Soil meso- and micro arthropod community diversity in the burned areas of pinus massoniana plantation at different restoration stages

Abstract

Guizhou province, located on the center of southwestern Karst region, is an ecological fragile zone. Fire is one of the important factors that lead to degradation of Karst ecosystem, but the effect of fire disturbance on the structure and diversity of the below-ground soil biota is little known. In order to examine the structure and diversity variation of soil meso- and micro arthropod in different restoration stages of Pinus massoniana plantation after burned, investigations were conducted on forests after 1. 5 months (RS1) burning, 1. 5 years (RS2) burning and unburned Pinus massoniana plantation (CK) in October(Autumn), 2011 and February(Winter), 2012, respectively. The method of Tullgren was used to extract soil meso- and micro arthropod from soil samples. A total of 15704 individuals, belonging to 7 classes, 13 orders, 89 families and 134 groups, were extracted from the soil. The soil meso- and micro arthropod community showed typical zonal characteristics compared with other localities in China. Oppiella and Aenictus were the dominant groups of the soil meso- and micro arthropod community in burned areas, account for 35. 93%. The community taxonomic richness, density and Margalef index (D) of soil meso- and micro arthropod increased significantly with the increasing of the recovery time in Autumn and Winter (P<0. 01). The Shannon-wiener index (H') was not significantly changed in Autumn (P> 0. 05),but increased significantly in Winter (P<0. 001). Simpson index (S) decreased significantly with the increasing of the recovery time in Autumn and Winter (P<0. 001). Pielou index (E) has not significantly changed in Autumn and Winter (P>0. 05). Furthermore, the coefficient of Sorenson suggested that the recovery time had significant effect on taxonomic composition of soil meso-and micro arthropod communities in Autumn and Winter. Pearson correlation analysis showed the taxonomic group and individual density of the community had a significantly positive relationship with TK. In terms of seasonal variation, individual density of soil meso-and micro arthropod showed significant difference between different seasons in RS1 (P<0. 01). The significant seasonal changes were recorded with taxonomic group, individual density, Shannon-wiener index (H') and Pielou index (E) in RS2 (P<0. 05), and the significant seasonal change were also found with taxonomic group, individual density, Shannon-wiener index (H') and Margalef index (D) in CK (P< 0. 05). Season similarities between the different restoration stages, as shown by the Sorenson, indicated that seasonal changes had greater effect on taxonomic composition in RS1 than in RS2 and CK. All the results above suggested that soil meso-and micro arthropod community structure changed significantly, which trended to more complex and stable with the extend of recovery time of Pinus massoniana plantation in Karst ecosystem after fire, its sensitivity of seasonal variation also increased.