Jensen Erik Steen
Section of Plant Nutrition, Environ. Sci. and Technol. Dep. Risø National Lab., DK-4000, Roskilde, Denmark.
J Environ Qual. 1994 Sep;23(5):1045-1050. doi: 10.2134/jeq1994.00472425002300050028x.
Field pea (Pisum sativum L.) crop residues labeled with N were incorporated during September in small monolith lysimeters of a sandy loam soil. The leaching of N-labeled and nonlabeled NO to below 45 cm was studied during the subsequent 2 to 3 yr comparing (i) planted vs. unplanted soil and (ii) with and without pea residue incorporation. The peak flux of labeled NO -N from uncropped soil occurred in December. During the first leaching period (September-April), 15 and 7% of the residue N was recovered as NO in the percolate in the two experiments, corresponding to 18 and 13% of total NO -N in the percolates, respectively. The difference observed in leaching of labeled N in the two experiments was mainly due to a much higher drainage volume in the first experiment. The different residue particle sizes, 10 mm or <3 mm, used in the two experiments may have influenced the immobilization-mineralization of N in the soil differently and consequently the potential for NO leaching. Pea residue N constituted 10 to 15% and 5% of total NO -N leached from unplanted soil in the second and third leaching periods, respectively. Incorporating the ground pea residues reduced the total amount of NO leached by 15% during the first leaching period, indicating that the pea residue may be an important factor in controlling leaching losses. Ryegrass (Lolium perenne L.) established on lysimeters at the time of residue incorporation reduced the total leaching of N in the first leaching period by 15%, but in the second and third leaching period grass eliminated NO leaching completely.
9月期间，将用氮标记的豌豆（Pisum sativum L.）作物残茬施入砂壤土的小型整块土壤渗漏计中。在随后的2至3年中，研究了标记氮和未标记氮的硝酸盐淋溶至45厘米以下的情况，比较了（i）种植土壤与未种植土壤，以及（ii）有豌豆残茬施入和无豌豆残茬施入的情况。未种植土壤中标记硝酸盐氮的峰值通量出现在12月。在第一个淋溶期（9月至4月），在两个实验中，分别有15%和7%的残茬氮以硝酸盐形式在渗滤液中回收，分别相当于渗滤液中总硝酸盐氮的18%和13%。两个实验中标记氮淋溶的差异主要是由于第一个实验中的排水量高得多。两个实验中使用的不同残茬粒径（10毫米或小于3毫米）可能对土壤中氮的固定-矿化有不同影响，从而影响硝酸盐淋溶的可能性。在第二个和第三个淋溶期，豌豆残茬氮分别占未种植土壤中淋溶总硝酸盐氮的10%至15%和5%。在第一个淋溶期，施入磨碎的豌豆残茬使淋溶的硝酸盐总量减少了15%，这表明豌豆残茬可能是控制淋溶损失的一个重要因素。在残茬施入时在渗漏计上种植的黑麦草（Lolium perenne L.）在第一个淋溶期使氮的总淋溶量减少了15%，但在第二个和第三个淋溶期，黑麦草完全消除了硝酸盐淋溶。
