高海拔区核桃土壤平衡施肥技术研究

Study on Balanced Fertilization Technology of Walnut Soil in High Altitude Area

摘要: 本文连续2年(2018~2019)以8a生“清香”核桃为研究对象，研究了不同氮、磷、钾配比对产量及生长发育的影响，以期为制定高海拔区核桃平衡施肥技术提供理论依据。结果表明，施肥处理效果高于不施氮肥处理；在磷钾肥相同的条件下，随着施氮量的增加，其产量、施肥效益、叶面积、SPAD值和养分含量呈抛物线模型，当N2水平时为峰值，而胸径、侧枝和树高呈线形正增长模型；在氮磷钾合理配施的条件下，过量施磷或钾肥，施肥效益明显降低，树体营养失衡，影响树体各器官及叶片的正常生长，前者提高侧枝的生长累积量，后者促进主干生长。高海拔区核桃合理的施肥量为氮0.6 kg + 磷0.4 kg + 钾0.3 kg，能协调树体生长发育，实现高产高效的目的，在该区应大面积推广应用。

Abstract: Taking 8a raw “qingxiang” walnuts as the research object for 2 consecutive years (2018-2019), the effects of different nitrogen, phosphorus, and potassium ratios on yield and growth were studied, with a view to formulating a balanced fertilization technology for walnuts in high altitude areas to provide a theory. The results showed that the fertilization treatment effect was higher than that without nitrogen fertilizer treatment. Under the same conditions of phosphorus and potassium fertilizer, the yield, fertilization benefit, leaf area, SPAD value, and nutrient content showed a parabolic model with the increase of nitrogen application rate. It is a peak value at the horizontal N2 level, and the DBH, side branches, and tree height show a linear positive growth model. Under the condition of reasonable combination of nitrogen, phosphorus, and potassium, excessive ap-plication of phosphorus or potassium fertilizer will significantly reduce the benefit of fertilizer application; the nutritional imbalance of the tree body will affect tree organs and the normal growth of the leaves. The former increases the accumulation of lateral branches, and the latter promotes the growth of the trunk. The reasonable fertilization rate for walnuts in high altitude areas is 0.6 kg of nitrogen + 0.4 kg of phosphorus + 0.3 kg of potassium, which can coordinate the growth and development of the tree body, achieve the purpose of high yield and efficiency, and should be widely applied in this area.