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潜水位的埋深(简称WTD);4个不随机地块的WTD值分别为0.61、0.76、0.91、1.07、1.22m。第1年和第2年的累积降雨量分别为406和634mm,花生(果荚)产量在3.5~5.5t/hm~2。如果WTD<0.91m,则花生产量>4t/hm~2。第1年,干物质累积量和花生产量与WTD呈负相关(R~2>0.37)。但是在第2年,由于雨量充沛,上述的植物特性与WTD之间也没有显著的相关关系。在较干旱年份,假定空气氮固定量提供了总氮累积量的45%,则氮的净累积量与WTD呈负的或较差的相关性(R~2=0.02)。而在湿润年份,土壤氮的净累积量的估算值达64~4kg/hm~2,净增氮与WTD的线性回归参数R~2为0.40,回归系数为-1.05。因此,潜水位的管理和排灌的调控可以为减少过剩氮和由此造成硝酸盐污染,以及稳定花生产量提供一种管理方法。
(WTD). The WTD values of four non-random plots were 0.61, 0.76, 0.91, 1.07 and 1.22 m respectively. The cumulative rainfalls in year 1 and year 2 were 406 and 634 mm, respectively. The yield of peanut (pod) was 3.5-5.5 t / hm 2. If WTD <0.91m, the yield of peanut> 4t / hm ~ 2. In the first year, dry matter accumulation and peanut production were negatively correlated with WTD (R ~ 2> 0.37). However, in the second year, due to abundant rainfall, there was no significant correlation between the above plant characteristics and WTD. In drier years, assuming a fixed amount of air nitrogen provides 45% of the total nitrogen accumulation, the net nitrogen accumulation correlates negative or poor with WTD (R ~ 2 = 0.02). In wet years, the estimated soil N accumulation reached 64 ~ 4kg / hm ~ 2. The linear regression equation R ~ 2 of net nitrogen addition to WTD was 0.40 and the regression coefficient was -1.05. Therefore, the management of phreatic water level and the regulation of irrigation and drainage can provide a management method for reducing excess nitrogen, resulting in nitrate pollution and stabilizing peanut production.