Potassium assessment of grain producing soils in North China

文献类型： 外文期刊

第一作者： Jiang, Lihua

作者： Jiang, Lihua;Liu, Zhaohui;Jin, Jiyun;Huang, Shaowen

作者机构：

关键词： Potassium budgets;Soil potassium;Utilization efficiency of K fertilizer;Yield effect of K fertilizer application

期刊名称：AGRICULTURE ECOSYSTEMS & ENVIRONMENT （ 影响因子：5.567； 五年影响因子：6.064 ）

ISSN：

年卷期：

页码：

收录情况： SCI

摘要： Agricultural land around the world is often potassium (K) deficient, and decreasing soil K availability is a global challenge for grain producers. In China, negative K budgets are ubiquitous and K depletion is accelerating. Previous studies have mainly focused on the effect of insufficient K fertilizer on single soil types and cropping systems but have not evaluated the effects of balanced fertilizer application on K budgets. In this study, soil K budgets of grain producing soils and the effects of K fertilizer application on crops under different cropping systems and soil types were evaluated from 1992 to 2006. Two treatments each at nine locations in North China were replicated four times, four plots received nitrogen (N) and phosphorus (P) fertilizer application exclusively, and the other four plots received N, P, and K fertilizer application. Basic soil properties, available K, slowly available K, crop rotations, crop K absorption, and yield were monitored and evaluated and K budgets and K use efficiencies were calculated. Average annual K absorption by crops with K fertilizer application was 230.2 kg ha(-1) K2O, and the average annual deficit was 46.8 kg ha(-1) K2O. Long-term application of K fertilizer increased available soil K on all nine sites by an average of 35.7 mg kg(-1). Annual K absorption by crops averaged 99.0 kg ha(-1) in the northeast region, 181.2 kg ha(-1) in the north-central region, and 220.9 kg ha(-1) in the northwest region. Annual K fertilizer use efficiency in the northeast (39.9%) and north-central (38.8%) regions were higher than in the northwest (17.8%). Correlations between annual K budgets and K use efficiency with fertilizer application, crop rotation, and soil type were weak. High spatial variability and low correlation between variables is a result of the complex mechanisms of K cycling. Research directions are proposed which would contribute to a better understanding of these mechanisms and processes and how they affect agronomic and economic objectives. (c) 2011 Elsevier B.V. All rights reserved.

分类号： S

  • 相关文献
作者其他论文 更多>>

微信小程序