Li Yuefen, Liu Yi, Harris Paul, Sint Hadewij, Murray Phil J, Lee Michael R F, Wu Lianhai
College of Earth Sciences, Jilin University, Changchun 130061, China; Sustainable Soils and Grassland Systems Department, Rothamsted Research, North Wyke, Okehampton, Devon EX20 2SB, UK.
Sustainable Soils and Grassland Systems Department, Rothamsted Research, North Wyke, Okehampton, Devon EX20 2SB, UK; Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.
Sci Total Environ. 2017 Dec 15;603-604:27-37. doi: 10.1016/j.scitotenv.2017.06.012. Epub 2017 Jun 12.
The North Wyke Farm Platform (NWFP) generates large volumes of temporally-indexed data that provides a valuable test-bed for agricultural mathematical models in temperate grasslands. In our study, we used the primary datasets generated from the NWFP (https://nwfp.rothamsted.ac.uk/) to validate the SPACSYS model in terms of the dynamics of water loss and forage dry matter yield estimated through cutting. The SPACSYS model is capable of simulating soil water, carbon (C) and nitrogen (N) balance in the soil-plant-atmosphere system. The validated model was then used to simulate the responses of soil water, C and N to reseeding grass cultivars with either high sugar (Lolium perenne L. cv. AberMagic) or deep rooting (Festulolium cv. Prior) traits. Simulation results demonstrated that the SPACSYS model could predict reliably soil water, C and N cycling in reseeded grassland. Compared to AberMagic, the Prior grass could fix more C in the second year following reseeding, whereas less C was lost through soil respiration in the first transition year. In comparison to the grass cultivar of the permanent pasture that existed before reseeding, both grasses reduced N losses through runoff and contributed to reducing water loss, especially Prior in relation to the latter. The SPACSYS model could predict these differences as supported by the rich dataset from the NWFP, providing a tool for future predictions on less characterized pasture.
北怀克农场平台（NWFP）生成了大量按时间索引的数据，为温带草原农业数学模型提供了一个有价值的试验平台。在我们的研究中，我们使用了从NWFP（https://nwfp.rothamsted.ac.uk/）生成的主要数据集，以通过刈割估算的水分损失和牧草干物质产量动态方面验证SPACSYS模型。SPACSYS模型能够模拟土壤-植物-大气系统中的土壤水分、碳（C）和氮（N）平衡。然后，使用经过验证的模型来模拟土壤水分、碳和氮对重新播种具有高糖（多年生黑麦草品种AberMagic）或深根（羊茅黑麦草品种Prior）特性的草品种的响应。模拟结果表明，SPACSYS模型能够可靠地预测重新播种草地中的土壤水分、碳和氮循环。与AberMagic相比，Prior草在重新播种后的第二年能够固定更多的碳，而在第一个过渡年通过土壤呼吸损失的碳较少。与重新播种前存在的永久牧场的草品种相比，两种草都减少了通过径流造成的氮损失，并有助于减少水分损失，特别是Prior相对于后者而言。正如NWFP丰富的数据集所支持的那样，SPACSYS模型能够预测这些差异，为未来对特征较少的牧场进行预测提供了一个工具。
