不同水氮管理对日光温室番茄产量及土壤无机氮的影响

以传统水氮管理为对照,分别采用氮素实时监控技术对保护地番茄主要生育期进行氮素追施优化管理,同时结合小管出流的灌溉方式及夏季休闲季添加小麦秸秆-氰氨化钙的优化水氮管理处理并根据课题组同一地区多年的番茄氮素优化管理经验得出的推荐水氮管理处理,即将氮素追施量定为N 300 kg/hm2,在番茄第一、三、五穗果实膨大期各追施N100 kg/hm2,比较研究了不同水氮管理措施对保护地番茄产量及土壤无机氮的影响。结果表明:与传统水氮管理相比,在保证番茄产量的前提下,优化水氮管理和推荐水氮管理两季番茄分别减少了63.5%和50%的氮肥追施量,优化水氮管理处理两季番茄分别减少了44%和39%的灌溉用水。此外,优化水氮管理处理还显著提高了番茄全年的总产量,增产约10%。传统的氮素投入使番茄生育期内的土壤无机氮含量保持较高水平,试验结束时,传统水氮管理处理在0-180 cm各土层无机氮残留量均在N 200 kg/hm2以上,其0-180 cm土层无机氮残留总量已超过N 1 500 kg/hm2;而优化水氮管理和推荐水氮管理处理在改进水氮管理措施后,0-180 cm各土层无机氮残留量显著降低,仅为传统水氮管理的1/2,大幅度降低了土壤氮素的淋洗风险,减轻了由于不合理的水氮管理而对环境造成的影响。

Effects of Different Irrigation and Fertilization Strategies on the Yield and Inorganic N in Greenhouse Tomato System

Greenhouse tomato experiment was conducted in Shouguang,Shandong province in order to investigate the effects of different water and nitrogen strategies on fruit yield and soil inorganic nitrogen of greenhouse tomato.Compared with conventional water and nitrogen management(CWN),optimize water and nitrogen management(OWN) is real-time control of rootzone N management and related target values were used to optimize N sidedressing,and irrigation up to field capacity by employing with bubbler irrigation system during the growing season,and applied for Calcium Cyanamide mixed with wheat straw in summer-fallow,Recommended water and nitrogen management(RWN) is sidedressed 100 kg/hm2 at the duration of first,third and fifth fruit ear enlargement separately.The result showed that there were no significant differences on tomato fruit yield of the OWN and RWN with 36.5% and 50% of sidedressed N input in comparison with conventional water and nitrogen management during two season greenhouse tomato system,in addition,the OWN decreased the irrigation water by 44% and 39% in two growing seasons,but the fruit yield increased by 10% significantly.Conventional nitrogen input made the content of soil inorganic nitrogen kept in a high level during the tomato growing season;The residue of soil inorganic nitrogen above 200 kg/hm2 in every layer and the total residue of soil inorganic nitrogen more than 1500 kg/hm2 in 0-180 cm soil depth after harvesting.The residue of soil inorganic nitrogen is 1/2 of CWN after the OWN and RWN improved the water and nitrogen management,significantly reduced the risk of nitrogen leaching and the effects of unreasonable water and nitrogen management on environment.