摘要
研究双季稻不同稻草还田模式下土壤总有机碳、活性有机碳及碳库管理指数的变化,对稻田合理利用稻草资源和稻田土壤固碳具有重要意义.本文通过3 年田间定位试验,研究了双季稻无草＋翻耕＋冬季免耕休闲（CK）、双季稻草焚烧还田＋翻耕＋冬季免耕休闲（BST）、双季稻稻草覆盖免耕＋冬季高桩免耕（SNTH）、双季稻稻草覆盖免耕＋冬季深埋（SNTB）和双季稻稻草还田＋翻耕＋冬季稻草翻埋（STB）5 种周年稻草还田模式对不同层次土壤有机碳、活性碳以及碳库管理指数的影响,旨在探明双季稻田稻草高效碳管理模式,结果表明：无论是翻耕还是免耕,稻草还田均能显著提高耕层0-15 cm 土壤有机碳和活性有机碳含量;稻草覆盖免耕显著增加0-5 cm 土壤有机碳、活性有机碳以及土壤碳库管理指数,而双季稻稻草覆盖免耕结合冬季翻埋稻草则有利于土壤有机碳在5-15 cm 积累,弥补因稻草覆盖免耕有机碳在整个耕层累积的不足.因此,认为稻田免耕覆盖稻草＋冬季翻埋稻草是适合双季稻田的周年稻草还田增碳的技术模式.
A 3-year field located experiment was conducted to study the effects of different rice straw returning ways on soil organic carbon, active organic carbon and soil carbon pool management index (CPMI) in different layer and to investigate a efficient carbon management mode under a double rice-cropping system. Five treatments included no straw and tillage (CK), incinerated burned straw returning and tillage (BST), coverd rice straw returning and no tillage and high stake (SNTH), coverd rice straw returning and no tillage and bury straw (SNTB), rice straw returning and tillage and bury straw (STB). The result indicated that total organic carbon (TOC) and active organic carbon (AOC) pool were decreased with deeper layer. Whether tillage or not, 0~15 cm soil organic carbon and active organic carbon contents was significantly improved by straw incorporation. The 0~5 cm soil organic carbon, active organic carbon and soil carbon pool management index was increased significantly by coverd rice straw returning with no tillage measure. Based on this mode of rice straw returning, then burying straw in winter was beneficial to soil organic carbon and can increase carbon manegement index in 5~15 cm soil layer. This is an effectively way to compensate for the shortage of organic carbon accumulation in surface under the straw mulching and no tillage treatment. It is considered a suitable straw returning technology model for double-cropping systems.
出处
《生态环境学报》
CSCD
北大核心
2016年第4期563-568,共6页
Ecology and Environmental Sciences
基金
国家科技支撑计划项目(2013BAD11B02)
国家自然科学基金项目(31300413)
关键词
双季稻
稻草还田
有机碳
碳库管理指数
double-crop rice system
rice straw returning to paddy soil
organic carbon
carbon pool management index
