草地生产与生态功能合理配置的理论基础与关键技术

草地生产功能和生态功能的合理配置对于生态草业的可持续发展至关重要.本文总结了国内外草业发展现状,特别是我国草地经营管理中存在的主要问题;介绍了草地生产与生态功能合理配置的6个基础理论:放牧优化假说、中度干扰假说、放牧促进/减缓生态系统养分循环假说、草畜平衡理论和草地农业系统理论.在分析生态草业发展面临的主要技术瓶颈基础上,提出了生态草业建设的核心技术体系,着重介绍了退化草地恢复与培育的4项技术、天然草地保护与合理利用的2项技术,以及人工草地建设与管理的技术.最后介绍了天然草地和人工草地配置的原则,以及人工草地的类型选择与合理布局的技术.所述理论和技术对于指导我国生态草业建设和可持续发展具有重要指导意义

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^