Dar Javid Ahmad, Ganie Khursheed Ahmad, Sundarapandian Somaiah
Department of Ecology and Environmental Sciences, School of Life Sciences, Pondicherry University, Puducherry, 605014, India.
Department of Botany, Islamia College of Science and Commerce, Srinagar, India.
Environ Monit Assess. 2015 Nov;187(11):715. doi: 10.1007/s10661-015-4927-2. Epub 2015 Oct 29.
Soil CO2 efflux was measured in four different coniferous forest types (Cedrus deodara (CD), Pinus wallichiana (PW), mixed coniferous (MC), and Abies pindrow (AP)) for a period of 2 years (April 2012 to December 2013). The monthly soil CO2 efflux ranged from 0.8 to 4.1 μmoles CO2 m(-2) s(-1) in 2012 and 1.01 to 5.48 μmoles CO2 m(-2) s(-1) in 2013. The soil CO2 efflux rate was highest in PW forest type in both the years, while it was lowest in MC and CD forest types during 2012 and 2013, respectively. Soil temperature (TS) at a depth of 10 cm ranged from 3.8 to 19.4 °C in 2012 and 3.5 to 19.1 °C in 2013 in all the four forest types. Soil moisture (MS) ranged from 19.8 to 58.6% in 2012 and 18.5 to 58.6% in 2013. Soil CO2 efflux rate was found to be significantly higher in summer than the other seasons and least during winter. Soil CO2 efflux showed a significant positive relationship with TS (R2=0.52 to 0.74), SOC% (R2=0.67), pH (R2=0.68), and shrub biomass (R2=0.51), whereas, only a weak positive relationship was found with soil moisture (R2=0.16 to 0.41), tree density (R2=0.25), tree basal area (R2=0.01), tree biomass (R2=0.07), herb biomass (R2=0.01), and forest floor litter (R2=0.02). Thus, the study indicates that soil CO2 efflux in high mountainous areas is greatly influenced by seasons, soil temperature, and other environmental factors.
在4种不同的针叶林类型（雪松（CD）、华山松（PW）、混交针叶林（MC）和喜马拉雅冷杉（AP））中测量了2年（2012年4月至2013年12月）的土壤二氧化碳通量。2012年每月土壤二氧化碳通量范围为0.8至4.1微摩尔二氧化碳·米-2·秒-1，2013年为1.01至5.48微摩尔二氧化碳·米-2·秒-1。这两年中，土壤二氧化碳通量率在PW林型中最高，而在2012年和2013年分别在MC和CD林型中最低。在所有4种森林类型中，2012年10厘米深度处的土壤温度（TS）范围为3.8至19.4°C，2013年为3.5至19.1°C。土壤湿度（MS）在2012年范围为19.8%至58.6%，2013年为18.5%至58.6%。发现土壤二氧化碳通量率在夏季显著高于其他季节，在冬季最低。土壤二氧化碳通量与TS（R2 = 0.52至0.74）、土壤有机碳百分比（R2 = 0.67）、pH（R2 = 0.68）和灌木生物量（R2 = 0.51）呈显著正相关，而与土壤湿度（R2 = 0.16至0.41）、树木密度（R2 = 0.25）、树木基部面积（R2 = 0.01）、树木生物量（R2 = 0.07）、草本生物量（R2 = 0.01）和林地凋落物（R2 = 0.02）仅呈弱正相关。因此，该研究表明，高山区的土壤二氧化碳通量受季节、土壤温度和其他环境因素的影响很大。
