Water storage pit irrigation (WSPI) has been proven effective in improving the water use efficiency of fruit trees in Loess Plateau, but so far there are still no matching efficient fertilization management methods. A two-year experiment was conducted to explore the management strategy of fertilization under the consideration of apple production and environmental sustainability. N isotope tracer technique was used to study the distribution of labelled nitrogen in soil, leaf, root and fruit. Moreover, the yield in different fertilizer managements were observed to evaluate the apple production. The results showed that increasing the amount of fertilizer could increase the accumulation of fertilizer nitrogen in soil, but also increased the risk of nitrogen leaching. Under the same amount of fertilizer, split fertilization can effectively increase of fertilizer nitrogen in soil by a mean of 4.7 times. Further, N300 application with split fertilization effectively increased apple yield. The yield of N300II treatment was higher than other treatment by maximum 68.5%. In addition, the root system mainly absorbed the fertilizer nitrogen applied in the current year, and the fruit mainly absorbed the fertilizer nitrogen applied in the previous year, but there was no significant difference in the leaves.

中文翻译：

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黄土高原苹果园WSPI施肥管理对土壤氮素分布和氮素吸收的影响。

事实证明，储水坑灌溉（WSPI）可以有效提高黄土高原果树的水分利用效率，但到目前为止，还没有匹配的高效施肥管理方法。进行了为期两年的实验，在考虑苹果生产和环境可持续性的情况下探索了施肥的管理策略。氮同位素示踪技术用于研究标记氮在土壤，叶片，根和果实中的分布。此外，观察到不同肥料管理下的产量以评估苹果的产量。结果表明，增加肥料用量可以增加土壤中肥料氮的积累，但也增加了氮淋失的风险。在相同量的肥料下 分次施肥可以使土壤中的肥料氮有效增加4.7倍。此外，N300配合施肥可有效提高苹果产量。N300II处理的产率比其他处理高68.5％。此外，根系主要吸收了当年施用的肥料氮，而果实主要吸收了上一年施用的肥料氮，但是叶片之间没有显着差异。