Effects of rare-earth fertilizers on the emission of nitrous oxide from agricultural soils in China

Abstract

Rare-earth fertilizers have long been used in agriculture in China. The consequences of these applications are of more recent concern. In our study, an experiment was carried out to identify the effects of applying rare-earth fertilizers on emission of nitrous oxide from paddy and dryland soils in northern China. Normal dosage of rare-earth fertilizers only, normal dosage of urea only, normal dosage of urea plus rare-earth fertilizers, and a normal urea application plus a 10-fold increase in the dosage of rare-earth fertilizers were applied to the soils in pots, prepared for our experiment. A static closedchamber technique was used to measure nitrous oxide emission flux from the soil in the pots before and after fertilization during the experiment. The results show that the application of only rare-earth fertilizers did not have any visible effect on the emission of nitrous oxide from both paddy and dryland soils. Applying a normal dosage rare-earth fertilizers plus urea led to greater emission of nitrous oxide from the soils than only applying the normal dosage of urea. When a 10-fold increase of rare-earth fertilizers dosage was added to a normal dosage of urea, the emission of nitrous oxide from the soils increased even further. We speculate that the application of rare-earth fertilizers leads to an increase of available NH 4 + -N from urea hydrolysis and activate bacteria and enzymes in nitrification and de-nitrification. r

Strategic Role of Nanotechnology in Fertilizers: Potential and Limitations

“…A 2004 patent describes nanoiron oxide mixed with peat and CaCO 3 , leading to improved crop quality (Wu 2004a). Rare-earth element (REE) fertilizers have been applied as microelement fertilizers in Chinese agriculture since the 1980s (Wang et al 2008b). REE Inset: dramatic increase in root growth of peanut plant after nano-ZnO treatment (right: 1,000 ppm) after 110 days in comparison to bulk zinc (left: 1,000 ppm) over the same time period (Prasad et al 2012).…”

Rare earth elements concentrations and speciation in rainwater from Guiyang, an acid rain impacted zone of Southwest China

“…In East Asia, especially in China, REE fertilizer has been widely used since the 1990s. Approximately 1.3×10 6 kg of REEs is consumed on agricultural land every year (Pang et al, 2002;Wang et al, 2008). There are basically three types of REE fertilizers in China: Changle-Yizhisu (CY), which contains nitrate forms of REEs;…”

Bioaccumulation and effects of lanthanum on growth and mitotic index in soybean plants

“…In fact, China was the first country in the world to apply commercial REE-fertilizers to crops. It is estimated that REE fertilizers area applied to about 5% of the total agricultural land in China (Hu et al, 2004;Wang et al, 2008). In recent years, agricultural use of REE-fertilizers has extended to countries such as Korea, Japan, Australia, Switzerland, and the Philippines (Redling, 2006;Wang et al, 2008).…”