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61.
Kuntal M. Hati Ashis K. Biswas Kalikinkar Bandyopadhyay Arun K. Misra 《植物养料与土壤学杂志》2004,167(5):584-590
Post‐methanation effluent (PME) generated through bio‐methanation of distillery effluent, a foul‐smelling, dark colored by‐product of distillery industries, is applied to arable land in some areas near the vicinity of the distillery industries as an amendment. The PME contains considerable amount of organic matter and salt besides its high plant‐nutrient content. The present investigation was conducted for three years during 1999–2002 on soybean‐wheat cropping sequence to evaluate the effect of graded levels of post‐methanation effluent (PME) on soil physical properties and crop productivity in a deep Vertisol of central India. Six application doses of PME viz. S2.5+W0: 2.5 cm PME applied to soybean and wheat on residual nutrition, S2.5+W1.25: 2.5 cm PME to soybean and 1.25 cm to wheat, S5.0+W0: 5 cm PME to soybean and wheat on residual nutrition, S5.0+W2.5: 5.0 cm PME to soybean and 2.5 cm to wheat, S10.0+W0: 10 cm PME to soybean and wheat on residual nutrition, and S10.0+W5.0: 10.0 cm PME to soybean and 5.0 cm to wheat, were compared with 100% recommended NPK+FYM ? 4 Mg ha–1 and control (no fertilizer, manure or PME). The application of PME increased the organic carbon content and electrical conductivity of the soil compared to control and 100% NPK+FYM treatment. The organic C content was maximum in S10.0+W5.0 (11.2 g kg–1) and minimum in control (5.2 g kg–1). Electrical conductivity increased from 0.47 dS m–1 in control to 1.58 dS m–1 in highest dose of PME (S10.0+W5.0). The PME treatments have not affected the soil pH. The application of PME showed a significant improvement in the physical properties of the soil. The mean weight diameter (MWD), percent water‐stable aggregation (% WSA), saturated hydraulic conductivity (Ksat), and water retention (WR) at 0.033 MPa suction were significantly (P < 0.05) more while bulk density (BD) and penetration resistance was significantly less in PME‐treated plots than that of control. The MWD showed a linear and positive relationship (r = 0.89**) with the soil organic C. Soybean recorded significantly higher seed yield at all PME treatments than control. Highest average soybean yield (2.39 Mg ha–1) was recorded in S10.0+W0 but yield decreased significantly in S10.0+W5.0 (2.08 Mg ha–1). In wheat, all the PME‐treated plots except S2.5+W0 yielded significantly higher than control while the 100% NPK+FYM treatment yielded (3.46 Mg ha–1) at par with the S10.0+W5.0 (4.0 Mg ha–1) and S5.0+W2.5 (3.66 Mg ha–1). Fresh application of PME to wheat resulted in significant improvement in grain yield over that grown on residual fertility. Thus, application of PME to arable land, as an amendment, could be considered as a viable option for the safe disposal of this industrial waste. 相似文献
62.
Shil Bikash Lahiri Biswajit Pal Prasenjit Ghosh Amitava Biswas Pradyut Singh Yumlembam Jackie 《Aquaculture International》2022,30(4):2017-2041
Aquaculture International - Most of the adoption studies in catfish culture were restricted to feeding habits, growth rate and morphological studies, neglecting the social factors and adoption of... 相似文献
63.
Kartik Baruah Asim K. Pal Narottam P. Sahu Dipesh Debnath Parisa Nourozitallab Patrick Sorgeloos 《Journal of the World Aquaculture Society》2007,38(1):129-137
Abstract.— A feeding trial was conducted for 60 d to study the effect of dietary microbial phytase on growth performance and nutrient digestibility of rohu, Labeo rohita , fingerlings. One hundred and twenty fingerlings (average initial weight: 9.17 g/fish) were equally distributed into five experimental tanks, each with four replicates. Five isonitrogenous (35%) and isocaloric (16.79 kJ/g) diets were prepared from plant-based ingredients, supplemented with microbial phytase at the level of 0, 250, 500, 750, and 1000 U/kg diets and fed to T0 , T1 , T2 , T3 , and T4 groups, respectively. Weight gain %, food conversion ratio, protein efficiency ratio, and apparent net protein utilization were significantly ( P < 0.05) improved in groups fed phytase-supplemented diets compared to control, the highest being observed in T3 group. Maximum apparent digestibility of phosphorus and crude protein was recorded in T3 group. Bone ash, phosphorus (P), and calcium (Ca) contents were also significantly ( P < 0.05) increased in phytase-fed groups. However, maximum was recorded in T3 group. Results from the present study indicated that addition of 750 U microbial phytase/kg diets effectively improved nutrient utilization, bone mineralization, and hence growth of L. rohita fingerlings. 相似文献
64.
Shivendra Kumar Narottam P Sahu Asim K Pal Dharitri Choudhury & Subhas C Mukherjee 《Aquaculture Research》2006,37(3):284-292
A feeding trial was conducted for 60 days to delineate the effect of both gelatinized and non‐gelatinized corn with or without supplementation of exogenous α‐amylase at two level of protein 35% (optimum) and 27% (sub‐optimum) on growth, tissue composition and protein sparing effect of carbohydrate in the diet of Labeo rohita fingerlings. Three hundred and sixty fingerlings (average weight 10.00±0.15 g) were randomly distributed in 12 treatment groups with two replicates for each. Twelve semi‐purified diets containing either 35% or 27% CP were prepared with different levels of α‐amylase (0, 50, 100 and 150 mg kg?1) and starch type [gelatinized (G)/non‐gelatinized, (NG)] viz. T1 (NG, 35% CP, 0 mg kg?1α‐amylase), T2 (G, 35% CP, 0 mg kg?1α‐amylase), T3 (NG, 27% CP, 50 mg kg?1α‐amylase), T4 (NG, 35% CP, 50 mg kg?1α‐amylase), T5 (G, 27% CP, 50 mg kg?1α‐amylase), T6 (G, 35% CP, 50 mg kg?1α‐amylase), T7 (NG, 27% CP, 100 mg kg?1α‐amylase), T8 (NG, 35% CP, 100 mg kg?1α‐amylase), T9 (G, 27% CP, 100 mg kg?1α‐amylase), T10 (G, 35% CP, 100 mg kg?1α‐amylase), T11 (NG, 27% CP, 150 mg kg?1α‐amylase) and T12 (NG, 35% CP, 150 mg kg?1α‐amylase). The fish were acclimatized to the experimental condition for 24 days during which control diet (NG, 35% CP) was fed. Weight gain percentage, specific growth rate, protein efficiency ratio and apparent net protein utilization of NG corn‐fed groups at 42.43% were significantly higher (P<0.05) than the same level of G corn‐fed groups. We conclude that 42.43% NG corn supplemented with 50 mg α‐amylase kg?1 feed at sub‐optimum level of CP (27%) significantly enhanced the growth and protein in L. rohita fingerling. Addition of dietary α‐amylase to G corn had no added advantage on growth of L. rohita fingerling. 相似文献
65.
Two consecutive feeding trials were conducted to know: (i) how the apparent digestibility coefficient (ADC) varies among replicates
on different days and during the course of the experiment (Trial 1); and (ii) the effect of stocking density (e.g. 7.17, 5.56,
and 3.92 kg fish/t water) on the ADC of nutrients and energy in red sea bream (Trial 2). In both trials, 0.5% Cr2O3 was used as an inert marker. In Trial 1, there were no significant differences in ADC within the replicates although the
values on different days varied significantly during the second week. The ADC of all parameters in the third and fourth weeks
was significantly higher than in the second week (P<0.05). Although statistically insignificant, the lower stocking densities (3.92 and 5.56 kg fish/t water) showed better growth
performance and superior ADC of protein, lipid, and energy than the higher stocking density in Trial 2. The results indicated
that it may be better to acclimate fish to the diet for at least three weeks to obtain more reliable data by using a single
tank for each treatment for digestibility experiments. Results also indicated that growth and digestibility performance can
be stimulated by controlling stocking density. 相似文献
66.
Identifying scale specific controls of soil water storage in a hummocky landscape using wavelet coherency 总被引:1,自引:0,他引:1
Asim Biswas 《Geoderma》2011,165(1):50-59
High spatio-temporal variability of soil water is contributed from different ecohydrological and soil processes operating in different intensities at different scales. Traditional Pearson correlation analysis only examines linear correlation at the measurement scale. In this study, the correlation between soil water storage and its controlling factors was examined at different scales and locations in a hummocky landscape using wavelet coherency. Time domain reflectometry and neutron probe were used to measure soil water storage up to 1.4 m depth along a transect of 576 m long established in a hummocky landscape at St. Denis National Wildlife Area, Saskatchewan, Canada. In spite of visual similarity of the spatial pattern of soil water storage and elevation, the value of Pearson correlation coefficient was very small. However, wavelet coherency identified strong scale- and location-specific correlations between soil water storage and elevation. The total area of significant correlations as calculated from the total number of significant coherencies at different scales and locations was higher between soil water storage and elevation than between soil water storage and any other factors, which indicated a dominant control from elevation on soil water storage in the hummocky landscape. The largest area of significant correlation was observed at large scales (> 70 m), which can be attributed to the alternating knolls and depressions. The relationship between soil water storage and elevation at different scales was persistent at different times of the year or at different seasons with a slight reduction in the magnitude of correlation. The persistent relationship indicated the dominant control from elevation with slight change in the degree of the control. The scale-location specific correlation provides a complete picture on the controls of soil water storage, which was not possible with traditional correlation analysis. 相似文献
67.
68.
69.
Anirban Biswas Saroni Biswas Rama Venkata Srikanth Lavu Prakash Chandra Gupta Subhas Chandra Santra 《Paddy and Water Environment》2014,12(3):379-386
Rice is prone to arsenic accumulation compared to other cereals as typically grown up under waterlogged situation favoring arsenic mobility. Arsenic in rice depends on arsenic availability to plants from irrigation water, even differs among cultivars and their plant parts. Present study was concentrated on arsenic accumulation in various plant parts of five common rice cultivars grown using irrigation water from different water sources in various fields in arsenic-endemic region. Additionally, dose response experiment under laboratory net house was conducted on the same cultivars excluding open environmental factors. The common cultivars were categorized according to high to low arsenic accumulator in rice grain, straw and root parts. The cultivar Shatabdi has shown highest arsenic accumulation in rice grain compared to other rice cultivars in fields and when grown at various soil arsenic doses. In field samples, a highest grain arsenic concentration ranged between 0.69 ± 0.04 and 0.78 ± 0.12 mg kg?1 for Shatabdi, whereas lowest grain arsenic concentration ranged between 0.37 ± 0.07 and 0.41 ± 0.07 mg kg?1 for the cultivars GB3 and Lalat. Speciation study detected more inorganic arsenic than organoarsenicals with a trend of arsenite > arsenate > DMA > MMA, which would be problem for consumers. The concluding remark is the characterization of common rice cultivars according to arsenic concentration to highlight an important remediation strand by changing to low arsenic cultivar. 相似文献
70.
A. Biswas 《European Journal of Soil Science》2014,65(4):594-604
Information on the spatial variability of soil water storage (SWS) at different scales is important for understanding various hydrological, ecological and biogeochemical processes in the landscape. However, various obstructions such as roads or water bodies may result in missing measurements and create an irregular spatial series. The wavelet transform can quantify spatial variability at different scales and locations but is restricted to regular measurements. The objective of this study was to analyse the spatial variability of SWS with missing measurements using the second‐generation continuous wavelet transform (SGCWT). Soil water content (converted to SWS by multiplying with depth) was measured with a neutron probe and time‐domain reflectrometry along a transect of 128 points. Because there were missing measurements, I used SGCWT to partition the total variation into different scales and locations. Whilst there were some small‐scale variations (< 20 m) along the transect, the medium scale variations (20–70 m with an average of about 30–45 m) were mainly concentrated within the depressions along the transect. The strongest variations were observed at around 90–110 m scale, representing the variations resulting from alternating knolls and depressions. Similar spatial patterns at different scales were observed during different seasons, indicating temporal stability in the spatial pattern of SWS. Among the controlling factors, the wavelet spectra of relative elevation (RE) and organic carbon (OC) were very similar to that of SWS. The wavelet covariance was also large between SWS and RE and OC at all seasons. As the OC reflects the long‐term history of water availability and might be controlled by topographic setting or elevation, it can be concluded that elevation is an important controlling factor of SWS irrespective of seasons in this type of landscape. The SGCWT provides a new way of analysing the spatial variability of regularly measured soil properties or those with missing measurements. 相似文献