夏闲期耕作下旱地土壤有机碳库与温度和含水量季节变化及关系研究  

Study on Seasonal Variation and Relationship between Soil Organic Carbon Pool and Water,Temperature in Dry Land under Summer Idle Tillage

作　　者：薛建福[1] 濮超 祁泽伟 高志强[1] XUE Jianfu;PU Chao;QI Zewei;GAO Zhiqiang(College of Agronomy,Shanxi Agricultural University,Taigu,Shanxi 030801;College of Agriculture and Ecological Engineering,Hexi University,Zhangye,Gansu 734000)

机构地区：[1]山西农业大学农学院,山西太谷030801 [2]河西学院农业与生态工程学院,甘肃张掖734000

出　　处：《核农学报》2024年第1期190-199,共10页Journal of Nuclear Agricultural Sciences

基　　金：国家自然科学基金(32272235)。

摘　　要：为明确夏闲期耕作下土壤有机碳(SOC)库与温度和含水量的季节变化及其相互关系,设置夏闲期免耕、翻耕和深松3种耕作处理,分析了黄土高原旱地麦田SOC和易氧化有机碳(POxC)含量的季节变化、土壤含水量和温度的季节变化、以及碳库与温度和含水量变化的关系。结果表明,在冬小麦生育期内,随着生育进程的推进,翻耕和深松处理0~5和5~10 cm土层SOC含量呈先升高后降低的变化趋势,而POxC含量呈“降低—升高—再降低”的变化趋势;土壤质量含水量变化均呈“增加—降低—再增加”的变化趋势,而土壤温度呈先降低后升高的变化趋势。回归分析发现,5~10 cm土层土壤质量含水量与SOC含量呈线性关系(P<0.05),与POxC含量呈二次多项式关系(P<0.05),尤其与免耕和深松处理相比,翻耕处理拟合效果更佳。此外,0~5和5~10 cm土层土壤温度变化与SOC含量无显著相关性,而日最高温度、日平均温度和日最低温度与POxC含量呈显著负相关。综上所述,不同夏闲期耕作下旱地麦田0~10 cm土层POxC含量季节变化与土壤质量含水量和温度变化密切相关,而SOC含量变化对土壤温度变化的敏感性较弱。本研究结果为旱地麦田碳库管理提供了理论依据。This study aimed to understand the variations in soil organic carbon(SOC)pools,soil temperature and water content and their relationships to mitigate climate change.Therefore,a field experiment was conducted to investigate the seasonal dynamics of SOC,permanganate oxidizable organic carbon(POxC)concentrations,as well as their relationships with soil temperature and water content under different tillage practices during the summer fallow in the drylands of the Loess Plateau in China.The experiment included three tillage practices,i.e.,no tillage,plough tillage and subsoiling tillage during the summer fallow.Results showed that the seasonal changes in the SOC concentrations increased and then decreased at both 0-5 and 5-10 cm depths under plough tillage and subsoiling tillage treatments during the growth period of winter wheat.While the seasonal changes in POxC concentration,soil water content and soil temperature fluctuated.Regression analysis revealed that the soil water content at the 5-10 cm depth had a linear relationship with the SOC concentrations and a quadratic polynomial relationship with the POxC concentrations(P<0.05),with a better fit under the plough tillage treatment compared to the no tillage and subsoiling tillage treatments.The SOC concentrations showed no significant response to variations in soil temperature at both the 0-5 and 5-10 cm depths.In contrast,the POxC concentrations demonstrated a negative correlation with daily maximum temperature,daily mean temperature and daily minimum temperature.In summary,the findings of our study demonstrated that the seasonal changes in the POxC concentration at 0-10 cm depth were closely related to variations in soil temperature and water content,while seasonal changes in the SOC concentrations were less sensitive to soil temperature under summer fallow tillage treatments in the drylands.This study provides a theoretical basis for the scientific management of SOC pools in dryland wheat fields.

关 键 词：夏闲期耕作 旱地小麦 土壤有机碳库 土壤温度 土壤含水量 

分 类 号：S153.6[农业科学—土壤学]