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71.
72.
Spentwash is a rich source of organic matter and essential plant nutrients in addition to excess salts. Sugar mills in Pakistan discharge about 3.48 million tons of spentwash annually, with no proper procedures for its disposal or utilization. To test the effect of diluted spentwash on soil and the soil’s ability to support plant growth, sugarcane (Saccharum officinarum L.) variety CPF-237 was planted. The experiment was conducted in a randomized complete block design involving factorial combination of four concentrations of each spentwash (0, 10, 20, and 30%) and mineral fertilizers (0, 1/3, 2/3, and the full recommended rate of NP). The 10% spentwash plus 2/3 mineral fertilizer treatment substituted 33% each of N and P and 100% of K, saving mineral fertilizer cost (Rs. 48600 ~ US$458) in addition to 29.54% increase in yield over full NP fertilizer. The same treatment also improved the soil organic matter (65%), N (20%), P (25%), and K (230%) over full NP treatment alone. An increase in the salt content of the soil was detected within the prescribed limits, with the exception of HCO3.  相似文献   
73.
It is frequently argued that, at the parcel level, 1 stakeholders are capable of and well supported in managing their land‐related risks. Yet, evidence from the contemporary Australian context suggests otherwise: numerous large‐scale disaster events have revealed that citizens are ill‐prepared to respond and recover adequately. This paper begins with the premise that information, specifically land information, could better support parcel‐level risk preparation, mitigation, response, and recovery. State land administration organisations in Australia primarily maintain this information and make it accessible. Land information is used regularly across all levels of government to support risk management activities; however, such application has not always occurred at the parcel and citizen level. Via a case study approach, this paper initially explores the land information available in Australia to stakeholders interested in parcel‐level detail, and then goes on to propose how the utilisation of parcel‐level land information could serve to enhance risk management practices.  相似文献   
74.
Environmental Science and Pollution Research - In developing countries like Pakistan, agriculture constitutes the primary source of support for the majority of rural and the adjacent urban...  相似文献   
75.
Nanosized Ba1- xBixFe1-xCuxO3(12–50 nm) with x values of 0, 0.01, 0.05, and 0.1 system was prepared using the Pechini method. Structural, morphological, surface and optical characterizations were performed for the prepared samples. Cubic phase was the predominant phase for the undoped BaFeO3 and Bi and Cu co-doped BaFeO3 samples. Minor phases of monoclinic Ba2Fe2O5, orthorhombic BaFe  相似文献   
76.
This paper discusses the sensitivity of the value of information to the risk aversion in two-action decision problems when the initial wealth is uncertain. We demonstrate that there is no general monotonicity between information value and the Arrow–Pratt risk aversion in this setting. We then show that monotonicity exists in the sense of Rubinstein’s measure of risk aversion when the lottery is independent of the initial wealth. Finally, we show that if the lottery is dependent on the initial wealth, then Ross’s measure of risk aversion is needed to characterize this monotonic relation. Our results explain the shape of the sensitivity analysis curve of the value of information to risk aversion and interpret various measures of risk aversion based on their monotonicity with information value.  相似文献   
77.
Wasi S  Jeelani G  Ahmad M 《Chemosphere》2008,71(7):1348-1355
Pseudomonas fluorescens SM1 isolate was found to be resistant to some major water pollutants namely Cd2+, Cr6+, Cu2+, Ni2+, Pb2+, BHC, 2,4-D, mancozeb and phenols up to a concentration four times to the normal levels occurring in the highly pollulated regions. Curing experiment brought about the loss of one or more resistance markers indicating the plasmid born resistance. Plasmid profile of SM1 strain showed the presence of one DNA band of 43.6 kb. This Plasmid was isolated from SM1 strain and introduced into Escherichia coli DH5 alpha with a transformation frequency of 6.7 x 10(-4)transformants/recipient cell. The test SM1 strain was also capable of biotransforming Cr(VI) to Cr(III) which is less toxic compounds. Present studies further indicated that the test SM1 strain was not only resistant to 2,4-D, phenols and catechol but also capable of bioremediating these toxicants quite efficiently. Moreover, studies with inhibitors like sodium azide, 2,4-DNP and chloramphenicol suggested that the major mechanism for the bioremediation of the heavy metals other than Cr6+ would be the biosorption process.  相似文献   
78.
The City of Amman, Jordan, has been subjected to persistent increase in road traffic due to overall increase in prosperity, fast development and expansion of economy, travel and tourism. This study investigates traffic noise pollution in Amman. Road traffic noise index L 10(1 h) was measured at 28 locations that cover most of the City of Amman. Noise measurements were carried out at these 28 locations two times a day for a period of one hour during the early morning and early evening rush hours, in the presence and absence of a barrier. The Calculation of Road Traffic Noise (CRTN) prediction model was employed to predict noise levels at the locations chosen for the study. Data required for the model include traffic volume, speed, percentage of heavy vehicles, road surface, gradient, obstructions, distance, noise path, intervening ground, effect of shielding, and angle of view. The results of the investigation showed that the minimum and the maximum noise levels are 46 dB(A) and 81 dB(A) during day-time and 58 dB(A) and 71 dB(A) during night-time. The measured noise level exceeded the 62 dB(A) acceptable limit at most of the locations. The CTRN prediction model was successful in predicting noise levels at most of the locations chosen for this investigation, with more accurate predictions for night-time measurements.  相似文献   
79.
Participatory environmental management can empower communities and enhance the sustainability of environmental interventions. However, existing power structures and inequalities along class, gender, or ethnic lines could prevent part of the community from accessing the full benefits of the intervention. An analysis of determinants of the willingness-to-participate in an environmental intervention in a Beirut neighborhood is conducted. Socioeconomic, health-risk distribution, and perception of community efficacy are used as predictors. A randomly selected sample of residents was surveyed. Respondents were asked to specify the frequency with which they were willing to be involved in an intervention to address priority environmental problems in the neighborhood. Bivariate and multivariate ordinal regression analyses were conducted. Tests of significance were based on the 95% confidence intervals (CI) of the odds ratio (OR). Males versus females (OR = 4.89, P < 0.001), respiratory patients versus nonsufferers (OR = 5.65, P < 0.001), tenants versus house owners (OR = 2.98, P < 0.01), and the less educated versus the more educated (OR = 2.42, P < 0.05) were significantly more likely to be willing to participate. The reluctance of female community members to participate might be a major hindrance to community-based environmental protection and special strategies must be devised to overcome it. On the other hand, respondents suffering from an illness perceived to be related to environmental toxins are likely to be strong participants in environmental conservation efforts. Finally, the study yielded no evidence that belief or lack of it in the efficacy of community action is a good predictor of the willingness-to-participate in such action.  相似文献   
80.
A thorough understanding of past and present hydrologic responses to changes in precipitation patterns is crucial for predicting future conditions. The main objectives of this study were to determine temporal changes in rainfall‐runoff relationship and to identify significant trends and abrupt shifts in rainfall and runoff time series. Ninety‐year rainfall and runoff time series datasets from the Gasconade and Meramec watersheds in east‐central Missouri were used to develop data screening procedure to assess changes in the rainfall and runoff temporal patterns. A statistically significant change in mean and variance was detected in 1980 in the rainfall and runoff time series within both watersheds. In addition, both the rainfall and runoff time series indicated the presence of nonstationary attributes such as statistically significant monotonic trends and/or change in mean and variance, which should be taken into consideration when using the time series to predict future scenarios. The annual peak runoff and the annual low flow in the Meramec watershed showed significant temporal changes compared to that in the Gasconade watershed. Water loss in both watersheds was found to be significantly increasing which is potentially due to the increase in groundwater pumping for water supply purposes.  相似文献   
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