Data from: Carbon stocks in the Guinea savanna of Ghana: estimates from three protected areas

Savannas are widespread in sub-Saharan Africa (SSA) and unarguably play major role in the global carbon balance. Extensive quantification of carbon stocks of the savannas in SSA will therefore contribute significantly to the global carbon budget in the era of climate change. In this study, we investigated the spatial distribution of carbon stocks of different soil fractions from the dominant tree species (Vitellaria paradoxa) of three forest reserves in the Guinea savanna of Ghana as well as the tree and non-tree carbon stocks. The study was carried out in Kenikeni, Sinsablegbinni and Klupene forest reserves using nested plot design. Higher soil carbon stock (SCS) was associated with the silt +clay fraction than the microaggregates and small macroaggregates of all three protected areas. Soil carbon stocks ranged from 2.99 to 15.89 Mg C /ha in the surface soil of 0-10 cm depth. The highest SCS was recorded at the sub-canopy (SC), drip line (DL) and 2(SC + DL) zones from the dominant tree of the Klupene, Sinsablegbinni and Kenikeni forest reserves, respectively. The highest tree carbon stock of 60.57 Mg C/ha was recorded in Kenikeni as compared to 26.98 Mg C/ha of Sinsablegbinni, which had the highest stocking density. Average carbon capture by a single tree ranged from 0.04 to 0.34 Mg C. Grass C stock in the above- ground biomass ranged from 0.09 to 0.29 Mg C /ha whilst the below ground carbon stock ranged from 0.03 to 0.44 Mg C /ha. Accumulation of carbon in the aboveground grass biomass increased with decreasing forest cover, whereas that of the below ground biomass increased with increasing forest cover with implications for forest management in the savanna.

稀树草原（Savannas）广泛分布于撒哈拉以南非洲（sub-Saharan Africa, SSA），无疑在全球碳平衡中发挥着关键作用。在气候变化时代，对撒哈拉以南非洲稀树草原的碳储量开展全面量化研究，将对全球碳预算作出重要贡献。本研究以加纳几内亚稀树草原区域3处森林保护区内的优势树种乳木果（Vitellaria paradoxa）为研究对象，调查了其不同土壤组分的碳储量空间分布特征，同时分析了树木碳储量与非树木碳储量。研究采用嵌套样地设计（nested plot design），在凯尼肯尼（Kenikeni）、辛萨布勒格宾尼（Sinsablegbinni）和克鲁佩内（Klupene）3处森林保护区内实施。相较于3处保护区的微团聚体与小型大团聚体组分，粉粒+黏粒组分的土壤碳储量（soil carbon stock, SCS）更高。0-10 cm表层土壤的土壤碳储量范围为2.99~15.89 Mg C/ha。克鲁佩内、辛萨布勒格宾尼和凯尼肯尼3处森林保护区的最高土壤碳储量，分别出现在优势树木的冠下区（sub-canopy, SC）、滴水线区（drip line, DL）以及冠下区+滴水线区2倍范围（2(SC + DL)）。凯尼肯尼保护区的树木碳储量最高，达60.57 Mg C/ha；辛萨布勒格宾尼保护区的立木密度最高，其树木碳储量为26.98 Mg C/ha。单棵树木的平均固碳量范围为0.04~0.34 Mg C。地上生物量中的草本碳储量范围为0.09~0.29 Mg C/ha，地下碳储量范围为0.03~0.44 Mg C/ha。地上草本生物量的碳积累量随森林覆盖率降低而升高，而地下生物量的碳积累量则随森林覆盖率升高而增加，该结果对稀树草原的森林管理具有重要指导意义。