The effects of long-term application of organic and inorganic fertilizers on soil and plant Nitrogen-Carbon contents

Abstract

Soil and crop management such as chemical fertilizer applications hurt the soil’s biological quality and productivity. The most well-known organic fertilizer such as animal manure, compost and mycorrhizal fungi are significantly contributing to soil organic carbon sink and consequently, organic fertilizers have a positive effect on the soil biological diversity and productivity. To increase soil carbon content, long-term organic fertilizer applications increase soil carbon budget hypothesis was tested under field conditions. The aim is to investigate the effects of different organic and inorganic fertilizer applications on the soil and wheat plant carbon and nitrogen content. A long-term field experiment was established in 1996 until the present time. In 2018, before cultivation control, Mineral fertilizer (NPK), Animal manure (25 ton ha-1), Compost (25 ton ha-1) and Compost+Mycorrhiza (10 ton ha-1) were applied. Adana-99 varieties of wheat seeds were sown. After harvest, soil and plant samples were taken and soil-plant carbon-nitrogen analyses were made. Results show that C % and N % contents of the plant seed, shoot, and root have higher concentrations than that of the control treatment. When the TC %, OC %, and N % contents of the soil at different depths (0-15 cm and 15-30 cm) and in the rhizosphere (R) and no rhizosphere (NR) area were examined, compost and animal manure treatments have higher content. At the rhizosphere area 0-15 cm depth the soil % OC, and % IC contents were statistically significant. The highest values of soil OC %, C: N and IC % contents at Rhizosphere 0-15 cm depth were obtained in animal manure with 2.94 %, 10.06, and 3.90 % respectively. Organic fertilizers application increased soil TC %, OC % and N% contents as well as contribute to the carbon and nitrogen budget. The results found support our hypothesis.