青海三江源地区三种天然圆柏林更新特征  

Regeneration characteristics of three natural Juniperus forests in the Three-River Headwater Region of Qinghai Province,China

作　　者：黄婷 郝家田 杜一尘 田翠翠 张婧 王海 侯琳[1] HUANG Ting;HAO Jia-tian;DU Yi-chen;TIAN Cui-cui;ZHANG Jing;WANG Hai;HOU Lin(College of Forestry,Northwest A&F University,Yangling 712100,Shaanxi,China;Northwest Surveying,Planning and Designing Institute of National Forestry and Grassland Administration,Xi’an 710048,China)

机构地区：[1]西北农林科技大学林学院,陕西杨凌712100 [2]国家林业和草原局西北调查规划设计院,西安710048

出　　处：《应用生态学报》2022年第2期297-303,共7页Chinese Journal of Applied Ecology

基　　金：国家林业和草原局西北调查规划设计院科研项目(K4030218362,LC-2-12)资助。

摘　　要：为明确青海三江源地区3种天然圆柏林的更新特征及其主导影响因子,对天然林保护与经营提供参考,本研究评价了圆柏林天然更新等级,分析了林分因子和林地土壤因子对圆柏林天然更新的影响。结果表明:3种天然圆柏林更新不良,更新潜力不足。大果圆柏林、祁连圆柏林和密枝圆柏林平均更新密度分别为332、279和202株·hm^(-2),更新个体的高度集中在1~3 m。大果圆柏林下有极少量幼苗存在,数量为12株·hm^(-2),密枝圆柏林和祁连圆柏林下无幼苗存在。大果圆柏林更新密度与林分密度、林地土壤有机质和有效磷均呈显著正相关,与灌木盖度呈显著负相关;密枝圆柏林更新密度与草本盖度、人为干扰度、林地坡度和林地土壤全氮均呈显著负相关,与土壤含水率呈显著正相关;祁连圆柏林更新密度与林分密度、林地土壤速效钾和有效磷均呈显著正相关,与草本盖度呈显著负相关。多元回归分析显示,大果圆柏林更新主要受林下灌木盖度和林地土壤有效磷影响;密枝圆柏林更新主要受林下草本盖度、林地土壤全氮和人为干扰影响;祁连圆柏林更新主要受林下草本盖度和林地土壤速效钾影响。为促进三江源天然圆柏林的保护和天然更新,应加强森林封禁管护力度,合理调控林下灌草盖度,提高林地土壤肥力,改善林内生境。The aims of this study were to clarify the regeneration characteristics and dominant factors affecting the regeneration of three natural Juniperus forests in the Three-River Headwater Region of Qinghai Province,and thus to provide a reference for the protection and management of natural forests.We evaluated the natural regeneration levels of Juniperus forests,and the effects of stand factors and soil factors on natural regeneration.The results showed that three natural Juniperus forests were poorly regenerated,with insufficient regeneration potential.The average regeneration density of J.tibetica forest,J.przewalskii forest and J.convallium forest was 332,279 and 202 ind·hm^(-2),respectively.The height range of regenerate individuals was concentrated in 1-3 m.Only a few seedlings(12 ind·hm^(-2))were found under the J.tibetica forest,and no seedlings were found under the J.convallium and J.przewalskii forests.The regeneration density of J.tibetica forest was significantly positively correlated with stand density,soil organic matter and available phosphorus,and negatively correlated with shrub coverage.The regeneration density of J.convallium forest was significantly negatively correlated with herb coverage,human disturbance degree,woodland slope and soil total nitrogen,and positively correlated with soil water content.The regeneration density of J.przewalskii forest was significantly positively correlated with stand density,soil available potassium and available phosphorus,but negatively correlated with herb coverage.Results of multiple regression analysis showed that the regeneration of J.tibetica forest was mainly affected by understory shrub coverage and soil available phosphorus,that of J.convallium forest was mainly affected by understory herb coverage,soil total nitrogen and human disturbance,and that of J.przewalskii forest was mainly affected by understory herb coverage and soil available potassium.It was necessary to strengthen forest enclosure,management and protection,rationally regulate the coverage

关 键 词：三江源 圆柏林 天然更新 林分因子 土壤因子 

分 类 号：S754.1[农业科学—森林经理学]