ABSTRACT

A long-term experiment on conservation agriculture was designed to study different nitrogen dynamics in maize based cropping system at Research Farm, Bihar Agricultural University, Sabour dominated by Inceptisols in eastern Indo-Gangetic plains. The maize based cropping system was studied having various tillage (T1: Zero Tillage; T2: Permanent Raised Bed; T3: Conventional Tillage) and cropping sequences (C1: Maize+Soybean-Wheat; C2: Maize-Wheat; C3: Maize-Maize; C4: Maize-Mustard; C5: Maize-Chick pea; C6: Soybean-Maize) with a special reference to changes in different N fractions. Significant correlation was found between different N fractions (Total N, Ammoniacal-N, Nitrate-N, Total Hydrolysable-N, Hydrolysable ammoniacal-N, Amino Acid-N, Amino Sugar-N, Unidentified-N, Non-hydrolysable N, Available N) and yield as well as N uptake of maize. Zero tillage system under maize-chickpea cropping was found superior in terms of amount of all fractions of N and was also responsible for the improved yield, N uptake, physico-chemical properties and fertility levels of the soils. The organic forms of N, especially total hydrolysable and amino acid N, showed strong positive correlations with available N. Overall, organic N constituted a dominate part of soil N and played key role in soil N cycling and crop production. Not only organic N mineralized into mineral N for plant uptake, it also provided some organic components for plant direct absorption.

摘要

在印度-恒河平原东部以 Inceptisol 为主的萨布尔比哈尔农业大学研究农场，设计了一项关于保护性农业的长期试验，以研究基于玉米的种植系统中不同的氮动态。研究了基于玉米的种植系统，具有不同的耕作方式（T1：零耕；T2：永久高架床；T3：常规耕作）和种植顺序（C1：玉米 + 大豆 - 小麦；C2：玉米 - 小麦；C3：玉米 - 玉米；C4：玉米-芥末；C5：玉米-鹰嘴豆；C6：大豆-玉米），特别提到了不同 N 组分的变化。在不同的氮组分（总氮、氨氮、硝酸盐氮、总水解氮、水解氨氮、氨基酸氮、氨基糖氮、未鉴定氮、非水解氮、可用氮）之间发现显着相关性N) 和产量以及玉米的 N 吸收。玉米鹰嘴豆种植下的零耕系统在所有 N 部分的数量方面均表现优异，并且还有助于提高土壤的产量、N 吸收、物理化学性质和肥力水平。氮的有机形态，尤其是总水解氮和氨基酸氮，与有效氮呈强正相关。总体而言，有机氮构成了土壤氮的主要部分，在土壤氮循环和作物生产中发挥了关键作用。不仅有机氮矿化成矿物质氮供植物吸收，还提供一些有机成分供植物直接吸收。特别是总水解氮和氨基酸氮，与有效氮呈强正相关。总体而言，有机氮构成土壤氮的主要部分，在土壤氮循环和作物生产中发挥关键作用。不仅有机氮矿化成矿物质氮供植物吸收，还提供一些有机成分供植物直接吸收。特别是总水解氮和氨基酸氮，与有效氮呈强正相关。总体而言，有机氮构成土壤氮的主要部分，在土壤氮循环和作物生产中发挥关键作用。不仅有机氮矿化成矿物质氮供植物吸收，还为植物直接吸收提供了一些有机成分。