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21.
Sheikh Saeed Ahmad Patrick Biiker Lisa Emberson Rabia Shabbir 《Water, air, and soil pollution》2011,220(1-4):141-150
Nitrogen dioxide is an important gaseous air pollutant. It plays a major role in atmospheric chemistry, particularly in the formation of secondary air pollutants, and contributes to environmental acidification. A comprehensive assessment of NO2 levels in the atmosphere is required for developing effective strategies for control of air pollution and air quality improvement. Air pollution is a serious problem in all major cities of Pakistan and needs to be addressed to minimize detrimental effects on human health and urban vegetation. In this research, we focused on the monitoring of NO2 levels in the urban environment of Rawalpindi city. Because of the lack of expensive continuous sampling devices and to get a good spatial coverage of the NO2 concentrations in the study area, NO2 passive samplers were exposed at 42 different sites within the city limits of Rawalpindi from January to December, 2008. Samplers were exchanged every 10 days and the associated meteorological conditions like temperature, wind speed, rainfall and relative humidity were also monitored. The average NO2 concentration was found to be 27.46?±?0.32 ppb. The highest values of NO2 were measured near to main roads and educational institutions due to intense flow of road vehicles. Moreover, the study showed that the values obtained for NO2 for all sampling points exceeded the annual limit value set by World Health Organization. So, this is very important to take different steps to control this before it becomes a serious hazard for people living in those areas. 相似文献
22.
Sheila M. Pereira Almas Begum Dr. Bienvenido O. Juliano 《Plant foods for human nutrition (Dordrecht, Netherlands)》1981,31(2):97-108
The effect of high protein milled rices (IR480-5-9 and IR2153-338-3, 10% protein) on the nitrogen retention and growth of preschool Indian children was assessed in two feeding trials in a residential home. The children were offered, ad libitum, a rice-based diet in four meals daily without vitamin and mineral supplement. The children in the experimental group were given the high protein rice; those in the control group were given a local rice (7% protein). The groups had similar percent apparent digestibility and retention of dietary nitrogen. Statistically significant differences in increase in height and weight between the two groups were not consistently observed at the end of 4.5 to 5 months or 1 year. Possible factors contributing to these results are discussed. 相似文献
23.
M. A. Kader S. Sleutel S. A. Begum A. Z. M. Moslehuddin S. De neve 《European Journal of Soil Science》2013,64(1):47-57
The nitrogen (N) requirement for paddy rice cultivated in Bangladesh amounts to approximately 80 kg N ha?1. Lack of knowledge on N mineralization from soil organic matter leads farmers to meet this N requirement exclusively by costly mineral fertilizers, which have typically an efficiency of less than 40%. We assessed to what extent routinely analysed soil properties (N and carbon (C), texture, pH, extractable iron (Fe), aluminium (Al) and manganese (Mn), soil mineralogy and length of the annual inundation period) are able to predict net aerobic and anaerobic N mineralization in paddy soils. Both soil N and C correlated positively with the aerobic but not with the anaerobic N mineralization rate. Instead, relative anaerobic N mineralization showed a significant negative correlation with soil N content. We observed no significant influence of clay mineralogy on soil N mineralization. Aerobic but not anaerobic N mineralization increased with length of the annual inundation period while the proportion of the soil N that was mineralized during 120 days decreased. The large clay content of fields that are inundated for 9–10 months annually explains the co‐occurrence of large soil N contents and relatively small N mineralization rates in these fields. However, variation in texture did not explain variation in N mineralization of soils with inundation periods of 3–8 months. Instead, the anaerobic N mineralization correlated positively with Na pyrophosphate‐extractable Fe and negatively with pH (both at P < 0.01). Thus, pH and Fe content, rather than soil N content, clay mineralogy or texture, explained the substantial variation in anaerobic N mineralization of paddy soils in Bangladesh inundated for 3–8 months. It is not known if these relationships between net evolution of ammonium in soil and pH and Fe content are causal or indirect. Elucidation of these mechanisms would greatly further our comprehension of the biochemistry of the young ‘floodplain soils' with relatively low content of pedogenic oxides throughout southeast Asia. 相似文献
24.
Ferdousi Begum Feroza Hossain Md. Rafiqul Islam Mondal 《Archives of Agronomy and Soil Science》2016,62(2):261-276
An experiment was conducted to study the biochemical response of rapeseed (Brassica campestris L.) to sulphur (S) fertilization at grey terrace soil. There were five treatments: S0 (control), S1 (20 kg S ha?1), S2 (40 kg S ha?1), S3 (60 kg S ha?1) and S4 (80 kg S ha?1). Chlorophyll content in the leaf was determined at 30, 40, 50 and 60 days after emergence (DAE). The biochemical properties were found responsive to S. The highest chlorophyll content of mustard leaves was found in 60 kg S ha?1 at 50 DAE. The same treatment also showed the maximum N content in the leaves at 45 DAE. The highest oil content was recorded in 60 kg S ha?1. Other chemical characters such as acid value, peroxide and saponification values were lowest in 60 kg S ha?1 while iodine value was found highest in the same S level. Non-essential fatty acids such as palmitic, stearic and erucic acid were increased in the rapeseed with decrease in S level, whereas essential fatty acids were maximum in 60 kg S ha?1. Therefore, 60 kg S ha?1 can be recommended to produce quality rapeseed in grey terrace soil of Bangladesh. 相似文献
25.
Hafeez-ur-Rehman Mahmood Ayyaz Muhammad Nadeem Husn Ara Begum 《Russian Agricultural Sciences》2017,43(2):149-152
The present study was conducted to screen four okra varieties (Sabz Pari, Sada Bahar, Pusa Sawani, Arka Anamika) against bollworm, whitefly and jassid under field conditions during 2011. It was concluded that none of the tested variety had resistance against okra fruit borer. However, these varieties showed some degree of resistance against sucking insect pests. Okra variety Sada Bahar was less infested with jassid (1.30/leaf) and whitefly (5.36/leaf) compared to other tested varieties and resulted in maximum yield (1529.62 kgha–1). The plants of Sabz Peri variety attained maximum height (113.7 cm), which was statistically at par with 110.9 cm height attained by the plants of Arka Anamika. Number of fruits pods plant–1 was found non significantly different on all the tested okra varieties. On the basis of present findings, it was concluded that Sada Bahar variety is suitable for cultivation in Dera Ismail Khan and other parts of the country with similar environmental conditions. 相似文献
26.
Gunda Schulte auf'm Erley Nazma Begum Mosisa Worku Marianne Bänziger Walter J. Horst 《植物养料与土壤学杂志》2007,170(1):106-114
Nitrogen efficiency is a complex trait. Identification of secondary plant traits correlating with N efficiency would facilitate the breeding for N‐efficient cultivars. Sixteen tropical maize cultivars differing in grain yield at low N supply (N efficiency) under field conditions in Zimbabwe exhibited a significant negative correlation between N efficiency and leaf senescence during grain filling. The same cultivars were studied for leaf senescence under N deficiency in a short‐term nutrient‐solution experiment. Leaf chlorophyll contents as estimated by SPAD values and photosynthesis rates were used as measures for leaf senescence. Cultivars differed both in SPAD values and photosynthesis rates of the older leaves during N deprivation. Significant negative correlations were found between SPAD values, photosynthesis rates in the nutrient‐solution experiment, and leaf‐senescence scores in the field experiments, and positive correlations were found between photosynthesis rates and grain yield under low‐N conditions in the field. Relationships between physiological root parameters, which were also investigated in the nutrient‐solution experiment, and N uptake or grain yield of the cultivars in the field could not be established. It is concluded, that the assessment of the capacity of a genotype to maintain a higher photosynthetic capacity of older leaves during N deficiency–induced senescence at the seedling stage is a suitable selection parameter for the N efficiency of tropical maize cultivars. 相似文献
27.
Ghousia Begum 《Fish physiology and biochemistry》2011,37(1):61-69
The acute effect of carbofuran, a carbamate insecticide, was studied on adenosine triphosphatase enzymes in gill, kidney,
liver and muscle tissues of a food fish, Clarias batrachus. Glycogen and glycogen phosphorylase were investigated in gill and kidney only. Thirty-six fish were exposed to sublethal
concentration (7.6 mg/L) for 6 days. After 6 days, 18 fish were released into freshwater in order to study the recovery response.
Eighteen fish were kept in clean water as control. Tissues were isolated from control, exposed and recovery fish at the end
of 1, 3 and 6 days and used for the assay of enzymes. Total ATPase was inhibited in kidney and muscle tissues throughout the
exposure period, whereas branchial and hepatic tissues showed initial induction followed by inhibition. Na+-K+ ATPase activity was induced in gill till day 3, whereas in other tissues inhibition was throughout the exposure period. Mg+2 ATPase activity was inhibited in all tissues except liver. When the fish were released into freshwater, liver recovered almost
to control values and other tissues showed organ-specific response. Glycogen content of gill increased initially followed
by decrease, and in kidney initial decrease was noted. The recovery response was more in kidney than in gill. Induction in
the activity of glycogen phosphorylases was observed in kidney, whereas gill tissue showed mixed response. Recovery was not
observed in phosphorylases. Thus, the results of the present study demonstrated the acute effect of carbofuran on a food fish
and organ-specific recovery response to insecticidal treatment. 相似文献
28.
Ahmad Sheikh Saeed Büker Patrick Emberson Lisa Shabbir Rabia 《Water, air, and soil pollution》2012,223(2):955-955
Water, Air, &; Soil Pollution - 相似文献
29.
OBJECTIVES: To examine the efficiency of the Bangladesh Integrated Nutritional Program (BINP) in identifying which infants should be supplemented, whether full supplementation was given for the stipulated period of time, and whether the correct exit criteria from the supplementation programme were used. To test whether targeted food supplementation of infants between 6-12 months of age resulted in enhanced weight gain. SETTING: Mallickbari Union, Bhaluka, a rural area located about 100 km north of Dhaka, Bangladesh. PARTICIPANTS: Five hundred and twenty-six infants followed for 6 to 12 months. RESULTS: Of the 526 infants studied, 368 should have received supplementation based on BINP criteria but only 111 infants (30%) did so, while a further 13% were incorrectly given supplementation. So in total over half (52.8%) of the sample was incorrectly identified for supplementation. In addition, less than a quarter of the infants received the full 90 days of supplementation and close to half of the infants exited the programme without the requisite weight gain. Infants were assigned to one of four groups: correctly supplemented, correctly non-supplemented, incorrectly supplemented or incorrectly non-supplemented. This classification provided natural controls; the correctly supplemented infants versus the incorrectly non-supplemented infants, and the correctly non-supplemented infants versus the incorrectly supplemented infants. There were no significant differences in weight gain between the correctly supplemented group and the incorrectly non-supplemented group or between the correctly non-supplemented and the incorrectly supplemented groups, nor was there any evidence of growth faltering in the incorrectly non-supplemented group. CONCLUSIONS: This study found serious programmatic deficiencies - inability to identify growth faltering in infants, failure to supplement for the full time period and incorrect exit procedures. There was no evidence that food supplementation had any impact on improving infant weight gain. 相似文献
30.
Majid Mahmood Tahir Shahida Begum Mehdi Maqbool Abdul Khaliq Noosheen Zahid Khalid Mehmood Muhammad Shehzad 《植物养料与土壤学杂志》2021,184(1):132-141
Background : Poor utilization of urea fertilizer and N losses from agriculture lands demands alternate fertilization practices to reduce N losses and improve utilization, i.e., application of nitrification inhibitors. Aims : This study was aimed to evaluate and compare the influence of dicyandiamide (DCD) and selected medicinal plant materials and on N transformations, nitrification inhibition and recovery of applied N. Methods : Treatments included: urea nitrogen (UN), UN + DCD, UN + Gingiber officinale, UN + Viola odorata, UN + Sewertia chirata, UN + Azadirachta indica, UN + Sphaenathus indicus, UN + Allium sativus, UN + Artemisia absenthium, UN + Fumaria indicus, UN + Caesalpinea bondusella, UN + Barberis lyceum, and an un‐amended control. Urea was applied at 200 mg N kg?1 soil, while DCD and medicinal plant materials were applied at of 1% and 20% of applied urea, respectively. Results : Medicinal plant materials inhibited nitrification of urea‐derived . On an average of medicinal plant materials treatments, 51% of was still present in soil compared to 17% in UN treatment without medicinal plant materials after 28 days. Similarly, was 76.54 mg kg?1 in UN treatment compared to 34.40 mg kg?1 in UN + medicinal plant materials treatments, indicating 55% reduction in nitrification. Apparent nitrogen recovery (ANR) in UN treatment was 65% compared to 74% in UN + DCD treatment. ANR in treatments, where UN was amended with medicinal plant materials, varied between 58 to 70%. Conclusions : The use of DCD and medicinal plant materials with UN significantly reduced oxidation and nitrification ( ). In general, medicinal plant materials were more effective in regulating N transformations and, thus, offer a suitable alternate fertilization practice to reduce N losses and improve fertilizer utilization. 相似文献