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131.
Silicon is considered a beneficial nutrient for sugarcane (Saccharum spp.) and yield responses to Si applications on Florida organic soils have been well documented. Growers need calibrated Si recommendations to be able to make cost-effective decisions regarding Si applications. The objective of this study was to develop a soil-test Si calibration based on yield responses to Ca silicate on Everglades Histosols. Twelve paired commercial field comparisons and three small-plot tests of Ca silicate application were conducted. Strong responses in t cane ha?1 and t sucrose ha?1 were determined with acetic acid-extractable soil Si <15 g m?3, with some response to approximately 25 g m?3. Recommendations were developed over this range with a maximum Ca silicate rate of 6.7 t ha?1. Optimum leaf Si concentration was determined to be ≥ 6.0 g kg?1, with 0.95 and 0.80 relative yield at 5.0 and 2.5 g kg?1, respectively. 相似文献
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133.
The hydraulic potential stimulation of magnesium is significant to its direct utilization. In this paper, magnesium slag which is the main material, and some slag and activator are used to prepare cementitious material and bricks, and the influences of different activators on the hydraulic properties are also investigated. Experiments show a certain hydraulic potential of magnesium slag but with a low strength, however, the compressive strength soars from 1.8 MPa to 27 MPa after composing it with a small amount of blast-furnace slag. The early strength of magnesium slag-blastfurnace slag binder is affected by NaOH, while the gypsum affects the binder’s later strength. Bricks conforming to standard MU20 are successfully fabricated by 80% magnesium and 20% blast furnace slag, after activated, with extra 5% desulfurized gypsum. 相似文献
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135.
城市生活垃圾焚烧炉渣对水体中磷的去除效果 总被引:1,自引:0,他引:1
城市生活垃圾焚烧炉渣对水体中的磷有较好的去除效果,当初始磷浓度低于200 mg/L时,炉渣对磷的去除率接近100%;当初始磷浓度为800 mg/L时,炉渣对磷的去除率接近60%.炉渣对磷的吸附符合Langmuir和Freundlich等温吸附模型,相关系数均达显著水平.Langmuir吸附等温线模拟炉渣的吸附磷性能优于Freundlich模型,根据Langmuir方程计算出炉渣对磷的理论饱和吸附量为26 162 mg/kg.炉渣对磷的吸附受pH值的变化影响不大,磷的解析率低,且其重金属浸出浓度低,环境安全性能优良.综上所述,生活垃圾焚烧炉渣是一种较为理想的除磷吸附剂. 相似文献
136.
[目的]为研究采煤塌陷对土壤水分、养分以及生态环境的影响。[方法]将兖州采煤塌陷区作为研究对象,采用野外调查和室内测试分析等方法。[结果]采煤塌陷不仅促使土壤水分由坡顶到塌陷中心点迁移,而且导致垂直剖面上的土壤含水量变化明显。在垂直剖面上,随着深度的增加,土壤的含水量增大。受采煤塌陷和地下潜水的影响,60 cm深度之下含水量迅速增加。采煤塌陷还导致土壤养分从塌陷地坡顶到塌陷中心点发生迁移流失,并且在塌陷中心点发生富集。土壤养分在0~20 cm深度含量达到最大,并且随着深度的增加,养分含量降低。此外,由于受塌陷等因素的影响,塌陷区的生态环境遭到一定程度的破坏。[结论]应对采煤塌陷加以足够的重视,并进行更深入的研究。 相似文献
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139.
重庆市酉阳县秸秆煤替代煤炭烤烟技术研究 总被引:2,自引:0,他引:2
[目的]开发利用我国丰富的秸秆类生物质能源。[方法]将秸秆煤与原煤烤烟的成本及化学成分含量进行对比研究。[结果]秸秆煤不仅完全可以满足烤烟工艺要求,而且一定程度上改善了烟叶的品质;秸秆煤烤烟能够减少烘烤成本,减少上部叶烟碱含量,提高烟叶的评吸质量。经测定,2 hm2地的烟秆碳化后加工成蜂窝煤,基本可以满足1 hm2地烤烟需要。[结论]采用秸秆煤烘烤烟叶,烟叶的内在质量得以提高,同时可以降低环境污染以及减少资源的浪费,是一种十分可行的烤烟加工技术。 相似文献
140.
Long-Term Effects of Fluidized Bed Combustion Material Applied at Disposal Levels on Soil Properties
《Communications in Soil Science and Plant Analysis》2012,43(12):1720-1731
This study was conducted to assess changes in soil properties of a soil that received a one-time application (360 Mg ha?1) of fluidized bed combustion material (FBCM) 23 years earlier. Soil samples were taken at three depths (0–10, 10–20, and 20–30 cm). Samples were also collected from an adjacent field with the same soil type for control. Hot nitric acid and Mehlich 3 extractions were used for total and extractable elements. Analyses indicated improvement in soil physical and chemical properties after 23 years of FBCM application. For example at the 20- to 30-cm depth, soil pH values increased from 4.9 to 7.7, whereas calcium concentrations increased from 0.23 to 1.52 g kg?1 with FBCM amendment. In most cases, metal concentrations were less with FBCM amendment. Results from this study demonstrated that soil physical and chemical improvements from FBCM were maintained even 23 years after an extremely high application of FBCM. 相似文献