| 模拟增温对冬小麦-大豆轮作农田土壤呼吸的影响 |
| 摘要点击 2117 全文点击 1372 投稿时间：2012-02-10 修订日期：2012-03-27 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 模拟增温 土壤呼吸 土壤温度 土壤湿度 农田 |
| 英文关键词 simulated warming soil respiration soil temperature soil moisture cropland |
|
| 中文摘要 |
| 为研究模拟增温对冬小麦-大豆轮作农田土壤呼吸的影响,设置了随机试验,观测增温和对照处理的农田土壤呼吸速率. 采用LI-8100开路式土壤碳通量测量系统对农田土壤呼吸速率进行观测,并采用气压过程分离技术(BaPS)测定土壤CO2产生速率. 在观测土壤呼吸速率的同时,观测了两处理的土壤温度、湿度. 结果表明,不同增温处理下土壤呼吸速率的季节变异趋势基本一致,其季节变异与土壤温度的变异具有一致性. 冬小麦田增温和对照处理的平均土壤呼吸速率分别为(3.54±0.60) μmol·(m2·s)-1和(2.49±0.53) μmol·(m2·s)-1,大豆田增温和对照处理平均土壤呼吸速率分别为(4.80±0.46) μmol·(m2·s)-1和(4.14±0.29) μmol·(m2·s)-1. 模拟增温显著促进了冬小麦田和大豆田的土壤呼吸作用,在冬小麦生长后期(抽穗-成熟期)增温和对照处理的土壤呼吸速率差异最为明显(P<0.05); 在大豆开花-结荚期以及鼓粒-成熟期增温与对照的土壤呼吸速率分别存在极显著性(P<0.01)和显著性(P<0.05)差异. 进一步的研究表明,模拟增温和对照处理土壤呼吸均与土壤温度存在极显著(P<0.01)的指数回归关系,但增温处理的土壤呼吸的温度敏感性明显高于对照,小麦生长季增温和对照处理的土壤呼吸温度系数Q10值分别为1.83和1.26,大豆生长季两处理的土壤呼吸温度系数Q10值分别为2.85和1.70. 本研究表明,增温显著促进了农田土壤呼吸作用. |
| 英文摘要 |
| This study was aimed to investigate the effects of simulated warming on soil respiration in a cropland under winter wheat-soybean rotation. Randomized experiments were carried out in the cropland. 6 Plots were arranged and there were 2 treatments, simulated warming and control. A portable soil CO2 fluxes system (LI-8100) was used to measure soil respiration rates. Soil CO2 production rates were determined by using a Barometric Process Separation (BaPS) method. Soil temperature and soil moisture were simultaneously determined when measuring soil respiration rates. Results indicated that soil respiration rates in different treatments showed similar seasonal variability, in accordance with the variability in soil temperature. Seasonal mean soil respiration rates for simulated warming and control treatments were 3.54 and 2.49 μmol·(m2·s)-1, respectively, during the winter wheat growth season, while they were 4.80 and 4.14 μmol·(m2·s)-1, respectively, during the soybean growth season. Simulated warming significantly (P<0.05) enhanced soil respiration during both the winter wheat and soybean growth seasons. The impact of simulated warming on soil respiration was particularly obvious during the later growth stages of winter wheat (from heading to maturity stages) and soybean (from flowing to maturity stages). Further investigations suggested that, for both the winter wheat and soybean growth seasons, the relationship between soil respiration and soil temperature could be well explained (P<0.01) by exponential functions. The temperature sensitivity (Q10) of soil respiration in the simulated warming treatments was significantly higher than that in the control treatments. The Q10 values for the simulated warming and control treatments were 1.83 and 1.26, respectively, during the winter wheat growth season, while they were 2.85 and 1.70, respectively, during the soybean growth season. This study showed that simulated warming significantly increased soil respiration in the cropland. |
|
|
|
