红壤坡地不同生态措施地下径流养分流失研究

Study on the Nutrition Loss in Subsurface Runoff under Different Ecological Measures on Red Soil Slope

利用大型土壤渗漏装置(Drainage Lysimeter)对百喜草覆盖、百喜草敷盖、裸露三种生态措施的地下径流养分流失问题进行了研究。结果表明:在试验期间这三种处理措施氨氮流失总量分别为992.64 mg,2 679.67 mg,258.84 mg;总氮流失总量为1 096.494 mg,3 108.376 mg,295.064 8 mg;总磷流失量为603.35 mg,3 109.45 mg,182.42 mg;养分随地下径流流失量敷盖最大、裸露对照最小,这和一般情况下地表径流养分流失有所不同;从流失过程可以看出这三个处理的地下径流养分流失和径流过程比较相似,符合"肥随水走"的水肥运动规律,当降雨过后地下径流变大,养分流失也增大;在整个过程中,氨氮随径流过程变化剧烈,而且随地下径流流失量大,总磷则相对平稳,而且流失量也小。

The nutrient loss in subsurface runoff was studied on red soil slope under different measures by using Drainage Lysimeter.The results show that the amount of ammonia nitrogen loss under three measures were 992.64 mg,2679.67 mg,258.84 mg;total nitrogen loss were 1096.494 mg,3108.376 mg,295.0648 mg;total phosphorus loss were 603.35 mg,3109.45 mg,182.42 mg.The nutriment loss in subsurface runoff was the highest under mulch and was the least under bareness.It was different from surface runoffs.It can be seen that the process of nutriment loss parallel the runoff process in accord with the law of nutriment movement follow water.The subsurface runoff is increasing after the rain,the nutriment loss increase too.The rangeability of ammonia nitrogen loss was large,and the rangeability of total phosphorus was relatively stable.