Field balances and recycling rates of micronutrients with various fertilization treatments in Northeast China

Abstract

Due to their effects on human health, recent research in China has focused on the status of micronutrients in agro-ecosystems. In this study, we analyzed the concentrations of available micronutrients in cropping systems, their recycling rates in the feeding-composting cycle, and their field balances. Our results showed there were significant differences in the concentration of available micronutrients among treatments, with micronutrients found highest in the NPK ? M (recycled pig manure) treatment. The recovery ratio of feed stuffs and bedding materials by a feeding-composting cycle was 25%, which was lower than the residual ratio of organic material that was decomposed for 1 year. The recycling rate of Zn, whose concentration was the lowest compared with that of other elements, was about 80%, while the recycling rates of Fe, Mn and Cu were between 85 and 90%. Micronutrient inputs by mineral fertilizer were lower than those of manure. Outputs were determined by crop yield and significantly differed among the treatments. The micronutrient contents from atmospheric deposition were 28-68 and 4-11 times greater than mineral fertilizers and manure, respectively. The balances of micronutrients were positive in all treatments, while excesses were lower in the NPK and CK treatments compared to other treatments. Since the pool of micronutrients is large, it may take hundreds of years to alter the concentration of micronutrients after reclamation. The recycling of nutrients had a positive effect on the balance of soil micronutrients, but we observed no significant changes in total micronutrient concentrations after reclamation.

Maize Nutrient Accumulation and Partitioning in Response to Plant Density and Nitrogen Rate: II. Calcium, Magnesium, and Micronutrients

“…Grain Zn concentration was influenced neither by PD nor by N rate. A similar lack of N rate effect on grain Zn was documented by Bruns and Ebelhar (2006), Riedell et al (2009), and Yu et al (2011). Minor N rate effects on grain Ca but more significant N rate effects on grain Mg concentrations were reported by Feil et al (2005).…”

Long-Term Effects of Straw and Manure on Crop Micronutrient Nutrition under a Wheat-Maize Cropping System

“…As well as being similar among treatments, the maize grain concentrations of Fe, Mn, Cu, and Zn were similar to those found by Berenguer et al (2008), Li et al (2007), Yu et al (2011) and surveys of maize grown in the Hebei province of China (Jia et al, 2009). However, the Cu concentrations were clearly too low to meet the physiological requirements of ruminant animals (9-11 mg kg −1 ; McDowell, 2003), which is a source of concern since maize grain is commonly used for feeding animals in the study region.…”

“…Application of chemical NPK fertilizer alone resulted in negative balances of all four micronutrients. Yu et al (2011) found balances of the four elements to be positive under all treatments they considered in a single cropping system in northeast China. However, this was mainly due to high inputs through deposition (3.720, 1.112, 0.142, and 0.544 kg ha −1 a −1 of Fe, Mn, Cu, and Zn, respectively), while in the system we examined deposition was negligible (Table 4).…”

Nitrification inhibitors mitigate earthworm-induced N2O emission—a mesocosm study

“…Some characteristics of the tested soil were as follows: organic matter 20.9 g kg −1 , total N 1.13 g kg −1 , total P 0.44 g kg −1 , total K 16.4 g kg −1 , available P 10.6 mg kg −1 , available K 88.0 mg kg −1 , pH 6.5 (Yu et al 2011). Twokilogram air-dried soil was packed at approximately 1.25 g cm −3 bulk density, and the depth of the soil was about 11 cm in each jar.…”