Forests play an important role in mitigating climate change by absorbing carbon from atmosphere. The global forests sequestrated 2.4±0.4 Pg C y^-1 from 1990 to 2007, while the quantitative assessment on the carbon sequestration potential （CSP） of global forests has much uncertainty. We collected and compiled a database of site above-ground biomass （AGB） of global mature forests, and obtained AGB carbon carrying capacity （CCC） of global forests by interpolating global mature forest site data. The results show that： （i） at a global scale, the AGB of mature forests decline mainly from tropical forests to boreal forests, and the maximum AGB occurs in middle latitude regions; （ii） temperature and precipitation are main factors influencing the AGB of mature forests; and （iii） the above-ground biomass CCC of global forests is about 586.2±49.3 Pg C, and with CSP of 313.4 Pg C. Therefore, achieving CCC of the existing forests by reducing human disturbance is an option for mitigating greenhouse gas emission.
根据野外调查和实验分析研究了江西省千烟洲人工针叶林下狗脊蕨(Woodwardia japonica)群落的生物量、细根生物量、净初级生产力(Net primary productivity,NPP)、比叶面积(Specific leaf area,SLA)和叶面积指数(Leaf area index,LAI)等。通过叶片参数和地上生物量的相关关系建立了狗脊蕨单株地上生物量估算模型,分别为W1=0.021H1.545(R2=0.790)和W1=2.518(D2H)0.616(R2=0.894;H为株高,D为地径)。人工针叶林下灌草层地上生物量为367.8g.m-2(52～932g.m-2),凋落物为1631g.m-2(672～2763g.m-2),分别占乔木层地上生物量的4.7%(1.55%～13.2%)和20.7%(7.6%～32.1%)。狗脊蕨群落地上生物量和NPP分别为266.6g.m-2和88.67g.m-2.a-1,其中狗脊蕨种群占73.7%;地下生物量为212.6g.m-2。狗脊蕨的SLA和叶干物质含量(Leaves day mutter con-tent,LDMC)分别为144.0cm2.g-1和31.99%,二者之间呈显著负相关;最佳叶面积估算模型为S=21.9226-0.152L2+0.0009L3(9.0≤L(叶片长度)≤23.5;1.4≤W(叶片宽度)≤5.9)。狗脊蕨种群的LAI为1.8。土壤含水量对狗脊蕨生物量有显著影响。群落生物量与土壤有机质和全氮含量正相关。
