TY - JOUR
T1 - Status of paddy soils as affected by paddy rice and upland soybean rotation in northeast Japan, with special reference to nitrogen fertility
AU - Nishida, Mizuhiko
AU - Sekiya, Hiroyuki
AU - Yoshida, Koji
PY - 2013/4/1
Y1 - 2013/4/1
N2 - To investigate the current available nitrogen (N) and chemical properties of paddy soils affected by crop rotation between irrigated paddy rice (Oryza sativa L.) and upland soybean [Glycine max (L.) Merr.] (paddy-upland rotation), topsoils were collected from 22 fields of four different farmers in the northeastern region of Japan. Regardless of organic material application, a significant negative correlation was found between available soil N and an increase in the proportions of upland seasons to total crop seasons after the initiation of paddy-upland rotation. Soil total N and total carbon (C) also tended to decrease with an increase in upland frequency. In fields with repeated applications of cattle manure compost, the soil available N was higher than in fields where only crop residue was applied. A significant negative correlation was also found between the soil available N:total N ratio and upland frequency. This indicates that the part of soil N related to available N was notably lost by the use of paddy fields as upland fields. In order to sustain available soil N over the minimum suitable level of 80 mg kg-1, upland frequency should not exceed 65% when only crop residues and no other organic materials are applied. The upland frequency can be raised by the repeated application of organic materials which maintain a higher level of available soil N. The results imply that care should be taken to maintain the N fertility of paddy soil at a suitable level in paddy-upland rotation, and that upland frequency and organic materials applied are important factors to do this.
AB - To investigate the current available nitrogen (N) and chemical properties of paddy soils affected by crop rotation between irrigated paddy rice (Oryza sativa L.) and upland soybean [Glycine max (L.) Merr.] (paddy-upland rotation), topsoils were collected from 22 fields of four different farmers in the northeastern region of Japan. Regardless of organic material application, a significant negative correlation was found between available soil N and an increase in the proportions of upland seasons to total crop seasons after the initiation of paddy-upland rotation. Soil total N and total carbon (C) also tended to decrease with an increase in upland frequency. In fields with repeated applications of cattle manure compost, the soil available N was higher than in fields where only crop residue was applied. A significant negative correlation was also found between the soil available N:total N ratio and upland frequency. This indicates that the part of soil N related to available N was notably lost by the use of paddy fields as upland fields. In order to sustain available soil N over the minimum suitable level of 80 mg kg-1, upland frequency should not exceed 65% when only crop residues and no other organic materials are applied. The upland frequency can be raised by the repeated application of organic materials which maintain a higher level of available soil N. The results imply that care should be taken to maintain the N fertility of paddy soil at a suitable level in paddy-upland rotation, and that upland frequency and organic materials applied are important factors to do this.
KW - available nitrogen
KW - paddy soil
KW - paddy-upland rotation
KW - rice
KW - soybean
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U2 - 10.1080/00380768.2012.762588
DO - 10.1080/00380768.2012.762588
M3 - Article
AN - SCOPUS:84878458921
VL - 59
SP - 208
EP - 217
JO - Soil Science and Plant Nutrition
JF - Soil Science and Plant Nutrition
SN - 0038-0768
IS - 2
ER -