State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, No. 19, XinJieKouWai Street, HaiDian District, Beijing, 100875, People's Republic of China,
Environ Monit Assess. 2014 Jan;186(1):135-49. doi: 10.1007/s10661-013-3361-6. Epub 2013 Aug 8.
Climate changes may have immediate implications for forest productivity and may produce dramatic shifts in tree species distributions in the future. Quantifying these implications is significant for both scientists and managers. Cunninghamia lanceolata is an important coniferous timber species due to its fast growth and wide distribution in China. This paper proposes a methodology aiming at enhancing the distribution and productivity of C. lanceolata against a background of climate change. First, we simulated the potential distributions and establishment probabilities of C. lanceolata based on a species distribution model. Second, a process-based model, the PnET-II model, was calibrated and its parameterization of water balance improved. Finally, the improved PnET-II model was used to simulate the net primary productivity (NPP) of C. lanceolata. The simulated NPP and potential distribution were combined to produce an integrated indicator, the estimated total NPP, which serves to comprehensively characterize the productivity of the forest under climate change. The results of the analysis showed that (1) the distribution of C. lanceolata will increase in central China, but the mean probability of establishment will decrease in the 2050s; (2) the PnET-II model was improved, calibrated, and successfully validated for the simulation of the NPP of C. lanceolata in China; and (3) all scenarios predicted a reduction in total NPP in the 2050s, with a markedly lower reduction under the a2 scenario than under the b2 scenario. The changes in NPP suggested that forest productivity will show a large decrease in southern China and a mild increase in central China. All of these findings could improve our understanding of the impact of climate change on forest ecosystem structure and function and could provide a basis for policy-makers to apply adaptive measures and overcome the unfavorable influences of climate change.
气候变化可能会对森林生产力产生直接影响，并可能导致未来树种分布发生剧烈变化。量化这些影响对科学家和管理者都具有重要意义。杉木是一种重要的针叶木材树种，因其在中国的快速生长和广泛分布而受到重视。本文提出了一种方法，旨在增强杉木在气候变化背景下的分布和生产力。首先，我们基于物种分布模型模拟了杉木的潜在分布和建立概率。其次，校准了一个基于过程的模型 PnET-II 模型，并改进了其水量平衡的参数化。最后，利用改进后的 PnET-II 模型模拟了杉木的净初级生产力（NPP）。将模拟的 NPP 和潜在分布结合起来，生成一个综合指标，即估计总 NPP，用于综合描述森林在气候变化下的生产力。分析结果表明：（1）杉木的分布在中国中部将增加，但在 2050 年代建立的平均概率将降低；（2）改进、校准和成功验证了 PnET-II 模型，用于模拟中国杉木的 NPP；（3）所有情景都预测 2050 年代总 NPP 将减少，而 a2 情景下的减少幅度明显低于 b2 情景。NPP 的变化表明，森林生产力将在中国南部大幅下降，在中部略有增加。所有这些发现都可以提高我们对气候变化对森林生态系统结构和功能影响的认识，并为决策者提供依据，以采取适应措施，克服气候变化的不利影响。
