摘要
冻融是我国季节性冻土区重要的自然环境特征,冻融过程中土壤水热变化影响着生态系统的功能。本文利用长期定位试验,监测对比分析了东北典型黑土冻融过程中,传统耕作、草地和裸地3种土地利用方式下黑土水热动态变化规律。结果表明:观测期内,月尺度和日尺度上土壤温度、液态含水量和电导率变化趋势基本一致。不同冻融阶段,土壤温度表现为解冻期>始冻期>完全冻结期,土壤液态含水量表现为始冻期≈解冻期>完全冻结期,土壤电导率表现为始冻期>解冻期>完全冻结期。对于不同土地利用方式,土壤温度在各冻融阶段均表现为裸地>草地>传统耕作。在始冻期,土壤液态含水量和电导率均表现为裸地>传统耕作>草地。在完全冻结期,土壤液态含水量表现为传统耕作>裸地>草地,土壤电导率表现为裸地>传统耕作>草地。在解冻期,土壤液态含水量表现为草地>传统耕作>裸地,土壤电导率表现为传统耕作>草地>裸地。
Soil thawing -freezing process is one of the important environment characteristics in the seasonal frozen soil regions, and the dynamies of soil water and soil temperature ilffluenees ecosystem functions. Based on a longterm field experiment, the variations of soil water, temperature and electrical conductivity under conventional tillage, grassland and bare land were observed and analyzed dur- ing the thawing -freezing process in a typical Mollisols of China. Results showed that the dynamies of soil water, temperature and elec- trical conductivity was similar at daily and monthly scale during the observation period. In different freezing - thawing periods, soil tem- perature decreased in the order of thawing period, freezing period and frozen period. Soil water content in thawing period and freezing period was greater than that in frozen period, respectively. Soil electrical conductivity decreased in the order of freezing period, tha- wing period and frozen period. For different land use types, soil temperature decreased in the order of bare land, grassland and con- ventional tillage. During freezing period, both soil water content and soil electrical conductivity decreased was in the order of bare land, conventional tillage and grassland, respectively. During frozen period, soil water content decreased in the order of conventional tillage, bare land and grassland ; soil electrical conductivity decreased in the order of bare land, conventional tillage and grassland. During tha- wing period, soil water content decreased in the order of grassland, conventional tillage and bare land; soil electrical conductivity de- creased in the order of conventional tillage, grassland and bare land.
作者
胡伟
张兴义
严月
HU Wei;ZHANG Xingyi;YAN Yue(Key Laboratory of Mollisols Agroecology,Northeast Institute of Geography and Agroecology,CAS,Harbin 150081,China)
出处
《土壤与作物》
2018年第3期312-323,共12页
Soils and Crops
基金
国家重点研发计划项目(2017YFC0504200)
国家自然科学基金项目(41701313)
关键词
黑土
冻融过程
土地利用方式
土壤温度
土壤液态含水量
土壤电导率
Mollisols
freezing - thawing process
land use types
soil temperature
soil water content
soil electrical conductivity
