宁南山区不同建设年限梯田土壤肥力变化规律研究

Study on Variation Law of Soil Fertility of Terraced Fields Built in Different Years in the South Mountainous Region of Ningxia

对国家农业综合开发水土保持项目宁夏项目区6个重点小流域坡改梯工程实施后不同建设年限的梯田土壤肥力进行了为期4年的定点跟踪监测研究,结果表明,坡改梯初期土壤肥力与修建前相比有所降低,经过3～5年的合理培肥和土壤肥力的逐步恢复,不同建设年限梯田土壤肥力的年度变化大体上呈现出逐渐提高的趋势,在梯田修建第5～7年土壤肥力各项指标达到最高,但修建第8年时土壤肥力出现了下降趋势。建议政府相关部门继续加大梯田建设力度,重视梯田修建后的培肥与改良,为宁南山区作物高产、稳产提供有力保障。

The paper conducted 4-year fixed point tracking and monitoring research on soil fertility of terraced fields built in different years after carrying out the project of terraced field construction from sloping land in the 6 key small watersheds of Ningxia project area of National Agricultural Comprehensive Development Project for Soil and Water Conservation.The outcomes show that the soil fertility of terraced field in the early days is somewhat decreased comparing with that of the before construction.After 3-5 year’s rational fertilization,soil fertility gradual recovered,and the annual change of the soil fertility of terraced fields built in different years shows an increasing trend.Each index of soil fertility of the terraced fields built for 5-7 years reaches the maximum and it shows a decrease trend in the 8^th year of building.It suggests that related government departments should continue to intensify terrace building efforts,pay attention to fertilization and improvement after terracing and provide strong security for high and stable yield of crops of the south mountainous region of Ningxia.