ABSTRACT

Gridded model assessments require at least one climatic and one soil database for carrying out the simulations. There are several parallel soil and climate database development projects that provide sufficient, albeit considerably different, observation based input data for crop model based impact studies. The input database related uncertainty of the Biome-BGCMuSo agro-environmental model outputs was investigated using three and four different gridded climatic and soil databases, respectively covering an area of nearly 100.000 km² with 1104 grid cells. Spatial, temporal, climate and soil database selection related variances were calculated and compared for four model outputs obtained from 30-year-long simulations. The choice of the input database introduced model output variability that was comparable to the variability the year-to-year change of the weather or the spatial heterogeneity of the soil causes. Input database selection could be a decisive factor in carbon sequestration related studies as the soil carbon stock change estimates may either suggest that the simulated ecosystem is a carbon sink or to the contrary a carbon source on the long run. Careful evaluation of the input database quality seems to be an inevitable and highly relevant step towards more realistic plant production and carbon balance simulations.

摘要

网格模型评估至少需要一个气候数据库和一个土壤数据库来进行模拟。有几个并行的土壤和气候数据库开发项目为基于作物模型的影响研究提供了充足的、尽管有很大不同的基于观测的输入数据。使用三个和四个不同的网格气候和土壤数据库对 Biome-BGCMuSo 农业环境模型输出的输入数据库相关不确定性进行了调查，分别覆盖了近 100.000 km ²的区域有 1104 个网格单元。计算并比较了从 30 年模拟中获得的四个模型输出的空间、时间、气候和土壤数据库选择相关的方差。输入数据库的选择引入了模型输出可变性，该可变性与天气的逐年变化或土壤原因的空间异质性的可变性相当。输入数据库的选择可能是碳固存相关研究的决定性因素，因为土壤碳储量变化估计可能表明模拟生态系统是碳汇，或者相反，从长远来看，它是碳源。对输入数据库质量的仔细评估似乎是实现更现实的植物生产和碳平衡模拟的不可避免且高度相关的步骤。