Combined effect of intercrop cultivation and method of fertilization on mineral nitrogen leaching: Lysimetric experiment

Under the term of mixed culture or intercrop, we understand the cultivation of two different crops at same field simultaneously, in particular mixture of leguminous and non-leguminous crops. The need to cultivate these crops for improving soil fertility and sustainability is often neglected, but positive influence of legumes in crop rotation is widely recognized. Legumes have always been important crops, which have represented a source of food for humans, feed for animals and atmospheric nitrogen for soil. At present the importance of legumes is ignored, despite the fact that the cultivation of these plants brings a lot of benefits. The aim of this study is to describe the influence of intercrop cultivation and method of fertilization on leaching of mineral nitrogen from arable soil. This effect was tested by lysimetric experiment. Six variants (C1 a C2, A1 - A4) of the experiment were prepared, each one was prepared in three repetitions. These variants were divided into two groups. First group consists of two variants: C1 (Winter Wheat - Sole crops, control without addition of fertilizers) and C2 (Winter Wheat - Sole crops, 140 kg of N per hectare and year were applied here). Second group consists of four variants A1 - A4, mixed culture of Winter Wheat (Triticum aestivum) and White Clover (Trifolium repens) were cultivated here. These variants were fertilized by mineral and organic fertilizers. Significant differences (ANOVA; P<0.05) in leaching of mineral nitrogen were found between variants with intercrop (White Clover; A1-A4) and variants without (C1-C2). The significant lowest values were always found in variant A2 with intercrop. Based on these results we conclude that cultivation of intercrop/mixed culture represents new opportunity to mitigate the negative influences of extensive agriculture - leaching of mineral nitrogen.