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1.
Abstract. In a laboratory study, 15 N ammonium fertilizer uptake and rice growth was determined in a non-acid sulphate marine soil (Typic Tropaquept) and an acid sulphate soil (Sulfic Tropaquept). Acid sulphate sensitive (IR 26) and acid sulphate tolerant (IR 46) rice varieties were grown in soil suspensions incubated at four Eh levels (+500, +250, +50, and -150 mV) in microcosms for three weeks. The results showed that rice grown in non-acid sulphate marine soils gave slightly better dry matter weight of 1.8g/pot, greater 15 N uptake of 12.8 mg N/pot, and higher total N uptake of 38.4 mg N/pot than under acid sulphate soil conditions indicating the non-acid marine soil is more favourable to rice culture. Growth as measured by weight of dry matter was significantly reduced from 2.1g/pot under oxidized condition (+500 mV) to 0.8g/pot under highly reduced condition (-150 mV). N uptake by rice was significantly reduced from 16.9 mg/pot at + 500 mV to 4.5 mg N/pot at -150 mV Total N uptake also decreased with decreasing Eh. Growth, 15 N uptake and total N uptake by acid sulphate tolerant rice, IR 46 were significantly higher than the acid sulphate sensitive rice variety, IR 26. Under highly reduced soil conditions (-150 mV), growing rice in acid sulphate soil would require additions of lime, intermittent irrigation and/or mid season drainage in order to increase soil redox potential and remove toxic substances. 相似文献
2.
Methane emission and entrapment in flooded rice soils as affected by soil properties 总被引：7，自引：0，他引：7
Z. P. Wang C. W. Lindau R. D. Delaune W. H. Patrick Jr. 《Biology and Fertility of Soils》1993,16(3):163-168
Laboratory incubation experiments were conducted to study the effects of soil chemical and physical properties on CH4 emission and entrapment in 16 selected soils with a pH range of 4.7–8.1, organic matter content of 0.72–2.38%, and soil texture from silt to clay. There was no significant correlation with CH4 emission for most of the important soil properties, including soil aerobic pH (measured before anaerobic incubation), total Kjeldahl N, cation exchange capacity, especially soil organic matter, and soil water-soluble C, which were considered to be critical controlling factors of CH4 emission. A lower CH4 emission was observed in some soils with a higher organic matter content. Differences in soil Fe and Mn contents and their chemical forms contributed to the this observation. A significant correlation between the CH4 emission and the soil organic C content was observed only after stratifying soils into subgroups according to the level of CH4 emission in soils not amended with organic matter. The results also showed that the soil redox potential (Eh), anaerobic pH, anerobic pH, and biologically reducible Fe and Mn affected CH4 emission significantly. Urea fertilization promoted CH4 emission in some soils and inhibited it in others. This result appeared to be related to the original soil pH. CH4 entrapment was positively correlated with soil clay content, indicating the importance of soil physical characteristics in reducing CH4 emissions to the atmosphere. 相似文献
3.
A. Jugsujinda R. D. Delaune C. W. Lindau E. Sulaeman S. R. Pezeshki 《Water, air, and soil pollution》1996,87(1-4):345-355
Methane and C02 production in flooded acid sulfate soils of Thailand were governed primarily by soil oxidation-reduction potential (Eh) and pH. The critical Eh and pH levels at which CH4 emission began was Eh-150 mV, and pH 6.1. Low soil pH limited soil reduction and subsequently CH4 production. Soil respiration (C02 production) was influenced by Eh-pH levels and organic matter content. Soils with higher C02 production rates produced greater amounts of CH4. Soil pH, however, was the dominant variable which influenced organic matter decomposition, low soil Eh conditions and subsequent CH4 and CO2 production. Curvilinear or log transformations of pH, Eh and organic matter content (OM) were used in explaining variables controlling CH4 and CO2 production; CH4 = ?2.359 ? 0.0001 Eh + 2.047 pH ? 3.019 (In pH)2 CO2 = ?5210 ? 1.6 Eh + 3144 (In pH) + 1011 (In OM). 相似文献
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5.
Delaune R. D. Lindau C. W. Sulaeman E. Jugsujinda A. 《Water, air, and soil pollution》1998,106(1-2):149-161
The transformations of applied (100 kg N ha-1)15 N labelled NO3 and NH4 in Mississippi River deltaic plain swamp forest soil which receives agriculture run-off from adjacent sugarcane fields were determined. Using an isotopic dilution technique, the rates of NO3 production (nitrification) and reduction in the 15NO3 treated soil-water-columns were approximately 240 and 2,320 g N ha-1 d-1, whereas NH4 production (mineralization) and removal rates in the 15NH4 treated soil-water-columns were 270 and 2160 g N ha-1 d-1, respectively. It was shown that if nitrification and NH4 assimilation were the primary processes responsible for NH4 removal, average NH4 assimilation would be 145 g N ha-1 d-1. Based on labelled N2-emission, denitrification was 3 fold greater in the NO3 treatment compared to the NH4 treated soil water-columns with rates of 818 and 266 g N ha-1 d-1 respectively. Even though the rate was lower in the NH4 treatment, results show that nitrification-denitrification of NH4 is a significant process. Nitrogen losses determined by15 N2 emissions were 20.4 and 6.4% and N2O emissions were 0.10 and 0.03% of the applied NO3-N and NH4-N, respectively, over 32 days of incubation. Fertilizer loss through N2O emission was only of minor significance compared to the fertilizer loss through N2 evolution. Nitrous oxide fluxes from the control soil-water-columns averaged 9.4 g N ha-1 d-1. Addition of NO3-N to the columns increased N2O production 56% as compared to a 15% increase from the NH4-N addition. Results show that this wetland soil has a large capacity to process inorganic nitrogen entering the system as a result of agriculture run-off. 相似文献
6.
Field studies were conducted to evaluate Sagittarialancifolia sensitivity to in-situ burning of appliedcrude oil. Twenty-four plots were constructed (2.4 × 2.4× 0.6 m) in a fresh marsh and experimental treatmentswere: 1) control (no oiling and/or burning); 2) oiling (naturalremediation); and 3) oiling plus burning. South Louisiana Crudewas applied at 2 L m-2, with a garden sprayer, on Sagittaria lancifolia stems and leaves of the oiling andoiling/burning treatment plots. Two marsh burns were conducted,one in August (Site A) and a second on separate plotsthe following April (Site B) to compare seasonal effects ofoiling and burning. Burning was initiated three days after oilapplication when the marsh was flooded to a 15–25 cm depth andwinds were calm. Live stem count, plant height growth and carbonfixation were measured up to 9 times over 52 weeks after thefirst burn (August) and 6 times over 19 weeks after the secondin-situ burn (April). Aboveground biomass was measured atthe conclusion of each study. Oil application and oil burninghad short term effects on Sagittaria lancifoliavegetation. Five to six weeks after each burn, measured Sagittaria lancifolia vegetative parameters in control, oiledand oiled/burned plots were not significantly different. Onlybiomass clipped 20 weeks after the April burn showed significanttreatment differences. Under our experimental conditions, datasuggests leaving oil to degrade and the marsh to recovernaturally may be an option to consider. Plant recovery inoiled/burned plots was as rapid as oiled plant recovery. Thissuggests burning may be a viable remediation method if a rapidresponse is needed to remove oil and control oil migration tosensitive areas. 相似文献
7.
Methane mitigation in flooded Louisiana rice fields 总被引：6，自引：0，他引：6
C. W. Lindau P. K. Bollich R. D. DeLaune A. R. Mosier K. F. Bronson 《Biology and Fertility of Soils》1993,15(3):174-178
Summary A field experiment was conducted to determine whether selected nitrification inhibitors (encapsulated calcium carbide and dicyandiamide) and SO
inf4
sup-2
-containing compounds [(NH4)2SO4 and Na2SO4] had mitigating effects on CH4 emissions from flooded rice. Microplots were established within a rice bay drill-seeded with the Texmont rice cultivar and CH4 fluxes were measured over the main rice cropping season. Methane emissions over the 77-day sampling period were approximately 230, 240, 260, 290, 310, and 360 kg CH4 ha-1 from the calcium carbide, Na2SO4-rate II, Na2SO4-rate I, (NH4)2SO4, dicyandiamide, and urea (control) treatments, respectively. Reductions in CH4 evolution, compared to the control, ranged from 14 to 35%, depending on treatment. The selected inhibitors and SO
inf4
sup-2
-containing compounds appear to be effective in reducing the CH4 emitted from flooded rice fields. 相似文献
8.
A. Bufogle Jr. P. K. Bollich J. L. Kovar R. E. Macchiavelli C. W. Lindau 《Journal of plant nutrition》2013,36(9):1203-1224
Differences in nitrogen (N) use by different varieties of rice (Oryza sativa L.) have been reported by numerous researchers. Some have indicated that N fertilization required for maximum yield differs between modern varieties and old varieties (varieties no longer in production); others have suggested that among modern varieties, semidwarf varieties require higher N rates than taller varieties. The objectives of this study were to evaluate differences in dry matter and N accumulation among modern long‐grain varieties in relation to plant stature (tall versus semidwarf) and maturity group (early versus very early), and to compare old varieties and modern varieties. A greenhouse pot experiment with Crowley silt loam (fine, montmorillonitic, thermic Typic Albaqualf) was conducted to compare old and modern long‐grain varieties at 52 days after sowing. Based on the results of the pot experiment, three varieties each from six variety groups (old varieties, modern medium‐grain varieties, and four groups of modern long‐grain varieties) were planted in the field on Crowley silt loam soil. Each variety was fertilized with three preflood N levels (0, 67, and 135 kg N ha‐1). Plants were harvested 49 days after sowing and 25 days after 50% heading. Old and modem long‐grain varieties did not differ in total N accumulation at any N level. However, long‐grain varieties produced more grain than the old varieties at all N levels, and among long‐grain varieties, semidwarf varieties produced more grain than tall varieties when 135 kg N ha‐1 were applied. Early and very early varieties did not differ in total N accumulation or grain yield. Varieties that produced a higher grain yield did so by partitioning more N to grain than straw. Modern medium‐grain varieties accumulated more N than old and long‐grain varieties and produced more grain with both 67 and 135 kg N ha‐1. Medium‐grain varieties had a higher harvest index and physiological efficiency than old varieties but did not differ from long‐grain varieties. This suggests that medium‐grain varieties also partition more of their N into grain than straw and possibly are able to absorb more N from soil than old or long‐grain varieties. 相似文献
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C. W. Lindau R. D. Delaune W. H. Patrick Jr. E. N. Lambremont 《Water, air, and soil pollution》1989,48(3-4):489-496
In many coastal areas of Louisiana, surface water quality is deteriorating rapidly due to elevated nutrient input from agricultural, domestic and industrial sources. This study investigates the potential use of natural abundance variations in 15N/14N ratios for identification and tracing surface water inorganic N sources. Surface water samples were collected from streams and point sources in Louisiana and analyzed for NH4 +-N, NO3 ?-N and associated 15N/14N (δ15N ‰) concentrations. Ammonium-N from domestic sewage and industrial discharge point sources was found to have distinct δ15N ranges. Domestic sewage discharge into a slow flowing stream was traced for about 30 km downstream using 15N/14N ratios. At the sewage point source NH4 +-δ15N values averaged +43%o and increased linearly to +162‰ with distance from the discharge. In a larger stream with a greater flow velocity the NH4 +-δ15N surface water signature of an industrial discharge source was identifiable for approximately 1 km from the point source. Surface water NO3 ?-°15N values generally ranged from +1 to +99‰ and no significant association was observed between δ15N values with distance from the domestic sewage and industrial point sources. The discrete NH4 +-δ15N signatures of domestic sewage and industrial point sources compared to downstream surface water NH4 +-δ15N values suggest that N isotopic ratios have the potential to be used as tracers in surface waters contaminated with inorganic N. 相似文献