西南旱地不同种植模式下土壤呼吸及水热因子对极端低温的响应

发布时间：2018-04-04 07:34

本文选题：极端气候　切入点：碳排放　出处：《草业学报》2017年06期

【摘要】：极端气候频现是全球气候变化的重要特征之一,其中极端低温不仅影响农业生产,也影响着农业碳排放。土壤呼吸作为农业碳排放的主要途径,缺乏在极端低温环境下的深入研究。本研究以我国西南地区旱地为研究对象,通过测定冬季低温环境下的土壤呼吸及其水热因子,分析了土壤呼吸等在极端低温环境下的响应特征,发现秸秆覆盖条件下紫云英与油菜混作的土壤呼吸和根呼吸最大,种植紫云英可显著提高10cm处的土壤温度、土壤含水量和土壤电导率;在极端低温环境下,土壤呼吸和根呼吸显著降低,土壤呼吸的温度敏感性显著提高,Q10值由0.31增加到1.19,同时改变了土壤呼吸与土壤电导率之间的关系。无秸秆覆盖时紫云英单作、紫云英与油菜混作的根呼吸比重分别提高了12.07%和8.15%;而秸秆覆盖下紫云英单作、油菜单作以及紫云英与油菜混作的根呼吸比重分别降低了28.55%、38.87%和24.80%。
[Abstract]:Extreme climate frequency is one of the important characteristics of global climate change, in which extreme low temperature not only affects agricultural production, but also affects agricultural carbon emissions.Soil respiration, as the main way of carbon emission from agriculture, is lack of deep research in extreme low temperature environment.In this study, the response characteristics of soil respiration and its hydrothermal factors in extremely low temperature environment were analyzed by measuring the soil respiration and its hydrothermal factors in the dry land of southwest China.The results showed that the soil respiration and root respiration were the largest under straw mulching, and the soil temperature, soil water content and soil conductivity were significantly increased by planting Ziyun in 10cm, and in the extremely low temperature environment, the soil water content and the electrical conductivity of the soil were significantly increased under the condition of straw mulching.Soil respiration and root respiration decreased significantly, the temperature sensitivity of soil respiration increased significantly from 0.31 to 1.19, and the relationship between soil respiration and soil electrical conductivity was changed.Without straw mulching, the root respiration ratio of Zyunyunxiao mixed with rapeseed increased by 12.07% and 8.15%, respectively, while the root respiration ratio of single cropping, rapeseed monoculture and mixed cropping with rapeseed decreased 28.5555% and 24.80% respectively under straw mulching.
【作者单位】：西南大学农学与生物科技学院南方山地农业教育部工程研究中心三峡库区生态环境教育部重点实验室;
【基金】：公益性行业(农业)科研专项(201503127) 国家自然科学基金项目(31271673)资助
【分类号】：S154.1

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