Effects of Long-Term Fertilization on Organic Carbon and Nitrogen Dynamics in a Vertisol in Eastern China

Abstract

Mineral fertilizers and organic amendment can affect the various soil organic matter (SOM) pools and the distribution of organic carbon (OC) and nitrogen (N) in these pools. It is unknown how OC and N are distributed in different SOM pools under different long-term fertilization regimes. Therefore, this study aimed to examine the effects on OC and N concentrations in various SOM pools after 33 years of application of chemical fertilizer and organic amendment in Anhui Province in the Huang-Huai-Hai Plain, eastern China. This long-term experiment consisted of five fertilization treatments measuring changes in the OC and N concentrations in the soils and different SOM fractions of each experiment plot. Organic amendment increased the OC and N concentrations in the mineral-associated fraction, the coarse mineral-associated fraction and the aggregates compared with the values obtained without fertilizer application. Mineral fertilizer application alone increased the abovementioned indexes, but this increase was small. There was a small but significant increase in the OC and N concentrations in the free particulate fraction, and the change in magnitude had no obvious effect on the total OC (TOC) and total N (TN) concentrations in soils. More than 80% of the water-stable aggregate-associated C was stored in macroaggregates >2 mm in size. More than 60% of the TOC and TN accumulated within mineral associations in the soil, and organic amendment increased this proportion to 80%. These results suggest that the OC in Vertisols is dominated by mineral-associated OC and that the effect of organic amendment on mineral-associated OC is obvious.

Long Term Effects of Integrated Plant Nutrition System on Rice Yield, Nitrogen Dynamics and Biochemical Properties in Soil of Rice-rice Cropping System

“…Previous studies showed that combined application of manure and fertilizer increased soil TOC [61,67,68]. Similar result was also found in our study where higher soil TOC content was found with PM and CD amended soil.…”

“…Previous studies reveled that combined application of different organic matter and chemical fertilizer for long term significantly increased soil total N compared to only chemical fertilizer [61,62,63]. The higher N content in the top soil layer might be due to higher microbial activity which favors the availability of nutrient like N [43].…”

Incidence of Heavy Metals in the Application of Fertilizers to Crops (Wheat and Rice), a Fish (Common carp) Pond and a Human Health Risk Assessment

“…With the use of an inductively coupled plasma atomic emission spectrometer "ICP-AES, PerkinElmer, Optima 5300DV", the total and available concentrations of Cr, Pb and Mn were determined, whereas the concentration of Cd in the soil samples was analyzed using inductively coupled plasma mass spectrometry "ICP-MS, PerkinElmer SCIEX, Elan 9000". The properties of the soil, including soil organic matter (SOM), pH, Clay, EC (electrical conductivity) and CEC (cation exchange capacity), were analyzed following the procedure of Li et al [26]. The details of soil properties are given in Table 2.…”

Manejo nutricional integrado: herramienta clave para la agricultura sostenible

“…En rotaciones trigo-soja y trigo-maíz bajo MNI durante nueve años, el CO y el N del suelo tuvieron aumentos de entre 14 y 37%, esto gracias a que el C y N de los AOs se almacenan en fracciones recalcitrantes asociadas a los minerales del suelo (Li et al, 2018b). Con 46 años de MNI en el sistema maíz-trigo se incrementaron el CBM, RBS, MC y cociente microbiano, en comparación con la FM (Kaur et al, 2019).…”