Soil health and sustainability of rice-wheat cropping system (RWCS) in the Indo-Gangetic plains (IGP) in South Asia are possibly adversely influenced due to in-situ burning of large quantities of rice residues. Instead of burning, it is increasingly being advocated to incorporate the crop residues into the soil. In a field experiment, effects of four nitrogen (N) levels (0, 90, 120 and 150 kg N ha^− 1) as main-plots and four levels of rice straw (RS) incorporation (to a depth of 0.10–0.15 m) (0, 5, 7.5 and 10 t ha^− 1) as sub-plots in split plot design were studied on soil enzymatic activities at two stages i.e. maximum tillering (MT) and flowering (FL) of wheat, and crop yield after 7 years. Activities of dehydrogenase, fluorescein diacetate, alkaline phosphatase, acid phosphatase, phytase, urease, l-asparaginase, cellulase, xylanase, β-glucosidase, peroxidase and phenol oxidase enzymes and grain yield of wheat in the treatment receiving 120 kg N ha^− 1 and 10 t ha^− 1 RS incorporation were significantly higher than in the control (without N and RS incorporation). The enzyme activities except peroxidase and phenol oxidase were dominated in rhizosphere than in the bulk soil, and at MT rather than at FL stage. Principal component analysis revealed that l-asparaginase, and phenol oxidase activities can be used as the most sensitive and reliable indicators for assessing soil quality under RWCS when rice residues are incorporated into the soil.

中文翻译：

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氮和秸秆还田对小麦根际生物土壤质量指标的时空变化

南亚印度恒河平原（IGP）的土壤健康和水稻-小麦种植系统（RWCS）的可持续性可能由于原地燃烧大量稻米残留物而受到不利影响。除了燃烧以外，越来越多的人主张将农作物残留物掺入土壤中。在田间试验中，四种氮（N）水平（0、90、120和150 kg N ha ^-1）作为主样，并掺入四种稻草（RS）（深度为0.10–0.15 m） ）（0、5、7.5和10 t ha ^{− 1}）作为分割样地设计的子图，研究了小麦最大分till（MT）和开花（FL）两个阶段的土壤酶活性，以及​​7年后的作物产量。脱氢酶，荧光素二乙酸酯，碱性磷酸酶，酸性磷酸酶，肌醇六磷酸酶，脲酶，活动升-asparaginase，纤维素酶，木聚糖酶，β葡糖苷酶，过氧化物酶和酚氧化酶和接收在处理小麦籽粒产量120千克Ñ公顷^{- 1}和10 t ha ^-1 RS掺入量显着高于对照（无N和RS掺入）。除过氧化物酶和苯酚氧化酶外，根际土壤中的酶活性占主导地位，而不是在块状土壤中，在MT阶段而不是FL阶段。主成分分析表明，升当将稻米残留物掺入土壤时，天冬酰胺酶和酚氧化酶的活性可用作评估RWCS下土壤质量的最灵敏和可靠的指标。