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Study of Sand Dunes and Their Effect on Desertification of Cultivated Lands in Shaanxi Province, china Using Remote Sensing Techniques

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Journal of china university of geosciences 2002年第3期13卷 234-239页

作者： mushtak talib jabbar Hu Guangdao Chen Jianguo faculty of earth resources, china university of geosciences, wuhan 430074 faculty of earth resources China University of Geosciences Wuhan 430074

About half of the arid and semi-arid lands in the world are deserts thatcomprise various types of aeolian sand dunes deposits. In Shaanxi Province, aeolian sand dunes coverconsiderable areas of the Yulin desert and northern Jinbian. Sand dunes are moving in the main winddirection and converting some agricultural area to wasteland. Remote sensing of sand dunes helps inthe understanding of aeolian process and desertification. Remote sensing data combined with fieldstudies are valuable in studying sand dunes, regional aeolian depositional history. In particular,active and inactive sand dunes of the north Shaanxi Province were studied using remote sensing andgeographic information system. In this study, we describe the Landsat thematic mapper (TM) images,covering north Shaanxi Province, which were used to study the distribution, shape, size, trends,density and movement of sand dunes and their effect on desertification of cultivated *** was made depending on soil erodibility factor (Ⅰ) and local climatic factor (C) duringthe period (June to September). The result indicates that soil erosion caused sand drift of 8.957 5,7. 03 ton for Yulin and Jinbian, respectively. The mean sand dunes movement rate were 4.37, 3.11 m,whereas, monthly sand dune advance rate were 1. 092 5, 0. 777 5m, for the two locations,respectively. The study reveals that cultivated lands extended obliquely to the direction of sanddune movement are extremely affected, while other segments that extend parallel to the direction ofthe movement are not affected. Accordingly the north Shaanxi Province was divided into areas ofdifferent classes of potential risk. Moreover, blown sands and sand movement from neighboringhighlands also affect the area of western desert.

关键词： sand dunes desertification remote sensing crust index china

Desertification Risk Monitoring for NorthShaanxi Province, china, Using NormalizedDifference Vegetation Index (NDVI)

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Journal of china university of geosciences 2002年第1期13卷 58-66,94页

作者： mushtak talib jabbarfaculty of earth resources , china university of geosciences , wuhan 430074 faculty of earth resources China University of Geosciences Wuhan 430074

In this study, the remote sensing is applied to the examination of the relationship between desertification and normalized difference vegetation index (NDVI) in the context of northern Shaanxi Province. This relationship is also examined using spatial analysis methods. A strong negative correlation is found in the largest area desert, indicating that the relationship between desert and NDVI is not a simple linear one and that the correlation coefficient between NDVI and vegetation abundance is significant. The normalized difference vegetation index (NDVI) was compared with other vegetation index-based methodologies. NDVI is a valuable first-cut indicator for such systems, although the analysis and interpretation of its relationship to desertification are complex and also based on the detailed analysis of its relationship to ecological zone, vegetation type and season. Conclusions thus made would help to upgrade the methodology as an effective tool for early-warning desertification in the northern Shaanxi Province where a drought is a recurring threat. This methodology includes the integration of NDVI with other socio-economic and bio-physical indicators in CIS, the complementation of desert area data with satellite data, and the analysis of the relationship between NDVI and specific climatic zones, for each season and vegetation type.

关键词： desert desertification remote sensing NDVI china.

Using Remote Sensing and GIS Techniques to Study Soil Degradation Processes in North Shaanxi Province,china

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Journal of china university of geosciences 2003年第4期14卷 356-362页

作者： mushtak talib jabbar faculty of earth resources China University of Geosciences

Satellite image data and thematic map data were used to provide comprehensive views of surface-bound conditions such as soil and vegetation degradation. The current work applies a computerized parametric methodology, developed by FAO, UNEP and UNESCO to assess and evaluate soil degradation at 1∶250 000 mapping scale. The study area is located in the arid and semi-arid zone of the northern part of Shaanxi Province in china, a region with considerable agricultural potential; Landsat TM images were utilized to provide recent data on land cover and use of the area. ARC/INFO and ArcView softwares were used to manage and manipulate thematic data, to process satellite images, and tabular data source. ER mapper software is utilized to derive the normalized difference vegetation index (ND VI) values while field data to estimate soil erodibility ( SE ) factor. A system is established for rating soil parameters, slope, climate factor and human factor activity. The rating values serve as inputs into a modified universal soil loss equation (USLE) to calculate the present state and risk for soil degradation processes, namely soil wind erosion. The produced maps and tabular data show the risk and the present status of different soil degradation processes. The study area, in general, is exposed to high risk of wind erosion and high hazards of water erosion. Several desertification maps were produced, which reflect the desertification types persisting in the study area. Wind erosion, water erosion, vegetation degradation, physical degradation and salinization are the basic desertification maps, and others are combinations of these basic maps. In terms of statistic analysis, 33.75 % of the total land area (120.330 0 ha) is considered as sand or sand dune, and not included in our analysis of desertification. About 29.41 % of the total land area has slight or moderate desertification and 37.465 % is facing severe desertification.

关键词： soil degradation desertification GIS remote sensing china.

Composition and source apportionment of dust fall around a natural lake

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Journal of Environmental Sciences 2015年第7期27卷 143-155页

作者： Mohd talib Latif Sofia Aida Ngah Doreena Dominick Intan Suraya Razak Xinxin Guo Thunwadee Srithawirat Idris Mushrifah School of Environmental and Natural Resource Sciences Faculty of Science and Technology Universiti Kebangsaan Malaysia Institute for Environment and Development (LESTARI) Universiti Kebangsaan Malaysia Centre for Atmospheric Chemistry University of Wollongong Department of Environmental Engineering Faculty of Engineering and Green Technology Universiti Tunku Abdul Rahman Department of Environmental Science Faculty of Science and Technology Pibulsongkram Rajabhat University Pusat Penyelidikan Tasik Chini (PPTC) Faculty of Science and Technology Universiti Kebangsaan Malaysia

The aim of this study was to determine the source apportionment of dust fall around Lake Chini, Malaysia. Samples were collected monthly between December 2012 and March2013 at seven sampling stations located around Lake Chini. The samples were filtered to separate the dissolved and undissolved solids. The ionic compositions（NO-3, SO2-4, Cl-and NH＋4） were determined using ion chromatography（IC） while major elements（K, Na, Ca and Mg） and trace metals（Zn, Fe, Al, Ni, Mn, Cr, Pb and Cd） were determined using inductively coupled plasma mass spectrometry（ICP-MS）. The results showed that the average concentration of total solids around Lake Chini was 93.49 ± 16.16 mg/（m2·day）. SO2-4, Na and Zn dominated the dissolved portion of the dust fall. The enrichment factors（EF） revealed that the source of the trace metals and major elements in the rain water was anthropogenic, except for Fe. Hierarchical agglomerative cluster analysis（HACA） classified the seven monitoring stations and 16 variables into five groups and three groups respectively. A coupled receptor model, principal component analysis multiple linear regression（PCA-MLR）, revealed that the sources of dust fall in Lake Chini were dominated by agricultural and biomass burning（42%）,followed by the earth＇s crust（28%）, sea spray（16%） and a mixture of soil dust and vehicle emissions（14%）.

关键词： Trace metal Major element Anion Source apportionment Lake Ghini Malaysia