不同灌溉模式蔗田土壤呼吸动态  

Soil respiration dynamics in sugarcane cropland under different irrigation modes

作　　者：谭娟[1] 

机构地区：[1]上海市环境科学研究院,上海200233

出　　处：《生态学杂志》2017年第12期3493-3500,共8页Chinese Journal of Ecology

基　　金：水利部公益性行业科研专项经费项目(201301013);广西自治区农业科技成果转化资金项目(14125004-4)资助

摘　　要：为研究不同灌溉模式对甘蔗农田土壤呼吸的影响,以柳城05-136号为试验甘蔗品种,于2015年3—12月在广西崇左市江州区试验基地开展5种灌溉模式甘蔗土壤呼吸速率及主要环境因子的田间观测。结果表明:不同灌溉模式土壤呼吸速率的季节变化规律基本一致,以管灌土壤呼吸速率最高,季节平均值为4.50μmol·m^(-2)·s^(-1);微喷最低,为2.59μmol·m^(-2)·s^(-1);管灌分别比微喷、地埋滴灌、地表滴灌和喷灌高61.59%、27.61%、15.97%和12.33%,管灌与其他4种灌溉模式土壤呼吸速率差异达到极显著水平(P<0.01),说明管灌显著促进了土壤呼吸作用。就单因素模型而言,土壤呼吸速率与土壤温度呈现指数回归关系,其中地埋滴灌、地表滴灌、管灌和喷灌模式下该关系达极显著水平(P<0.01),而微喷模式下该关系达显著水平(P<0.5);土壤呼吸速率与土壤含水率之间仅在管灌模式下呈显著的二次项回归关系(P<0.05),其他模式下回归关系均不显著;与单因素模型相比,土壤呼吸速率与土壤温度和土壤含水率存在极显著(P<0.01)的指数-幂函数回归关系,拟合度R2在0.41~0.83之间,说明双因素复合模型能够更好地解释土壤呼吸变化。土壤呼吸温度敏感性系数在1.98~2.50之间,以管灌最为敏感,而喷灌最不敏感。研究结果为评估不同节水灌溉模式的生态环境效益及掌握甘蔗大田生态系统土壤呼吸特征提供科学依据。In order to investigate the effects of different irrigation modes on soil respiration in cropland of sugarcane cuhivar Liucheng 05-136, five types of irrigation, including subsurface drip irrigation （ SSDI）, surface drip irrigation （ SDI）, pipe irrigation （ PI）, sprinkler irrigation （SI）, and micro-sprinkler irrigation （MSI） , were employed. Field measurements of soil respira- tion rate and related environmental factors （soil temperature and soil water content） were conduc- ted at five growth phases （tillering; early, peak, and late elongation; and maturity） at the Sug- arcane Efficient Water-saving Irrigation Test Base in Chongzuo City of Guangxi from March to De- cember in 2015. Soil respiration rates in different treatments showed similar seasonal variability. Seasonal mean soil respiration rate was lowest in the MSI mode （2.59 μmol·m^（-2）·s^（-1） and highest in the PI mode （4.50μmol·m^（-2）·s^（-1）. Soil respiration in the PI mode was 61.59%, 27.61%, 15.97% and 12.33% higher than that in the MSI, SSDI, SDI and SI modes, respectively （P〈0.01）, which indicated that PI irrigation can enhance sugarcane soil respiration rate. The relationship between soil respiration and soil temperature was well explained by exponential functions. Correlations between respiration and temperature were highly significant （P〈0.01） under SSDI, SDI, PI and SI modes, and significant under the MSI mode （P〈0.05）. While the re- lationship between soil respiration and soil water content could be described with a quadratic function, the correlation was significant only under the PI mode （P〈0.05）. In comparison to sin- gle-factor equation, two-factor equations better predicted soil respiration rate, with coefficients being highly significant （ P 〈 0.01, R2 = 0.41 - 0.83 ）. The temperature sensitivity coefficient （ Q10 ） of soil respiration was 1.98-2.50. Pipe irrigation was the most temperature sensitive mode, while the least sensitive was the SI mode. These

关 键 词：节水灌溉 甘蔗 土壤呼吸 土壤温度 土壤水分 

分 类 号：S274[农业科学—农业水土工程] S566.1[农业科学—农业工程]