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61.
M. Hassan M. A. Haq M. Aslam M. Saleem K. P. Akhtar S. Sarwar Alam 《International Journal of Environmental Science and Technology》2006,2(4):319-325
Twenty four new strains were tested for their yield, quality and Leaf Curl Virus (ClCuV) resistance. NIAB-111/S, NIAB-98 and NIAB-999 were significantly high fruit bearing varieties at 90 days completing 59.54, 48.26 and 46.00% fruiting respectively. Seed cotton yield of VH-142 was highest with 5417 kgha?1 and 52 per plant boll bearing, DNH-57 and NIAB-999 remained second and third with 5234 and 5095 kg ha?1 seed cotton yield, respectively. BH-160 and CRIS-467 were found to be second and third highest boll bearing varieties with 50.97 and 40.20 per plant average bolls respectively. Plant height in CRIS-467, MNH-642 and SLH-224 was significantly higher in comparison to other varieties.NIAB-98, CIM-499 and CIM-506 were found short stature varieties in comparison with other but out of these NIAB-98 and CIM-506 were in high yielding position and CIM-499 was found medium yielder variety. GOT% of MNH-642 remained highest having value of 45.00%. While GOT%. of NIBGE-1, CRIS-168 and CRIS-467 was at lowest position with 35.73, 35.89 and 36.62% respectively. NIAB-111, CIM-499 and BH-160 were at first position in terms of fibre fineness with micronaire values 3.98, 4.00 and 4.07 ìg/inch having fibre length 28.53, 31.38 and 30.23 mm respectively. Out of 26 varieties, 16 varieties resulted maturity index in the range of 85.03% and 90.30% with highest maturity index in case of NIBGE-1 (i.e. 90.30%) followed by NIAB-999 and MNH-642 with 89.55 and 85.5% respectively.CRIS-168, CRIS-468 and CRIS-467 were found viral susceptible. 相似文献
62.
The relationship among environmental variables,jellyfish and non‐gelatinous zooplankton: A case study in the north of the Gulf of Oman 下载免费PDF全文
Fatemeh Pourjomeh Mohammad Reza Shokri Hamid Rezai Hassan Rajabi‐Maham Elham Maghsoudlou 《Marine Ecology》2017,38(6)
Processes underlying the temporal and spatial variations observed in the distribution of jellyfish and non‐gelatinous zooplankton in the Gulf of Oman are not well understood. This information gap is clearly a major issue in controlling the harmful blooms of jellyfish and non‐gelatinous zooplankton. Samples of jellyfish and non‐gelatinous zooplankton were collected from six stations in Chabahar Bay and three stations in Pozm Bay within four seasons. At each station, environmental variables were also recorded from bottom and surface water. A total of 83 individuals of medusae representing four species of Scyphozoa (i.e., Cyanea nozakii, Chrysaora sp., Pelagia noctiluca, Catostylus tagi) and species of Hydrozoa (i.e., Diphyes sp., Rhacostoma sp., Aequorea spp.) were observed in the study area. A total of 70,727.25 individuals/m?3 of non‐gelatinous zooplankton dominated by copepods and cladocerans were collected in nine stations within the four seasons. The results of a RELATE analysis yielded no significant association between species composition for jellyfish and non‐gelatinous zooplankton. Among environmental variables, water transparency, nitrite concentration, water depth and temperature were better associated with the total variation in jellyfish species composition than with that of non‐gelatinous zooplankton. Dissolved oxygen, pH, and phosphate concentration were significant environmental variables associated with the variation in the spatial and temporal distribution patterns of non‐gelatinous zooplankton assemblages. Although some jellyfish species (i.e., Rhacostoma sp., Pelagia noctiluca, Catostylus tagi) occur independently of non‐gelatinous zooplankton assemblages, other jellyfish (i.e., Chrysaora sp., Aequorea spp., Cyanea nozakii, Diphyes sp.) are strongly correlated with non‐gelatinous zooplankton assemblages. 相似文献
63.
David A. Reid Marwan A. Hassan Stephen Bird Robin Pike Peter Tschaplinski 《地球表面变化过程与地形》2020,45(2):295-311
Stream channel morphology forms the template upon which hydraulic aspects of aquatic habitat are created, yet spatial and temporal variability in habitat imposed by changing morphology is not well understood. This paper presents a conceptual model linking sediment supply patterns to spatial and temporal variability in channel form and aquatic habitat. To evaluate this model, change over time in three habitat variables is quantified using a 2D hydrodynamic modeling approach. A 45-year record of topographic data from Carnation Creek, a catchment in coastal British Columbia, is used for the flow modeling. Using the Nays2DH modeling platform, water depths and velocities are simulated in eight channel segments located at different positions relative to locations of historical colluvial input using seven flow levels ranging from 3% to 400% of mean annual discharge (0.02 to 3.31 m s ). Results indicate that habitat availability changes through time as a result of sediment supply-driven changes to channel morphology and wood loads, but patterns in habitat vary as a function of dominant channel segment morphology. Spatial and temporal variability in morphology also influences the relationship between habitat availability and river discharge, leading to non-stationary habitat-discharge rating curves. When habitat areas are predicted by applying these curves to daily flow series spanning annual dry seasons, over 50% of the variance in cumulative seasonal habitat area can be explained by year-to-year changes in channel morphology and wood loading, indicating that changing morphology is an important factor for driving temporal habitat variability. This variance is related to the morphological variability of a channel segment, which in turn is associated with the segment position relative to zones of colluvial input. Collectively, these results suggest that variability in habitat is impacted by channel morphology, and can be evaluated partly on the basis of a channel's sediment supply regime. © 2019 John Wiley & Sons, Ltd. 相似文献
64.
Origin of peraluminous granites and granodiorites, Iberian massif, Spain: an experimental test of granite petrogenesis 总被引:27,自引:0,他引:27
Antonio Castro Alberto E. Patiño Douce L. Guillermo Corretgé Jesús D. de la Rosa Mohammed El-Biad Hassan El-Hmidi 《Contributions to Mineralogy and Petrology》1999,135(2-3):255-276
The discrimination between potential source materials involved in the genesis of Iberian granites and granodiorites, as well
as the role of mantle-crust interactions, are examined using constraints imposed by melting experiments, melting-assimilation
experiments and Sr-Nd isotope systematics. The Sr-Nd isotope relationships indicate the existence of different genetic trends
in which juvenile mantle materials are involved by different mechanisms: (1) a source trend, traced by a particular evolution
of the pre-Hercynian basement and indicating mantle participation at the time of sedimentation; (2) a set of magmatic trends
traced by gabbro-tonalite-enclave-granodiorite associations, implying the incorporation of new mantle material at the time
of granite generation. These relationships strongly support a pure crustal origin for the peraluminous leucogranites, derived
from partial melting of crustal protoliths, and a hybrid origin for the peraluminous granodiorites. These granodiorites are
the most abundant granitic rocks of the Central Iberian zone (CIZ) of the Iberian massif, implying that processes of hybridisation
by assimilation and/or magma mixing played an important role in granitoid production during the Hercynian orogeny. These hypotheses
have been tested by means of melting and assimilation experiments. Melting experiments in the range 800–900 °C and at pressures
of 3, 6, 10 and 15 kbar indicate that: (1) several potential source materials such as Bt-Ms gneisses and metagreywackes are
suitable for the production of peraluminous leucogranite melts; (2) the melt compositions are always leucogranitic, regardless
of pressure; (3) pressure exerts a strong influence on the fertility of the source: experiments at 3 kbar produce more than
20 vol% of melt, compared with less than 5 vol% of melt produced at 10 and 15 kbar and at the same temperature. The melting-assimilation
experiments carried out at 1000 °C and 4, 7 and 10 kbar and using a proportion of 50% gabbro and 50% gneiss give high melt
proportions (more than 50 vol.%) and noritic residues. These melts have the composition of leucogranodiorites, and overlap
with part of the compositional range of peraluminous granodiorites of the Iberian massif. The generation of more mafic granodiorites
may be explained by the incorporation of some residual orthopyroxene to the granodiorite magmas. The low solubility of Fe + Mg
prevents the generation of granodiorite melts with more than 3 wt% of MgO + FeO at all crustal pressures. The large volumes
of peraluminous, hybrid granodiorites, produced by assimilation of crustal rocks by mantle magmas, imply that an important
episode of crustal growth took place during the Late-Palaeozoic Hercynian orogeny in the Iberian massif.
Received: 30 June 1998 / Accepted: 27 November 1998 相似文献
65.
Analysis of symbiotic Symbiodinium in scleractinian corals off Northwestern Kish Island,Persian Gulf 下载免费PDF全文
Amirhossein Gheitanchi Mashini Mona Fard Yazdani Pargol Ghavam Mostafavi Mohammad Hassan Shahhosseiny 《Marine Ecology》2017,38(2)
The genus Symbiodinium plays an essential role in the resistance and survival of reef‐building corals during temperature anomalies. Coral colonies inhabiting the Persian Gulf (PG) experience extended periods of different stresses. Kish Island is located in the harsh environment of the Northern PG with previously reported bleaching episodes. Samples of six coral species from Northwestern Kish Island were analysed by internal transcribed spacer 2 of ribosomal DNA to identify in hospite Symbiodinium populations. The results showed that lineage D of Symbiodinium was the most prevalent clade among different coral colonies, while clade C was only detected in symbiosis with a single coral species. However, the detected Symbiodinium subclades belonged to two host generalists. The predominance of the stress tolerant Symbiodinium trenchii and subclade C3 could suggest an acclimatization strategy to cope with the hostile environment of the PG. 相似文献
66.
Ship-generated waves and return currents are capable of re-suspending significant quantities of bottom and bank sediments.However,most of the previous studies done on the subject do not show how and where sediment is re-suspended by the wakes and the directions of net transport.In this paper,a 3D numerical model based on hydro-sedimentary coupling is presented to search the relationship between the sediment movement,and the pattern of ship-generated waves around and far away from the vessel and the return currents around the ships.The hydrodynamic model is based on 3D Navier-Stokes equations including the standard k-ε model for turbulence processes,and the sediment transport model is based on a 3D equation for the re-suspended sediment transport.The computation results show that the areas of sediment concentration and transport(whether by resuspension or by the bedload) depend mainly on the position,the speed of the ship in the waterways,the kinematics of ship-generated waves and on the return flows.Thus,a map of sediment distribution and the modes of sediment transport generated by the passage of the ship are presented. 相似文献
67.
Reza Jamshidi Chenari Hassan Kamyab Farahbakhsh 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2015,9(2):96-108
This paper emphasises the true realisation of Cone Penetration Test (CPT) profiles considering non-stationary nature of the data. Formulation of stationary random field theory has been modified and adapted to non-stationary state in order to take into account the mean and variance variability for soil properties. Multi-variance correlation matrix along with the Cholesky decomposition technique was employed to produce realisations of non-homogenous and non-stationary random fields of CPT profiles. A piecewise and segmental data realisation according to the lithology and site class specifications acquired directly from CPT data is adopted in this study so as to render an accurate data simulation. For validation of proposed method 8 CPT test profiles collected from Urmia Lake site have been introduced and simulated by the stationary and non-stationary algorithms. The mean correlation coefficient between the actual CPT data profiles and related realisations along with some other important statistical parameters and their coefficients of variation strongly demonstrate that non-stationary random field generation technique gives quite better accuracy, by comparison to the conventional stationary random field generation scheme. 相似文献
68.
MERVATSAIDHASSAN SAYEDMAHMOUDSALEM 《中国地球化学学报》2001,20(2):120-129
Clay minerals from different Cretaceous stratigraphic successions of Egypt were investigated using XRD,DTA,dissolution analysis(DCB),IR,Moessbauer and X-ray Electron Spin Resonance(ESR) spectroscopes.The purity of the samples and the degree of their structural order were determined by XRD.The location of Fe in the octahedral sheet is characterized by absorption bands at-875cm^-1 assigned as Al-OH-Fe which persist after chemical dissolution of free iron.The Moessbauer spectra of these clays show two doublets with isomer shift and quadrupole splitting typical of octahedrally coordinated Fe^3 ,in addition to third doublet with hyperfine parameter typical of Fe^2 in the spectra of Abu-Had kaolinite (H) sample.Six-lines magnetic hyperfine components which are consistent with those of hematite are confirmed in the spectra of both Isel and Rish kaolinite samples.Goethite was confirmed by both IR and DTA.Multiple nature of ESR of these clays suggested structural Fe in distorted octahedral symmetry as well as non-structural Fe.Little dispersion and low swelling indices as well as incomplete activation of the investigated montmorillonite samplas by NaCO3 appear to be due to incomplete disaggregation of montmorillonite particles.This can be explained by the ability of Fe-gel to aggregate the montmorillonite into pseudo-particles and retard the rigid-gel structure.However,extraction of this ferric amorphous compound by dithonite treatment recovers the surface properties of the montmorillonite samples.On the other hand,the amount and site occupation of Fe associated with kaolinite samples show an inverse correlation with the parameters used to describe the degree of crystallinity perfection,color,brightness and vitrification range of these kaolinite samples. 相似文献
69.
In this study, a methodology for clustering 18 lakes in Alberta, Canada using the data of 19 water quality parameters for a period of 11 years (1988–2002) is presented. The methods consist of (i) principal component analysis (PCA) to determine the dominant water quality parameters, (ii) cluster analysis techniques to develop the characteristics of the clusters, and (iii) pattern‐match lakes to determine the appropriate cluster for each of the lakes. The PCA revealed that three principal components (PCs) were able to explain ~88% of the variability and the dominant water quality parameters were total dissolved solids, total phosphorus, and chlorophyll‐a. We obtained five clusters for the period 1994–1997 by using the dominant parameters with water quality deteriorating as the cluster number increased from 1 to 5. Upon matching cluster patterns with the entire dataset, it was observed that some of the lakes belonged to the same cluster all the time (e.g., cluster 1 for lakes Elkwater, Gregg, and Jarvis; cluster 3 for Sturgeon; cluster 4 for Moonshine; and cluster 5 for Saskatoon), while others changed with time. This methodology could be applied in other regions of the world to identify the most suitable source waters and prioritize their management. It could be helpful to analyze the natural controlling processes, pollution types, impact of seasonal changes and overall quality of source waters. This methodology could be used for monitoring water bodies in a cost effective and efficient way by sampling only less number of dominant parameters instead of using a large set of parameters. 相似文献
70.
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