Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611, USA.
Chemosphere. 2012 Nov;89(11):1467-71. doi: 10.1016/j.chemosphere.2012.06.002. Epub 2012 Jul 2.
When applied to soils, it is unclear whether and how biochar can affect soil nutrients. This has implications both to the availability of nutrients to plants or microbes, as well as to the question of whether biochar soil amendment may enhance or reduce the leaching of nutrients. In this work, a range of laboratory experiments were conducted to determine the effect of biochar amendment on sorption and leaching of nitrate, ammonium, and phosphate in a sandy soil. A total of thirteen biochars were tested in laboratory sorption experiments and most of them showed little/no ability to sorb nitrate or phosphate. However, nine biochars could remove ammonium from aqueous solution. Biochars made from Brazilian pepperwood and peanut hull at 600°C (PH600 and BP600, respectively) were used in a column leaching experiment to assess their ability to hold nutrients in a sandy soil. The BP600 biochar effectively reduced the total amount of nitrate, ammonium, and phosphate in the leachates by 34.0%, 34.7%, and 20.6%, respectively, relative to the soil alone. The PH600 biochar also reduced the leaching of nitrate and ammonium by 34% and 14%, respectively, but caused additional phosphate release from the soil columns. These results indicate that the effect of biochar on the leaching of agricultural nutrients in soils is not uniform and varies by biochar and nutrient type. Therefore, the nutrient sorption characteristics of a biochar should be studied prior to its use in a particular soil amendment project.
当应用于土壤时，生物炭是否以及如何影响土壤养分还不清楚。这不仅关系到养分对植物或微生物的有效性，还关系到生物炭土壤改良是否会增强或减少养分淋失的问题。在这项工作中，进行了一系列实验室实验，以确定生物炭改良对沙质土壤中硝酸盐、铵和磷酸盐吸附和淋失的影响。在实验室吸附实验中测试了总共 13 种生物炭，其中大多数对硝酸盐或磷酸盐的吸附能力很小/没有。然而，有 9 种生物炭可以从水溶液中去除铵。巴西胡椒木和花生壳在 600°C 下制成的生物炭（分别为 PH600 和 BP600）用于柱淋滤实验，以评估它们在沙质土壤中保持养分的能力。BP600 生物炭有效地将淋出液中的硝酸盐、铵和磷酸盐的总量分别减少了 34.0%、34.7%和 20.6%，而单独使用土壤则没有这种效果。PH600 生物炭也减少了硝酸盐和铵的淋失，分别减少了 34%和 14%，但导致土壤柱中额外的磷酸盐释放。这些结果表明，生物炭对土壤中农业养分淋失的影响并不均匀，并且因生物炭和养分类型而异。因此，在将生物炭用于特定的土壤改良项目之前，应该研究其对养分的吸附特性。
