Impact of Southern Oscillation on the Frequency of Monsoon Depressions in the Bay of Bengal     

Singh  O. P.  Ali Khan  Tariq Masood  Rahman  Md. Sazedur 《Natural Hazards》2002,25(2):101-115

The impact of Southern Oscillation on thecyclogenesis over the Bay of Bengal duringthe summer monsoon has been investigated.The analysis of correlation coefficients(CCs) between the frequency of monsoondepressions and the Southern OscillationIndex (SOI) reveals that more depressionsform during July and August of El Niñoyears. Due to this, the seasonal frequencyof monsoon depressions remains little higherduring El Niño epochs even though thecorrelations for June and September are notsignificant. The CCs for July and August aresignificant at the 99% level.The El Niño-Southern Oscillation (ENSO)is known to affect Indian MonsoonRainfall (IMR) adversely. The enhancedcyclogenesis over the Bay of Bengal duringJuly and August is an impact of ENSO whichneeds to be examined closely. Increasedcyclogenesis over the Bay of Bengal may bereducing the deficiency in IMR duringEl Niño years by producing more rainfallover the eastern parts of India duringJuly and August. Thus there is a considerablespatial variation in the impact of ENSOon the monsoon rainfall over India and El Niñoneed not necessarily imply a monsoonfailure everywhere in India.The area of formation of monsoon depressionsshifts eastward during El Niño years.Warmer sea surface temperature (SST) anomaliesprevail over northwest and adjoiningwestcentral Bay of Bengal during premonsoon andmonsoon seasons of El Niño years.May minus March SOI can provide useful predictionsof monsoon depression frequencyduring July and August.  相似文献   

Limnology of four saline lakes in western Victoria, Australia: II. Biological parameters     

Tariq A. Khan   《Limnologica》2003,33(4):327-339

Major biological parameters of four permanent (Lake Colac, Modewarre, Bolac and Tooliorook), shallow and slightly saline lakes in the volcanic plains of western Victoria, Australia recorded bi-monthly between November 1999–September 2001 are described. Chlorophyll a concentration ranged from 3–29 μg l⁻¹ with peaks in autumn. Phytoplankton taxa recorded were diverse, with Chlorophyta and Bacillariophyta being common. Cyanobacterial blooms were recorded mostly in summer. Zooplankton abundance in the lakes ranged from 12–368 individuals per litre. Rotifera dominated Lake Bolac, Copepoda dominated Lake Modewarre and they co-dominated Lake Colac and Tooliorook. Zooplankton interactions with phytoplankton suggest that simple predator-prey relationships cannot fully explain the trends exhibited and that a more complex model was acting to regulate algal biomass. A decline in the abundance of zooplankton in summer in Lake Modewarre was attributed to predation by high number of exotic larval carp at that time of the year. A total of 25 benthic macroinvertebrate taxa were recorded from Lake Colac, 30 from Modewarre, 22 from Bolac and 35 from Tooliorook. Twenty-one of the 45 taxa identified occurred in at least three lakes. Nine of the 12 taxa that occurred in only one lake were from Lake Tooliorook. Simpson's diversity index was low in Lake Bolac when compared to other three lakes. Lake Modewarre had more benthic individuals (3246 Ind m⁻²) than other three lakes (range 624–1397 Ind m⁻²). The combined contribution of Ostracoda, Amphipoda and Gastropoda dominated the benthos in all the lakes throughout the study period. Macroinvertebrate taxa richness was higher in the present study lakes than recorded from the lakes in the region. Frequency of sampling and number of sampling sites seemed more important in determining species richness than the size and shallowness of the lakes.  相似文献   

Synthesis of biochar from sugarcane filter-cake and its impacts on physiological performance of lettuce (<Emphasis Type="Italic">Lettuce sativa</Emphasis>) grown on cadmium contaminated soil     

Anum Sehar  Rukhsanda Aziz  Muhammad Tariq Rafiq  Muhammad Mazhar Hussain  Muhammad Rizwan  Adiba Khan Sehrish  Muhammad Khalid Rafiq  Jalal ud Din  Qaiser Hussain  Mohammad I. Al-Wabel  Shafaqat Ali 《Arabian Journal of Geosciences》2018,11(20):634

Soil contamination with cadmium has become major concern all over the world because of its adverse impacts on ecosystem health and agricultural land. Soil amendment with biochar may have varied effects on physical and chemical properties of soil. The objective of the study was to explore the impact of sugarcane filter-cake biochar on physiological performance and growth of lettuce in an aged soil. Four different doses (0, 1.5%, 3%, and 5%) of biochar were used in the soil and conditioned for 1 month. After this, lettuce seedlings were grown in the soil. The results showed that the biochar treatment improved the fresh and dry biomass of leaves and roots as well as plant height while diminished the bioavailability of cadmium from the soil. As compared to control, biochar significantly enhanced the chlorophyll content in lettuce leaves. Due to the biochar amendment, the oxidative stress decreased in lettuce shoots over the control. As compared to control, concentration of cadmium in lettuce significantly decreased after the application of biochar. It was concluded that biochar could mitigate the toxicity of cadmium in lettuce by altering the biochemical and physiological processes in cadmium contaminated soil.  相似文献   

Identifying the determinants of access to agricultural credit in Southern Punjab of Pakistan     

Zulfiqar  Farah  Shang  Jie  Zada  Muhammad  Alam  Qamar  Rauf  Tariq 《GeoJournal》2021,86(6):2767-2776

Based on the survey data of 250 farmers from the Multan district of Southern region of Punjab, Pakistan this study aims to empirically examine the determinants of access to agricultural credit. This study used the probit model to analyze the data. The results revealed that formal education, farm size, level of farm mechanization, farm revenue and landholding size positively and significantly influenced access to agricultural credit while the age of the farmer’s, distance, and off- farm income negatively and insignificantly influenced farmer’s accessibility to agricultural credit. The findings of the current study offer a policy guideline to streamline national policy on agricultural finance. This study also recommends that ZaraiTaraqiati Bank (ZTBL) and other Commercial Banks should improve their agricultural credit schemes to fulfil the diversified needs of small farm holders.

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Missing basics: a study on sanitation and women’s health in urban slums in Lucknow,India     

Nagpal  Anushree  Hassan  Mohammad  Siddiqui  Masood Ahsan  Tajdar  Atiqua  Hashim  Mohammad  Singh  Abhra  Gaur  Suman 《GeoJournal》2021,86(2):649-661

GeoJournal - Sanitation is a multidimensional concept alluding primarily to provision of services for safe disposal of human excreta, provision of clean potable water as well as maintenance of...  相似文献   

Ring foundation on elastic subgrade: an analytical solution for computer modelling using the Lagrangian multiplier method          下载免费PDF全文

Shahin Nayyeri  Masood Hajali  Caesar Abi Shdid 《国际地质力学数值与分析法杂志》2016,40(14):2017-2030

In the practice of geotechnical engineering, the case of a ring footing carrying a set of concentrated point loads is a common problem. At times, the induced vertical and angular displacements for the ring footing need to be evaluated at a relatively precise level. By making use of the governing set of equations derived for the case of a general curved beam, expressions that can be easily implemented in modern computing software are derived for the vertical and angular displacements of a ring footing of rectangular cross section as functions of the radial position. The loading case considered is a vertical point load, and the soil is modelled as elastic. Estimates of the displacements have been shown for a common range of practical applications. The behaviour for a set of concentrated loads may be evaluated using the derived equations through direct superposition. Nonlinear finite element analysis is used to evaluate the vertical deflection and angular twist of the ring foundation. Numerical analysis performed for three ring foundations with different radii and cross sections is reported to validate the accuracy of the derived analytical solution. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

Awkward geographies: Spatializing academic responsibility, encountering Sri Lanka     

Tariq Jazeel 《Singapore journal of tropical geography》2007,28(3):287-299

This paper responds to recent postcolonial geographical scholarship that sets forth transformative agendas in order to create more cosmopolitan theoretical projects within the discipline. For many geographers the challenges they face are located within not only their own disciplinary parameters, but also those of other specific research communities within which their work situates them. By bringing geography and area studies into productive conversation, this paper explores the tensions between negotiating one's academic voice, position and responsibility within geography as well as within a specific area studies community. More specifically, as a UK-based geographer I reflect on some of my own fairly unremarkable, yet extremely awkward, encounters during the course of scholarly praxis in Sri Lanka in order to raise questions over the spatialities of responsibility and political engagement in such academic praxis. I seek to theorize the chasms that open in such awkward encounters between notionally situated 'local' and 'foreign' scholars respectively and, in particular, develop ways of engaging and reorienting those chasms in ways that might enable the production of theoretically rich, yet richly contextualized postcolonial knowledges committed to the site of one's scholarly praxis – not just to the advancement of a more cosmopolitan theoretical project within geography.  相似文献   

Dietary studies on exotic carp (<Emphasis Type="Italic">Cyprinus carpio</Emphasis> L.) from two lakes of western Victoria,Australia     

Tariq A. Khan 《Aquatic Sciences - Research Across Boundaries》2003,65(3):272-286

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Total mercury content in some marine fish from the Indian Ocean     

Tariq W. Kureishy  M. D. George  R. Sen Gupta 《Marine pollution bulletin》1979,10(12):357-360

Total mercury was estimated in liver, gonads and muscle of some of the marine fishes from the Indian Ocean. The highest mercury concentration was observed in the muscle of sharks while the total mercury concentration was practically non-detectable in the liver and gonads. The range of all the values was 0.09–0.21 ppm (wet weight basis) and is quite low to reflect any possible mercury contamination.  相似文献   

A study of aerosol properties over Lahore (Pakistan) by using AERONET data     

Muhammad Ali  Salman Tariq  Khalid Mahmood  Asim Daud  Adila Batool  Zia-ul-Haq 《Asia-Pacific Journal of Atmospheric Sciences》2014,50(2):153-162

It is well established that aerosols affect the climate in a variety of ways. In order to understand these effects, we require an insight into the properties of aerosols. In this paper we present a study of aerosol properties such as aerosol optical depth (AOD), single scattering albedo (SSA) and aerosol radiative forcing (ARF) over mega city of Lahore (Pakistan). The data from Aerosol Robotic Network (AERONET) have been used for the period December 2009 to October 2011. The seasonal average values of AOD, asymmetry parameter (ASY) and volume size distribution in coarse mode were observed to be highest in summer. On the other hand, the average values of Angstrom exponent (AE) and imaginary part of refractive index (RI) were found to be maximum in winter. The average value of real part of RI was found to be higher in spring than in all other seasons. The SSA exhibited an increasing trend with wavelength in the range 440 nm–1020 nm in spring, summer and fall indicating the dominance of coarse particles (usually dust). However, a decreasing trend was found in winter in the range 675 nm–1020 nm pointing towards the dominance of biomass and urban/industrial aerosols. As far as aerosol radiative forcing (ARF) is concerned, we have found that during the spring season ARF was lowest at the surface of Earth and highest at top of the atmosphere (TOA). This indicates that the atmosphere was warmer in spring than in all the remaining seasons.  相似文献