生物炭对黄壤养分含量及氮磷淋失的影响

Effects of Biochar on the Nitrogen and Phosphorus Nutrients and Leaching in Yellow Soil

摘要: 黄壤是贵州省农业生产主要土壤类型，特殊的土地条件与丰富的降雨造成土壤养分淋失，而且会引起水体污染。生物炭可以用来改善土壤环境和控制养分的淋失。然而，生物炭对黄壤中氮磷养分淋失的影响仍不是很清楚。本文采用室内土柱模拟淋溶方法，设置添加0 kg/m² (B0)、2 kg/m² (B2)、4 kg/m² (B4)、6 kg/m² (B6) 4个水平生物炭，研究4个处理对土壤养分含量及淋溶液体积、总氮、总磷、 和 淋失的影响。结果表明：土壤添加生物炭后，土壤pH、全氮、全磷、速效氮和速效磷含量随着生物炭添加量的增大而增加；添加生物炭的处理减少了水分的流失，添加2 kg/m²、4 kg/m²、6 kg/m²三个水平生物炭处理的累计淋溶液体积分别比未添加处理减少了0.3%、1.5%、2.0%；同等施肥条件下，添加生物炭处理与未添加相比，均显著降低了土壤淋溶液里TP、TN、 、 的累积淋失量，但以2 kg/m²处理降低效果最好。综上，黄壤中添加生物炭能够改善土壤和有效减少土壤养分的流失，其中有一个最适宜的生物炭添加量实现TP、TN、 、 淋失控制达到良好效果。

Abstract: Yellow soil is the main soil type supporting agricultural production in Guizhou Province. Special Karst geological conditions and abundant rainfall in Guizhou Province cause soil nutrients intense leaching, and water pollution. Biochar can be used to improve soil environments and to control nutrient leaching. However, effects of biochar on nitrogen and phosphorus nutrients and leaching in yellow soil remain unclear. We used soil columns containing 0 kg/m² (B0), 2 kg/m² (B2), 4 kg/m² (B4) and 6 kg/m² (B6) biochar to simulate the nitrogen and phosphorus leaching at laboratory and tested total nitrogen, total phosphorus, and in leachate and soil nutrient contents in soils. The results showed that soil pH, total nitrogen, total phosphorus, available nitrogen and available phosphorus increased with the increasing of biochar addition. The addition of biochar resulted in the reduction of loss of water. Under the application of 2 kg/m², 4 kg/m², 6 kg/m² biochar to soils, the leachate volume decreased by 0.3%, 1.5% and 2.0% than those without adding biochar to soils, respectively. Under the same fertilization conditions, the addition of biochar significantly reduced TP, TN, and in leachate from soil columns than those without addition. The addition of 2 kg/m² biochar to soils was optimum. In general, applying bio-char into yellow soil can improve soils and effectively reduce the loss of soil nutrients, and there is the most suitable biochar additions to achieve the TP, TN, , leaching control.