不同放牧制度对呼伦贝尔草原径流中磷流失模拟研究

发布时间：2018-09-19 17:29

【摘要】：为了探究不同放牧制度对干旱半干旱地区草原土壤磷元素流失的影响,以呼伦贝尔砂质草原为研究对象,通过设置不同降雨强度,选择自由放牧、轮牧、休牧草场进行人工模拟降雨试验,利用混合深度模型模拟磷流失过程。结果表明:在4种雨强下,自由放牧草场总磷流失量最大,是休牧草场的1.31~1.50倍,是轮牧草场的1.59~1.74倍。颗粒态磷为草场土壤磷素的主要流失形式,其含量为溶解态磷的2.2~3.7倍。混合深度模型模拟结果显示,不完全混合模型的优于完全混合模型,并且在雨强较高情况下的模拟效果较好。在雨强小于1.5mm/min降雨事件中,放牧制度对磷元素流失影响显著(p0.05),轮牧草场磷流失最少。因此,适当的将呼伦贝尔草原自由放牧草场向休牧和轮牧草场转变,将有利于减少草场磷元素流失及草原生态可持续发展。
[Abstract]:In order to investigate the effects of different grazing systems on phosphorus loss in grassland soils in arid and semi-arid areas, Hulunbeir sandy steppe was used as the research object, and free grazing and rotational grazing were selected by setting different rainfall intensity. Artificial rainfall simulation experiment was carried out on the fallow pasture, and the phosphorus loss process was simulated by the mixed depth model. The results showed that under four kinds of rain intensity, the loss of total phosphorus in free grazing pasture was the highest, 1.31 ~ 1.50 times as much as that in grazing field, and 1.59 ~ 1.74 times as much as that in rotation pasture. Granular phosphorus is the main loss form of phosphorus in grassland soil, and its content is 2.2U 3.7 times as much as dissolved phosphorus. The simulation results of the mixed depth model show that the incomplete mixing model is better than the complete mixed model, and the simulation effect is better when the rainfall intensity is high. In the event that the rainfall intensity was less than that of 1.5mm/min, the grazing system had a significant effect on phosphorus loss (p0.05), and the rotation pasture had the least phosphorus loss. Therefore, it is beneficial to reduce the loss of phosphorus and the sustainable development of grassland ecology by changing the free grazing grassland of Hulunbeir grassland to the rest grazing and rotation pasture.
【作者单位】：内蒙古农业大学水利与土木建筑工程学院;
【基金】：国家自然科学基金项目(51409288,51339002,51509133,51569019,51669022) 内蒙古农业大学优秀青年科学基金项目(2014XYQ-10)
【分类号】：S812

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