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1.
Mohamed Galal Eltarabily Abdelazim M. Negm Chihiro Yoshimura Jiro Takemura 《Environmental Modeling and Assessment》2018,23(3):289-308
Different scenarios of recharge and discharge were assessed for sustainable management of groundwater in Quaternary aquifer east of Nile Delta. MODFLOW was utilized to investigate the effect of land use change and damming construction in the upstream of the Nile River on the current and short-term groundwater management strategies. The interpretive transient simulation was performed between 2004 and 2016 after steady-state calibration in 2004, and transient state from 2004 to 2013 with different irrigation recharges associated with land use change in this period. Sensitivity analysis was performed for hydraulic conductivities, recharge, and conductance parameters. The predictive transient simulation was run till 2023 under three scenarios of increasing pumping rates by 15, 30, and 50% for agriculture expansion and specified head reduction of Port Said Canal by 0.2, 0.4, and 0.6 m associated with the reduction of Nile water levels after Grand Ethiopian Residence Dam, GERD operation in 2017. Results from the in- and out-flow budgets showed that groundwater aquifer is stable at the current rate of pumping till 2023. Groundwater heads decreased by 0.2 and 0.42 m in the southern section, and a slight increase in the northern part was noticed for the first and second scenarios, respectively. When additional pumping stress is applied (50% increase), groundwater head dropped by 0.66 m, and the storage is no longer able to maintain the aquifer capacity after 2020 (worst-case scenario). 相似文献
2.
Zhenyi Zhang Chihiro Inoue Guanghe Li 《Frontiers of Environmental Science & Engineering in China》2010,4(3):329-333
The consequence of polycyclic aromatic hydrocarbons (PAHs) in the environment is of great concern. The hydrophobic properties
of PAHs significantly impact phase distribution causing limited bioavailability. Enhanced biodegradation has been extensively
carried out by surfactants and the redeployment effect was recognized. However, the quantitative relationship concerning the
impact of solids was rarely reported. A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin (HPCD) into a mixture of phenanthrene solution and various glass beads (GB37-63, GB105-125, and GB350-500).
The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium.
A model was proposed to describe the biodegradation process. The regression results indicated that the partition coefficient
k
d (1.234, 0.726 and 0.448 L·g−1) and the degradation rate k (0 mmol·L−1: 0.055, 0.094, and 0.112; 20 mmol·L−1: 0.126, 0.141, and 0.156; 40 mmol·L−1: 0.141, 0.156 and 0.184 d−1) were positively and negatively correlated with the calculated total surface area (TSA) of solids, respectively. Degradation
enhanced in the presence of HPCD, and the enhancing factor f was calculated (20 mmol·L−1: 15.16, 40.01, and 145.5; 40 mmol·L−1: 13.29, 37.97, and 138.4), indicating that the impact of solids was significant for the enhancement of biodegradation. 相似文献
3.
Leonardo K. Miyashita Mayza Pompeu Salvador A. Gaeta Rubens M. Lopes 《Marine Biology》2010,157(11):2511-2519
We studied the population dynamics and the reproductive biology of Penilia avirostris during three consecutive years on the inner shelf off Ubatuba, Brazil. Penilia avirostris individuals and its eggs and embryos were counted, measured, and classified into stages. The species occurred throughout
the studied period, in a wide temperature range (14.8–28.2°C). Cladoceran densities were usually higher (>2,000 ind m−3) in warm seasons, when the water column was stratified as a consequence of bottom intrusions of the cold- and nutrient-rich
South Atlantic Central Water. Juveniles, non-reproducing females, and parthenogenic females were the dominant developmental
stages. Males and gamogenic females were rare and only occurred when females reached peak abundances. This suggests that in
tropical and subtropical coastal seas gamogenesis in P. avirostris is not as common as in temperate seas, but may play a significant role in the density-dependent control of the population
preceding unfavourable periods. 相似文献
4.
Zhenyi Zhang Chihiro Inoue Guanghe Li 《Frontiers of Environmental Science & Engineering》2010,4(3):329-333
The consequence of polycyclic aromatic hydrocarbons (PAHs) in the environment is of great concern. The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability. Enhanced biodegradation has been extensively carried out by surfactants and the redeployment effect was recognized. However, the quantitative relationship concerning the impact of solids was rarely reported. A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin (HPCD) into a mixture of phenanthrene solution and various glass beads (GB37-63, GB105-125, and GB350-500). The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium. A model was proposed to describe the biodegradation process. The regression results indicated that the partition coefficient k d (1.234, 0.726 and 0.448 L·g?1) and the degradation rate k (0 mmol·L?1: 0.055, 0.094, and 0.112; 20 mmol·L?1: 0.126, 0.141, and 0.156; 40 mmol·L?1: 0.141, 0.156 and 0.184 d?1) were positively and negatively correlated with the calculated total surface area (TSA) of solids, respectively. Degradation enhanced in the presence of HPCD, and the enhancing factor f was calculated (20 mmol·L?1: 15.16, 40.01, and 145.5; 40 mmol·L?1: 13.29, 37.97, and 138.4), indicating that the impact of solids was significant for the enhancement of biodegradation. 相似文献
5.
Zhenyi ZHANG Chihiro INOUE Guanghe LI 《Frontiers of Environmental Science & Engineering》2010,4(3):329
The consequence of polycyclic aromatic hydrocarbons (PAHs) in the environment is of great concern. The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability. Enhanced biodegradation has been extensively carried out by surfactants and the redeployment effect was recognized. However, the quantitative relationship concerning the impact of solids was rarely reported. A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin (HPCD) into a mixture of phenanthrene solution and various glass beads (GB37-63, GB105-125, and GB350-500). The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium. A model was proposed to describe the biodegradation process. The regression results indicated that the partition coefficient kd (1.234, 0.726 and 0.448 L·g−1) and the degradation rate k (0 mmol·L−1: 0.055, 0.094, and 0.112; 20 mmol·L−1: 0.126, 0.141, and 0.156; 40 mmol·L−1: 0.141, 0.156 and 0.184 d−1) were positively and negatively correlated with the calculated total surface area (TSA) of solids, respectively. Degradation enhanced in the presence of HPCD, and the enhancing factor f was calculated (20 mmol·L−1: 15.16, 40.01, and 145.5; 40 mmol·L−1: 13.29, 37.97, and 138.4), indicating that the impact of solids was significant for the enhancement of biodegradation. 相似文献
6.
Web spiders are considered to have expanded their habitats from dim to bright environments during the evolutionary history.
Because they are sedentary predators exposed to the sun, they may have developed a suite of adaptive traits to cope with thermal
stress. We examined the critical thermal maximum, spectral reflectance of solar energy by the body surface, and surface–volume
ratio (SVR) for 11 spider species. Analysis of the four genera having a pair of species inhabiting both bright and dim environments
showed that species in bright environments exhibited higher lethal temperatures, but spectral reflectance and SVR did not
differ. Independent contrasts using the 11 species indicated that critical thermal maximum was positively correlated with
spectral reflectance and spectral reflectance was negatively correlated with SVR. These results suggest that physiological
tolerance to high temperatures and a biophysical mechanism to reduce heat gain evolved jointly during the history of habitat
expansion in araneoid spiders. 相似文献
7.
We compared the quantity and quality of the epicuticular wax of diapause and non-diapause pupae in two closely related Pieris species, P. brassicae and P. rapae crucivora. Main components of their epicuticular wax were identified as hydrocarbons. In P. brassicae, more than 95% of hydrocarbons were saturated regardless of whether the pupae were in diapause or not. In P. rapae crucivora, 93% of hydrocarbons were saturated in non-diapause pupae whereas in diapause pupae 41% were saturated and 59% unsaturated. From measurements of body surface area by nuclear magnetic resonance microimaging, we calculated the average thickness of the wax layer. The thickness in diapause and non-diapause pupae of P. brassicae was 800 and 160 nm, respectively. In P. rapae crucivora, the thickness was 195 nm in diapause and 11 nm in non-diapause. This is the first report to clarify the compositional difference in epicuticular wax between diapause and non-diapause pupae. 相似文献
8.
Yasumasa Ogawa Kento Sakakibara Li Wang Koichi Suto Chihiro Inoue 《Environmental monitoring and assessment》2014,186(10):6757-6770
Fourteen different alkaline coal fly ashes (CFAs) were used for the experiment, in which each sample was mixed with water to be 28.6 % of water content (wt/wt) and aged for 1–4 weeks at 10–30 °C. This simple treatment is advantageous for decreases in water-soluble B, F, Cr, and As. Compared to non-aged CFAs, their water-soluble fractions remained 0.56–88 %, 21–85 %, 0.37–93 % and 2.6–88 %, respectively, after aging for a week at 20 °C, although the amounts of Cr and As released from some CFA samples increased. Considering the significant decrease in elution of sulfate, Ca and Al after aging, the immobilization, namely prevention of toxic element elution, could be related to formation of secondary minerals such as portlandite, gypsum and ettringite. Immobilization of B and Cr tends to proceed preferentially under colder conditions. Aging at higher temperatures enhances the leachability of Cr in some CFA samples. Contrary to the behavior of B and Cr, water-soluble F effectively decreases under warmer conditions. 相似文献
9.
The concentrations of bisphenol A (BPA) contained in landfill leachates from solid waste disposal sites were measured. The
concentrations of BPA contained in leachates from industrial waste sites were in the range below the detection limit to 2800 μg/l,
while those from municipal sites were in the range 26–8400 μg/l. The leachates from ash-rich sites contained relatively lower
concentrations of BPA compared with organic-rich leachates. It is suggested that BPA concentration increases with time after
the completion of reclamation in the case of ash-rich sites, whereas the concentration of BPA decreases with time in the case
of organic-rich sites. A 7-year survey on a site in Japan showed neither a decrease nor an increase in the concentration of
BPA during on-going reclamation. A leachate from a site in the Philippines contained high concentrations of BPA. A slight
positive correlation was found between BPA concentrations and total organic carbon (TOC). A major portion of the BPA in leachates
was found in dissolved and organic unassociated fractions, which cannot be precipitated by coagulation. More than 99.9% of
the BPA contained in raw leachates was removed by a conventional series of treatment processes consisting of biological treatment,
coagulation, sedimentation, sand filtration, and activated carbon adsorption.
Received: May 29, 2002 / Accepted: October 17, 2002 相似文献
10.
Remotely-Sensed Active Fire Data for Protected Area Management: Eight-Year Patterns in the Manas National Park, India 总被引:2,自引:0,他引:2
Chihiro Takahata Rajan Amin Pranjit Sarma Gitanjali Banerjee William Oliver John E. Fa 《Environmental management》2010,45(2):414-423
The Terai-Duar savanna and grasslands, which once extended along most of the Himalayan foothills, now only remain in a number
of protected areas. Within these localities, grassland burning is a major issue, but data on frequency and distribution of
fires are limited. Here, we analysed the incidence of active fires, which only occur during the dry season (Nov.–Mar.), within
a significant area of Terai grasslands: the Manas National Park (MNP), India. We obtained locations of 781 fires during the
2000–2008 dry seasons, from the Fire Information for Resource Management System (FIRMS) that delivers global MODIS hotspot/fire
locations using remote sensing and GIS technologies. Annual number of fires rose significantly from around 20 at the start
of the study period to over 90 after 2002, with most (85%) detected between December and January. Over half of the fires occurred
in tall grasslands, but fire density was highest in wetland and riverine vegetation, dry at the time. Most burning took place
near rivers, roads and the park boundary, suggesting anthropogenic origins. A kernel density map of all recorded fires indicated
three heavily burnt areas in the MNP, all within the tall grasslands. Our study demonstrates, despite some technical caveats
linked to fire detection technology, which is improving, that remote fire data can be a practical tool in understanding fire
concentration and burning temporal patterns in highly vulnerable habitats, useful in guiding management. 相似文献