生态环境学报Issue(11)：1791-1798,8.DOI:10.16258/j.cnki.1674-5906.2015.11.006
华北低山丘陵区人工林土壤CH4通量测定代表性时段研究
Representative Time Periods of Measuring Daily CH4 Fluxes of Soil in Robinia psedudoacia Plantation in Low Hilly Areas of North China
摘要
Abstract
A proper period of time on a day should be chose to measure CH4 flux, and to take the measured average value to represent the daily average CH4 fluxes. The short-term observed soil CH4 flux data can also be effectively applied in the estimation of CH4 fluxes at a longer time scale. In this study, we used an automatic observation system of soil CH4 to collect the continuous day and night observational data inRobinia pseudoacaciaL. plantation in low hilly areas of north China in November 2014 to October 2015. We obtained a total of 140 days of continuous data in growing season of May 2015 to October 2015 (82 days) and non-growing season of November 2014 to April 2015 (58 days). The mean daily variation of CH4 flux was analyzed, and the relative percentage differences between the representative time and daily average in each month was calculated to select a time period which were within a relative percentage difference of ± 10% as the representative period. After the confirmation of the representative period, the mean CH4 fluxes of soil between the representative time periods and daily was fitted, and the effectiveness of its annual scale was estimated and evaluated. The results show that: (1) the change range of the mean daily variation was -0.74~-1.16, -0.58~-0.79, -0.48~-0.67, -0.55~-0.86, -0.59~-1.49, -0.60~-0.72, -0.70~-0.80, -0.50~-0.66, -0.54~-0.71, -0.71~-0.85 and -0.84~-1.09 nmol·m-2·s-1, and the diurnal range was 0.42, 0.21, 0.19, 0.31, 0.90, 0.12 , 0.10, 0.16, 0.17, 0.15 and 0.24 nmol·m-2·s-1 in each month, respectively; (2) the period of 8: 00─9: 00 was selected as the representative time in growing season; and 9: 00─10: 00 as the representative time in non-growing season; (3) The relative difference between the CH4 fluxes of the representative period and daily average were 5.71% (forward), 4.50% (forward), -1.98% (negative), 3.11% (forward), 6.34% (forward), -7.37% (negative), -1.23% (negative), -9.03% (negative), -4.43% (negative), -0.71% (negative), 4.97% (forward) they were all within ± 10% in each months, respectively; (4) the fit result between the soil CH4 flux of daily averages and the representative time showed that the minimum data of the difference of CH4 flux appeared in September while the maximum appeared in July; (5) the selected representative period can represent the annual CH4 flux of this study area (r2=0.885,P=0.000) when we accumulate soil CH4 flux of selected representative period to annual scale.关键词
代表性/CH4通量/季节尺度/时段Key words
representative/methane/season scale/period分类
农业科技引用本文复制引用
庄静静,张劲松,孟平,郑宁,贾长荣,李剑侠,李建中..华北低山丘陵区人工林土壤CH4通量测定代表性时段研究[J].生态环境学报,2015,(11):1791-1798,8.基金项目
国家林业公益性行业科研项目（201404206）；中国林科院林业所所基金项目 （）
