CAJ | 학술논문

采用~(15)N示踪法和差减法结合,对浙江嘉兴市3种氮素水平菜田-菜稻轮作田、低龄保护地(3 a)和高龄保护地(10 a)的氮肥利用、损失等进行了研究.结果表明,不施肥处理随着土壤氮素水平的增加油菜生物量呈增加趋势.但干重先增加后降低,油菜含氮量随土壤氮素含量的增加和氮肥的施用量呈增加趋势.根据差减法计算的氮肥利用率随土壤氮素含量的增加呈明显降低趋势,相反损失呈明显增加趋势.差减法氮肥利用率为2.3%～14.3%,损失率为23.9%～71.8%.示踪法利用率呈先增加后降低趋势,为14.6%～29.4%.示踪法损失率随土壤氮素水平的提高呈明显增加趋势,为34.5%～61.0%.示踪法和差减法总体趋势一致.
채용~(15)N시종법화차감법결합,대절강가흥시3충담소수평채전-채도륜작전、저령보호지(3 a)화고령보호지(10 a)적담비이용、손실등진행료연구.결과표명,불시비처리수착토양담소수평적증가유채생물량정증가추세.단간중선증가후강저,유채함담량수토양담소함량적증가화담비적시용량정증가추세.근거차감법계산적담비이용솔수토양담소함량적증가정명현강저추세,상반손실정명현증가추세.차감법담비이용솔위2.3%～14.3%,손실솔위23.9%～71.8%.시종법이용솔정선증가후강저추세,위14.6%～29.4%.시종법손실솔수토양담소수평적제고정명현증가추세,위34.5%～61.0%.시종법화차감법총체추세일치.
The fates of nitrogen(N) fertilizer (urea) in three types of vegetable fields with different fertility (mainly nitrogen) levels, including low N level (vegetable and rice rotation field), middle N level (new protected vegetable cultivation field), and high N level (old protected vegetable cultivation field) were studied with the methods of 15N isotope technique together with different calculation methods in Jiaxing city, Zhejiang province. The results showed that cole fresh yield was increased with soil nitrogen (N) level of three fields with no N application, but the dry yield was increased first and then decreased. The N contents of cole were all increased with soil N level and fertilization. N use efficiency (NUE) calculated by different methods presented downtrend with soil N level, ranging from 2.3% to 14.3%. However, the N loss rates (NLR) increased with soil N level. Tracer method and subtration method gave similar NUE and NLR.