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| 1 | Vegetation dynamics and its response to climate change in Central Asia显示文摘The plant ecosystems are particularly sensitive to climate change in arid and semi-arid regions. However, the responses of vegetation dynamics to climate change in Central Asia are still unclear. In this study, we used the normalized difference vegetation index(NDVI) data to analyze the spatial-temporal changes of vegetation and the correlation of vegetation and climatic variables over the period of 1982–2012 in Central Asia by using the empirical orthogonal function and least square methods. The results showed that the annual NDVI in Central Asia experienced a weak increasing trend overall during the study period. Specifically, the annual NDVI showed a significant increasing trend between1982 and 1994, and exhibited a decreasing trend since 1994. The regions where the annual NDVI decreased were mainly distributed in western Central Asia, which may be caused by the decreased precipitation. The NDVI exhibited a larger increasing trend in spring than in the other three seasons. In mountainous areas, the NDVI had a significant increasing trend at the annual and seasonal scales; further, the largest increasing trend of NDVI mainly appeared in the middle mountain belt(1,700–2,650 m asl). The annual NDVI was positively correlated with annual precipitation in Central Asia, and there was a weak negative correlation between annual NDVI and temperature. Moreover, a one-month time lag was found in the response of NDVI to temperature from June to September in Central Asia during 1982–2012. | YIN Gang HU Zengyun CHEN Xi TIYIP Tashpolat | 2016 | Journal of Arid Land2016，8，3： | 13 |
| 2 | Vegetation fractional coverage change in a typical oasis region in Tarim River Watershed based on remote sensing显示文摘Vegetation fractional coverage(VFC) is an important index to describe and evaluate the ecological system.The vegetation index is widely used to monitor vegetation coverage in the field of remote sensing(RS).In this paper,the author conducted a case study of the delta oasis of Weigan and Kuqa rivers,which is a typical saline area in the Tarim River Watershed.The current study was based on the TM/ETM+ images of 1989,2001,and 2006,and supported by Geographic Information System(GIS) spatial analysis,vegetation index,and dimidiate pixel model.In addition,VBSI(vegetation,bare soil and shadow indices) suitable for TM/ETM+ images,constructed with FCD(forest canopy density) model principle and put forward by ITTO(International Tropical Timber Organization),was used,and it was applied to estimate the VFC.The estimation accuracy was later proven to be up to 83.52%.Further,the study analyzed and appraised the changes in vegetation patterns and revealed a pattern of spatial change in the vegetation coverage of the study area by producing the map of VFC levels in the delta oasis.Forest,grassland,and farmland were the three main land-use types with high and extremely-high coverage,and they played an important role in maintaining the vegetation.The forest area determined the changes of the coverage area,whereas the other two land types affected the directions of change.Therefore,planting trees,protecting grasslands,reclaiming farmlands,and controlling unused lands should be included in a long-term program because of their importance in keeping regional vegetation coverage.Finally,the dynamic variation of VFC in the study area was evaluated according to the quantity and spatial distribution rendered by plant cover digital images to deeply analyze the reason behind the variation. | Fei ZHANG Tashpolat TIYIP JianLi DING Mamat SAWUT Verner Carl JOHNSON NigaraTASHPOLAT DongWei GUI | 2013 | Journal of Arid Land2013，5，1： | 12 |
| 3 | Study on Soil Salinization Information in Arid Region Using Remote Sensing Technique显示文摘Extracting information about saline soils from remote sensing data is useful, particularly given the environmental significance and changing nature of these areas in arid environments. One interesting case study to consider is the delta oasis of the Weigan and Kuqa rivers, China, which was studied using a Landsat Enhanced Thematic Mapper Plus (ETM+) image collected in August 2001. In recent years, decision tree classifiers have been successfully used for land cover classification from remote sensing data. Principal component analysis (PCA) is a popular data reduction technique used to help build a decision tree; it reduces complexity and can help the classification precision of a decision tree to be improved. A decision tree approach was used to determine the key variables to be used for classification and ultimately extract salinized soil from other cover and soil types within the study area. According to the research, the third principal component (PC3) is an effective variable in the decision tree classification for salinized soil information extraction. The research demonstrated that the PC3 was the best band to identify areas of severely salinized soil; the blue spectral band from the ETM+ sensor (TM1) was the best band to identify salinized soil with the salt-tolerant vegetation of tamarisk (Tamarix chinensis Lour); and areas comprising mixed water bodies and vegetation can be identified using the spectral indices MNDWI (modified normalized difference water index) and NDVI (normalized difference vegetation index). Based upon this analysis, a decision tree classifier was applied to classify landcover types with different levels of soil saline. The results were checked using a statistical accuracy assessment. The overall accuracy of the classification was 94.80%, which suggested that the decision tree model is a simple and effective method with relatively high precision. | Tashpolat Tiyip | 2011 | Agricultural Sciences in China2011，10，3： | 10 |
| 4 | Stand structure and height-diameter relationship of a degraded Populus euphratica forest in the lower reaches of the Tarim River, Northwest China显示文摘Understanding stand structure and height-diameter relationship of trees provides very useful information to establish appropriate countermeasures for sustainable management of endangered forests. Populus euphratica, a dominant tree species along the Tarim River watershed, plays an irreplaceable role in the sustainable development of regional ecology, economy and society. However, as the result of climate changes and human activities, the natural riparian ecosystems within the whole river basin were degraded enormously, particularly in the lower reaches of the river where about 320 km of the riparian forests were either highly degraded or dead. In this study, we presented one of the main criteria for the assessment of vitality of P. euphratica forests by estimating the defoliation level, and analyzed forest structure and determined the height-diameter(height means the height of a tree and diameter means the diameter at breast height(DBH) of a tree) relationship of trees in different vitality classes(i.e. healthy, good, medium, senesced, dying, dead and fallen). Trees classified as healthy and good accounted for approximately 40% of all sample trees, while slightly and highly degraded trees took up nearly 60% of total sample trees. The values of TH(tree height) and DBH ranged from 0–19 m and 0–125 cm, respectively. Trees more than 15 m in TH and 60 cm in DBH appeared sporadically. Trees in different vitality classes had different distribution patterns. Healthy trees were mainly composed more of relatively younger trees than of degraded tress. The height-diameter relationships differed greatly among tress in different vitality classes, with the coefficients ranging from 0.1653 to 0.6942. Correlation coefficients of TH and DBH in healthy and good trees were higher than those in trees of other vitality classes. The correlation between TH and DBH decreased with the decline of tree vitality. Our results suggested that it might be able to differentiate degraded P. euphratica trees from healthy trees by determining the height-diameter correlation coefficient, and the coefficient would be a new parameter for detecting degradation and assessing sustainable management of floodplain forests in arid regions. In addition, tree vitality should be taken into account to make an accurate height-diameter model for tree height prediction. | AISHAN Tayierjiang HALIK ümüt Florian BETZ TIYIP Tashpolat DING Jianli NUERMAIMAITI Yiliyasijiang | 2015 | Journal of Arid Land2015，7，4： | 10 |
| 5 | Possible solar forcing of climate variability in the past 4000 years inferred from a proxy record at the southern margin of Tarim Basin显示文摘A ca. 4000a decadal-resolution climate proxy record of the mean grain-size from a lake (or mash) sediment at the southern margin of the Tarim Basin, correlates visu- ally with the atmospheric △14C, record from tree ring (residual △14C, solar proxy)and the GISP2 ice core 8O record (tem- peralure proxy). In general, △14 C maxima (solar minima) are coincident With cold (wet) periods in the study area and cold periods in the (;reenland ice core. Power spectrum analysis revealed statislically significant periodicities of 196a, 121a, 97a, 62a, 45a and 33—30a, which are similar to those prin- cipal solar-oscillation periods as inferred from the atmos- pheric radiocarbon and other proxy records. Possible solar forcing is addressed to be the main driving forcing of climate change in the southern margin of Tarim Basin. | ZHONGWei WANGLiguo Tyip·Tashpolat XIONGHeigang SHUQiang | 2004 | Chinese Science Bulletin2004，49，11： | 9 |
| 6 | The Effects of the Chemical Components of Soil Salinity on Electrical Conductivity in the Region of the Delta Oasis of Weigan and Kuqa Rivers,China显示文摘In order to assess the effects of chemical properties of soil salinity on electrical conductivity of 1:5 soil/water extract (EC1:5), the study focused on revealing the main chemical factors contributing to EC of soil extracts and their relative importance. The relationship between EC1:5 and the chemical properties of soil salinity in the delta oasis of Weigan and Kuqa rivers, China, were studied using path coefficient analysis, a path analysis method. We studied each key element affecting EC1:5 either directly or indirectly. The results obtained show that the salt content, total dissolved solids (TDS), and the sum of the sodium ion concentration and the kalium ion concentration are the most influential factors on 1:5 soil/ water extract (EC1:5) in the 0-10 cm and the 30-50 cm soil layer. The results show that the sequence of direct path coefficients in the 0-10 cm and the 30-50 cm soil layers on soil conductivity is TDS→Na+ + K+→Salt content→Ca2+→Cl-→the sodium dianion ratio (SDR)→pH→SO42-→HCO3-→Mg2+→the soluble sodium percentage (SSP)→sodium absorption ratio (SAR) and TDS→Salt content→Na+ + K+→Ca2+→SDR→Mg2+→HCO3-→SSP→pH→SO42-→SAR→Cl-. The salt content, chlorine ion, and SAR are the main factors affecting 1:5 soil/water extract (EC1:5) in the 10-30 centimeter soil layer. The order of direct path coefficients result is as follows: Salt content→Cl-→SAR→SSP→TDS→Ca2+→Mg2+ = SO42-→HCO3-→pH→SDR→Na+ + K+. Moreover, the effects of HCO3-, pH were very weak. Though the direct path coefficients between EC1:5 and SAR, SO42- and Ca2+ were not high, influence of other chemical factors caused the coefficients to increase, making the summation of their direct and indirect path coefficients relatively high. The models of the different soil layers were structured separately. Evidences showed that multiple regression relations between EC1:5 and most of the primary factors had sound reliability and very good accuracy. The research results can serve as a reference to the scientific management amelioration and utilization of saline in the Delta Oasis of Weigan and Kuqa rivers. | ZHANG Fei Tashpolat Tiyip DING Jian-li Gregory N Taff HE Qi-sheng | 2009 | Agricultural Sciences in China2009，8，8： | 4 |
| 7 | A Method of Soil Salinization Information Extraction with SVM Classification Based on ICA and Texture Features显示文摘Salt-affected soils classification using remotely sensed images is one of the most common applications in remote sensing,and many algorithms have been developed and applied for this purpose in the literature.This study takes the Delta Oasis of Weigan and Kuqa Rivers as a study area and discusses the prediction of soil salinization from ETM +Landsat data.It reports the Support Vector Machine(SVM) classification method based on Independent Component Analysis(ICA) and Texture features.Meanwhile,the letter introduces the fundamental theory of SVM algorithm and ICA,and then incorporates ICA and texture features.The classification result is compared with ICA-SVM classification,single data source SVM classification,maximum likelihood classification(MLC) and neural network classification qualitatively and quantitatively.The result shows that this method can effectively solve the problem of low accuracy and fracture classification result in single data source classification.It has high spread ability toward higher array input.The overall accuracy is 98.64%,which increases by10.2% compared with maximum likelihood classification,even increases by 12.94% compared with neural net classification,and thus acquires good effectiveness.Therefore,the classification method based on SVM and incorporating the ICA and texture features can be adapted to RS image classification and monitoring of soil salinization. | ZHANG Fei TASHPOLAT Tiyip KUNG Hsiang-te DING Jian-li MAMAT.Sawut VERNER Johnson HAN Gui-hong GUI Dong-wei | 2011 | Agricultural Science & Technology2011，12，7： | 3 |
| 8 | Characteristics of soil seed banks at different geomorphic positions within the longitudinal sand dunes of the Gurbantunggut Desert, China显示文摘Understanding the characteristics of soil seed banks in sand dunes is crucial to stabilize the dune systems and maintain the plant populations in deserts. In this study, we conducted a survey investigation in the field and a seed germination experiment in the laboratory to explore the characteristics of soil seed banks at various geomorphic positions of longitudinal sand dunes in the Gurbantunggut Desert, China. Totally, 17 plant species belonging to 17 genera and 9 families were identified in soil seed banks, and 35 plant species belonging to 34 genera and 17 families were identified in aboveground vegetation. Plant species richness in soil seed banks decreased with increasing soil depth. The highest species richness was presented in the upper slope of the windward slope and the lowest species richness was presented in the base of the windward slope. There was no significant difference in seed density of soil seed banks among the examined seven geomorphic positions. The highest seed density occurred in the lower slope of the leeward slope while the lowest occurred in the crest. Moreover, seed density decreased with increasing soil depth, being the highest in the upper soil layer(0–2 cm). For both soil seed banks and aboveground vegetation, there was no significant difference in Simpson's diversity index among the seven geomorphic positions; however, Shannon-Wiener diversity index and Pielou's evenness index showed significant differences among the seven geomorphic positions. Those results showed that although there was no significant difference in seed density of soil seed banks among the seven geomorphic positions, the geomorphic positions significantly affected the species richness, diversity and distribution of soil seed banks. Therefore, understanding the characteristics of soil seed banks at different geomorphic positions of sand dunes is essential to vegetation restoration or reestablishment. Furthermore, the Jaccard's similarity coefficients of plant species between soil seed banks and aboveground vegetation at the seven geomorphic positions were low, suggesting that vegetation restoration or reestablishment processes should be promoted through adding seeds to surface layers. | JIA Fengqin Tashpolat TIYIP WU Nan TIAN Changyan ZHANG Yuanming | 2017 | Journal of Arid Land2017，9，3： | 3 |
| 9 | Optimal root system strategies for desert phreatophytic seedlings in the search for groundwater显示文摘Desert phreatophytes are greatly dependent on groundwater, but how their root systems adapt to different groundwater depths is poorly understood. In the present study, shoot and root growths of Alhagi sparsifolia Shap. seedlings were studied across a gradient of groundwater depths. Leaves, stems and roots of different orders were measured after 120 days of different groundwater treatments. Results indicated that the depth of soil wetting front and the vertical distribution of soil water contents were highly controlled by groundwater depths. The shoot growth and biomass of A. sparsifolia decreased, but the root growth and rooting depth increased under deeper groundwater conditions. The higher ratios of root biomass, root/shoot and root length/leaf area under deeper groundwater conditions implied that seedlings of A. sparsifolia economized carbon cost on their shoot growths. The roots of A. sparsifolia distributed evenly around the soil wetting fronts under deeper groundwater conditions. Root diameters and root lengths of all orders were correlated with soil water availabilities both within and among treatments. Seedlings of A. sparsifolia produced finer first- and second-order roots but larger third- and fourth-order roots in dry soils. The results demonstrated that the root systems of desert phreatophytes can be optimized to acquire groundwater resources and maximize seedling growth by balancing the costs of carbon gain. | LI Changjun ZENG Fanjiang ZHANG Bo LIU Bo GUO Zichun GAO Huanhuan TIYIP Tashpolat | 2015 | Journal of Arid Land2015，7，4： | 2 |
| 10 | Modified perpendicular drought index (MPDI): a real-time drought monitoring method显示文摘 | Abduwasit Ghulam Qiming Qin Tashpolat Teyip Zhao-Liang Li | 2007 | ISPRS Journal of Photogrammetry and Remote Sensing2007，，2： | 2 |
| 11 | The Change of Land Use/Cover and Characteristics of Landscape Pattern in Arid Areas Oasis: An Application in Jinghe, Xinjiang显示文摘This paper uses 3S technology in macroscopic. Combining the integrated technology of ecological quantity analytical method with GIS technology through ArcGIS and Fragstats, the authors study the images of 1972, 1990, 2001, and 2005 and obtained land use data in Jinghe County. Then, the change of land use/cover and landscape pattern had been analyzed in the Jinghe County of Xinjiang. The conclusions were as follows: (1) The trend of LUCC is that the area of oasis expands slowly in nearly 33 years between 1972 to 2005 in Jinghe County. (2) The water area is mainly influenced by Ebinur Lake, so the area expands a little in this period. (3) The area of salinization-land expands at first and reduces later. The area of sand land decreases and the other land class increases, while the probability of transfer is always high. (4) Landscape change is also obvious throughout the decades. Overall, landscape density increases, the largest path index decreases at first and expends later, the weight area index decreases, and the shape of landscape becomes regulated. The nearest distances, the degrees of reunite, and outspread decreases. It shows that the connection of the main path in 1972 is better than 2005, wherein the patch becomes more complex. From the changes of Shannon’s Diversity Index and Shannon’s Evenness Index, we know that the diversity of landscape and the Interspersion Juxtaposition Index increase. The degree of diversity landscape and fragmentation increase also shows that the land uses become more complex. All in all, it is essential to intensify the spatial relationships among landscape elements and to maintain the continuity of landscape ecological process and pattern in the course of area expansion. | TASHPOLAT·Tiyip Hsiang-te KUNG | 2010 | Geo-Spatial Information Science2010，13，3： | 2 |
| 12 | Modified perpendicu- lar drought index (MPDI) :a real-time drought monitoring method显示文摘 | ABDUWASIT G QIMING Q TASHPOLAT T | 2007 | IS- PRS Joumal of Photogrammetry & Remote Sensing2007，62，： | 1 |
| 13 | A soil quality assessment underdifferent land use types in Keriya river basin, Southern Xinjiang, China显示文摘 | Gong L Ran QY He GX Tashpolat T | 2015 | Soil Tillage Res2015，146，： | 1 |
| 14 | Dielectric properties of saline soil based on a modified Dobson dielectric model显示文摘Soil salinization is a major concern for agricultural development in arid areas. In this paper, a modified Dobson dielectric model was applied to simulate the dielectric constant of saline soil in the Ugan-Kuqa river delta oasis of Xinjiang Uygur autonomous region, northwestern China. The model performance was examined through analyzing the influences of its parameters on the soil dielectric constant and the relationship between radar backscattering coefficient and the dielectric constant of saline soil. The results of the study indicate that:(1) The real part of the soil dielectric constant is affected by soil water content at low radar frequencies; the imaginary part is closely related with both the soil water content and soil salt content.(2) The soil water and salt contents are related with the coefficient of dialectical loss, which is consistent with the natural conditions of saline soil in arid areas and provides valuable references for the study of soil dielectric properties.(3) The changes of soil water content and soil salt content have instant influences on the dielectric constant of saline soil. Subsequently, the radar backscattering coefficient is affected to respond to the dielectric constant of saline soil. The radar backscattering coefficient is most responsible to the radar's cross polarization pattern with a correlation coefficient of R2=0.75. This study provides a potential method to monitor soil salinization and soil water content by using a soil dielectric model and radar techniques. | Nigara TASHPOLAT DING Jianli YU Danlin | 2015 | Journal of Arid Land2015，7，5： | 1 |
| 15 | Modified perpendicular drought index (MPDI): A real-time drought monitoring method显示文摘 | Ghulam Abduwasit Qin Qiming Teyip Tashpolat | 2007 | ISPRS Journal of Photogrammetry and Remote Sensing2007，62，2： | 1 |
| 16 | Analysis of Soil and Water Balance on the Land Arrangement Function显示文摘The natural supply of land resources is limited, but the economic supply may change along with social and economic development, and its size is decided bye nature and social and economic body conditions. When the supplying ability of land resources threatens the development of society and the conflict between people and land becomes tense, it forced people to im- prove land utilization and to increase the effective supply of land resources. The paper made an overall consideration on the characteristics of the irrigated farming and the frail ecological environment in Fuhai County, Altay Area, Xinjiang Uigur Autonomous Region and explored land arrangement planning as well as water resource planning and environmental protection. The paper evaluated natural resources, land utilization and water resource of the case study areas and focused on the spatio-temporal balance between the utilization of water and land resources. In the end the paper a feasible plan was made out for the land arrangement project. | Tashpolat Tiyip | 2007 | Chinese Journal of Population,Resources and Environment2007，5，2： | 0 |
| 17 | THE SEQUENCE OF PALEOENVIRONMENTAL CHANGES SINCE ABOUT 4KA B.P., RECORDED BY NIYA SECTION IN SOUTHERN MARGIN OF TARIM BASIN显示文摘Through synthetic researches of multi-index geological records of Niya section, which are of high resolution in southern margin of Tarim Basin, this paper has reconstructed the sequences of paleoclimate in this region during historical times (since about 4000a B.P.). During the last 4000 years, the area has experienced alternations of relative cold-moisture and relative warm-dry periods. Three evident cold-moisture periods and three warm-dry periods are identifing. The study shows that the human activities have an intimate relation with the evolution of paleoclimate in the southern Xinjiang. Paleoclimate has played very important role in influencing human being′s agricultural activities. | ZHONG Wei, XIONG Hei-gang, TASHPOLAT Tiyip, SHU Qiang (Department of Geography, Xinjiang University,Urumqi 830046, P.R. China) | 2001 | Chinese Geographical Science2001，11，2： | 0 |
| 18 | Relations between soil heterogeneity and common reed(Phragmites australis Trin.ex Steud.) colonization in the Keriya River Basin,Xinjiang of China显示文摘How common reed(Phragmites australis Trin. ex Steud.) colonization correlates to soil heterogeneity and environmental determinants remains unclear in arid areas. We conducted a field investigation and soil sampling in 100 plots along Keriya River Basin to uncover the relationship between common reed and heterogeneous soils. Reed colonization variables and its soil properties were measured and recorded for the analysis of their relationship using Pearson correlation and redundancy analysis methods. The comparison results of common reed characteristics among 100 plots showed that common reeds performed strong tolerance and ecophysiological plasticity to edaphic stresses. Common reed colonization was tightly connected to soil heterogeneity according to the correlation analysis between its colonization characteristics and soil properties. Common reed colonization got feedbacks on soil properties as well, including the increase of soil organic matter and the alleviation of salt uplifting. The main limiting environmental determinant of common reed colonization was soil salt, followed by pH and soil water content. | Lu GONG ChangJun LI Tashpolat TIYIP | 2014 | Journal of Arid Land2014，6，6： | 0 |
| 19 | Historical climate changes in southern Xinjiang显示文摘Based on the synthetic researches of multi-index geologic records of Niya section, which are of high resolution in southern margin of the Tarim Basin, together with other geologic records in southern Xinjiang, this paper has reconstructed the history of paleoclimatic changes in this region since about 4.00 ka BP. During the last 4.00 ka, the region of southern Xinjiang has experienced alternations of relative cold-wet and relative warm-dry periods. Three remarkable cold-wet periods (4.00-3.45 ka BP., 2.50-1.90 ka BP., ca.1.40-1.00 ka BP.) and three warm-dry periods (3.45-2.50 ka BP., 1.90-1.40 ka BP., 1.00 ka BP.-present) are identified. It is shown that human activities have an intimate relation with the evolution of paleoclimate in southern Xinjiang. | Zhong Wei Xiong Hei-gang Tashpolat Tiyip Hiroki Takmura Shu Qiang | 2001 | Journal of Geographical Sciences2001，11，4： | 0 |
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