马尾松纯林开窗补植油樟对土壤动物群落特征的影响

Effects of Replanting Cinnamomum longipaniculatum in Pinus massoniana Artificial Gaps on Soil Fauna Community Characteristics

为了解马尾松人工林近自然改造对土壤动物群落特征的影响,在马尾松(Pinus massoniana)人工纯林设置4个不同面积大小林窗并补植乡土树种油樟(Cinnamomum longipaniculatum)的基础上,以马尾松纯林为对照(CK),研究改造9 a后4个不同面积油樟斑块(10 m×10 m、20 m×20 m、30 m×30 m、40 m×40 m)中心和边缘土壤动物群落特征;于2020年7月份和12月份,应用环刀法分别在不同面积油樟斑块中心和边缘按不同土层深度(h)“凋落物层、0<h≤5 cm、5 cm<h≤10 cm、10 cm<h≤15 cm”采样,采用干漏斗法(Tullgren法)分离土壤动物,参照《中国土壤动物检索图鉴》、《中国亚热带土壤动物》对土壤动物进行鉴定;采用香农-维纳(Shannon-Wiener)多样性指数、皮洛(Pielou)均匀度指数、辛普森(Simpson)优势度指数、玛格列夫(Margalef)丰富度指数等指标,分析油樟斑块中心和边缘土壤动物群落结构特征。结果表明:试验共采集到土壤动物16296只,2门10纲22目114科。与马尾松纯林相比,斑块改造有利于土壤动物平均密度和类群数的增加,以30 m×30 m斑块样地增幅最高。30 m×30 m斑块样地中心香农-维纳多样性指数最高,马尾松纯林样地最低;10 m×10 m、30 m×30 m、40 m×40 m斑块样地中心的香农-维纳多样性指数,显著高于马尾松纯林(P<0.05);马尾松纯林样地辛普森优势度指数最高,30 m×30 m斑块样地中心的优势度指数最低。土壤动物群落多样性与植物多样性呈正相关,土壤pH、全磷质量分数、有效磷质量分数、有机碳质量分数均与土壤动物群落特征呈显著相关。综合研究结果,马尾松人工纯林开窗补植油樟改造有利于土壤动物群落多样性的提升。

In order to understand the response of soil fauna community to forest gap reconstruction in Pinus massoniana plantation,an experiment was carried out in Laifu Town,Gao County,Sichuan Province.The experiment was based on the former studies which had four forest gaps with different sizes(10 m×10 m,20 m×20 m,30 m×30 m,and 40 m×40 m),and then native tree Cinnamomum longipaniculatum was replanted in each gaps with 2.5 m×2.5 m specifications.Soil was collected according to soil layers(litter layer,0<h≤5 cm,5 cm<h≤10 cm,and 10 cm<h≤15 cm)by ring knife.Soil fauna were separated by Tullgren method,and identification of soil fauna was according to Pictorial Keys to Soil Animals of China and Subtropical soil animals of China.Soil fauna community diversity in the center and edge of each C.longipaniculatum patches were evaluated according to Shannon-Wiener diversity index,Pielou index of evenness,Simpson dominance index and Margalef’s richness index,et al.The results show that:A total of 16296 soil fauna were collected in the experiment,belonging to 114 families,2 phyla,10 classes and 22 orders.Compared with the control(Pinus massoniana pure forest),soil fauna average density and group number increased in each C.longipaniculatum patch,and the highest increase was found in G3 patch.The highest Shannon-Wiener diversity index was found in the center of G3 patch,and the lowest Shannon-Wiener diversity index was found in P.massoniana pure forest.The difference of soil fauna community Shannon-Wiener diversity index between patches(G1,G2 and G4)and P.massoniana pure forest were significant(P<0.05).The highest Simpson dominance index was found in P.massoniana pure forest,and the lowest Simpson dominance index was found in the center of G3 patch.There was positive correlation between soil fauna community diversity and plant diversity,and the significant correlation were found between soil fauna community diversity and soil pH,total phosphorus,available phosphorus and organic carbon respectively(P<0.05).Based on the results,we can get the conclusion that close to nature transformation of pure plantation through forest gaps method(especially G3)have positive impact on the structure of soil animal community.