生物炭对北京郊区砂土持水力和氮淋溶特性影响的土柱模拟研究

发布时间：2018-05-30 14:23

本文选题：生物炭 + 沙化　；参考：《农业环境科学学报》2017年09期

【摘要】：为探讨生物炭对北京郊区砂土持水力和氮素淋溶特性的影响,通过分层采集不同深度(0~90 cm)北京郊区沙化地土壤(砂土),模拟田间容重和含水量填装土柱,将生物炭分别按照炭土质量比0%、0.5%、1%、2%和4%施入0~20 cm土层,依据常规施氮肥量(0.56 t N·hm-2)和年平均降雨量(616.6 mm)施肥和滴灌,开展土柱淋溶试验。结果表明:在9次淋溶后,水和总氮的累积淋失量均随着生物炭添加量的增加而减小,与不加炭处理相比最高分别减小41.3%和22.7%。添加生物炭增加了0~20 cm土层总氮含量,最高显著增加158%(P0.05)。淋溶结束后加炭处理土柱土壤中的无机氮总量比不加炭处理高19.5%~91.9%。添加生物炭有利于减小可溶性有机碳的淋失,比不加炭处理最高减小22.8%。淋溶液pH值和电导率随生物炭添加量增加而增大。在9次淋溶过程中,生物炭添加量越大,0~20 cm土层土壤持水量越高。相关性分析表明,总氮淋失量与淋溶液淋失体积显著正相关(r=0.978,P0.01),而与淋溶液中的总氮浓度无正相关关系。生物炭主要通过提高京郊砂土的持水能力,减缓水和氮素向下淋溶的速度,从而减小水和氮素的淋溶损失,提高水肥利用率,降低污染地下水的风险。
[Abstract]:In order to study the effect of biochar on the hydraulic capacity and nitrogen leaching characteristics of sandy soil in Beijing suburb, soil (sand soil) in sandy land of Beijing suburb was collected by stratification of different depth (0 ~ 90 cm), and the soil column was filled with bulk density and water content in the field. The experiment of soil column leaching was carried out by applying 2% and 4% biochar into 0 ~ 20 cm soil layer according to the ratio of carbon to soil mass 0. 5% and 4%, respectively. The soil column leaching experiment was carried out according to the conventional nitrogen fertilizer amount of 0. 56 t N hm-2) and the annual average rainfall of 616. 6 mm). The results showed that the cumulative leaching loss of water and total nitrogen decreased with the increase of the amount of biochar after 9 times of leaching, and decreased by 41.3% and 22.7%, respectively, compared with the treatment without carbon. The addition of biochar increased the total nitrogen content in 0 ~ 20 cm soil layer, and increased the content of total nitrogen in the soil layer of 0 ~ 20 cm to a maximum of 158% P _ (0.05). The total amount of inorganic nitrogen in soil column treated with carbon after leaching was 19.5% higher than that without carbon treatment (91.9%). The addition of biochar can reduce the leaching loss of soluble organic carbon, which is 22. 8% lower than that of no carbon treatment. The pH value and conductivity of leaching solution increased with the increase of biochar content. In the process of 9 times leaching, the higher the amount of biochar was, the higher the soil water holding capacity was in the soil layer of 20 cm. The correlation analysis showed that the amount of total nitrogen leaching was positively correlated with the volume of leaching solution, but had no positive correlation with the concentration of total nitrogen in leaching solution. Biochar can reduce the leaching loss of water and nitrogen, increase the utilization rate of water and fertilizer, and reduce the risk of groundwater pollution by increasing the water holding capacity of sandy soil in Beijing suburb and slowing down the downward leaching rate of water and nitrogen.
【作者单位】：北京市农林科学院北京草业与环境研究发展中心;河北农业大学资源与环境科学学院;中国科学院南京土壤研究所;
【基金】：国家自然科学基金青年科学基金项目(41501336) 北京市优秀人才培养资助项目(2015000020060G141) 公益性行业(农业)科研专项(201503106) 北京市科技计划课题(D151100005915002)~~
【分类号】：S156.2

【相似文献】