@article{oai:repository.naro.go.jp:00001185,
 author = {住田, 弘一 and SUMIDA, Hirokazu and 加藤, 直人 and KATO, Naoto and 西田, 瑞彦 and NISHIDA, Mizuhiko},
 journal = {東北農業研究センター研究報告, Bulletin of TOHOKU Agricultural Research Center},
 month = {Mar},
 note = {Recently, the fate of nitrogen in some organic matter has been studied using organic matter labeled with <15>^N, however <15>>^N labeling requires many expenditures and labor. In a long-term experiment, the comparison of nitrogen balance sheets between compost applied and non-applied plots is useful to estimate the fate of the applied nitrogen. In this report, the fate of applied fertilizer nitrogen and applied compost nitrogen during the last nineteen years (1981～1999) was estimated by long-term experiments with rice straw compost (1968～) and livestock waste compost (1973～) on gray lowland soil in a cool region (NARCT, Omagari, Akita). The nitrogen balance in the plot without nitrogen application indicated that about 3-4kg/10a of nitrogen every year was supplied through irrigation water, rainfall and biological fixation. Fertilizer nitrogen applied at 8kgN/10a as basal and supplement applications scarcely remained in the plow layer (topsoil), and about 4kgN of that was taken up by rice plants, and about 4kgN was lost. Nearly 2kgN of rice straw compost nitrogen applied at 11kgN/10a was accumulated in the topsoil. Nearly 3kgN of that was recovered by rice plants and the remainder (about 6.5kgN) was lost. When the application rate of rice straw compost was larger than 2t/10a, rice grain yield leveled off (20% higher than without rice straw compost), and the nitrogen recovery by rice plants decreased and the nitrogen loss increased. About 5kgN of the livestock waste compost nitrogen applied at 17kgN/10a accumulated in the topsoi1, about 6kgN of that was recovered by rice plants and the remainder (about6kgN) was lost, 有機物中の窒素の行方にっいては, 近年, 重窒素標識法による解析が始められているが, 長期連用下におけるその行方にっいては差し引き法による推定が有効である。そこで, 寒冷地灰色低地土水田 (東北農業研究センター大曲研究拠点内) における, 稲わら堆肥 (1968年～) 及び家畜ふん堆肥 (1973年～) の長期連用試験において, 堆肥の肥効が安定した1981年以降の19年間について, 化成肥料及び堆肥中の窒素の行方を差し引き法により推定した。窒素無施用栽培における窒素収支からみると, 毎年, 系外から約3～4kg／10aの窒素富化が認められた。10a当たり8kgの化成肥料窒素の作土への集積は見かけ上認められず, 水稲による収奪が約4kg, 系外への損失が約4kgであった。10a当たり11kg (堆肥現物2トン) の稲わら堆肥中の窒素は, 見かけ上土壌への集積が2㎏弱, 水稲による収奪が3kg弱, 系外への損失が約6．5㎏であった。稲わら堆肥の施用量が2t／10a以上で水稲収量は一定 (2割増収) になり, 水稲による収奪割合が減少し, 系外への損失割合が増大した。10a当たり17kg (堆肥現物3.6トン) の家畜ふん堆肥中の窒素は, 見かけ上土壌への集積が約5kg, 水稲による収奪が約6kg, 系外への損失が約6kgであった。},
 pages = {49--59},
 title = {寒冷地灰色低地土水田における堆肥長期連用試験からみた化成肥料及び堆肥中の窒素の行方},
 volume = {100},
 year = {2002},
 yomi = {スミダ, ヒロカズ and カトウ, ナオト and ニシダ, ミズヒコ}
}