ISSN 1392-3196 / e-ISSN 2335-8947
Zemdirbyste-Agriculture, vol. 103, No. 1 (2016), p. 3–10
The effect of alternative cropping systems on the changes of the main nutritional elements in the soil
Laura MASILIONYTĖ, Stanislava MAIKŠTĖNIENĖ
Experiments were conducted at Joniškėlis Experimental Station of the Lithuanian Research Centre for Agriculture and Forestry in 2006–2013, on an Endocalcari-Endohypogleyic Cambisol (CMg-n-w-can), which is characterised by low phosphorus and high potassium contents with low (<2.0) and moderate (>2.1) humus content. The research was carried out in the crop rotation’s grass-cereal sequence: perennial grasses (grown as green manure) → winter wheat. The aim of experiments is to determine the changes of biogenic soil elements in the organic cropping systems by using farmyard manure and aftermath of red clover for green manure or their combinations for winter wheat fertilization, and in sustainable cropping systems – by replenishing the amount of nutritional elements with mineral fertilizers. The NPK balance was negative in the organic cropping system in the soil with both low and moderate levels of soil humus when only green manure had been used as fertilizer for winter wheat. The NP balance was strongly positive and K was significantly in excess in the organic cropping system when the green manure had been used in combination with 40 Mg ha-1 of farmyard manure. A marked reduction in the available phosphorus content in the soil with different humus levels was established when green manure or 40 Mg ha-1 of farmyard manure or their combinations had been applied. Also, potassium levels increased in the organic cropping system where green or farmyard manure had been applied. When 40 Mg ha-1 of farmyard manure and N30 mineral fertilizer had been used in the sustainable cropping system to promote straw mineralization, the nitrogen balance in the soil with the low humus content was slightly positive, but in the soil with moderate humus content it was strongly negative; in the soil of both humus levels phosphorus balance was slightly positive and potassium balance was significantly excessive. In the both soils with low and moderate humus content, in the sustainable cropping systems that had used the perennial grass aftermath as green manure with minimum rates of mineral fertilizer N30P60K60, N balance was negative, P – marginally positive. In the soil with low humus content K value was positive, in the soil with moderate humus content – marginally negative. In the sustainable cropping system, where perennial grass aftermath for green manure and N30P60K60 had been used for winter wheat during two 4-field crop rotations the available phosphorus and potassium quantity in the soil low and moderate in humus status showed a trend towards decreasing.
Key words: green and farmyard manure, mobile P2O5 and K2O, nutrient balance, organic and sustainable cropping systems.
Full text: 103_1_str1.pdf