This chapter provides information on some recent developments of fertilizer production and use that improve nutrient efficiency and minimize environmental impact. The nutrients discussed are mainly N, P, and S. Improving N nutrient efficiency includes use of (1) controlled-release coated urea products, (2) slowrelease urea–aldehyde polymer products, (3) urea supergranules for deep placement, (4...

Synthetic (e.g. urea) and organic fertilizers (e.g. compost) differed markedly in N isotope composition and the greater the difference between organic and synthetic fertilizer the more robust will be the differentiation of crops and vegetable grown under different farming systems. The objective of this study was to compare nitrogen and carbon isotope composition of organic fertilizers and manur...

Microbial biomass nitrogen and carbon were studied in long-term field experiments with continuous cultivation of silage maize and with crop rotation. a positive effect of organic fertilizers on the microbial biomass nitrogen and the carbon content in soil was observed. Statistically significant effect of organic fertilizers on the higher content of microbial biomass C and n was established in t...

Urine contains about 50 % of the phosphorus (P) and about 90 % of the nitrogen (N) excreted by humans and is therefore an interesting substrate for nutrient recovery. Source-separated urine can be used to precipitate struvite or, through a newly developed technology, nitrified urine fertilizer (NUF). In this study, we prepared (33)P radioisotope- and stable (15)N isotope-labeled synthetic NUF (...

This Bulletin discusses several manufacturing processes for organic compound fertilizers overseas and in Taiwan. The different formulations of N-P2O5-K2O in the fertilizers are also reported. The yield response of different crops from the application of organic compound fertilizer reflects their superiority over organic fertilizers. Experiments also showed that the use of organic compound ferti...

Nitrification inhibitors (NIs) delay the oxidation of ammonium by soil microorganisms, maintaining a higher proportion of applied nitrogen (N) in the soil by preventing nitrate-N loss from leaching and gaseous N losses from nitrification and denitrification. Thus, a large number of studies have shown N fertilizers with NIs are more environmentally friendly. In contrast, there are only a lim...

Our attitude towards mineral nitrogen (N) fertilizers is ambivalent. N fertilizers have on one hand increased our supply of food, feed and other bio-based raw materials tremendously and also improved the use efficiency of land and labor, but have on the other hand a negative impact on the quality of the environment and contributed to the depletion of fossil fuel reserves. This awareness has res...

Abstract. Large quantities of N fertilizers may be lost in rice fields by nitrification-denitrification. In this connection, experiments were carried out in order to compare the effects from slow-release N-fertilizers (ISODUR) and products integrated with diciandiamide (DCD), a nitrification inhibitor, with the N splitting method applied in two or three times on the rice growth and yield. The e...

Nitrogen is the most important essential nutrient that plays a major role in achieving maximum crop yield in agriculture. Therefore, nitrogen fertilizers such as ammonium sulfate and urea have been extensively used in modern agriculture. These fertilizers are generally oxidized to nitrate via nitrite by nitrifying microorganisms in the agricultural field (4, 10, 11). The serious environmental p...

A field experiment was conducted to assess the effect of farmyard (cattle) manure (FYM) and inorganic nitrogen (N) phosphorus (P) fertilizers on growth and tuber yield of potato (Solanum tuberosum L.). The treatments consisted of factorial combination of 4 levels of FYM (0. 10, 20 and 30 t h-1) and three levels of inorganic NP fertilizers (0, 33.3%, 66.6% recommended rates) laid out in a Random...