A theory of atmospheric tides generated by the differential heating between land and sea     

F. B. A. Giwa  L. A. Hussain 《Pure and Applied Geophysics》1978,116(1):56-65

Summary The differential heating between land and sea is incorporated into the theory of atmospheric tides. This involves the representation of the land and sea distribution by a set of Fourier series.The theory postulates the existence of waves of angular speeds different from the angular velocity of the earth with some of the waves travelling from West to East instead of the usual East to West.By considering the diurnal variation of eddy diffusion of heat energy absorbed close to the surface, the semidiurnal standing waves at the poles was calculated by the application of this theory. The order of magnitude of the calculated tides agreed well with observation, though, contrary to observation, the calculated amplitude at the South pole is larger than that at the North pole.It is also shown that the polar standing oscillation is caused mainly by the land and sea distribution between 75°N and 45°S.  相似文献   

Palaeoclimate,stratigraphy and prehistory in north and west Rajasthan     

D. P. Agrawal  P. S. Datta  Zahid Hussain  R. V. Krishnamurthy  V. N. Misra  S. N. Rajaguru  P. K. Thomas 《Journal of Earth System Science》1980,89(1):51-66

Quaternary formations in western Rajasthan are of fluvial, locustrinal and aeolian origins. Fossil gravel ridge of Jayal in Nagaur District is one of the earliest quaternary formations so far recorded in the region. A rich lower palaeolithic habitation-cum-workshop site has been discovered in association with the gravel ridge. Multiple evidence for climatic change in the area during the quaternary period is discussed.  相似文献   

Age of Saurashtra miliolites by U-Th decay series methods: possible implications to their origin     

N Hussain  N Bhandari  K R Ramanathan  B L K Somayajulu 《Journal of Earth System Science》1980,89(2):276-276

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Germination and seedling growth of corn (Zea mays l.) under varying levels of copper and zinc     

S. Mahmood  A. Hussain  Z. Saeed  M. Athar 《International Journal of Environmental Science and Technology》2005,2(3):269-274

The heavy metal tolerance in corn (Zea mays L.) var. ‘Neelum’ was assessed at germination and seedling growth after having subjected it to different concentrations of CuSO₄ and ZnSO₄. Germination was not affected by any of the metal tested, whereas initial growth was strongly inhibited by increasing concentrations of ZnSO₄. Seedlings developed toxicity symptoms in the presence of both metals but more chlorotic and necrotic regions were observed at varying levels of ZnSO₄ than CuSO₄. The metal accumulation was concentration dependent. Z. mays seedlings accumulated more copper in roots but greater contents of zinc in their shoots. On the basis of results presented here, it can be concluded that the cultivar of the species tested has shown a marked sensitivity to the presence of small amounts of metals present in the growth medium. The data support the assumption that metal sensitivity is probably due to strong tendency of the species to accumulate them. This justifies that the corn variety ‘Neelum’ is not suitable for the cultivation under situations where water and soil suffer from occasional and/ or transitory metal pollution.  相似文献   

Genotypic and environmental interaction in advanced lines of rice under salt-affected soils of Punjab     

Y. Ali  G. Sarwar  Z. Aslam  F. Hussain 《International Journal of Environmental Science and Technology》2006,3(2):191-195

Sixteen genotypes developed through hybridization and mutation breeding techniques were evaluated during the year 2003–04 on nine locations covering most of the area of Punjab province including Faisalabad, Toba Tek Singh and Jhang. NIAB-IRRI-9, Jhona-379 salt tolerant genotypes and super Basmati, a salt sensitive variety were included as standard checks. The tested material (six genotypes) was generated by crossing fine varieties of rice viz. Basmati-370 and Basmati-385 with three coarse varieties of rice viz. NIAB-IRRI-9, Jhona-349 and NIAB-Rice-1. The mutants (seven mutants) were derived by gamma irradiation of rice varieties, Basmati-370 and Basmati-385. The nine sets of experiments were conducted in the naturally high saline sodic soils having EC range of 9.2–18.13 d/Sm pH=8.65–9.50, and SAR=20.7–37.15. The seed yield data collected at maturity and stability parameters were computed to know genotypic x environment interaction and varietals performance. The combined analysis of variance showed highly significant variance in case of varieties, locations and varieties x locations interaction. Varieties and varieties x Environment (Lin) also showed highly significant differences. It means that genotypes exhibited different behavior in different locations / environments which is due to their different genetic make up. The behavior may be cross over (in which significant change in ranking occurs from one environment to another) or cross over nature (in which case the ranking of genotype remains constant across environments and the interaction is significant because of change in the magnitude of response) depending upon the ranking order of genotypes performance under different environment. In our study, only super Basmati behavior was of almost non cross over nature, while others had cross over type of interaction. Based on overall mean seed performance, mutant NIAB-Rice-4 and DM-38/88 produced significantly the highest grain yield (5.6 t/ha) followed by mutant line NIAB-Rice-5 (5.4 t/ha) and NIAB-rice-2 (5.3 t/ha). The lowest performing genotype was super Basmati (3.0 t/ha). The coarse variety Jhona-349 produced (4.8 t/ha) grain yield. Mutant line DM-38/88 showed significant regression co-efficient differences from unity while mutant line NIAB-Rice-4 showed non significant difference of regression co-efficient from unity. Mutant line, NIAB-Rice-4 also showed non significant difference of standard deviation to regression co-efficient from zero. All the three parameters of stability i.e. overall mean seed yield, regression co-efficient and standard deviation to regression, provided clear evidence that mutant line NIAB-Rice-4 produced maximum stable yield compared to super Basmati.  相似文献   

Removal of organic matter from reservoir water: mechanisms underpinning surface chemistry of natural adsorbents     

S. Hussain  J. van Leeuwen  R. Aryal  B. Sarkar  C. W. K. Chow  S. Beecham 《International Journal of Environmental Science and Technology》2018,15(4):847-862

One of the key challenges in water treatment industry is the removal of organic compounds by cost-effective methods. This study evaluated the adsorptive removal of dissolved organic carbon (DOC) from reservoir water using fuller’s earth (FE) in comparison with natural (SQ) and modified quartz (MSQ) sands. The removal capacities of FE at different contact times, pH levels, adsorbent dosages and initial DOC concentrations were compared with both the quartz sands. The optimum DOC removals by FE and SQs were achieved at contact time of 60 and 30 min, pH level of 6 and 4, and at adsorbent dose of 1.5 g/150 mL and 10 g/100 mL, respectively. The adsorption capacity of FE (1.05 mg/g) was much higher compared to the MSQ (0.04 mg/g) and SQ (0.01 mg/g). Adsorption equilibrium data better fitted to the Freundlich model than to the Langmuir model, suggesting that adsorption occurred primarily through multilayer formation onto the surfaces of FE and SQ. The pseudo-second-order model described the uptake kinetics more effectively than the pseudo-first-order and intra-particle diffusion models, indicating that the mechanism was primarily governed by chemisorption. These observations were well supported by the physiochemical characteristics and charge behaviour of the adsorbents. In mass-transfer study, the results of liquid film diffusion model showed that the adsorption of DOC on FE was not controlled by film diffusion, but other mechanisms also played an essential role. This study demonstrates that FE is an effective adsorbent for the removal of DOC in surface water treatment.  相似文献   

Geochemical characteristics of mafic and ultramafic rocks from the Naga Hills Ophiolite,India:Implications for petrogenesis     

Ajoy Dey  M.Faruque Hussain  Mrigendra N.Barman 《地学前缘(英文版)》2018,9(2):517-529

The Naga Hills Ophiolite(NHO) represents one of the fragments of Tethyan oceanic crust in the Himalayan Orogenic system which is exposed in the Phek and Kiphire districts of Nagaland, India. The NHO is composed of partially serpentinized dunite, peridotite, gabbro, basalt, minor plagiogranite,diorite dyke and marine sediments. The basalts are mainly composed of fine grained plagioclase feldspar, clinopyroxene and orthopyroxene and show quenching and variolitic textures. The gabbros are characterized by medium to coarse grained plagioclase, orthopyroxene and clinopyroxene with ophitic to sub-ophitic textures. The ultramafic cumulates are represented by olivine, Cpx and Opx.Geochemically, the basalts and gabbros are sub-alkaline to alkaline and show tholeiitic features.The basalts are characterized by 44.1-45.6 wt.% of SiO_2 with 28-38 of Mg#, and the gabbros by38.7-43.7 wt.% of SiO_2, and 26-79 of Mg#. The ultramafic rocks are characterized by 37.4-52.2 wt.% of SiO_2, and 80-88 of Mg#. In multi-element diagrams(spidergrams) both basalts and gabbros show fractionated trends with strong negative anomalies of Zr. Nb. Sr and a gentle negative anomaly of P.However, the rare earth element(REE) plots of the basalts and gabbros show two distinct patterns. The first pattern, represented by light REE(LREE) depletion, suggests N-MORB features and can be interpreted as a signature of Paleo-Tethyan oceanic crust. The second pattern, represented by LREE enrichment with negligible negative Eu anomaly, conforms to E-MORB, and may be related to an arc tectonic setting. In V vs. Ti/1000, Cr vs. Y and AFM diagrams, the basalts and gabbros plot within Island Arc Tholeiite(IAT) and MORB fields suggesting both ridge and arc related settings. The ultramafic rocks exhibit two distinct patterns both in spidergrams and in REE plots. In the spidergram, one group displays highly enriched pattern, whereas the other group shows near flat pattern compared to primordial mantle. In the REE plot, one group displays steeper slopes [(La/Yb)N = 4.340-4.341], whereas the other displays moderate to flat slopes [(La/Yb)N = 0.97-1.67] and negative Eu-anomalies. Our study suggests that the ultramafic rocks represent two possible mantle sources(fertile and refractory).  相似文献   

Rainfall-induced landslide in the active frontal fold–thrust belt of Northwestern Himalaya,Jammu: dynamics inferred by geological evidences and Ground Penetrating Radar     

Yudhbir Singh  Ahsan Ul Haq  G. M. Bhat  S. K. Pandita  Arjun Singh  Rameshwar Sangra  Gulzar Hussain  S. S. Kotwal 《Environmental Earth Sciences》2018,77(16):592

Landslides are the most established geological hazards in the frontal fold–thrust belt of Northwestern Himalaya comprising of Siwaliks and Murree strata. The continuous rainfall from 2 to 6 September, 2014 caused a massive landslide at village Sadal in Udhampur district of Jammu and Kashmir state. The landslide occurred in the early morning of September 6, 2014, destroying entire Sadal habitation comprising 45 houses, and killing 41 people and more than 500 domestic animals. Google earth images of pre and post-landslide events along with the field measurements show the kinematics of upper and lower parts of the slide. Horizontal and vertical components of displacement and mode of failure suggest the landslide as of complex nature. The shallow subsurface geophysical imaging through Ground Penetrating Radar (GPR) survey shows the failure plane composed of friable mudstone bed underlain by massive mudstone and overlain by cross-bedded sandstone. The depth of debris material above the failure plane ranges from 6 m at Site S1a-b to 10 m at Site-S2b and 20 m at Site S3a. The velocity analysis of Site-3 shows four thick layers represented from bottom to surface by L1—sandstone (V?=?0.16 m/ns, travel time?=?356.36 ns), L2—mudstone (V?=?0.17 m/ns, travel time?=?288.48 ns), L3—massive mudstone (V?=?0.19 m/ns, travel time 220.68 ns), and L4—cross-laminated sandstone (V?=?0.20 m/ns, travel time?=?77.58 ns) overlaying the failure plane. The study shows the landslide occur along the western limb of a fold identified during the present work. We mapped an old landslide on the same limb which shows 5–6 m-thick subsurface debris material with thick rock fragments involved in the landslide process. The detailed geological and geophysical investigations suggest that both the landslides were triggered by extreme rain fall events.  相似文献   

Cadmium (Cd) concentration in wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis>) grown in Cd-spiked soil varies with the doses and biochar feedstock     

Muhammad Zia ur Rehman  Muhammad Rizwan  Shafaqat Ali  Muhammad Irfan Sohail  Amjad Hussain  Muhammad Farooq Qayyum  Hinnan Khalid  Muhammad Zeeshan  Naveeda Majid 《Arabian Journal of Geosciences》2018,11(21):685

Biochar is considered a promising amendment for the reduction of metal concentration in plants; however, the effects of biochar in terms of dose and feedstock on metal uptake by plants remain widely unclear. In the current study, three individual biochars were prepared at 450 °C from different feedstocks (wheat straw, sukh chain (Pongamia pinnata), and cotton sticks). The main aim was to evaluate their ability to remediate cadmium (Cd)-spiked soil in terms of growth response and Cd uptake by wheat (Triticum aestivum) tissues. Biochars were separately applied at 0, 1, and 2% (w/w) in Cd-spiked soil and wheat was grown until maturity in pots and then morphological and physiological parameters and Cd concentrations in grains, roots, and shoots were determined. The post-harvest soil was analyzed for extractable Cd concentrations. Plants grown in Cd-spiked soil treated with biochars had higher seed germination, lengths of roots, shoots, and spikes, grains per spike and leaf relative water contents, chlorophyll contents, and dry weight of roots, shoots, and grains as compared to the untreated control. Biochar treatments significantly decreased the Cd concentrations in shoots, roots, and grains as well as total Cd uptake by grains. Soil extractable Cd concentrations were significantly decreased with biochar treatments. The application of 2.0% wheat straw biochar was the most efficient treatment in increasing grain yield and decreasing Cd in grains as well as soil extractable Cd than the other two biochars and doses applied.  相似文献   

Siphonostomatoid copepods infecting Squalus acutipinnis Regan, 1908 off South Africa     

SM Dippenaar  RA Molele 《African Journal of Marine Science》2015,37(4):605-608

Squalus acutipinnis (previously included in S. megalops) individuals caught off the east, south and west coasts of South Africa were examined for siphonostomatoid copepod infection. Collected siphonostomatoids were fixed and preserved in 70% ethanol and studied under microscopes using both transmitted and incidental light. The copepods were identified and the host-parasite associations estimated by calculating their prevalence, mean intensity and mean abundance. The siphonostomatoids represented four families and six species, and included new host records for Nemesis sp., Lernaeopoda sp. and Eudactylina acanthii, and a new geographical record for E. acanthii. Squalus acutipinnis individuals were infected by relatively low loads of siphonostomatoids. The most commonly found species was Achtheinus pinguis, the only species found off all three coasts. There was no difference in the prevalence of A. pinguis in sharks sampled off the three coasts but the highest mean intensity was found on the East Coast followed by the West Coast. The overall prevalence of A. pinguis was 33.6%, and was an order of magnitude higher than that of the other siphonostomatoids recorded. At such low levels of infection it will thus be necessary to examine a large number of hosts to determine the biodiversity of siphonostomatoids and geographical differences in prevalence in South African waters.  相似文献