我国西瓜土壤氮素丰缺指标和推荐施氮量研究

Abundance-deficiency Index of Soil Nitrogen and Appropriate N Application Rates for Watermelon in China

为了确定我国西瓜科学施氮量,本研究采用“零散实验数据整合法”和“养分平衡-地力差减法新应用公式”,对我国西瓜土壤氮素丰缺指标和推荐施氮量进行了探究。结果表明,我国西瓜土壤碱解氮第1~8级丰缺指标依次为≥298、187~298、117~187、73~117、46~73、29~46、18~29 mg/kg和<18 mg/kg;土壤全氮第1~8级丰缺指标依次为≥7.0、3.5~7.0、1.7~3.5、0.9~1.7、0.5~0.9、0.2~0.5、0.1~0.2、<0.1 g/kg;土壤有机质第1~8级丰缺指标依次为≥65、32~65、16~32、8~16、4~8、2~4、1~2、<1 g/kg。当氮肥利用率为30%~50%,西瓜目标产量30~90 t/hm^(2)时,第1~8级土壤推荐施氮量分别为0、12~60、24~120、36~180、48~240、60~300、72~360、84~420 kg/hm^(2)。本研究初步建立了我国西瓜土壤氮素丰缺指标推荐的施肥系统,以期为我国西瓜测土施氮奠定基础。

To scientifically determine the nitrogen application rate for watermelon in China,the method of“scattered experimental data integration”and the method of“nutrient balance and target yield minus soil fertility yield”were employed to explore the abundance index(ALI)of soil alkaline hydrolysis nitrogen and organic matter and the recommended soil fertilizer application rates(RSFAR)for watermelon planting in China.The results showed that the ALI of soil alkaline hydrolysis nitrogen for watermelon planting in China from the first to the eighth level was≥298,187-298,117-187,73-117,46-73,29-46,18-29,18 mg/kg,respectively.The ALI of soil total hydrolysis nitrogen from the first to the eighth level was≥7.0,3.5-7.0,1.7-3.5,0.9-1.7,0.5-0.9,0.2-0.5,0.1-0.2 g/kg and<0.1 g/kg,respectively.The ALI of soil organic matter from the first to the eighth level was≥65,32-65,16-32,8-16,4-8,2-4,1-2 g/kg and<1 g/kg,respectively.When the N fertilizer use efficiency was 30%-50%and the target yield was 30-90 t/hm^(2),the range of the RSFAR of N for the first to the eighth level was 0,12-60,24-120,36-180,48-240,60-300,72-360,84-420 kg/hm^(2),respectively.The recommended fertilization system of N in China’s watermelon soil was established preliminarily,which could provide a scientific basis for watermelon soil testing and fertilization.