Effects of Long-term K Fertilizer Application on the Crop Yield and K Distribution of Soil Aggregates in a Paddy-Upland Rotation System

• 作者: Chen Fowen He Junfeng Hu Yitao Huang Shuai Li Jifu Song Meifang Zou Jialong
• 来源期刊: 气象与环境研究:英文版
• 学科: 地球科学
• 关键词: Paddy-upland rotation POTASSIUM (K) FERTILIZER Yield Soil AGGREGATE Available K content
• 年，卷（期）: 2019,（1）
• 页码范围: 64-69
• 页数: 6页
• 分类号: P

摘要

[Objective] A long-term paddy-upland experiment was conducted to evaluate the effects of the recommended amount of potassium (K) fertilizer on crop yield, distribution of soil aggregate, and soil available K content. It was mainly to ascertain the distribution of K in the soil aggregate components in the paddy-upland rotation system, and then to provide theoretical basis for soil structure improvement, K pool management, and reasonable application of K fertilizer.[Method] There were 2 treatments selected, namely, NP (-K) treatment and NPK (+K) treatment in this study. Then the effects of K fertilizer application on the yield, available K content, and aggregate distribution in the middle rice-winter rape rotation system were analyzed.[Result] The results showed that the output of the crop rotation was affected by the year and fertilization. Compared with NP (-K), the average yield increases of rice and winter rape after application of K fertilizer were 0.51 and 0.33 t/hm 2, with the increments of 7.5% and 14.1% respectively. The long-term application of K fertilizer (7 a) had no significant effects on the distribution of soil aggregates but could significantly increase the water-soluble K content and available K content at depths of 20-30 and 30-40 cm, and available K content of aggregates in each particle size. In addition, the balance of available K at the 10-20 and 30-40 cm of soil layers was the most significant through calculation of surplus-deficit value of available K in agglomerates of different soil layers.[Conclusion] Compared with the initial available K content in the farmland in 2011, the current K fertilizer application could lead to that farmland K content continues to decline. Therefore, we should pay attention to straw returned and supplement of organic K fertilizer, to maintain crop rotation system s productivity and soil K balance.