水氮互作对设施番茄土壤氮平衡及氮素利用效率的影响研究

Study on the effects of water nitrogen interaction on soil nitrogen balance and nitrogen use efficiency of facility tomatoes

为了探明膜下滴灌条件下设施番茄的水肥优化管理,以设施番茄为研究对象,通过设置不同水肥处理,开展设施番茄水氮迁移转化规律试验研究,通过田间试验观测土壤硝态氮、铵态氮含量、植株吸氮量及温室气体排放等指标,分析土壤-作物系统氮素利用及分配。结果表明:氮素利用率随施氮量的增加而减小,氮肥偏生产力随氮素的输入量的增加而减小,氮肥偏生产力以W2N3最大(233 kg/kg),除CK处理外,W2N3氮盈余最小,不同处理氮素盈余占氮素总输入量的比例为49%~57%。设施番茄适宜土壤水分灌水下限为田间持水量的85%,适宜追肥量为171 kg/hm^(2),研究成果对指导北京地区设施蔬菜科学灌溉及施肥有重要的指导意义。

In order to investigate the water and fertilizer optimization management of facility tomatoes un⁃der subsurface drip irrigation conditions,this study took facility tomatoes as the research object and con⁃ducted experimental research on the water and nitrogen migration and transformation laws of facility toma⁃toes by setting different water and fertilizer treatments.The soil nitrate nitrogen,ammonium nitrogen con⁃tent,plant nitrogen uptake,greenhouse gas emissions,and other indicators were observed to analyze the nitrogen utilization and distribution in the soil crop system through field experiments.The results showed that the nitrogen utilization efficiency decreased with the increase of nitrogen application rate,and the ni⁃trogen partial productivity decreased with the increasing nitrogen input rate.The nitrogen partial produc⁃tivity of W2N3 was the highest(233 kg/kg),and the nitrogen surplus of W2N3 was the smallest except for CK treatment.The proportion of nitrogen surplus in different treatments to the total nitrogen input was 49%to 57%.The suitable lower limit for soil moisture irrigation of facility tomatoes was 85%of the field capacity,and the suitable amount of topdressing was 171 kg/hm^(2).The research results have important guiding significance for scientific irrigation and fertilization of facility vegetables in Beijing.