利用红外气体箱式法(Infrared Gas Analyze,IRGA),于2008年8月晴天对福州市马尼拉草坪(Zoysia matrel-la)的生态系统CO2净交换(NEE)和环境因子进行观测,阐明NEE及其组分的昼夜动态变化特征和影响因子。马尼拉草坪NEE的昼夜变化呈现为单...利用红外气体箱式法(Infrared Gas Analyze,IRGA),于2008年8月晴天对福州市马尼拉草坪(Zoysia matrel-la)的生态系统CO2净交换(NEE)和环境因子进行观测,阐明NEE及其组分的昼夜动态变化特征和影响因子。马尼拉草坪NEE的昼夜变化呈现为单峰型曲线,昼间其变化规律较强,夜间呈波动状态。NEE(取绝对值)最大值出现在10:00,最小值出现在16:00左右。太阳辐射、腔室内空气相对湿度和气温与NEE的相关性均为极显著(p<0.01),太阳辐射、腔室内空气相对湿度和5cm土壤温度共同解释NEE速率昼夜变异的89.30%。太阳辐射和腔室内空气相对湿度是影响草坪生态系统CO2净交换量日动态的主导环境因子;其中,太阳辐射可以单独解释NEE速率昼夜变化的79.70%,腔室内空气相对湿度可以单独解释NEE速率昼夜变化的50.40%;夏季晴天草坪生态系统在日尺度上表现为净吸收,平均CO2净交换速率为-4.11μmol/(m2.s)(负值表示吸收),平均日总通量为-0.18 mol/(m2.d)。展开更多
To provide potential implications of species selection for carbon plantation, differences in carbon sequestration pattern and net ecosystem production (NEP) were determined between two 36-year-old plantations of broad...To provide potential implications of species selection for carbon plantation, differences in carbon sequestration pattern and net ecosystem production (NEP) were determined between two 36-year-old plantations of broadleaved species, Castanopsis kawakamii and Cunninghamia lanceolata, in Sanming, Fujian. Annual net carbon sequestration was 13.639 and 6.599 t C·hm -2 a -1 , respectively, in the C. kawakamii and the C. lanceolata, among which the annual biomass C increment and the litterfall production was evenly distributed. To the annual net carbon sequestration, the contribution of stem (wood plus bark) increment was much lower, and that of branch increment was much higher in the C. kawakamii than in the C. lanceolata (26.6% versus 40.3%, and 11.5% versus 0.3%). In both plantation, the above and belowground litterfall accounted 60% and 40% respectively for the annual litterfall production, which was estimated 7.183 t C·hm -2 a -1 in the C. kawakamii and 3.554 t C·hm -2 a -1 in the C. lanceolata. Annual soil heterotrophic respiration was responsible for a C loss of 5.983 and 2.984 t·hm -2 a -1 from soil to atmosphere in the C. kawakamii and the C. lanceolata, respectively. Carbon balance analysis showed there were a positive net ecosystem production (C sink), 7.656 and 3.615 t C·hm -2 a -1 , for the C. kawakamii and the C. lanceolata, respectively. For the purpose of carbon management, C. kawakamii might be a more suitable species than C. lanceolata in local region.展开更多
文摘利用红外气体箱式法(Infrared Gas Analyze,IRGA),于2008年8月晴天对福州市马尼拉草坪(Zoysia matrel-la)的生态系统CO2净交换(NEE)和环境因子进行观测,阐明NEE及其组分的昼夜动态变化特征和影响因子。马尼拉草坪NEE的昼夜变化呈现为单峰型曲线,昼间其变化规律较强,夜间呈波动状态。NEE(取绝对值)最大值出现在10:00,最小值出现在16:00左右。太阳辐射、腔室内空气相对湿度和气温与NEE的相关性均为极显著(p<0.01),太阳辐射、腔室内空气相对湿度和5cm土壤温度共同解释NEE速率昼夜变异的89.30%。太阳辐射和腔室内空气相对湿度是影响草坪生态系统CO2净交换量日动态的主导环境因子;其中,太阳辐射可以单独解释NEE速率昼夜变化的79.70%,腔室内空气相对湿度可以单独解释NEE速率昼夜变化的50.40%;夏季晴天草坪生态系统在日尺度上表现为净吸收,平均CO2净交换速率为-4.11μmol/(m2.s)(负值表示吸收),平均日总通量为-0.18 mol/(m2.d)。
文摘To provide potential implications of species selection for carbon plantation, differences in carbon sequestration pattern and net ecosystem production (NEP) were determined between two 36-year-old plantations of broadleaved species, Castanopsis kawakamii and Cunninghamia lanceolata, in Sanming, Fujian. Annual net carbon sequestration was 13.639 and 6.599 t C·hm -2 a -1 , respectively, in the C. kawakamii and the C. lanceolata, among which the annual biomass C increment and the litterfall production was evenly distributed. To the annual net carbon sequestration, the contribution of stem (wood plus bark) increment was much lower, and that of branch increment was much higher in the C. kawakamii than in the C. lanceolata (26.6% versus 40.3%, and 11.5% versus 0.3%). In both plantation, the above and belowground litterfall accounted 60% and 40% respectively for the annual litterfall production, which was estimated 7.183 t C·hm -2 a -1 in the C. kawakamii and 3.554 t C·hm -2 a -1 in the C. lanceolata. Annual soil heterotrophic respiration was responsible for a C loss of 5.983 and 2.984 t·hm -2 a -1 from soil to atmosphere in the C. kawakamii and the C. lanceolata, respectively. Carbon balance analysis showed there were a positive net ecosystem production (C sink), 7.656 and 3.615 t C·hm -2 a -1 , for the C. kawakamii and the C. lanceolata, respectively. For the purpose of carbon management, C. kawakamii might be a more suitable species than C. lanceolata in local region.
