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991.
Karim Nassar Hassan Fath Wael Elham Mahmod Ali Masria Kazuo Nadaoka Abdelazim Negm 《Journal of Coastal Conservation》2018,22(6):1057-1083
This paper introduces an appropriate visualization of how to effectively digitize, quantify and predict shoreline kinematics changes. The method relies mainly on the coupling of Geographic Information System (GIS) with Digital Shoreline Analysis System (DSAS). The North Sinai coast in Egypt is selected as a case study. The proposed technique is applied over a quarter-centennial period of 27 years (1989–2016). However, the years 2025, 2035, and 2050 are used for prediction purpose. Histogram threshold of band 5, Histogram threshold of band ratio, and Tasselled Cap Transformation (TCT) are initially tempted as semi-automatic shoreline extraction techniques for Landsat ETM 2010 imagery. Among of them, the TCT is found superior as a digitizing technique that attains the least normalized root mean square errors with the corresponding field data in 2010. Meanwhile, the shoreline change rates in the form of erosion/accretion patterns are automatically quantified by four statistical parameters functioned in DSAS coding. Those, namely end point rate (EPR), net shoreline movement (NSM), linear regression rate (LRR), and least median of squares (LMS). On the basis of the LRR and EPR results, this study offers to the coastal managers a highly reliable decision-support-algorism that can dynamically assist in elaborating strategies to curtail the non-affirmative consequences due to the erosion/accretion of the shoreline. 相似文献
992.
Introduction Nitromusksarewidelyusedassyntheticfragranceingredientsinformulationofsoaps,laundrydetergents,lotions,andbody careproducts,andsoon.Thecommercial anddomesticuseanddischargeofthesecompoundsfrommunicipalsewagesystemshaveledtotheirubiquitousoccurr… 相似文献
993.
Pillay AE Williams JR El Mardi MO Hassan SM Al-Hamdi A 《Environment international》2002,28(4):273-276
The study demonstrated that the mature dates we investigated were considered safe for human consumption. However, our findings revealed that much of the early fruit and leaves, which appeared at the advent of the fruiting season, possessed elevated levels of cadmium (Cd) that could accumulate in the food chain and thus impact adversely on the environment. In addition, animal feed for livestock contains date leaves, which should be restricted to the mature ones. The monitoring of cadmium in date palms is of considerable interest to environmental science and the thrust of this work, therefore, involved measurement, by ICP, of Cd in dates and corresponding leaf specimens, and evaluation of its distribution during the developmental stages of the fruiting season. Thirty-six date samples and 36 leaf specimens of the Fard cultivar were collected from "on" and "off" date palms during the Kimri, Bisir and Rutab stages of the fruiting season and subjected to suitable digestion procedures. Sample masses of typically 1 g (dry weight) were prepared in 25 ml dilute acid solution and investigated for trace levels of Cd by ICP-AES. Special attention was paid to contamination and the validation of our methodology. The Cd "threshold" in our study was 50 ng/g, in keeping with the levels of tolerance appearing in the literature. For the dates we found elevated levels of Cd [> 50 ng/g] in most of the samples, for both categories of "on" and "off" trees, during the Kimri stage. In the case of the leaves, the "on" samples revealed significant values up to 125 ng/g in Bisir, in some cases, but the trend for the "off" trees remained the same with the highest levels [> 100 ng/g] recorded during Kimri. Safe levels were attained during Rutab for all specimens. The possibility of a connection between Cd toxicity and the alternate-bearing phenomenon is discussed and this could be the subject of future interest. 相似文献
994.
The distribution of heavy metals viz., Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the water, sediments, plants and fish samples collected from the Kali Nadi (India) have been determined. The studies have shown that there was considerable variation in the concentration of heavy metals from one sampling station to the other which may be due to the variation in the quality of industrial and sewage wastes being added to the river at different places. The orders of the concentration of heavy metals in water, sediments, plants (Eicchornia crassipes) and fish (Heteropnuestes fossilis) were Fe > Zn > Cu > Mn > Cr > Ni > Pb > Co > Cd; Fe > Zn > Mn > Ni > Cr > Co > Cu > Pb > Cd; Fe > Mn > Zn > Cu > Ni > Co > Pb > Cr > Cd and Fe > Zn > Mn > Ni > Pb > Co > Cr > Cu > Cd, respectively. 相似文献
995.
A A Hassan S M el-Sewedy Y Minatogawa R Kido 《Journal of environmental science and health. Part. B》1991,26(3):333-338
Total and holo-enzyme activities of tryptophan 2,3-dioxygenase were measured in vitro in the presence and absence of the organophosphorous insecticide, dimethoate. Addition of dimethoate to the reaction mixture decreased the activities of both total and holo-forms. Total and holo-enzyme activities were decreased by 34% and 26%, respectively, by 1 mM dimethoate. On the other hand, 5 mM dimethoate resulted in 56% and 34% inhibition to total and holo-enzyme activities, respectively. Lineweaver-Burk plot of the total-enzyme activity at different tryptophan concentration in the presence of 2 mM dimethoate gave uncompetitive type of inhibition. 相似文献
996.
The severe drought of 1973–1975 in Somalia had major impacts on pastoral populations, many of whom moved into specially established camps where food, water and medical assistance were provided by the government and international agencies. At the end of the drought it was decided to settle the remaining 120,000 people in six settlements, three of which were agricultural and three oriented towards fishing. This paper analyzes these settlements, with particular attention paid to agricultural systems, organization and socioeconomic characteristics. Some of the problems facing the settlements included their location, administrative structure and relative overemphasis on social services as opposed to development of production and income generating activities. It is shown that the socioeconomic viability of settlements would be enhanced if careful studies were undertaken beforehand and if a diversified development strategy were employed. 相似文献
997.
E. S. Hassan 《Marine Biology》1993,116(3):489-495
Fourteen sampling sites distributed along the Abu Dhabi coast were surveyed monthly from October 1989 until September 1990 (except for the months February and April 1990), and a microbiological assessment was made. The saprophytic bacteria, salt tolerant saprophytic bacteria, Gram-negative bacteria, total and faecal coliforms were determined. In general, the numbers of all determined bacterial groups were found to be correlated with each other and in most cases they fluctuated together. Furthermore, the bacterial flora of the coastal water is markedly affected by water temperature, sampling sites and sampling time. The bacterial content of most sites fluctuated maximally during August and September (late summer). The natural self-purification process of coastal water samples was clearly observed. The predominant saprophytic bacterial genera and the common coliform species which occurred in the study area were identified. 相似文献
998.
Maeva Judith Orliac Pierre-Olivier Antoine Grégoire Métais Laurent Marivaux Jean-Yves Crochet Jean-Loup Welcomme Syed Rafiqul Hassan Baqri Ghazala Roohi 《Die Naturwissenschaften》2009,96(8):911-920
New dental remains of listriodont suids are described from the lower member of the early to middle Miocene Vihowa Formation
of the Bugti Hills, Pakistan. The material is homogeneous in terms of morphology and dimensions and referred as a whole to
Listriodon guptai Pilgrim, 1926. This species is also mentioned in coeval deposits of the Zinda Pir Dome, Pakistan, dating back to ca. 19 Ma.
The early occurrence of an advanced listriodont in Pakistan constrains the age of acquisition of several characters correlated
to lophodonty within Listriodontini, and raises major questions about the early history of the Old World Listriodontinae.
Strong morphological similarity between Listriodon guptai and the African species Listriodon akatikubas found in the late early Miocene of Maboko (Kenya, ca. 16.5 Ma) suggests that this latter is most probably a migrant originating
from Asia. 相似文献
999.
Mitigation of climate change impacts on maize productivity in northeast of Iran: a simulation study 总被引:1,自引:0,他引:1
Azam Lashkari Amin Alizadeh Ehsan Eyshi Rezaei Mohammad Bannayan 《Mitigation and Adaptation Strategies for Global Change》2012,17(1):1-16
Development and evaluation of mitigation strategies are fundamental to manage climate change risks. This study was built on
(1) quantifying the response of maize (Zea mays L.) grain yield to potential impacts of climate change and (2) investigating the effectiveness of changing sowing date of
maize as a mitigation option for Khorasan Province which is located in northeast of Iran. Two types of General Circulation
Models (GCM: (United Kingdom Met Office Hadley Center :HadCM3) and (Institute Pierre Simon Laplace: IPCM4)) and three scenarios
(A1B, A2 and B1) at four locations (Mashhad, Birjand, Bojnourd and Sabzevar) employed in this study. Long Ashton Research
Station-Weather Generator (LARS-WG) was employed for generating the future climate. The Cropping System Model (CSM)-CERES-Maize
was used for crop growth simulation under projected climate conditions. The results showed the simulated grain yields of maize
gradually would decrease (from −1% to −39%) during future 100 years compared to baseline under different scenarios and two
GCM at all study locations. The simulation results suggested that delayed sowing date from May to June at all study locations,
except Sabzevar location is the most effective mitigation option for avoiding thermal stress at end of growth period. In addition,
shifting in sowing date to March or April will be beneficial in terms of obtaining higher yields in Sabzevar. Grain yield
did not show special trend from north to south of Khorasan Province in the future climate. In general, change of sowing date
may be quite beneficial to mitigate climate change impacts on grain yield of maize in northeast of Iran. 相似文献
1000.
Syed Ali-Musstjab-Akber-Shah Eqani Riffat Naseem Malik Ashiq Mohammad 《Environmental geochemistry and health》2011,33(1):33-47
Organochlorine pesticides (OCPs), viz. β-hexachlorocyclohexane (β-HCH), γ-HCH, aldrin, dieldrin, endrin, heptachlor, endosulfan-I,
endosulfan-II, heptachlor endoepoxide, heptachlor exoepoxide, mirex, dicofol, o,p′-dichlorodiphenyltrichloroethane (o,p′-DDT), p,p′-dichlorodiphenyltrichloroethane (p,p′-DDT), dichlorodiphenyldichloroethane (DDD), and dichlorodiphenyltrichloroethylene (DDE) and 12 other physicochemical parameters
were measured in surface sediments from River Chenab during two sampling seasons (summer and winter, 2007) to evaluate spatial
and temporal trends of sediment pollution. Hierarchical agglomerative cluster analysis identified three groups of sites based
on spatial similarities in physicochemical parameters and OCP residual concentrations. Spatial discriminant function analysis
(DFA) segregated 14 parameters, viz. dicofol, endosulfan-I, heptachlor endoepoxide, dieldrin, DDD, DDE, endosulfan-II, o,p′-DDT, p,p′-DDT, pH, electrical conductivity (EC), Cl−1, total P (%), and silt, which explained 96% of total variance between spatial groups. γ-HCH was the most frequently detected
(63%) pesticide, followed by DDD (56%). The ratio of DDTs to their metabolites indicated current input and anaerobic biodegradation.
Temporal DFA highlighted aldrin, heptachlor endoepoxide, Cl−1, total P, and EC as important variables which caused variations between summer and winter. DDTs were relatively more prevalent
as compared to other OCPs in the sediments samples during both seasons. DDT metabolites were detected at greater frequencies
and concentrations in winter, whereas DDT isomers were more prevalent in summer sediment samples. Factor analysis identified
agricultural and industrial activities as major sources of sediment OCP contamination. Concentrations of γ-HCH, heptachlor
endoepoxide, dieldrin, and DDTs (isomers and metabolites) in all sediment samples were well above interim sediment quality
guidelines (ISQGs) and probable effect limits (PEL) given by Canadian Sediment Quality Guidelines (CSQGs). 相似文献