三种人工林中小型土壤动物群落季节动态特征

Characteristics of soil fauna communities in three typical plantations

为研究四川盆周西缘山地楠木(Phoebe zhennan)、柳杉(Cryptomeria fortune)和水杉(Metasequoia glyptostroboides)人工林下土壤动物群落特征,于2012年7月、10月及次年1月,采用手捡和干湿漏斗法对3种人工林土壤动物进行调查。研究结果显示,本次实验采集土壤动物2776只,分属5门13纲28目,土壤动物类群数排序为:水杉林(24个)>柳杉林(20个)>楠木林(18个),柳杉林土壤动物密度在7月和10月最高,水杉林在1月最高,楠木林土壤动物类群数在各月表现最低。土壤动物剖面密度月动态分析表明,柳杉(除凋落物层外)和水杉林(除10~15cm层外)各层均以10月最高,楠木以7月最高,10月最低(除凋落物层外)。各月优势度指数以水杉林最高,各林分间相似性系数Sorenson较Morisita-Horn波动小,表明土壤动物类群数较个体数更稳定。

Soil fauna is an important component of soil ecosystems,it plays an important role in decomposition of biological remains,affects the soil properties and enhancing material recycling and energy conversion in the soil.To understand the impacts of plantation on soil fauna is essential to achieve sustainable plantation management and conservation of biodiversity. Therefore,an investigation on soil fauna was carried out in three typical plantations. A total of 2776 individuals of soil fauna,belonging to 5 phyla,13 classes and 28 orders were collected,and the average density was 5. 3 × 104 ind./m^2. The soil fauna community was found to be dominated by Collembola and Nematoda in the soil of Phoebe zhennan plantations accounting for 43. 5% and 26. 5% of the individual percentage,respectively. Acarina,Enchytaeidae,Collembola and Nematoda were the dominant groups in Cryptomeria fortune plantations,accounting for 17. 4%,15. 4%,30. 3% and 21. 5% of the individual percentage,respectively. Collembola was the only dominant groups in Metasequoia glyptostroboides plantation accounting for 75. 9% of the individual percentage. The highest soil fauna density was found in Cryptomeria fortune in July and October,and the lowest was found in Metasequoia glyptostroboides plantations in January. The monthly dynamics showed that the highest density of soil fauna in October were found in Metasequoia glyptostroboides plantations（ except for 10-15 cm layer） and Cryptomeria fortune plantations（ except for litter layer）,the highest density of soil fauna in Phoebe zhennan plantations was found in July,and the lowest was in October（ except for litter layer）. The Simpson index of soil fauna in Metasequoia glyptostroboides plantations was higher than that in other plantations at the same month,however,Shannon-Wiener and Pielou index were lower compared with other two plantations because of excessively centralized. Regardless of plantation types at same stage,or the different stages of the same plantation,the fluctuation of Sorenson was lower than Morisita-Horn,which indicated that the group number was more stable than individual number.