ICS 65.020.40 B64 LY 中华人民共和国林业行业标准 LY/T 3178—2020 西北华北山地次生林经营技术规程 Technical Regulation of Secondary Forest Management in the mountain areas of Northwest and North China 2020 - 03 - 30发布 2020 - 10 - 01实施 国家林业和草原局 发布 目 次 前言 ................................ ................................ ................................ ................................ ................................ .... II 1 范围 ................................ ................................ ................................ ................................ .............................. 1 2 规范性引用文件 ................................ ................................ ................................ ................................ .......... 1 3 定义和术语 ................................ ................................ ................................ ................................ .................. 1 3.1 天然林经营模式 Natural forest management models ................................ .............................. 1 3.2 林分经营 Stand - oriented management ................................ ................................ ........................... 1 3.3 林分拥挤程度 Stand crowded degree ................................ ................................ .......................... 1 3.4 幼树开敞度 The open degree of saplings ................................ ................................ .............. 1 3.5 单株木经营 Tree - orien ted management ................................ ................................ ......................... 2 3.6 针叶树为主的针阔混交林 Coniferous and broad - leaved mixed forest with coniferous - dominated ................................ ................................ ................................ ................................ ................。。。。。。以下内容略