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971.
Yuan Sui Samir Droby Danfeng Zhang Wenjie Wang Yongsheng Liu 《Environmental science and pollution research international》2014,21(24):13956-13963
Significant losses in harvested fruit can be directly attributable to decay fungi and quality deterioration. Hot water treatment (HWT) has been demonstrated to be an effective and economic environment-friendly approach for managing postharvest decay and maintaining fruit quality. In this study, the effects of HWT (45 °C for 10, 15, 20, and 25 min) on in vitro growth of Fusarium oxysporum, in vivo Fusarium rot, and natural decay of melon were investigated. HWT inhibited spore germination and germ tube elongation of F. oxysporum. Protein impairment and ATP consumption triggered by HWT contributed to the inhibitory effect. Results of in vivo studies showed that HWT effectively controlled Fusarium rot and natural decay of melon. Correspondingly, HWT induced a significant increase in content of total phenolic compounds and lignin of melon. These findings indicate that the effects of HWT on Fusarium rot may be associated with the direct fungal inhibition and the elicitation of defense responses in fruit. Importantly, HWT used in this study had beneficial effects on fruit quality as well. HWT may represent an effective non-chemical approach for management of postharvest Fusarium rot. 相似文献
972.
Jinxia Wang Jikun Huang Lijuan Zhang Qiuqiong Huang Scott Rozelle 《Journal of the American Water Resources Association》2010,46(4):665-685
Wang, Jinxia, Jikun Huang, Lijuan Zhang, Qiuqiong Huang, and Scott Rozelle, 2010. Water Governance and Water Use Efficiency: The Five Principles of WUA Management and Performance in China. Journal of the American Water Resources Association (JAWRA) 46(4): 665-685. DOI: 10.1111/j.1752-1688.2010.00439.x Abstract: In recent years China has attempted to reform water management by decentralizing water management responsibilities. The overall goal of our paper is to better understand the emergence of water user associations (WUAs) in China and assess if they are adhering to the practices spelled out by the Five Principles, a set of recommended practices that are supposed to lead to successful WUA operation. Using four sets of different types of villages to examine implementation and performance, we find that World Bank-supported WUA villages (“Bank villages”) can be thought of as operating mostly according to the Five Principles. For example, the Bank villages were endowed with a more reliable water supply; were set up and were operating with a relatively high degree of farmer participation; and leaders were more consultative and the process more formal. When WUAs are run according to the Five Principals, we show that WUAs increase water use efficiency. The study also provides evidence that there is a perception in the Bank villages that water management is improving in general and that there is less conflict both within the village and among villages. Perhaps more importantly, we find that the Bank’s effort to promote WUAs extended beyond their own project villages. The openness, consultative nature, and transparency found in the Bank WUAs are also found (albeit at a somewhat lower level) in the non-Bank WUA villages. 相似文献
973.
974.
The increasing volume of CO2 embodiment in international trade adds a layer of complexity to environmental policies and has raised arguments on the traditional production based responsibility for CO2 emissions. In order to help understand the quantity of CO2 embodiment in trade and its policy implications, this paper gives observations to recently emerging literatures that quantitatively discuss CO2 embodiment in trade. The analytical approaches share the principle of using input and output modeling but vary dramatically in study boundary and estimation accuracy. The calculations can be roughly categorized into three types: direct quantification of CO2 embodiments in multiregional trade, direct quantification of CO2 embodiment in bilateral trade, and indirect analysis by comparing the scenarios with or without trade. The practical estimations strongly rely on trade partner selection and data availability. An obvious imbalance of net CO2 embodiment in the commodity trade between major developed countries and developing economies as a whole was confirmed by these literatures. Carbon taxes and other possible limitations on CO2 emissions have been addressed. The consistency across the calculations could be enhanced by systematic analyses in more detail to convince the international community to take binding commitments for the reduction of global CO2 emissions. 相似文献
975.
Spatial and seasonal distribution of nitrogen in marsh soils of a typical floodplain wetland in Northeast China 总被引:3,自引:0,他引:3
Bai J Wang Q Deng W Gao H Tao W Xiao R 《Environmental monitoring and assessment》2012,184(3):1253-1263
Horizontal and profile distributions of nitrogen in marsh soils in different seasons were studied in a typical site within
the Erbaifangzi wetland in Northeast China. Results showed that there was higher spatial heterogeneity for nitrate nitrogen
(NO3--_{3}^{-}-N) and ammonium nitrogen (NH4+_{4}^{+}–N), as well as available nitrogen (AN), in surface soils in July compared to that in September. Relative to July, the mean
nitrogen contents in surface soils were slightly higher in September; however, in November, soils contained significantly
lower NO3--_{3}^{-}-N and NH4+_{4}^{+}–N, higher AN, organic nitrogen (Org-N), and total nitrogen (TN). Except for mineral nitrogen, no significant differences
were observed between Org-N and TN contents in September and November. Nitrogen contents generally declined exponentially
with depth along soil profiles in three sampling dates (July, September, and November), except for a significant accumulation
peak of NO3--_{3}^{-}-N at the 20–30 cm depth in September. However, NH4+_{4}^{+}–N contents showed a vertical alternation of “increasing and decreasing” in both July and September, while nearly kept constant
with depth in November. The depth ranking of nitrogen showed the shallowest distribution for AN, followed by Org-N and TN,
while deeper distributions for NO3--_{3}^{-}-N and NH4+_{4}^{+}–N. TN, Org-N, and AN were significantly correlated with soil organic matter and total phosphorus. Soil pH values were significantly
correlated with TN and AN contents in surface soils. Clay contents showed significant correlations with nitrogen contents
except for NO3--_{3}^{-}-N in surface soils and NH4+_{4}^{+}–N in profile soils. However, soil moisture was not significantly correlated with nitrogen contents among all soil samples. 相似文献
976.
Dynamics of the lakes in the middle and lower reaches of the Yangtze River basin, China, since late nineteenth century 总被引:1,自引:0,他引:1
Lijuan Cui Changjun Gao Xinsheng Zhao Qiongfang Ma Manyin Zhang Wei Li Hongtao Song Yifei Wang Shengnan Li Yan Zhang 《Environmental monitoring and assessment》2013,185(5):4005-4018
The middle and lower reaches of the Yangtze River basin have the most representative and largest concentration of freshwater lakes in China. However, the size and number of these lakes have changed considerably over the past century due to the natural and anthropogenic impact. The lakes, larger than 10 km2 in size, were chosen from relief maps and remotely sensed images in 1875, 1950, 1970, 1990, 2000, and 2008 to study the dynamics of lakes in the middle and lower reaches of the Yangtze River basin and to examine the causes and consequences of these changes. Results indicated that there was a dramatic reduction in lake areas, which decreased by 7,841.2 km2 (42.64 %) during the study period (1875–2008), and the number of lakes in this region changed moderately. Meanwhile, a large number of lakes in the middle and lower reaches of the Yangtze River basin were directly converted into paddy fields, ponds, building lands, or other land-use types over the study period. Therefore, all kinds of lake reclamation should be identified as the major driving factors for the loss of lake in this region. Furthermore, flooding, soil erosion, and sedimentation were also the main factors which triggered lake changes in different periods. Some wetland conservation and restoration projects have been implemented since the 1970s, but they have not reversed the lake degradation. These findings were of great importance to managers involved in making policy for the conservation of lake ecosystems and the utilization of lake resources. 相似文献
977.
Tao Y Yao S Xue B Deng J Wang X Feng M Hu W 《Journal of environmental monitoring : JEM》2010,12(12):2282-2289
Sources, partitioning and toxicological risk of 15 priority polycyclic aromatic hydrocarbons (PAHs) in surface sediments from drinking water sources of Taihu Lake, with an area of 2428 km(2) located in the most developed and populated area of China, were studied, and the results were compared with those in other lakes of China and the USA. Concentrations of the 15 PAHs in sediments ranged from 436.6 to 1334.9 ng g(-1) (dw). Gasoline combustion, coal combustion, diesel combustion from shipping and spillage of petroleum were apportioned to be the main sources of PAHs in this area by principal component analysis, which contributed 35.19%, 26.43%, 25.41% and 12.97% to the PAH sources estimated by further multiple linear regression. Levels of PAHs in sediments were negatively correlated with contents of clay and fine silt (<16 μm), while positively with contents of medium silt, coarse silt and sand (>16 μm). Humin with size larger than 16 μm contained the largest part of the burden of PAHs in sediments, but the specific partitioning domain (bound humic acid, lipid or insoluble residue) depended on properties of organic matter reflected by optical absorbance at 465 and 665 nm. Total toxic benzo[a]pyrene equivalent (TEQ(carc)) of the carcinogenic PAHs in sediments varied from 31.8 to 209.3 ngTEQ(carc) g(-1). Benzo[a]pyrene and dibenzo[a,h]anthracene contributed 45.36 and 25.31% to total TEQ(carc), posing high toxicological risk to this area. 相似文献
978.
This paper is to investigate the behavior of residents towards electrical and electronic waste (e-waste) recycling in Beijing. For this purpose a large sample questionnaire survey was performed to explore the residents’ characteristics of recycling behavior and preference of e-waste recycling pattern. Besides, the willingness of residents to participate in e-waste recycling was also assessed in our study. For this a logistic regression model was developed to estimate and explain residents’ willingness in e-waste recycling. The model showed that Convenience of recycling facilities and service, Residential conditions, Recycling habit and Economic benefits are four determinants of Beijing residents’ willingness and behavior in e-waste recycling. And centralized recycling pattern by professional recovery spots would have a broad prospect if various kinds of channels can be provided to make the residents feel more convenient in e-waste recycling. 相似文献
979.
Yongnian Ni Lin Wang Serge Kokot 《Journal of environmental science and health. Part. B》2013,48(4):328-335
A novel differential pulse voltammetry method (DPV) was researched and developed for the simultaneous determination of Pendimethalin, Dinoseb and sodium 5-nitroguaiacolate (5NG) with the aid of chemometrics. The voltammograms of these three compounds overlapped significantly, and to facilitate the simultaneous determination of the three analytes, chemometrics methods were applied. These included classical least squares (CLS), principal component regression (PCR), partial least squares (PLS) and radial basis function-artificial neural networks (RBF-ANN). A separately prepared verification data set was used to confirm the calibrations, which were built from the original and first derivative data matrices of the voltammograms. On the basis relative prediction errors and recoveries of the analytes, the RBF-ANN and the DPLS (D – first derivative spectra) models performed best and are particularly recommended for application. The DPLS calibration model was applied satisfactorily for the prediction of the three analytes from market vegetables and lake water samples. 相似文献
980.
Yanguo Teng Dan Feng Liuting Song Jinsheng Wang Jian Li 《Environmental monitoring and assessment》2013,185(11):9559-9569
In order to investigate the distribution of the total petroleum hydrocarbons (TPH) in groundwater and soil, a total of 71 groundwater samples (26 unconfined groundwater samples, 37 confined groundwater samples, and 8 deeper confined groundwater samples) and 80 soil samples were collected in the Songyuan oilfield, Northeast China, and the vertical variation and spatial variability of TPH in groundwater and soil were assessed. For the groundwater from the unconfined aquifer, petroleum hydrocarbons were not detected in three samples, and for the other 23 samples, concentrations were in the range 0.01–1.74 mg/l. In the groundwater from the confined aquifer, petroleum hydrocarbons were not detected in two samples, and in the other 35 samples, the concentrations were 0.04–0.82 mg/l. The TPH concentration in unconfined aquifer may be influenced by polluted surface water and polluted soil; for confined aquifer, the injection wells leakage and left open hole wells may be mainly responsible for the pollution. For soils, the concentrations of TPH varied with sampling depth and were 0–15 cm (average concentration, 0.63 mg/g), >40–55 cm (average concentration, 0.36 mg/g), >100–115 cm (average concentration, 0.29 mg/g), and >500–515 cm (average concentration, 0.26 mg/g). The results showed that oil spillage and losses were possibly the main sources of TPH in soil. The consequences concluded here suggested that counter measures such as remediation and long-term monitoring should be commenced in the near future, and effective measures should be taken to assure that the oilfields area would not be a threat to human health. 相似文献