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81.
When agricultural lands are no longer used for agriculture and allowed to recover its natural vegetation, soil organic carbon
can accumulate in the soil. Measurements of soil organic carbon and aggregate stability changes under various forms of land
use are needed for the development of sustainable systems. Therefore, comparison of soil samples taken from both agricultural
and nearby area close to land-mined fields where no agricultural practices have been done since 1956 can be a good approach
to evaluate the effects of tillage and agriculture on soil quality. The objective of this study was to compare tillage, cropping
and no tillage effects on some soil-quality parameters. Four different locations along the Turkey–Syria border were selected
to determine effects of tillage and cropping on soil quality. Each location was evaluated separately because of different
soil type and treatments. Comparisons were made between non-tilled and non-cropped fallow since 1956 and adjacent restricted
lands that were tilled about every 2 years but not planted (T) or adjacent lands tilled and planted with wheat and lentil
(P). Three samples were taken from the depths of 0–20 and 20–40 cm each site. Soil organic carbon (SOC), pH ,electrical conductivity,
water soluble Ca++, Mg++, CO3-2{\rm CO}_{3}^{-2} and HCO3-{\rm HCO}_{3}^{-}, extractable potassium (K+) and sodium (Na+), soil texture, ammonium (NH4+{\rm NH}_{4}^{+}–N) and nitrate (NO3–N), extractable phosphorous and soil aggregate stability were determined. While the SOC contents of continuous tillage without
cropping and continuous tillage and cropping were 2.2 and 11.6 g kg−1, respectively, it was 30 g kg−1 in non-tilled and non-planted site. Tillage of soil without the input of any plant material resulted in loss of carbon from
the soil in all sites. Soil extractable NO3−N contents of non-tilled and non-cropped sites were greatest among all treatments. Agricultural practices increased phosphorus
and potassium contents in the soil profile. P2O5 contents of planted soils were approximately 20 to 39 times greater than those of non-tilled and non-cropped soils at different
sites. FTIR spectra showed that never tilled sites had greater phenol, carboxylic acid, amide, aromatic compounds, polysaccharide
and carbohydrates than other treatments. 相似文献
82.
Monavari SM Omrani GA Karbassi A Raof FF 《Environmental monitoring and assessment》2012,184(4):1841-1846
Environment problems associated with the generation of waste are part of societal changes where households play an important
role. These societal changes influence the size, structure and characteristic of given households. For the effective planning
of solid-waste handling infrastructure, it is essential to know the quantity of waste generation and its composition. This
paper presents the findings of a study carried out in an urban municipal area in Iran to determine the household solid-waste
generation rate and waste composition based on field surveys and to determine the related socioeconomic parameters. The dependent
variables were waste generation and composition, and independent variables were family size, family employment, age, number
of room and education. Over 400 sample households were selected for the study using a stratified random sampling methodology
and from five different socioeconomic groups. Waste collected from all groups of households were segregated and weighted.
Waste generation rate was 5.4 kg/household/day. Household solid waste comprised of ten categories of wastes and with the largest
component (76.9%). The generation and composition of household solid waste were correlated with family size, education level
and households income. This paper adequately suggests new insights concerning the role of socioeconomic parameters in affecting
the generation of household waste. 相似文献
83.
Yassine Charabi Ali Al-Bulooshi Sultan Al-Yahyai 《Environmental monitoring and assessment》2013,185(3):2329-2342
In this paper, COSMO numerical weather prediction model is used to simulate land-sea breeze circulation in the north coast of Oman and to analyze the variability of the PBL depth. Typical summer day 1st August 2009 and winter day 1st January 2009 were simulated and verified by surface observations. The COSMO model was initialized using the German global model which runs as 40 km resolution and 40 vertical layers. The simulations show differences in the onset, strength, and inland penetration of the sea breeze. The high sea-land thermal contrast in the summer season induces earlier onset and progression of the sea breeze with larger horizontal and vertical extents. The summer and winter inland penetration is simulated around 150 and 65 km, respectively. The PBL depth was defined from the verticals profiles of the turbulence kinetic energy (TKE). The simulated PBL height varied at 1,600 m in summer and 700 m in the winter case. These results are in general in good agreement with the simulations of the National Centers for Environmental Prediction Global Data Assimilation System (NCEP-GDAS) model. The dispersive ability of the atmosphere was tested through the vertical mixing coefficient (VMC) generated by NCEP-GDAS simulations. The VMC during the summer simulated case is approximately four times larger than the respective one during the winter case. Consequently, during the advection of winter sea breeze, a shallow dome less than 100 m is shaped and forms an obstacle to the air-pollutant dispersion. 相似文献
84.
85.
Smaeyl Hassanzadeh Omid Hajrasouliha Ali Rezaei Latifi 《Environmental Modeling and Assessment》2016,21(6):721-730
The Persian Gulf ecosystem is facing a variety of stresses as a result of being located within the richest oil province in the world, which hosts more than 67 % of the world oil reserve. In this paper, the distribution of oil pollution on the surface layer of the Persian Gulf is predicted for the different months after the release, based on the Coupled Hydrodynamical Ecological model for Regional Shelf seas (COHERENS). An Eulerian model for the Persian Gulf is set up using the Cartesian coordinate in the horizontal direction, and the sigma coordinate in the vertical direction. Based on this model, our analysis and simulation results indicate that the winds lead to diffusion of the contaminant concentration in the direction of the Arabian coast from the initial position of the spill. The results of this study can be used to provide appropriate solutions for preventing oil from spreading further in the region. 相似文献
86.
Shams Ali Baig Zimo Lou Muzaffar Ali Baig Muhammad Qasim Dilawar Farhan Shams Qaisar Mahmood Xinhua Xu 《Environmental monitoring and assessment》2017,189(4):194
Corrosion deposits formed within drinking water distribution systems deteriorate drinking water quality and resultantly cause public health consequences. In the present study, an attempt was made to investigate the concurrent conditions of corrosion scales and the drinking water quality in selected water supply schemes (WSS) in districts Chitral, Peshawar, and Abbottabad, northern Pakistan. Characterization analyses of the corrosion by-products revealed the presence of α-FeOOH, γ-FeOOH, Fe3O4, and SiO2 as major constituents with different proportions. The constituents of all the representative XRD peaks of Peshawar WSS were found insignificant as compared to other WSS, and the reason could be the variation of source water quality. Well-crystallized particles in SEM images indicated the formation of dense oxide layer on corrosion by-products. A wider asymmetric vibration peak of SiO2 appeared only in Chitral and Abbottabad WSS, which demonstrated higher siltation in the water source. One-way ANOVA analysis showed significant variations in pH, turbidity, TDS, K, Mg, PO4, Cl, and SO4 values, which revealed that these parameters differently contributed to the source water quality. Findings from this study suggested the implementation of proper corrosion prevention measures and the establishment of international collaboration for best corrosion practices, expertise, and developing standards. 相似文献
87.
Annabi A Messaoudi I Kerkeni A Said K 《Environmental monitoring and assessment》2009,155(1-4):459-465
This study aims to demonstrate the influence of animals' origin on their sensitivity toward heavy metals. For this purpose, we compared LC(50) of cadmium in two populations of Gambusia affinis captured in two geographically isolated environments in the east of Tunisia; Oued El Gsil in the city of Monastir (S2) and Oued Chenini in the region of Gabes (S1). Although physicochemical parameters of the water (pH, dissolved oxygen and salinity) are similar in the two studied sites, cadmium concentrations in water, sediments and fish tissues from S1 are significantly higher (P < 0.01) than those from S2, 48-h and 96-h LC(50) of the (S1) population are significantly higher than those from S2. In the same way, the offspring of the polluted site (S1) population exhibit 48-h and 96-h LC(50) values much higher than those of the reference site (S2) population. These results show that the population of the Gabes region is more resistant to cadmium than that of the Monastir region and that this resistance could have a genetic basis. These results indicate the influence of the origin of animals that has to be taken into account not only in laboratory toxicity tests, but also in field ecotoxicological studies. 相似文献
88.
Günlü A Kadioğullari AI Keleş S Başkent EZ 《Environmental monitoring and assessment》2009,148(1-4):127-137
Recognition and understanding of landscape dynamics as a historical legacy of disturbances are necessary for sustainable management of forest ecosystems. This study analyzes spatial and temporal changes in land use and forest cover patterns in a typical mountain forest area in Rize Forest Enterprise of the Northeastern part of Turkey. The area is investigated by evaluated the temporal changes of spatial structure of forest conditions through spatial analysis of forest cover type maps from 1984 and 2007 using GIS and FRAGSTATS. The quantative evidences presented here showed that there were drastic changes in the temporal and spatial dynamics of land use/forest cover. As an overall change between 1984 and 2007, there was a net decrease of 2.30% in total forested areas. On one hand, productive forest areas decreased 12,506 ha, on the other hand, degraded forest areas increased 14,805 ha. In examining the changes of crown closure and development stages of forest ecosystem during the study period, the forest stand area with medium crown closures increased. Regenerated area increased while the other development stages were left to grow to mature development stages in the period. These results regarding to crown closure and development stage showed that forest quality has increased but total forest areas decreased. This is partially due to out-migration of rural population in Rize and Cayeli towns. In terms of spatial configuration, analysis of the metrics revealed that landscape structure in Study area had changed substantially over the 23-year study period, resulting in fragmentation of the landscape as indicated by the large patch numbers and the smaller mean patch sizes due to heavy timber subtraction, illegal cutting, and uncontrolled stand treatments. 相似文献
89.
Ali Duran Mustafa Tuzen Mustafa Soylak 《Environmental monitoring and assessment》2014,186(7):4619-4628
Regular consumption of fish has been widely recommended by health authorities. However, it is known that some species accumulate high levels of contaminants including heavy metals (e.g., Hg, Cd, Pb, and As). In this study, Cu, Pb, Co, Ni, Cr, Mn, Cd, and Fe were determined in the muscle tissue of 11 commercially available fish species (Sparus auratus, Dicentrarchus labrax, Mullus barbatus, Belone belone, Psetta maxima, Epinephelus aeneus, Salmothymus, Soleidae, Pomatomus saltatrix, Engraulis encrasicolus, and Sarda sarda) supplied from retailers in Kayseri, Turkey. Determinations were carried out by flame atomic absorption spectrometry after the wet digestion method. The average metal concentrations of the 11 species were determined in the range of 0.54–1.79, 0.82–1.40, 2.38–4.54, 1.23–3.67, 5.01–5.97, 0.77–3.59, 0.48–1.06, and 5.05–122.8 μg/g wet weight for Cu, Pb, Co, Ni, Cr, Mn, Cd, and Fe, respectively. The permissible tolerable daily intake (PTDI) and calculated daily intake (CDI) values were compared, and the calculated daily intake values of the samples were found to be below the established values. Correlations between the metal contents in samples were investigated by performing correlation tests with SPSS 13.0 for windows. 相似文献
90.
Akansha Bhatia Sangeeta Madan Jitendra Sahoo Muntjeer Ali Ranjana Pathania Absar Ahmed Kazmi 《Waste management (New York, N.Y.)》2013,33(7):1595-1601
Bacterial diversity of full scale rotary drum composter from biodegradable organic waste samples were analyzed through two different approaches, i.e., Culture dependent and independent techniques. Culture-dependent enumerations for indigenous population of bacterial isolates mainly total heterotrophic bacteria (Bacillus species, Pseudomonas species and Enterobacter species), Fecal Coliforms, Fecal Streptococci, Escherichia coli, Salmonella species and Shigella species showed reduction during the composting period. On the other hand, Culture-independent method using PCR amplification of specific 16S rRNA sequences identified the presence of Acinetobacter species, Actinobacteria species, Bacillus species, Clostridium species, Hydrogenophaga species, Butyrivibrio species, Pedobacter species, Empedobactor species and Flavobacterium species by sequences clustering in the phylogenetic tree. Furthermore, correlating physico-chemical analysis of samples with bacterial diversity revealed the bacterial communities have undergone changes, possibly linked to the variations in temperature and availability of new metabolic substrates while decomposing organics at different stages of composting. 相似文献