vegetation cover will expand to the most parts of the region.