【作者】 王丽英； 翟彩霞； 张彦才； 陈丽莉； 李若楠； 陈清；

【Author】 Wang Liying Zhai Caixia Zhang Yancai Chen Lili Li Ruonan Chen Qing (1 Institute of Agricultural and resource environment,Hebei Academy of Agricultural and Forestry sciences,Shijiazhuang,050051) (2 College of resource and environment,China Agricultural University,Beijing,100193)

【机构】 河北省农林科学院农业资源环境研究所； 中国农业大学资源与环境学院；

【摘要】 过量灌溉和氮肥投入是导致设施番茄氮素淋洗损失、氮肥利用率低的主要原因。氮素淋洗是氮素投入、植物吸收和土壤保持的综合结果,控制水分淋洗或减少硝态氮淋洗是控制氮素淋洗的有效途径。生物炭是指由有机废弃物经过不完全燃烧产生的一种多孔炭,比表面发达,吸附性强,对土壤水分和养分离子具有吸附和保持,特别是对NH₄⁺有很强的吸附作用。硝化抑制剂（3,4-dimethylpyrazole phosphate,DMPP）能有效铵态氮的氨氧化过程,使铵态氮肥保持在土壤中,减少硝态氮淋洗。本文采用微型渗漏计装置,在设施番茄原位模拟条件下,试验设置对照（NN）、硫酸铵（SA）、硫酸铵+DMPP（SA+DMPP）、硝酸钾（NN）、对照+生物炭（NN+BC）、硫酸铵+生物炭（NA+BC）、硫酸铵+DMPP+生物炭（NA+DMPP+BC）、硝酸钾+生物炭（NN+BC）8个处理,4次重复。生物炭添加量为土壤的8%（w/w）,DMPP添加量为施氮量的1%。研究生物炭及氮素形态对设施番茄生育期5次灌溉的淋洗液体积、硝态氮和铵态氮淋洗量、番茄氮素吸收、收获后根区土壤无机氮残留量和土壤缓冲性的影响结果表明,生物炭多孔的物理特性显著减少番茄生育期淋洗液体积19.9%,增加土壤水分保持能力;生物炭显著提高了番茄根区土壤的阳离子交换量（CEC）,但对土壤pH值的影响差异不显著;生物炭显著减少各处理的硝态氮淋洗量,平均比例为22.6%,铵态氮肥（AN）或添加硝化抑制剂的稳定性铵态氮肥（SA+DMPP）比硝态氮肥减少硝态氮淋洗量10.6%～33.9%;生物炭提高了铵态氮（AN）和硝态氮（NN）处理的番茄氮素吸收量,但降低了稳定性铵态氮（AN+DMPP）处理的番茄氮素吸收量;添加DMPP提高了番茄氮素吸收量21.2%～32.4%;添加生物炭降低了番茄收获后土壤无机氮素残留量,降低了氮素淋洗的风险;但硝化抑制剂对收获土壤硝态氮和铵态氮含量影响没有显著差异,而且生物炭与硝化抑制剂配合施用没有表现出叠加效应。综合分析表明,生物炭通过提高土壤阳离子交换量和减少灌溉水淋洗量来减少氮素淋洗、提高土壤氮素保持能力和番茄氮素吸收利用,而硝化抑制剂通过抑制氨氧化过程保持土壤的铵态氮含量。更多还原

【Abstract】 Excessive irrigation and nitrogen fertilizer input was the main reasons for nitrogen(N) leaching loss and low nitrogen use efficiency in greenhouse vegetable production.The result of N leaching was the combined result of N input,N uptake by vegetable and soil N retention capacity.So the effective management of reducing N leaching was control of water leaching or N retention capacity of soil.Biochar was a kind of porous carbon produced by incomplete combustion with organic waste(wood,straw or manure).Biochar’s surface is very large and can absorb water and nutrient from the soil,especially with the strong absorption for ammonium ion.The nitrification inhibitor(3,4-dimethylpyrazole phosphate,DMPP) can effectively ammonium oxidation process to keep ammonium-N in soil and reduce nitrate leaching. The in-situ incubation experiment with micro-lysimeter was conducted to examine the effect of biochar and N form on the soil buffer capacity and nitrogen leaching in greenhouse tomato.Eight treatments with four replicates randomly by two factors of biochar and N form were set up.The treatment was as the control(NN),ammonium sulfate(SA),ammonium sulfate with DMPP(SA+DMPP),potassium nitrate(NN),control with addition of biochar(NN+BC),ammonium sulfate with addition of biochar (NA+BC),ammonium sulfate with DMPP and biochar(NA+DMPP+BC),potassium nitrate with addition of biochar(NN+BC).The nitrogen application rate for N supply treatment was 200 kg N/ha for the basal fertilizer without top-dressing.The ratio of biochar addition was 8%(w/w) of the surface soil at 15cm depth and the ratio of DMPP was 1%of nitrogen amount from fertilizer. The total volume of irrigation water leaching for 5 times irrigation,nitrate-N and ammonium-N leaching,N uptake by tomato,inorganic nitrogen content,soil cation exchange capacity and pH of the post-harvest soil were examined.The result showed that the biochar with porous physical characteristics significantly reduced volume of irrigation water by 19.9%and increased soil moisture retention capacity. The cation exchange capacity(CEC) of the root zone soil was improved significantly with the addition of biochar,but the soil pH value was not affected significantly with biochar.The amount of nitrate leaching in all treatments was decreased with addition of biochar significantly and the reduction ratio was 22.6% averagely.Ammonium nitrogen(AN),or the stability of the ammonium nitrogen fertilizer with nitrification inhibitor(SA+DMPP in) could decrease nitrate leaching by 10.6%to 33.9%than the nitrate nitrogen fertilizer(NN);The N uptake by tomato was increased with biochar addition in the treatment of ammonium nitrogen(AN) and nitrate(NN),but decreased in the treatment stabilized ammonium nitrogen fertilizer (AN+DMPP);The N uptake by tomato with DMPP treatment was increased by 21.2%to 32.4%than NA and NN treatment.Added biochar could decrease soil nitrogen residual after tomato harvest and reduce the risk of nitrogen leaching.But the soil nitrate and ammonium nitrogen with the treatment of biochar didn’t change significantly.It was interesting that no additive effect of biochar and nitrification inhibitor was shown for soil nitrogen residual and N leaching. In summary,biochar can not only reduce N leaching,but also keep high mineral N retention in soil and N uptake by tomato,which might be the mechanism of the cation exchange capacity of the root zone soil increased and water retention capacity for biochar.The nitrification inhibitor DMPP can reduce Nitrate-N leaching and keep ammonium nitrogen in the soil,which might be the mechanism of inhabitation of ammonium oxidation process.更多还原