林分密度对柠条人工林林下物种多样性及土壤物理性质的影响  

Effects of afforestation density on species diversity and soil physical properties under Caragana korshinskii plantations

作　　者：薛艳春 杨光 陆乃静 石默杰 刘一 代小琴 XUE Yanchun;YANG Guang;LU Naijing;SHI Mojie;LIU Yi;DAI Xiaoqin(College of Desert Management,Inner Mongolia Agricultural University,Hohhot,Inner Mongolia 010018,China;Key Laboratory of Aeolian Sand Physics and Sand Control Engineering,Inner Mongolia Autonomous Region,Hohhot,Inner Mongolia 010018,China;Hulunbuir Water Resources Bureau,Hulunbuir,Inner Mongolia 021000,China;Science and Technology Comprehensive Service Center of Yijin Horuo Banner,Ordos,Inner Mongolia 017000,China)

机构地区：[1]内蒙古农业大学沙漠治理学院,内蒙古呼和浩特010018 [2]内蒙古自治区风沙物理与防沙治沙工程重点实验室,内蒙古呼和浩特010018 [3]呼伦贝尔市水利局,内蒙古呼伦贝尔021000 [4]伊金霍洛旗科学技术综合服务中心,内蒙古鄂尔多斯017000

出　　处：《西北农林科技大学学报（自然科学版）》2024年第10期69-78,共10页Journal of Northwest A&F University(Natural Science Edition)

基　　金：内蒙古自治区科技计划项目“黄土丘陵沟壑区智慧水土保持技术”(2021GG0070)。

摘　　要：【目的】揭示沙区柠条人工林林分密度对林下草本植物群落物种多样性和土壤物理性质的影响,确定柠条林最适林分密度,为其更好地发挥生态服务功能提供参考。【方法】在库布齐沙漠中段鄂尔多斯市达拉特旗造林总场,选择立地条件相同、林龄相近、密度不同的柠条人工林林分为研究对象,选取林分密度为2880~3200株/hm^(2)(Ⅰ)、1800~2000株/hm^(2)(Ⅱ)、1080~1200株/hm^(2)(Ⅲ)、720~800株/hm^(2)(Ⅳ)的林地,以裸沙地为对照(CK),以草本植物群落多样性表征林下物种多样性,记录不同林分中植物的高度、盖度、冠幅等;用五点取样法在各样地取0~20,20~40,40~60,60~80 cm土层土壤,测定其土壤含水量、体积质量、田间持水量和总孔隙度。通过冗余分析探讨植物群落物种多样性与土壤物理性质的相关关系,通过主成分分析对不同密度柠条林进行综合评价。【结果】(1)草本层植物共20种,以菊科植物为主。随林分密度的降低,柠条林林下草本植物群落的Simpson、Shannon-Wiener、Margalef指数呈先增后降趋势,均表现出林分Ⅲ>林分Ⅳ>林分Ⅱ>林分Ⅰ>CK,各林分Peilou均匀度指数与CK无显著差异。(2)柠条人工林的土壤含水量、总孔隙度和田间持水量均以林分Ⅲ最高,分别为5.10%,30.77%,19.16%,土壤体积质量在不同密度林分间无显著差异(P>0.05)。各林分密度土壤含水量在0~40 cm与40~80 cm土层间存在显著差异(P<0.05)。随着土层加深,土壤体积质量呈增加趋势。(3)各密度柠条人工林样地中物种多样性指数与土壤物理性质指标相关性总体较大。(4)不同密度柠条人工林综合评价结果为林分Ⅲ(2.276)>林分Ⅳ(1.261)>林分Ⅱ(0.294)>林分Ⅰ(-0.815)>CK(-3.017)。【结论】1080~1200株/hm^(2)为研究区柠条人工林林下植被与土壤物理性质恢复的适宜密度。【Objective】This study explored the effects of stand density of Caragana korshinskii plantation on species diversity and soil physical properties of herbaceous communities in sandy areas and determined the optimal stand density to provide references for better ecological service function.【Method】In Dalat Banner plantation of Ordos in the middle of Kubuqi Desert,Caragana korshinskii plantations with same site conditions,similar age and different stand densities were selected as the research objects.Woodlands with stand densities of 2880-3200 plants/hm^(2)(Ⅰ),1800-2000 plants/hm^(2)(Ⅱ),1080-1200 plants/hm^(2)(Ⅲ)and 720-800 plants/hm^(2)(Ⅳ)were selected and compared with bare sandy land(CK).Species diversity of understory was characterized by herb community diversity.Height,cover and canopy width of plants in different stands were recorded.Soil water content,volume mass,field water capacity and total porosity were measured at soil layers of 0-20,20-40,40-60 and 60-80 cm by five-point sampling method.Correlations between plant community species diversity and soil physical properties were analyzed by redundancy analysis,and the principal components were used to evaluate Caragana korshinskii plantations.【Result】(1)There were 20 species of herbaceous plants,mainly Compositae.With the decrease of stand density,the Simpson,Shannon-Wiener and Margalef indices of herbaceous communities under Caragana korshinskii stand first increased and then decreased,and the order were in the order of Ⅲ>Ⅳ>Ⅱ>Ⅰ>CK,while the Peilou evenness index showed no significant difference from CK.(2)Soil water content,total porosity and field water capacity of Caragana korshinskii plantation reached the peak values of 5.10%,30.77% and 19.16% at density Ⅲ.There was no significant difference in soil volume and mass among different plots(P>0.05).There were significant differences in soil moisture content between 0-40 cm and 40-80 cm soil layers(P<0.05).With the deepening of soil layer,volume quality of soil increased.(3)There

关 键 词：柠条人工林 物种多样性 林分密度 土壤物理性质 

分 类 号：S793.3[农业科学—林木遗传育种]