Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar Central University, Raibarelly Road, Lucknow 226025, Uttar Pradesh, India.
Ecotoxicol Environ Saf. 2013 Mar;89:43-51. doi: 10.1016/j.ecoenv.2012.11.011. Epub 2012 Dec 20.
There are reports that the application of fly ash, compost and press mud or a combination thereof, improves plant growth, soil microbial communities etc. Also, fly ash in combination with farmyard manure or other organic amendments improves soil physico-chemical characteristics, rice yield and microbial processes in paddy fields. However, the knowledge about the impact of fly ash inputs alone or in combination with other organic amendments on soil methanotrophs number in paddy soils is almost lacking. We hypothesized that fly ash application at lower doses in paddy agriculture soil could be a potential amendment to elevate the paddy yields and methanotrophs number. Here we demonstrate the impact of fly ash and press mud inputs on number of methanotrophs, antioxidants, antioxidative enzymatic activities and paddy yields at agriculture farm. The impact of amendments was significant for methanotrophs number, heavy metal concentration, antioxidant contents, antioxidant enzymatic activities and paddy yields. A negative correlation was existed between higher doses of fly ash-treatments and methanotrophs number (R(2)=0.833). The content of antioxidants and enzymatic activities in leaves of higher doses fly ash-treated rice plants increased in response to stresses due to heavy metal toxicity, which was negatively correlated with rice grain yield (R(2)=0.944) and paddy straw yield (R(2)=0.934). A positive correlation was noted between heavy metals concentrations and different antioxidant and enzymatic activities across different fly ash treated plots.The data of this study indicate that heavy metal toxicity of fly ash may cause oxidative stress in the paddy crop and the antioxidants and related enzymes could play a defensive role against phytotoxic damages. We concluded that fly ash at lower doses with press mud seems to offer the potential amendments to improving soil methanotrophs population and paddy crop yields for the nutrient poor agriculture soils.
有报道称，应用粉煤灰、堆肥和压泥或它们的组合可以改善植物生长、土壤微生物群落等。此外，粉煤灰与农家肥或其他有机改良剂结合使用可以改善土壤理化特性、水稻产量和稻田微生物过程。然而，关于粉煤灰单独或与其他有机改良剂结合使用对稻田土壤甲烷氧化菌数量的影响的知识几乎没有。我们假设在稻田农业土壤中低剂量应用粉煤灰可能是一种潜在的改良剂，可以提高水稻产量和甲烷氧化菌数量。在这里，我们展示了粉煤灰和压泥输入对农业农田甲烷氧化菌数量、抗氧化剂、抗氧化酶活性和水稻产量的影响。改良剂对甲烷氧化菌数量、重金属浓度、抗氧化剂含量、抗氧化酶活性和水稻产量的影响显著。更高剂量的粉煤灰处理与甲烷氧化菌数量之间存在负相关关系（R²=0.833）。由于重金属毒性，高剂量粉煤灰处理水稻叶片中的抗氧化剂和酶活性增加，这与水稻籽粒产量（R²=0.944）和水稻秸秆产量（R²=0.934）呈负相关。不同粉煤灰处理区之间重金属浓度与不同抗氧化剂和酶活性之间存在正相关关系。本研究的数据表明，粉煤灰的重金属毒性可能会导致稻田作物发生氧化应激，抗氧化剂和相关酶可能在抵御植物毒性损伤方面发挥防御作用。我们得出结论，低剂量的粉煤灰与压泥似乎可以作为改良剂，为养分贫瘠的农业土壤提高土壤甲烷氧化菌种群和水稻作物产量提供潜力。
