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1.
Mushtak Talib Jabbar Faculty of Earth Resources China University of Geosciences Wuhan 《中国地质大学学报(英文版)》2001,12(2)
ＩＮＴＲＯＤＵＣＴＩＯＮＬａｒｇｅａｒｅａｓｏｆａｒｉｄａｎｄｓｅｍｉａｒｉｄｒｅｇｉｏｎｓｏｆｔｈｅｗｏｒｌｄａｒｅａｆ ｆｅｃｔｅｄｂｙｗｉｎｄｅｒｏｓｉｏｎ .Ａｐｐｒｏｘｉｍａｔｅｌｙ 2 8.4%ｏｆｔｈｉｓａｒｅａａｒｅａｆｆｅｃｔｅｄｂｙｓｅｖｅｒｅａｎｄｖｅｒｙｓｅｖｅｒｅｗｉｎｄｅｒｏｓｉｏｎ (Ｋａｔｅｓｅｔａｌ.,1977) .ＩｎＩｒａｑ ,ｔｈｅａｒｉｄａｎｄｓｅｍｉａｒｉｄｒｅｇｉｏｎｓｒｅｐｒｅｓｅｎｔｎｅａｒｌｙ 75%ｏｆｔｈｅｔｏｔａｌｌａｎｄ .5 0 %ｏｆｔｈｉｓｌａｎｄｉｓｓｕｂｊｅｃ… 相似文献
2.
Hadi Memarian Karim C. Abbaspour Jamal B. Talib Christopher Teh Boon Sung Alias Mohd Sood 《水文科学杂志》2013,58(10):1808-1829
AbstractThe Hulu Langat basin, a strategic watershed in Malaysia, has in recent decades been exposed to extensive changes in land-use and consequently hydrological conditions. In this work, the impact of Land Use and Cover Change (LUCC) on hydrological conditions (water discharge and sediment load) of the basin were investigated using the Soil and Water Assessment Tool (SWAT). Four land-use scenarios were defined for land-use change impact analysis, i.e. past, present (baseline), future and water conservation planning. The land-use maps, dated 1984, 1990, 1997 and 2002, were defined as the past scenarios for LUCC impact analysis. The present scenario was defined based on the 2006 land-use map. The 2020 land-use map was simulated using a cellular automata-Markov model and defined as the future scenario. Water conservation scenarios were produced based on guidelines published by Malaysia’s Department of Town and Country Planning and Department of Environment. Model calibration and uncertainty analysis was performed using the Sequential Uncertainty Fitting (SUFI-2) algorithm. The model robustness for water discharge simulation for the period 1997–2008 was good. However, due to uncertainties, mainly resulting from intense urban development in the basin, its robustness for sediment load simulation was only acceptable for the calibration period 1997–2004. The optimized model was run using different land-use maps over the periods 1997–2008 and 1997–2004 for water discharge and sediment load estimation, respectively. In comparison to the baseline scenario, SWAT simulation using the past and conservative scenarios showed significant reduction in monthly direct runoff and monthly sediment load, while SWAT simulation based on the future scenario showed significant increase in monthly direct runoff, monthly sediment load and groundwater recharge.
Editor D. Koutsoyiannis; Associate editor C. Perrin 相似文献
3.
A. Talib K. N. Gaur A. K. Sisodia Bilal A. Bhat Roohi Irshad 《Journal of the Geological Society of India》2012,80(5):667-675
A foraminiferal assemblage comprising 30 species dominated by the family Vaginulinidae is recovered from the Chari Formation exposed at Keera Dome, Kutch. The paper presents a systematic account of eight species, reported for the first time form the Indian region. Preliminary interpretations regarding age and palaeoenvironment are drawn on the basis of the recovered foraminiferal assemblage. The assemblage supports a Callovian to Oxfordian age for the studied sequence. A near shore, open marine environment ranging from mid to outer shelf is interpreted on the basis of the foraminiferal assemblage. 相似文献
4.
TheUBV photoelectric observation of the eclipsing binary star VV Ori were made at Al-Battani Observatory, Baghdad, Iraq, during nine nights in November and December, 1984 and January, 1985. As a result, three light curves were completed.An analysis of theB andV normal points light curves using the optimization method shows the existence of a slight shift in the primary mid-minimum epoch and the temperature of the secondary component is consistent with B5-type star. A new set of geometrical and physical elements is also presented. 相似文献
5.
Ahmad Norazhar Mohd YATIM Mohd Talib LATIF Fatimah AHAMAD Md Firoz KHAN Mohd Shahrul Mohd NADZIR Liew JUNENG 《大气科学进展》2019,36(12):1355-1370
This study investigates the recent extreme temperature trends across 19 stations in the Klang Valley, Malaysia, over the period 2006-16. Fourteen extreme index trends were analyzed using the Mann-Kendall non-parametric test, with Sen’s slope as a magnitude estimator. Generally, the annual daily mean temperature, daily mean maximum temperature, and daily mean minimum temperature in the Klang Valley increased significantly, by 0.07°C yr~(-1), 0.07°C yr~(-1)and 0.08°C yr~(-1),respectively. For the warm temperature indices, the results indicated a significant upward trend for the annual maximum of maximum temperature, by 0.09°C yr~(-1), and the annual maximum of minimum temperature, by 0.11°C yr~(-1). The results for the total number of warm days and warm nights showed significant increasing trends of 5.02 d yr~(-1)and 6.92 d yr~(-1),respectively. For the cold temperature indices, there were upward trends for the annual minimum of maximum temperature,by 0.09°C yr~(-1), and the annual minimum of minimum temperature, by 0.03°C yr~(-1), concurrent with the decreases in the total number cold days (TX10P), with-3.80 d yr~(-1), and cold nights (TN10P), with-4.33 d yr~(-1). The 34°C and 37°C summer days results showed significant upward trends of 4.10 d yr~(-1) and 0.25 d yr~(-1), respectively. Overall, these findings showed upward warming trends in the Klang Valley, with the minimum temperature rate increasing more than that of the maximum temperature, especially in urban areas. 相似文献
6.
MushtakTalibJabbar HUGuangdao ZHANGZhenfei 《地球空间信息科学学报》2004,7(3):187-192
The policy of the Chinese government concerning the horizontal expansion of the cultivated land through the reclamation of desert soils result in a total increase of 665. 985 km^2 during the period 1987-1999 in North Shaanxi. This increase is less than the loss in arable land by urbanization. The accelerated rate of change in agricultural areas calls for more rapid surveys of urbanization and loss of arable land. Remote sensing has a number of advantages over ground-based methods for such surveys. The multi-scale concept of remote sensing data help us study the problem in four towns. Several maps were produced to analyze the situation of urban coverage in different times. The evaluation of the status, rate and risk of urbanization are based on an accepted average of urban increase as 2% of population growth per year. 相似文献
7.
Mohsin Muhammad Mu Yongtong Memon Aamir Mahmood Kalhoro Muhammad Talib Shah Syed Baber Hussain 《中国海洋湖沼学报》2017,35(4):936-946
Pakistani marine waters are under an open access regime.Due to poor management and policy implications,blind fishing is continued which may result in ecological as well as economic losses.Thus,it is of utmost importance to estimate fishery resources before harvesting.In this study,catch and effort data,1996-2009,of Kiddi shrimp Parapenaeopsis stylifera fishery from Pakistani marine waters was analyzed by using specialized fishery software in order to know fishery stock status of this commercially important shrimp.Maximum,minimum and average capture production of P.stylifera was observed as 15 912 metric tons(mt)(1997),9 438 mt(2009) and 11 667 mt/a.Two stock assessment tools viz.CEDA(catch and effort data analysis) and ASPIC(a stock production model incorporating covariates) were used to compute MSY(maximum sustainable yield) of this organism.In CEDA,three surplus production models,Fox,Schaefer and Pella-Tomlinson,along with three error assumptions,log,log normal and gamma,were used.For initial proportion(IP) 0.8,the Fox model computed MSY as 6 858 mt(CV=0.204,R~2=0.709) and 7 384 mt(CV=0.149,R~2=0.72) for log and log normal error assumption respectively.Here,gamma error produced minimization failure.Estimated MSY by using Schaefer and Pella-Tomlinson models remained the same for log,log normal and gamma error assumptions i.e.7 083 mt,8 209 mt and 7 242 mt correspondingly.The Schafer results showed highest goodness of fit R~2(0.712) values.ASPIC computed MSY,CV,R~2,F_(MSY)and B_(MSY) parameters for the Fox model as 7 219 mt,0.142,0.872,0.111 and 65 280,while for the Logistic model the computed values remained 7 720 mt,0.148,0.868,0.107 and 72 110 correspondingly.Results obtained have shown that P.stylifera has been overexploited.Immediate steps are needed to conserve this fishery resource for the future and research on other species of commercial importance is urgently needed. 相似文献
8.
MushtakTalibJabbar 《中国地质大学学报(英文版)》2003,14(4):356-362
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 Arc-View 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. 相似文献
9.
About half of the arid and semi-arid lands in the world are deserts that comprise various types of aeolian sand dunes deposits. In Shaanxi Province, aeolian sand dunes cover considerable areas of the Yulin desert and northern Jinbian. Sand dunes are moving in the main wind direction and converting some agricultural area to wasteland. Remote sensing of sand dunes helps in the understanding of aeolian process and desertification. Remote sensing data combined with field studies 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 and geographic 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 lands. Estimation was made depending on soil erodibility factor (Ⅰ) and local climatic factor (C) during the 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 5 m, for the two locations, respectively. The study reveals that cultivated lands extended obliquely to the direction of sand dune movement are extremely affected, while other segments that extend parallel to the direction of the movement are not affected. Accordingly the north Shaanxi Province was divided into areas of different classes of potential risk. Moreover, blown sands and sand movement from neighboring highlands also affect the area of western desert. 相似文献
10.
MushtakTalibJabbar 《中国地质大学学报(英文版)》2002,13(1):58-66,94
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 sim-ple 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 inter-pretation of its relationship to desertification are complex and also based on the detailed analysis of its re-lationship 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 GIS ,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. 相似文献