不同施氮水平下杨树-苋菜间作系统对土壤氮素流失的影响

应用生态学报

不同施氮水平下杨树-苋菜间作系统对土壤氮素流失的影响

褚军¹,薛建辉^1**,吴殿鸣²,金梅娟¹,吴永波¹

(¹南京林业大学生物与环境学院江苏省林业生态工程重点实验室, 南京 210037; ²苏州科技学院, 江苏苏州 215009)

出版日期:2014-09-18 发布日期:2014-09-18

Effects of poplar-amaranth intercropping system on the soil nitrogen loss under different nitrogen applying levels.

CHU Jun¹, XUE Jian-hui¹, WU Dian-ming², JIN Mei-juan¹, WU Yong-bo^1

(¹Jiangsu Province Key Laboratory of Forest Ecological Engineering, College of Biology and Environment, Nanjing Forestry University, Nanjing 210037, China; ^2Suzhou University of Science and Technology, Suzhou 215009, Jiangsu, China)

Online:2014-09-18 Published:2014-09-18

摘要/Abstract

摘要：

采用田间试验方法,研究了杨树苋菜间作系统,即株行距2 m×5 m(L₁)和2 m×15 m(L₂)在0(N₀)、91(N₁)、137(N₂)和183(N₃) kg·hm^-2施氮水平下的土壤氮素流失特征.结果表明: 不同施氮水平对地表径流量、淋溶量和土壤侵蚀量的控制效果均为L₁＞L₂＞L₃ (单作苋菜);L₁、L₂地表径流量分别比L₃降低65.1%、55.9%;L₁、L₂距林带0.5 m处淋溶量比L₃降低30.0%、28.9%,距林带1.5 m处淋溶量比L₃降低25.6%、21.9%;L₁、L₂土壤侵蚀量分别比L₃降低65.0%、55.1%.对地表径流和淋溶损失中TN、NO₃^--N、NH₄⁺-N流失量的控制效果均为L₁＞L₂＞L₃;常规施氮(91 kg·hm^-2)水平下,L₁地表径流中TN、NO₃^--N、NH₄⁺-N流失量较L₃分别降低62.9%、45.1%、69.2%,L₂较L₃分别降低23.4%、6.9%、46.2%;杨树间作密度越大、距离林带越近,对土壤NO₃^--N、NH₄⁺-N的淋溶损失削减作用越强.同一间作密度下,随着施氮量的增加,地表径流中NO₃^--N流失比例减少,NH₄⁺-N流失比例增加;淋溶流失中
NO₃^--N、NH₄⁺-N浓度变化趋势一致,均为 N₃＞N₂＞N₁＞N₀.

Abstract: Characteristics of soil nitrogen loss were investigated based on field experiments in two types of poplaramaranth intercropping systems (spacing: L₁ 2 m×5 m, L₂ 2 m×15 m) with four N application rates, i.e., 0 (N₁), 91 (N₂), 137 (N₃) and 183 (N₄) kg·hm^-2. The regulation effects on the soil surface runoff, leaching loss and soil erosion were different among the different types of intercropping systems: L₁＞L₂＞L₃(amaranth monocropping). Compared with the amaranth monocropping, the soil surface runoff rates of L₁ and L₂ decreased by 65.1% and 55.9%, the soil leaching rates of L₁ and L₂ with a distance of 0.5 m from the poplar tree row decreased by 30.0% and 28.9%, the rates with a distance of 1.5 m decreased by 25.6% and 21.9%, and the soil erosion rates decreased by 65.0% and 55.1%, respectively. The control effects of two intercropping systems on TN, NO₃^--N and NH₄⁺-N in soil runoff and leaching loss were in the order of L₁＞L₂＞L₃. Compared with the amaranth monocropping, TN, NO₃^--N and NH₄⁺-N loss rates in soil runoff of L₁ decreased by 62.9%, 45.1% and 69.2%, while the loss rates of L₂ decreased by 23.4%, 6.9% and 46.2% under N₁ (91 kg·hm^-2), respectively. Higher treeplanting density and closer positions to the polar tree row were more effective on controlling the loss rates of NO₃^--N and NH₄⁺-N caused by soil leaching. The loss proportion of NO₃^--N in soil runoff decreased with the increasing nitrogen rate under the same treeplanting density, while that of NH₄⁺-N increased. Leaching loss of NO₃^--N had a similar trend with that of NH₄⁺-N, i.e., N₃＞N₂＞N₁＞N₀.

褚军1,薛建辉1**,吴殿鸣2,金梅娟1,吴永波1. 不同施氮水平下杨树-苋菜间作系统对土壤氮素流失的影响[J]. 应用生态学报.

CHU Jun1, XUE Jian-hui1, WU Dian-ming2, JIN Mei-juan1, WU Yong-bo1. Effects of poplar-amaranth intercropping system on the soil nitrogen loss under different nitrogen applying levels.[J]. Chinese Journal of Applied Ecology.