The study on soil thermal conductivity (STC) was an important side of research on ground source heat pump technique,geological disposal of high-level radioactive wastes,heat distribution of buried cable. Especially ow...The study on soil thermal conductivity (STC) was an important side of research on ground source heat pump technique,geological disposal of high-level radioactive wastes,heat distribution of buried cable. Especially owing to technical requirement for shallow terrestrial heat recently, it directly influenced the design and solution in engineering problems. The authors measured the STC in the studied area with QTM-D2 and discussed the effect of samples in size, the measurement error between the samples in lab and in site. The results indicate measuring STC by heat pole method with less influence upon the samples in size, and measuring results on the different geometry size approach very much. The STC is fit for the empirical relation between the temperature and TC under the condition of normal temperature. It is significance for understanding STC in northern China and simulation of temperature field.展开更多
Little has been done in measurement and research of the flux of CH4 emission from paddy fields in Changchun area, Jilin Province, China before 1994. So the purpose of the study is to offer available regional data of C...Little has been done in measurement and research of the flux of CH4 emission from paddy fields in Changchun area, Jilin Province, China before 1994. So the purpose of the study is to offer available regional data of CH4 emission flux and to discuss the factors which affect CH4 emission from paddy fields. Experimental paddy fields are chosen using TM pictures respectively in Xinlicheng (43° 49′ N, 125° 20′ E) of the Yitong River’s and in Wanchang (43° 44′ 10″ N, 125° 53′ 11″ E) of the Yinma River’s alluvial plain. The fluxes of CH4 emission from paddy fields are measured by the method of static chamber in Changchun area in 3 consecutive years. The research results show that the peak of CH4 emission from paddy fields occurs during the booting stage. The mean fluxes of CH4 emission are 7.056 mg/(m2· h) and 0.489 mg/(m2· h) in the paddy fields of flood and discontinuous irrigation respectively. The contrastive study holds that climate condition, the way of water management and fertilizer variation have significant influence on fluxes of CH4 emission from paddy fields. The difference of climatic conditions causes the interannual change of the flux of CH4 emission from paddy fields. In general, the flux of CH4 emission from paddy fields of flood irrigation is greater than that from paddy fields of discontinuous irrigation. To change the way of water management perhaps is an available way to reduce CH4 emission flux from paddy fields.展开更多
文摘The study on soil thermal conductivity (STC) was an important side of research on ground source heat pump technique,geological disposal of high-level radioactive wastes,heat distribution of buried cable. Especially owing to technical requirement for shallow terrestrial heat recently, it directly influenced the design and solution in engineering problems. The authors measured the STC in the studied area with QTM-D2 and discussed the effect of samples in size, the measurement error between the samples in lab and in site. The results indicate measuring STC by heat pole method with less influence upon the samples in size, and measuring results on the different geometry size approach very much. The STC is fit for the empirical relation between the temperature and TC under the condition of normal temperature. It is significance for understanding STC in northern China and simulation of temperature field.
基金Under the auspices of Jilin Commttee of Science and Technology (grant 963416- 1), and Changchun Jingyuetan Remote Sensing Test
文摘Little has been done in measurement and research of the flux of CH4 emission from paddy fields in Changchun area, Jilin Province, China before 1994. So the purpose of the study is to offer available regional data of CH4 emission flux and to discuss the factors which affect CH4 emission from paddy fields. Experimental paddy fields are chosen using TM pictures respectively in Xinlicheng (43° 49′ N, 125° 20′ E) of the Yitong River’s and in Wanchang (43° 44′ 10″ N, 125° 53′ 11″ E) of the Yinma River’s alluvial plain. The fluxes of CH4 emission from paddy fields are measured by the method of static chamber in Changchun area in 3 consecutive years. The research results show that the peak of CH4 emission from paddy fields occurs during the booting stage. The mean fluxes of CH4 emission are 7.056 mg/(m2· h) and 0.489 mg/(m2· h) in the paddy fields of flood and discontinuous irrigation respectively. The contrastive study holds that climate condition, the way of water management and fertilizer variation have significant influence on fluxes of CH4 emission from paddy fields. The difference of climatic conditions causes the interannual change of the flux of CH4 emission from paddy fields. In general, the flux of CH4 emission from paddy fields of flood irrigation is greater than that from paddy fields of discontinuous irrigation. To change the way of water management perhaps is an available way to reduce CH4 emission flux from paddy fields.
