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101.
Y Kooch SM Hosseini C Zaccone H Jalilvand SM Hojjati 《Journal of environmental monitoring : JEM》2012,14(9):2438-2446
Following the ratification of the Kyoto Protocol, afforestation of formerly arable lands and/or degraded areas has been acknowledged as a land-use change contributing to the mitigation of increasing atmospheric CO(2) concentration in the atmosphere. In the present work, we study the soil organic carbon sequestration (SOCS) in 21 year old stands of maple (Acer velutinum Bioss.), oak (Quercus castaneifolia C.A. Mey.), and red pine (Pinus brutia Ten.) in the Darab Kola region, north of Iran. Soil samples were collected at four different depths (0-10, 10-20, 20-30, and 30-40 cm), and characterized with respect to bulk density, water content, electrical conductivity, pH, texture, lime content, total organic C, total N, and earthworm density and biomass. Data showed that afforested stands significantly affected soil characteristics, also raising SOCS phenomena, with values of 163.3, 120.6, and 102.1 Mg C ha(-1) for red pine, oak and maple stands, respectively, vs. 83.0 Mg C ha(-1) for the control region. Even if the dynamics of organic matter (OM) in soil is very complex and affected by several pedo-climatic factors, a stepwise regression method indicates that SOCS values in the studied area could be predicted using the following parameters, i.e., sand, clay, lime, and total N contents, and C/N ratio. In particular, although the chemical and physical stabilization capacity of organic C by soil is believed to be mainly governed by clay content, regression analysis showed a positive correlation between SOCS and sand (R = 0.86(**)), whereas a negative correlation with clay (R = -0.77(**)) was observed, thus suggesting that most of this organic C occurs as particulate OM instead of mineral-associated OM. Although the proposed models do not take into account possible changes due to natural and anthropogenic processes, they represent a simple way that could be used to evaluate and/or monitor the potential of each forest plantation in immobilizing organic C in soil (thus reducing atmospheric C concentration), as well as to select more appropriate species during forestation plan management at least in the north of Iran. 相似文献
102.
Human milk is usually the only source of food for infants during the first 4 to 5 months of their life. Maternal environmental
mercury exposure is directly related to fish consumption or amalgam filling. In this research, 38 human milk samples were
collected from mothers of Lenjan area who were not occupationally exposed with mercury. Mercury concentration in human milk
was determined by AMA254 Mercury Analyzer. A level of mercury was examined in relation to somatometric, demographic and dental
amalgam parameters. Obtained results showed that only dental amalgam significantly increased the mercury level in human milk
(p < 0.001). The mean mercury concentrations in milk of mothers without teeth fillings (n = 13), with one to three teeth fillings (n = 10), and four to eight teeth fillings (n = 15) were 2.87, 5.47, and 13.33 μg/l, respectively. The result of this study also showed a positive correlation of mercury
milk levels with the number of teeth fillings of the mother (p < 0.05, r = 0.755). The estimated weekly intake of mercury of a breastfed infant in this study was, in some cases, higher than provisional
tolerance weekly intake recommended by FAO/WHO, which pose a threat to their health. 相似文献
103.
Characterization of ionic composition of TSP and PM10 during the Middle Eastern Dust (MED) storms in Ahvaz, Iran 总被引:1,自引:0,他引:1
Shahsavani A Naddafi K Jaafarzadeh Haghighifard N Mesdaghinia A Yunesian M Nabizadeh R Arhami M Yarahmadi M Sowlat MH Ghani M Jonidi Jafari A Alimohamadi M Motevalian SA Soleimani Z 《Environmental monitoring and assessment》2012,184(11):6683-6692
Because of the recent frequent observations of major dust storms in southwestern cities in Iran such as Ahvaz, and the importance of the ionic composition of particulate matters regarding their health effects, source apportionment, etc., the present work was conducted aiming at characterizing the ionic composition of total suspended particles (TSP) and particles on the order of ~10?μm or less (PM(10)) during dust storms in Ahvaz in April-September 2010. TSP and PM(10) samples were collected and their ionic compositions were determined using an ion chromatography. Mean concentrations of TSP and PM(10) were 1,481.5 and 1,072.9?μg/m(3), respectively. Particle concentrations during the Middle Eastern Dust (MED) days were up to four times higher than those in normal days. Ionic components contributed to only 9.5% and 11.3% of the total mass of TSP and PM(10), respectively. Crustal ions were most abundant during dust days, while secondary ions were dominant during non-dust days. Ca(2+)/Na(+) and Cl(-)/Na(+) ratios can be considered as the indicators for identification of the MED occurrence. It was found that possible chemical forms of NaCl, (NH(4))(2)SO(4), KCl, K(2)SO(4), CaCl(2), Ca(NO(3))(2), and CaSO(4) may exist in TSP. Correlation between the anionic and cationic components suggests slight anion and cation deficiencies in TSP and PM(10) samples, though the deficiencies were negligible. 相似文献
104.
Mohammad Miri Elham Akbari Abdeltif Amrane Seyed Javad Jafari Hadi Eslami Edris Hoseinzadeh Mansur Zarrabi Javad Salimi Mohsen Sayyad-Arbabi Mahmoud Taghavi 《Environmental monitoring and assessment》2017,189(11):583
The heavy metal (Pb, Cd, Cr, and Ni) content of a fish species consumed by the Sistan population and its associated health risk factors were investigated. The mean concentrations of Pb, Cd, and Cr were slightly higher than the standard levels. The Ni content of fish was below the maximum guideline proposed by the US Food and Drug Administration (USFDA). The average estimated weekly intake was significantly below the provisional tolerable intake based on the FAO and WHO standards for all studied metals. The target hazard quotients (THQ) of all metals were below 1, showing an absence of health hazard for the population of Sistan. The combined target hazard quotient for the considered metals was 26.94 × 10?3. The cancer risk factor for Pb (1.57 × 10?7) was below the acceptable lifetime carcinogenic risk (10?5). The results of this study reveal an almost safe level of Pb, Cd, Cr, and Ni contents in the fish consumed by the Sistan population. 相似文献
105.
Seyed Hamidreza Sadeghi Shirko Ebrahimi Mohammadi Vijay P. Singh Kamran Chapi 《Environmental monitoring and assessment》2017,189(5):238
The temporal variability of phosphorus (P) transport and the relationships between discharge, suspended sediment concentration and particulate (PP), and soluble (SP) phosphorus were examined. The study was conducted at the event scale in seven tributaries of the Zarivar Lake watershed in Kurdistan Province (Iran) from March 2011 to April 2012. Based on eight runoff events, 82% of the total P was the PP carried out by suspended sediment. Results showed a high variability of P transport during different runoff events. It was found that soil erosion was the source of the high P load. For all tributaries, PP was linearly related to both discharge and suspended sediment concentration. However, the relationships of SP and PP with discharge and suspended sediment concentration showed different hysteresis patterns. The relationship between PP and discharge was generally characterized by a clockwise pattern (i.e., lower part contribution of the sub-watersheds) but the patterns between SP and discharge were mainly anticlockwise (i.e., upper part contribution of the sub-watersheds or perhaps due to a subsurface flow contribution). 相似文献
106.
Behrooz RD Esmaili-Sari A Ghasempouri SM Bahramifar N Covaci A 《Environment international》2009,35(2):285-290
Persistent organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), alpha, beta and gamma-hexachlorocyclohexane (HCH) isomers, together with polychlorinated biphenyl (PCB) congeners (IUPAC Nos. 28, 52, 101, 138, 153 and 180), were determined in tail feathers from 37 birds belonging to 18 species, all originating from the South-West of Iran (Khuzestan, coast of the Persian Gulf). This is the first report on organochlorine contaminants in feathers from museum collections and it is an indication of the concentrations of OCPs and PCBs in the past (1991-1996). Median concentrations of HCHs, DDTs, PCBs and HCB were 22, 14, 11 and 10 ng/g feather, respectively. Significant correlations (p<0.05) were calculated between OCPs (except HCB) and PCBs in the bird feathers. p,p'-DDE and gamma-HCH were the most abundant OCPs, while CB 180, CB 138 and CB 101 were the predominant PCB congeners in almost all species. Significant differences (p<0.05) in the mean concentrations of DDTs and PCBs were detected among species grouped according to their feeding habits. Levels of DDTs and PCBs were highest in the carnivorous species and lowest in the herbivorous species. Levels of OCPs and PCBs in feathers of bids in the 1990s were generally below the thresholds reported to affect reproduction. 相似文献
107.
Abdolinejhad Fatemeh Khayati Gholam Reza Raiszadeh Ramin Yaghoobi Nahid Sadat Khorasani Seyed Mohammad Javad 《Journal of Material Cycles and Waste Management》2021,23(5):1855-1872
Journal of Material Cycles and Waste Management - In this study, a hybrid of support vector regression and a modified tunicate swarm algorithm (SVR-MTSA) strategy is developed to optimize the... 相似文献
108.
Environment Systems and Decisions - This paper proposes a framework to systematically evaluate and select attributes of decision models used in disaster risk management. In doing so, we formalized... 相似文献
109.
Nemati Tayebeh Sarkheil Mehrdad Johari Seyed Ali 《Environmental science and pollution research international》2019,26(10):9610-9618
Environmental Science and Pollution Research - We investigated the trophic transfer potential of CuO-NPs from Artemia salina to Amatitlania nigrofasciata. The Cu uptake was investigated by exposure... 相似文献
110.
Ahmad Barati Asieh Aliakbari Seyed Mahmoud Ghasempouri 《Russian Journal of Ecology》2011,42(4):315-320
Variations in breeding success of the Whiskered Terns (Chlidonias hybrida) were studied in two wetlands; Anzali (2005 and 2008) and Zarivar (2007–2008) in north and west Iran. Nesting success was
modeled and compared using information-theoretic approach implemented in program Mark in order to assess effects of colony
locations, years and nest initiation dates on the probability of daily nest survival. Clutch size did not vary between colonies
and years. Breeding success varied between colonies (Zarivar > Anzali), and years only in Anzali (2005 > 2008). Overall daily
nest survival was 0.977. (95% LCI 0.973, UCI 0.981), equivalent to a Mayfield nest survival of 0.317. (95% LCI 0.255, UCI
0.387). Egg-laying periods and colony site were important covariates affecting the daily survival rates (Σω
i
= 0.86 and Σω
i
= 0.83, respectively), while, the support for the effect of year was less (Σω
i
= 0.41). We concluded that Lake Zarivar provides a more favorable nesting location for Whiskered Terns probably because of
little changes in rainfall and water depth during the breeding seasons which influence breeding performance. 相似文献