干扰我国人工草地生态系统的主要影响因素研究

Research on the Main Factors on the Ecosystem of Artificial Grassland in China

[目的]明确影响人工草地生态系统的关键因素。[方法]在参阅大量前人研究工作基础上,从播种方式、放牧强度、种植时限和施肥4个方面进行总结分析它们对人工草地生态系统的影响。[结果]混播方式比单播方式更有利于资源利用率和生态系统健康,而单播或隔行混播对增加土壤有机碳要比同行混播更为有利,同时隔行混播的草地产生的牧草产量要大于同行混播的草地,牧草产量最低的为单播草地;轻度和中度放牧有利于维持牧草的高产和高质以及草地的可持续发展,重度放牧则导致草地的退化;种植时限对植被群落结构和土壤理化性质的影响则具明显区域差异;长期施肥可有效提高土壤的有机碳含量以及牧草的产量和质量,但确定特定区域特定牧草的施肥量、施肥类型和比例是施肥效应发挥作用的关键。[结论]在进行人工草地种植时,要合理利用各因素的正面效应,有效控制人为干扰的深度和广度,避免或减弱负面作用的影响,为人工草地的高产、稳产打下良好的基础。

[Objective] In order to achieve high quality and productivity of artificial grassland,it is necessary to explore main factors,which highly influence the grassland ecosystem.[Methods] Based on former studies,this paper assessed the impacts of different factors such as sowing types,grazing intensity,planting period and fertilization on the vegetation community and soil physical and chemical characteristics of the artificial grassland in China.[Results] The results indicated that： mixed sowing is superior to single sowing when considering improving resources utility and ecosystem health;single seeding or inter-line mixed sowing are superior to one-lie sowing when considering increasing soil organic carbon;the sequence for different sowing types to enhance grassland production is： inter-line mixed sowing one-line sowing single sowing.When considering grazing intensity,it is assumed that grazing with light and median intensity is superior to maintain high productivity and high quality of forbs,and sustainability development of grassland.Heavy grazing intensity may lead to grassland degradation.The impacts of planting periods on vegetation community and soil characteristics are different in different areas.Furthermore,long-term fertilization can effectively increase the content of soil organic carbon and enhance the productivity and quality of forbs.However,defining the amount,types and their proportions of fertilizers are keys to gain the benefits of fertilization.[Conclusions] The scientific proposals on the depth and width of reasonable control of artificial interruption were offered,to lead to the positive effects on the vegetation community and soil physical and chemical characteristics.