摘要
研究甘肃河西半干旱区不同氮磷配施下棉田土壤有机质、土壤全氮、碱解氮含量及其相关性特点,为该区土壤有机质作为土壤氮素养分变化的早期预测指标提供依据。以石棉721号为试验材料,氮磷两因素随机区组设计大田试验,共设10处理,结合室内常规分析方法测定土壤有机质、土壤全氮、碱解氮含量。结果表明:土壤有机质含量与播前相比,5层土壤中有机质含量均降低。从施肥处理来看,5层土壤中N_3P_2处理有机质含量最高,且有机质含量N_2P_3>N_2P_2>N_2P_1>N_2P_0,但差异不显著;0～20cm、20～40cm土壤中有机质含量N_3P_2>N_2P_2>N_1P_2>N_0P_2。表明施用氮磷肥后,土壤有机质含量减少有所减缓。吐絮期各土层中,各施肥处理土壤全氮含量均高于对照(CK),各个土层中N_3P_2处理土壤全氮含量最高,表明增加氮素投入量均可提高土壤全氮含量。土壤碱解氮含量与播前相比,40～60cm土层中,除N_3P_2处理外,其余处理土壤碱解氮含量均比播前减小,其余4层土壤中各处理碱解氮含量均比播前减小;各个土层中以N_3P_2处理土壤碱解氮含量最高。除N_3P_2、N_2P_2K处理外,各个处理土壤有机质与土壤全氮均达到显著或极显著直线正相关;各个处理土壤有机质与土壤碱解氮无显著或极显著相关。因此土壤有机质可以作为指示土壤氮素状况的灵敏指标。
The contents of soil organic matter,total nitrogen and alkali-hydrolyzed nitrogen in cotton field and their correlation characteristics under different nitrogen and phosphorus combinations in Hexi semi-arid region of Gansu province were studied,to provide a basis for the early prediction of soil organic matter as an index of soil nitrogen nutrient change.Shimian 721 was used as the experimental material.Randomized block design with two factors of nitrogen and phosphorus and ten treatments was made under field conditions and routine analysis of soil organic matter,total nitrogen and alkali-hydrolyzed nitrogen was done at laboratory.The results showed that,compared with the soil before sowing,the content of organic matter in five layers of soil decreased.From the fertilization treatment,the organic matter content of N 3P 2 treatment was the highest in five layers of soil,and the organic matter content was N 2P 3>N 2P 2>N 2P 1>N”2P 0,but the difference was not significant,the organic matter content of 0-20 cm,20-40 cm soil was N 3P 2>N 2P 2>N 1P 2>N 0P 2.The results showed that the decrease of soil organic matter content was slowed down after applying nitrogen and phosphorus fertilizer.The total nitrogen content of all soil layers during flocculation stage was higher than that of CK,and N 3P 2 treatment had the highest total nitrogen content in all soil layers,which indicated that increasing nitrogen input could increase the total nitrogen content of soil.Compared with pre-sowing,in 40-60 cm soil layer,except for N 3P 2 treatment,the content of soil alkali-hydrolyzed nitrogen in other treatments decreased compared with pre-sowing,and the content of soil alkali-hydrolyzed nitrogen in the other four layers decreased compared with pre-sowing,and the content of soil reduced nitrogen in each layer was the highest in N 3P 2 treatment.Except for N 3P 2 and N 2P 2K treatments,soil organic matter and total nitrogen in all treatments had significant or extremely significant linear positive correlation,while soil organic matter in all treatments had no significant or extremely significant correlation with soil alkali-hydrolyzed nitrogen.Therefore,soil organic matter can be used as a sensitive indicator of soil nitrogen status.
作者
张学昕
ZHANG Xue-xin(College of Resources and Environmental Sciences,Gansu Agricultural University,Lanzhou 730070,China;Linxia State Agricultural Product Quality Safety Supervision and Management Station,Linxia 731100,China)
出处
《黑龙江农业科学》
2019年第1期37-44,共8页
Heilongjiang Agricultural Sciences
关键词
棉花
土壤有机质
土壤全氮
土壤碱解氮
cotton
soil organic matter
soil total nitrogen
soil available nitrogen
