Natural 15N and 13C abundance in Andisols influenced by long-term fertilization management in Japan

• Published in: Soil science and plant nutrition (Tokyo) Vol. 48; no. 4; pp. 555 - 562
• Main Authors: "Zhao, B. (National Agricultural Research Center, Tsukuba, Ibaraki (Japan)), Maeda, M, Ozaki, Y.
• Format: Journal Article
• Language: English
• Published: Tokyo Taylor & Francis Group 01.08.2002; Japanese Society of Soil Science and Plant Nutrition
• Subjects: Andisols; ANDOSOLS; Biological and medical sciences; CARBON; fertilization management; FERTILIZER APPLICATION; Fundamental and applied biological sciences. Psychology; ISOTOPES; JAPAN; natural abundance; NITROGEN; UPLAND CROPS; UPLAND SOILS
• ISSN: 0038-0768; 1747-0765
• DOI: 10.1080/00380768.2002.10409238

"Two field experiments were conducted on Andisols in Japan to evaluate the changes in the natural sup15 N and sup13 C abundance in the soil profile and to determine whether the values of d sup15 N could be used as an indicator of fertilizer sources or fertilizer fate. The 6-year experiment conducted at the National Agricultural Research Center (NARC) consisted of the following treatments: application of swine colnpost (COMPOST), slow-release nitrogen fertilizer (SRNF), readily available nitrogen fertilizer (RANF), and absence of fertilization (CONTROL). Experimental plots located at the Nippon Agricultural Research Institute (NARI) received cattle compost at different rates for 12 years; a forest soil at this site was sampled for comparison. Swine compost application led to a considerable change in the d sup15 N distribution pattern in the soil profile, with the highest d sup15 N values recorded in the top 20cm layers of the COMPOST plot, decreasing in the sequence of CONTROL >-RANF>SRNF, mainly due to the relatively high d sup15 N value of swine compost and its subsequent decomposition. In contrast, SRNF application resulted in the lowest d**15N values in soil, indicating the presence of negligible nitrogen losses relative to input and low nitrogen cycling rates. Values of d**15N increased with compost application rates at NARI. In the leachate collected at 1-m depth, the d sup15 N values decreased in the sequence of COMPOST>RANF>-CONTROL>SRNF. The d sup13 C values in soil peaked in the 40-60cm layers for all the fertilizers. The d sup13 C value was lowest in forest soil due to the presence of plant residues in soil organic matter. These results indicated that the d sup15 N values in the upper soil layers or leachate may enable to detect pollution sources of organic or inorganic nitrogen qualitatively in Andisols."