Responses of soil Collembolans to vegetation restoration in temperate coniferous and broad-leaved mixed forests

A total of 900 soil samples were collected from five habitats,including primary coniferous broad-leaved mixed forests,secondary coniferous broad-leaved mixed forests,secondary broad-leaved forests,secondary shrub forests,and cutover lands in spring,summer,and autumn to quantify responses of soil Collembolans(springtails)to the restoration of vegetation of temperate coniferous and broad-leaved mixed forests.The results reveal that the taxonomic composition of Collembolans varied in the different stages of vegetation restoration.Seasonal variations were in regard to their abundance and richness.High similarities existed in Collembola communities at different stages of vegetation restoration,and distribution patterns of Collembola taxa displayed an evenness throughout all habitats.Soil Collembolans tended to gather on litter layers and soil surface;the highest abundance was found in the upper 5 cm soil layer during the initial stages of vegetation recovery.Tomocerus,Proisotoma,and Folsomia genera responded positively to the restoration of vegetation.However,responses of Ceratophysella and Parisotoma genera were negative.In addition,the Onychiuridae family did not respond to the vegetation restoration process.It was concluded that restoration of vegetative cover can increase the abundance of soil Collembolans,but different genera respond differently.

Collembola communities and soil conditions in forest plantations established in an intensively managed agricultural area

The challenges of a changing climate have directed greater attention to afforestation,but the effects of afforestation on soil fertility and soil biota have not been fully clarified.To explore changes in the soil conditions in two 20-year-old forest plantations established in formerly intensively fertilized plots of agricultural land,we focused on the current developmental state of the sites that received the most fertilizer and evaluated soil properties and Collembola(springtails)communities.Sessile oak(Quercus petraea)and black locust(Robinia pseudoacacia)that had been planted in the afforestation sites were assessed for differences between plantations of native and invasive species.Five adjacent reference associations,including forests and open habitats,were also analyzed and compared.Results showed that the soils in the two afforested sites were similar in their properties and Collembola communities to those of the control cultivated forests,but differed from each other in pH,calcium,phosphorus,and ammonium content.The available potassium and phosphorus contents in the soil of the sessile oak plantation were still high,while the soil organic matter content was adequate(SOM>2.0%)in both plantations.Species richness of Collembola ranged from 18 in the cultivated arable land to 43 in the relict forest.Only a few species typical for forests(e.g.,Neanura muscorum,Isotomiella minor,Entomobrya muscorum)were detected in the young plantations,while species characteristic of open habitats(e.g.,Protaphorura campata,Lepidocyrtus cyaneus)occurred as well.Although more individuals and species of Collembola were present in the soil of young plantations than in arable fields,their community diversities were significantly lower compared to the control forest stands.Collembola community diversity differed significantly also between the two plantation types(with native and non-native tree species).Mean abundance in the afforested sites was about 2.5 times higher than in the cultivated arable land,yet far lower than the mean abundance in the control forests.

Litter decomposition in pure and mixed Quercus and Fagus stands as influenced by arthropods in Belgrad Forest,Turkey

Arthropod assemblages and decomposition rates were compared in the litter of pure and mixed Quercus(Quercus petraea L.)and Fagus(Fagus orientalis L.)stands.Litter was sampled on a monthly basis for 1 year and stored in litterbags of different mesh sizes.The experimental objective was to test the effect of mesh size on litter decomposition,decomposition rates of litter,and diversity of the invertebrate fauna between the two types of stands.Decomposition rates were measured by filling three fiber litterbags of different mesh sizes with pure Quercus litter(3 g)left in the pure Quercus stand,and litterbags with Fagus litter(3 g)were left in the pure Fagus stand.Mixed litter samples were prepared by mixing of equal amounts of each litter in the same litterbag and leaving them in the mixed stand.The residual mass of litter from the pure Quercus stand was significantly lower in fine-and coarse-mesh bags than in the medium-mesh bags in pure the Fagus stand.Carbon and nitrogen levels in the pure Quercus litter were significantly different among the mesh sizes at the end of the incubation period.Macroarthropods from 27 taxa were collected from pitfall traps every month.Their relative numbers differed significantly between the pure and mixed-stand litter samples.Litter-dwelling Isotomidae(Collembola)and Mesostigmata(Acarina),and soil-dwelling Mesostigmata were the most numerous in the mixed stand.It is significant that the abundance of macroarthropods contributed to the mass loss of litter in both the medium and coarse mesh sizes in the mixed stand,but did not significantly affect the mass of litter in the pure stands.In the mixed stand,there was a negative correlation between litter mass loss and total number of microarthropods in all mesh sizes.Mixed-stand litter decomposed more slowly than pure-stand litter.

Collembola associated with edible mushrooms in China

Collembola,a common pest of mushrooms,could reduce the yield and quantity of edible mushroom and causes great economic losses in their production.During the investigation of Collembola in the main edible mushroom production areas in China,27 species belonging to five families and 16 genera,hosted by more than ten species of edible mushrooms have been revealed by morphological and molecular evidence.The most diverse genus was the genus Ceratophysella with five species reported.Fourteen of the 27 species were distributed only in China,while others were widely distributed all over the world.Fifteen species on mushrooms have been barcoded;the results of the species delimitation by mitochondrial COI marker confirmed the results by morphology,with low intra-specific divergences(0-8%).Two Thalassaphorura species,with the only difference being in the presence of parapseudocelli on the anterior ventral head,were clearly differentiated by the molecular markers.

Effects of copper, lead and zinc in soil on egg development and hatching of Folsomia candida

Effects of CaCl2, CuCl2, ZnCl2 and PbCl2 on development and hatching success of eggs of Folsomia candida （Collembola） were studied under laboratory conditions. Thousands of healthy eggs from synchronized cultures were incubated in soils treated with different concentrations of the metals. Compared with the water control, egg hatch significantly decreased when concentrations of Cu, Pb and Zn reached 400, 1 600 and 800 mg/kg dry soil, respectively. Values of EC50（hatching）, calculated according to the exponential model （with 95% confidence limits in brackets）, were 625 （407-875）, 2 361 （2 064-2 687） and 1 763 （1 548-2 000） mg/kg dry soils for Cu, Pb and Zn, respectively. When Cu concentration reached 1 600 mg/kg dry soil, eggs became green and the percentage of green eggs changed from 5%-20% after incubation for 2 days to 15%- 30% after incubation for 4 days. At 3 200 mg Cu/kg dry soil, tissues inside eggs were black and shrunken.

Tonic Immobility Behavior Used by Lobella sokamensis to Adapt Water-saturated Environment in Marshes

Collembola is well known as one of the most important soil meso-faunas of terrestrial ecosystem. As terrestrial arthropods, some water-dependent Collembola live in or near water environment. However, hydrodynamic analysis of water-walking showed that Collembola individuals retain smooth end of claw which are barely high efficient for water walking. The high abundance of Collembola habiting in the wetlands implies an important water-adaptive way of water moving that exists in these animals. This study chose Lobella sokamensis as sample; it is uniquely distributed in and near standing water in the marshes in Northeast China. In order to test the function of water to habitat selecting, free choice behavior experiment was set at a water gradient arena and the effect of the plants in the marshes was analyzed through double choice test. The numbers of the animals stayed at dry, mediated, wet areas were recorded after 0.5 hour, 11 hours, 23 hours, and 32 hours in free choice behavior and analyzed the data with SPSS software. Analogue method and data analysis was applied at double choice test. In order to describe the movement feature of Lobella sokamensis on the water, the activity on the water surface was observed. The results showed that the species had water-repellent and moss-attractive behavior. Tonic immobility gesture was observed when the animal floating on water surface and it was quite efficient for escaping from water when water level was fluctuating. The water flow increased Lobella sokamensis' s transferring in the wetlands. The results illustrated that the moss in the wetlands was vital for distribution of Lobella sokamensis, but tonic immobility was basic for population diffusing for this inactive Collembola. The importance of close connection of moss and water was indicated in the paper, which should be concerned during Collembola biodiversity preserving in the Sanjiang Plain. This is the first demonstration of immobility behavior for water adaptation in Collembola from the wetlands.

Soil compression influences the avoidance behavior of Allonychiurus kimi(Collembola)to cadmium and copper

The behavior of soil organisms inhabiting soil pore spaces can be influenced by soil compression,which can affect their avoidance behavior to pollutants.In this study,we aimed to evaluate the effect of soil compression on the avoidance behavior of Allonychiurus kimi(Collembola)to heavy metals cadmium and copper.Initially,to assess the applicability of the avoidance test guideline of the International Organization for Standardization(ISO)developed for Folsomia candida,we investigated the avoidance behavior of A.kimi to cadmium and copper in an artificial soil with a loose structure(bulk density of 0.25 g cm^(-3)),the porous texture of which was sufficiently loose to enable A.kimi to move between pore spaces.The effect of soil compression on the avoidance behavior of A.kimi to both metals was evaluated in compressed soil(bulk density of 0.64 g cm^(-3))with a uniformly compressed soil surface,and avoidance behavior was investigated at 24-h intervals over a 120-h period.Given that A.kimi is unable to burrow into compressed soil,the compressed soil test can minimize the effects of differences in soil factors,such as soil porosity and bulk density,on the behavior of this collembolan.In the artificial soil,a statistically significant avoidance behavior of A.kimi was observed at cadmium and copper concentrations greater than 50 and 200 mg kg^(-1),respectively,thereby indicating the applicability of the ISO avoidance test guidelines for A.kimi.When compared at the same exposure time point,the avoidance response to both metals in compressed soil was less sensitive than that in uncompressed soil.In addition,we observed differences in the effects of metals on avoidance response in the compressed soil over time,with the effect of cadmium increasing with time and the effect of copper showing the opposite trend.Overall,we found that soil compression can affect the avoidance behavior of A.kimi to cadmium and copper,and we discussed the advantages and limitations of using compressed soil for assessments of pollutant toxicity.