植物的氮稳定同位素可用于验证肥料来源,但是茶(山茶)植物的肥料吸收模式尚不清楚。在这项研究中,盆栽茶树用三种有机肥料(OFs)处理,尿素,和一个控制。茶叶从顶部取样七个月,中间,并分析了植物的δ15N和氮含量,以及相应的土壤样本。用菜籽饼OF处理的顶级茶叶具有最高的δ15N值(高达6.6),接着是鸡粪,牛粪,控制,和尿素肥料(6.5,4.1,2.2个,和0.6,分别)。用牛粪处理的土壤具有最高的δ15N值(6.0分),接着是鸡粪,油菜籽蛋糕,control,和尿素肥料(4.8,4.0,2.5,和1.9,分别)。菜籽饼施肥的茶叶在秋季仅表现出轻微的δ15N值变化,但在早春显著增加,然后在春末下降。与缓释肥料的交付一致。同时,顶部的δ15N值,中间,用菜籽饼处理过的茶树基叶在早春一直较高,在秋季和晚春较低,分别。尿素和对照样品的茶叶δ15N值比菜籽饼处理的茶低,并且随着时间的推移,茶叶δ15N值普遍降低。结果阐明了用不同肥料类型处理的茶叶的时间氮模式和同位素组成,并确保δ15N茶叶值可用于鉴定不同收获期和叶片位置的有机肥方法。基于盆栽实验的当前结果需要在开阔的农业土壤中进一步探索各种潜在的肥料对茶树中氮同位素比变化的影响。
The nitrogen-stable isotopes of plants can be used to verify the source of fertilizers, but the fertilizer uptake patterns in tea (Camellia sinensis) plants are unclear. In this study, potted tea plants were treated with three types of organic fertilizers (OFs), urea, and a control. The tea leaves were sampled over seven months from the top, middle, and base of the plants and analyzed for the δ15N and nitrogen content, along with the corresponding soil samples. The top tea leaves treated with the rapeseed cake OF had the highest δ15N values (up to 6.6‱), followed by the chicken manure, the cow manure, the control, and the urea fertilizer (6.5‱, 4.1‱, 2.2‱, and 0.6‱, respectively). The soil treated with cow manure had the highest δ15N values (6.0‱), followed by the chicken manure, rapeseed cake, control, and urea fertilizer (4.8‱, 4.0‱, 2.5‱, and 1.9‱, respectively). The tea leaves fertilized with rapeseed cake showed only slight δ15N value changes in autumn but increased significantly in early spring and then decreased in late spring, consistent with the delivery of a slow-release fertilizer. Meanwhile, the δ15N values of the top, middle, and basal leaves from the tea plants treated with the rapeseed cake treatment were consistently higher in early spring and lower in autumn and late spring, respectively. The urea and control samples had lower tea leaf δ15N values than the rapeseed cake-treated tea and showed a generalized decrease in the tea leaf δ15N values over time. The results clarify the temporal nitrogen patterns and isotope compositions of tea leaves treated with different fertilizer types and ensure that the δ15N tea leaf values can be used to authenticate the organic fertilizer methods across different harvest periods and leaf locations. The present results based on a pot experiment require further exploration in open agricultural soils in terms of the various potential fertilizer effects on the different variations of nitrogen isotope ratios in tea plants.