作物生长与气候的互馈是当前气候变化研究的热点之一。陆面模型作为一项重要的研究工具,其模型框架、算法设计及参数化方案的不同会直接导致模拟结果的不确定性。为探究陆面模型DLM(dynamic land model)和CLM5(community land model)在作物生长及农田热通量模拟方面的差异及原因,评估2个模型在华北平原作物研究中的适用程度,论文开展了冬小麦—夏玉米轮作站点的模拟对比研究。结果显示,DLM的夏玉米叶面积指数和生态系统总初级生产力的模拟值更高,与观测值更为接近;CLM5模型则在冬小麦模拟中略优。DLM的潜热模拟值与观测值的相关性普遍更高,可能反映了DLM采用的彭曼公式、双叶策略比CLM5采用基于水势梯度质量守恒、大叶策略的潜热计算方法更具优势。对于产量,模型当前的估测能力并不理想。总的来说,在默认设定下,2个模型的模拟结果能基本反映研究区农田站点内夏玉米和冬小麦的生长规律,但与实测值存在一定偏差。模型在该区域的适用性可能需要通过添加农田管理措施、算法优化和参数本地化等方式进一步提高。 相似文献
The present study investigates the isospin and Z‐dependency of the effective symmetry energy and its co‐efficient, namely, neutron pressure for the isotonic chain of neutron magic N = 40, and 82. The relativistic mean‐field model with the non‐linear NL3* parameter and Relativistic‐Hartree‐Bogoliubov approach with density‐dependent DD‐ME2 parameter sets are used for the analysis. The coherent density fluctuation model and Liquid‐Drop‐Approximation are adopted to formulate the nuclear matter observables such as symmetry energy, neutron pressure of finite nuclei at local density. We found a notable sign of the shell/sub‐shell closure following the proton magic over the isotonic chain. Further, a comparative analysis shows that the coherent density fluctuation model is a better approximation to include the surface effect of finite nuclei as compared to the Liquid‐Drop‐Approximation, which plays a significant role to determine the shell/sub‐shell closure over an isotopic and/or isotonic chain. 相似文献
