STUDY ON FLUXES OF CH4 EMISSION FROM PADDY FIELDS IN CHANGCHUN AREA

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.

Evaluation of a new frequency-volume chart for children with primary monosymptomatic nocturnal enuresis:a prospective,comparative study

Introduction To improve compliance with voiding diaries in children with primary monosymptomatic nocturnal enuresis(PMNE),a new modified 3-day weekend frequency-volume chart(FVC)was designed,and the compliance and validity of this modified FVC was evaluated by comparing with the International Children's Continence Society(ICCS)recommended voiding diary.Methods A total of 1200 patients with PMNE were enrolled in the study from 13 centers in China and were randomly assigned to record this modified FVC or the ICCS-recommended voiding diary.The primary outcome measure was the compliance,assessed by comparing the completing index and the quality score of diaries between two groups.The secondary outcome measure was the validity,evaluated by comparing the constituent of subtypes,micturition parameters and response rate to desmopressin.Results Among the 1200 participants enrolled in the study,447 patients completed the ICCS-recommended voiding diary and 469 completed the modified diary.The diurnal completing index and the quality score of the modified FVC group were better than those of the ICCS group.In addition,there was no significant difference between these two groups in the subtype classification,or in the response rate to desmopressin.Conclusions The modified FVC could be applied to obtain the voiding characteristics of children with PMNE as the ICCS-recommended voiding diary does and offers a reasonable and better choice for children with PMNE from the unselected population in the future.